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TABLE OF CONTENTS
ITEM 8. FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

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FORM 10-K

Commission File No. 0-30319

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THERAVANCE, INC.
(Exact name of registrant as specified in its charter)

Registrant's telephone number, including area code: 650-808-6000

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SECURITIES REGISTERED PURSUANT TO SECTION 12(b) OF THE ACT:

SECURITIES REGISTERED PURSUANT TO SECTION 12(g) OF THE ACT: NONE

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          Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes ý    No o

          Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes o    No ý

          Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ý    No o

          Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 205 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files). Yes o    No o

          Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§ 229.405) is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K. ý

          Indicate by check mark whether registrant is a large accelerated filer, an accelerated filer or a non-accelerated filer. See definition of "accelerated filer and large accelerated filer" in Rule 12b-2 of the Exchange Act (Check One):

          Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes o    No ý

          The aggregate market value of the voting and non-voting common equity (consisting of Common Stock, $0.01 par value and Class A Common Stock, $0.01 par value) held by non-affiliates of the registrant based upon the closing price of the Common Stock on the Nasdaq Global Market on June 30, 2010 was $592,759,166.

          On February 14, 2011, there were 73,459,110 shares of the registrant's Common Stock and 9,401,499 shares of the registrant's Class A Common Stock outstanding.

DOCUMENTS INCORPORATED BY REFERENCE

          Specified portions of the registrant's definitive Proxy Statement to be issued in conjunction with the registrant's 2011 Annual Meeting of Stockholders, which is expected to be filed not later than 120 days after the registrant's fiscal year ended December 31, 2010, are incorporated by reference into Part III of this Annual Report. Except as expressly incorporated by reference, the registrant's Proxy Statement shall not be deemed to be a part of this Annual Report on Form 10-K.

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THERAVANCE, INC.

2010 Form 10-K Annual Report

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Special Note regarding Forward-Looking Statements

        This Annual Report on Form 10-K contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. Such forward-looking statements involve substantial risks, uncertainties and assumptions. All statements in this Annual Report on Form 10-K, other than statements of historical facts, including statements regarding our strategy, future operations, future financial position, future revenues, projected costs, prospects, plans, intentions, expectations and objectives could be forward-looking statements. The words "anticipates," "believes," "designed," "estimates," "expects," "goal," "intends," "may," "plans," "projects," "pursuing," "will," "would" and similar expressions (including the negatives thereof) are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. We may not actually achieve the plans, intentions, expectations or objectives disclosed in our forward-looking statements and the assumptions underlying our forward-looking statements may prove incorrect. Therefore, you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions, expectations and objectives disclosed in the forward-looking statements that we make. Factors that we believe could cause actual results or events to differ materially from our forward-looking statements include, but are not limited to, those discussed below in "Risk Factors" in Item 1A, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in Item 7 and elsewhere in this Annual Report on Form 10-K. Our forward-looking statements in this Annual Report on Form 10-K are based on current expectations and we do not assume any obligation to update any forward-looking statements.

PART I

ITEM 1.    BUSINESS

Overview

        Theravance is a biopharmaceutical company with a pipeline of internally discovered product candidates and strategic collaborations with pharmaceutical companies. We are focused on the discovery, development and commercialization of small molecule medicines across a number of therapeutic areas including respiratory disease, bacterial infections, and central nervous system (CNS)/pain. Our key development programs include: the RELOVAIR™ program, the LAMA/LABA ('719/vilanterol (VI)) program, and the Bifunctional Muscarinic Antagonist-beta₂ Agonist (MABA) program, each with GlaxoSmithKline plc (GSK), and our Peripherally Selective Mu-Opioid Receptor Antagonist (PµMA) program. By leveraging our proprietary insight of multivalency to drug discovery, we are pursuing a best-in-class strategy designed to discover superior medicines in areas of significant unmet medical need. Our headquarters are located at 901 Gateway Boulevard, South San Francisco, California 94080. Theravance was incorporated in Delaware in November 1996 under the name Advanced Medicine, Inc. and began operations in May 1997. The Company changed its name to Theravance, Inc. in April 2002.

        Our strategy focuses on the discovery, development and commercialization of medicines with superior efficacy, convenience, tolerability and/or safety. Our proprietary approach combines chemistry and biology to discover new product candidates using our expertise in multivalency. Multivalency refers to the simultaneous attachment of a single molecule to multiple binding sites on one or more biological targets. When compared to monovalency, whereby a molecule attaches to only one binding site, multivalency can significantly increase a compound's potency, duration of action and/or selectivity. Multivalent compounds generally consist of several individual small molecules, at least one of which is biologically active when bound to its target, joined by linking components. In addition, we believe that we can enhance the probability of successfully developing and commercializing medicines by identifying at least two structurally different product candidates, whenever practicable, in each therapeutic program.

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        In total, our research and development expenses, including stock-based compensation expense, incurred for all of our therapeutic programs in 2010, 2009, and 2008 were $75.1 million, $77.5 million and $82.0 million, respectively.

        We have entered into the following collaboration arrangements with GSK and Astellas for the development and commercialization of our product candidates:

        In November 2002, we entered into our long-acting beta₂ agonist (LABA) collaboration with GSK to develop and commercialize once-daily LABA products for the treatment of chronic obstructive pulmonary disease (COPD) and asthma. For the treatment of COPD, the collaboration is developing combination products, RELOVAIR™ and the LAMA/LABA '719/VI. For the treatment of asthma, the collaboration is developing RELOVAIR™. RELOVAIR™ is an investigational once-daily combination medicine consisting of a LABA and an inhaled corticosteroid (ICS). '719/VI is an investigational once-daily combination medicine consisting of the long-acting muscarinic antagonist (LAMA) GSK573719 ('719) and the LABA, VI.

        In March 2004 we entered into our strategic alliance agreement with GSK under which GSK received an option to license exclusive development and commercialization rights to product candidates from all of our full drug discovery programs initiated prior to September 1, 2007, on pre-determined terms and on an exclusive, worldwide basis. In 2005, GSK licensed our MABA program under this agreement and commenced a Phase 2b COPD study in December 2010 with GSK961081 ('081), the lead compound in this program.

        Our 2005 collaboration arrangement with Astellas covers the development and commercialization of VIBATIV™ (telavancin), a bactericidal, once-daily injectable antibiotic developed by us for the treatment of Gram-positive infections, including methicillin-resistant Staphylococcus aureus. The U.S. Food and Drug Administration (FDA) has approved VIBATIV™ for the treatment of complicated skin and skin structure infections (cSSSI) caused by susceptible Gram-positive bacteria, including both methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains of Staphylococcus aureus, in adult patients. VIBATIV™ is also approved in Canada for the treatment of cSSSI in adult patients and telavancin is under review by the European Medicines Agency for the treatment of nosocomial pneumonia (NP) and complicated skin and soft tissue infections (cSSTI) in adults.

Our Programs

        Our drug discovery efforts are based on the principles of multivalency. Multivalency involves the simultaneous attachment of a single molecule to multiple binding sites on one or more biological targets. We have applied our expertise in multivalency to discover product candidates and lead compounds in a wide variety of therapeutic areas. We have conducted extensive research in both relevant laboratory and animal models to demonstrate that by applying the design principles of multivalency, we can achieve significantly stronger and more selective attachment of our compounds to a variety of intended biological targets. We believe that medicines that attach more strongly and selectively to their targets will be superior to many medicines by substantially improving potency, duration of action and/or safety.

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        Prior to entering into human clinical studies, a product candidate undergoes preclinical studies which include formulation development or safety testing in animal models. The table below summarizes the status of our most advanced product candidates for internal development or co-development.

        In the table above:

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Development Status indicates the most advanced stage of development that has been completed or is in process.



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Phase 1 indicates initial clinical safety testing in healthy volunteers, or studies directed toward understanding the mechanisms of action of the drug.



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Phase 2 indicates further clinical safety testing and preliminary efficacy testing in a limited patient population.



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Phase 3 indicates evaluation of clinical efficacy and safety within an expanded patient population.



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Filed indicates that a New Drug Application (NDA) or European Marketing Authorization Application (MAA) has been submitted to and accepted for filing by the FDA or European Medicines Agency, respectively.



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We consider programs in which at least one compound has successfully completed a Phase 2a study showing efficacy and tolerability as having achieved Proof-of-Concept.

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Our Relationship with GlaxoSmithKline

LABA collaboration with GSK

        In November 2002, we entered into our LABA collaboration with GSK to develop and commercialize once-daily LABA products for the treatment of COPD and asthma. For the treatment of COPD, the collaboration is developing combination products, RELOVAIR™ and the LAMA/LABA '719/VI. For the treatment of asthma, the collaboration is developing RELOVAIR™. RELOVAIR™ is an investigational once-daily combination medicine consisting of a LABA, vilanterol (VI), previously referred to as GW642444 or '444, and an ICS, fluticasone furoate (FF). The LAMA/LABA '719/VI is an investigational once-daily combination medicine consisting of the LAMA, '719, and the LABA, VI. The RELOVAIR™ program is aimed at developing a next generation respiratory product to succeed GSK's Advair®/Seretide® (salmeterol and fluticasone as a combination) franchise, which had reported 2010 sales of approximately $7.97 billion, and to compete with Symbicort® (formoterol and budesonide as a combination), which had reported 2010 sales of approximately $2.75 billion. '719/VI, which is also a combination product, is targeted as an alternative treatment option to Spiriva® (tiotropium), a once-daily, single-mechanism bronchodilator, which had reported 2009 sales of approximately $3.35 billion.

        The current lead product candidates in our LABA collaboration, VI and FF, were discovered by GSK. In the event that VI is successfully developed and commercialized, we will be obligated to make milestone payments to GSK which could total as much as $220.0 million if both a single-agent and a combination product or two different combination products are launched in multiple regions of the world. If the results of the RELOVAIR™ Phase 3 studies are positive, a portion of these potential milestone payments could be payable to GSK within the next two years. We are entitled to annual royalties from GSK of 15% on the first $3.0 billion of annual global net sales and 5% for all annual global net sales above $3.0 billion. Sales of single-agent LABA medicines and combination medicines would be combined for the purposes of this royalty calculation. For other products combined with a LABA from the LABA collaboration, such as '719/VI, royalties are upward tiering and range from the mid-single digits to 10%. However, if GSK is not selling a LABA/ICS combination product at the time that the first other LABA combination is launched, then the royalties described above for the LABA/ICS combination medicine would be applicable.

        In connection with the LABA collaboration, in 2002, we received from GSK an upfront payment of $10.0 million and sold to an affiliate of GSK shares of our Series E preferred stock for an aggregate purchase price of $40.0 million. Through December 31, 2010, we have received a total of $60.0 million in upfront and development milestone payments, and we do not currently expect to be eligible for any additional milestones under this collaboration.

2004 Strategic Alliance with GSK

        In March 2004, we entered into our strategic alliance with GSK. Under this alliance, GSK received an option to license exclusive development and commercialization rights to product candidates from all of our full drug discovery programs initiated prior to September 1, 2007, on pre-determined terms and on an exclusive, worldwide basis. Pursuant to the terms of the strategic alliance agreement, we initiated three new full discovery programs between May 2004 and August 2007. These three programs are (i) our oral Peripherally Selective Mu-Opioid Receptor Antagonist (PµMA) program for opioid-induced constipation, (ii) our AT1 Receptor-Neprilysin Inhibitor (ARNI) program for cardiovascular disease and (iii) our MonoAmine Reuptake Inhibitor (MARIN) program for chronic pain. GSK still has the right to license the ARNI and MARIN programs, and must exercise this right no later than sixty days subsequent to the final delivery to GSK of all material, data and supporting documentation relating to achievement of clinical proof-of-concept of the first product candidate in the applicable program. For these programs, "proof-of-concept" is generally defined as the successful completion of a

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Phase 2a clinical study showing efficacy and tolerability. Under the terms of the strategic alliance agreement, GSK has only one opportunity to license each of our programs.

        Upon GSK's decision to license a program, GSK is responsible for funding all future development, manufacturing and commercialization activities for product candidates in that program. In addition, GSK is obligated to use diligent efforts to develop and commercialize product candidates from any program that it licenses. Consistent with our strategy, we are obligated to use diligent efforts at our sole cost to discover two structurally different product candidates for any programs on which GSK has an option under the alliance. If these programs are successfully advanced through development by GSK, we are entitled to receive clinical, regulatory and commercial milestone payments and royalties on any sales of medicines developed from these programs. For any programs licensed under this agreement, the royalty structure for a product containing one of our compounds as a single active ingredient would result in an average percentage royalty rate in the low double digits. For single-agent MABA products, we are entitled to receive royalties from GSK of between 10% and 20% of annual global net sales up to $3.5 billion, and 7.5% for all annual global net sales above $3.5 billion. For combination products, such as a MABA/ICS, the royalty rate is 70% of the rate applicable to sales of single-agent MABA medicines. If a product is successfully commercialized, in addition to any royalty revenue that we receive, the total upfront and milestone payments that we could receive in any given program that GSK licenses range from $130.0 million to $162.0 million for programs with single-agent medicines and up to $252.0 million for programs with both a single-agent and a combination medicine. If GSK chooses not to license a program, we retain all rights to the program and may continue the program alone or with a third party. To date, GSK has licensed our two COPD programs: LAMA and MABA. We received $5.0 million payments from GSK in connection with its license of each of our LAMA and MABA programs in August 2004 and March 2005, respectively. In 2009, GSK returned the LAMA program to us because the formulation of the lead product candidate was incompatible with GSK's proprietary inhaler device. GSK has chosen not to license our antibacterial, anesthesia, 5-HT4 and PµMA programs. There can be no assurance that GSK will license either of the two remaining programs under the alliance agreement, which could have an adverse effect on our business and financial condition.

        In connection with the strategic alliance with GSK, we received from GSK an upfront payment of $20.0 million. Through December 31, 2010, we have received $46.0 million in upfront and milestone payments from GSK relating to the strategic alliance agreement.

        In May 2004, GSK purchased through an affiliate 6,387,096 shares of our Class A common stock for an aggregate purchase price of $108.9 million and, upon the closing of our initial public offering on October 8, 2004, GSK purchased through an affiliate an additional 433,757 shares of Class A common stock for an aggregate purchase price of $6.9 million. In addition, on November 29, 2010, GSK purchased through an affiliate in a private placement 5,750,000 shares of our common stock for an aggregate purchase price of $129.4 million. GSK's ownership position of our outstanding stock was approximately 18.3% as of February 14, 2011.

Our Relationship with Astellas

2005 License, Development and Commercialization Agreement with Astellas

        In November 2005, we entered into a collaboration arrangement with Astellas for the development and commercialization of telavancin. In July 2006, Japan was added to the collaboration, thereby giving Astellas worldwide rights to this medicine. Through December 31, 2010, we have received $191.0 million in upfront, milestone and other fees from Astellas. We are eligible to receive potential milestone payments related to regulatory approvals in various regions of the world.

        Under this arrangement, we are responsible for substantially all costs to develop and obtain U.S. regulatory approval for telavancin and Astellas is responsible for substantially all other costs associated with commercialization of telavancin. We are entitled to receive royalties from Astellas on global net

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sales of VIBATIV™ that, on a percentage basis, range from the high teens to the upper twenties depending on sales volume. The FDA has approved VIBATIV™ for the treatment of cSSSI caused by susceptible Gram-positive bacteria, including both methicillin-resistant (MRSA) and methicillin-susceptible (MSSA) strains of Staphylococcus aureus, in adult patients. VIBATIV™ is also approved in Canada for the treatment of cSSSI in adult patients and telavancin is under review by the European Medicines Agency for the treatment of NP and cSSTI in adults.

Development Programs

Respiratory Programs

RELOVAIR™

        In October 2009, we and GSK announced that the first patient had commenced treatment in the Phase 3a program in COPD. The Phase 3a pivotal program in COPD consists of five studies, including two 12-month exacerbation studies, two six-month efficacy and safety studies and a detailed lung function profile study. In March 2010 we and GSK announced that the first patient had commenced treatment in the Phase 3a program in asthma. The Phase 3a program in asthma consists of eight studies, including an exacerbation study, a 12-month safety study (which also supports the COPD program), a 12-week efficacy study, a 24-week efficacy study, and three head-to-head studies and a hypothalamic-pituitary-adrenal (HPA) axis study. GSK is responsible for funding the aforementioned studies. The RELOVAIR™ Phase 3 programs in COPD and asthma are progressing.

        In addition, other studies are planned to assess the potential for superiority of the fixed combination of VI and FF versus other treatments for COPD. In early February 2011, we and GSK announced the initiation of an extensive outcomes study of 16,000 patients across 1,100 global sites to assess the potential for the FF/VI combination to improve survival in patients with COPD and a history of, or at risk from, cardiovascular disease. This study will evaluate the clinical outcomes of patients receiving standard cardiovascular care (including cardiovascular medications) versus patients receiving FF/VI in addition to receiving standard cardiovascular care (including cardiovascular medications).

        In March 2010, the FDA held an Advisory Committee to discuss the design of medical research studies (known as "clinical trial design") to evaluate serious asthma outcomes (such as hospitalizations, a procedure using a breathing tube known as intubation, or death) with the use of LABAs in the treatment of asthma in adults, adolescents, and children. It is unknown at this time what, if any, effect this FDA meeting or future FDA actions will have on the development of the RELOVAIR™ program. The current uncertainty regarding the FDA's position on LABAs for the treatment of asthma and the lack of consensus expressed at the March 2010 Advisory Committee may result in increased time and cost of the asthma clinical trials in the United States for RELOVAIR™ and may increase the overall risk of the RELOVAIR™ asthma program in the United States.

LAMA/LABA

        The LAMA/LABA '719/VI combines two bronchodilator molecules currently under development, the LAMA GSK573719 ('719), and the LABA VI. In early February 2011, we and GSK announced the initiation of the Phase 3 COPD program for the once-daily '719/VI combination which will evaluate over 5,000 patients globally. A 52-week study to evaluate the long term safety and tolerability of '719 (125mcg) alone, as well as the combination '719/VI (125/25mcg), began in February 2011, and will be followed by four large pivotal studies that will compare improvements in lung function between '719/VI, its components, placebo and Spiriva® (tiotropium). The Phase 3 program also will include two further studies assessing the effect of '719/VI on exercise endurance. The Phase 3 program will investigate two doses of '719 (125mcg and 62.5mcg) and '719/VI (125/25mcg and 62.5/25mcg) across the six studies, which are expected to commence by mid-2011. GSK is responsible for funding the aforementioned studies.

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Inhaled Bifunctional Muscarinic Antagonist-beta₂ Agonist (MABA) Program

        In our MABA program, we are developing with GSK a bifunctional long-acting inhaled bronchodilator, GSK961081 ('081) for the treatment of COPD. '081 is a single molecule with both muscarinic antagonist and beta₂ receptor agonist activities. By combining bifunctional activity and high lung selectivity, we intend to develop a medicine with greater efficacy than single-mechanism bronchodilators (such as Spiriva® (tiotropium) or salmeterol) and equal or better tolerability.

        In December 2010, we and GSK announced that the first patient had started treatment with '081 in a Phase 2b study. The overall aim of this Phase 2b study is to evaluate the safety and efficacy of '081 administered both once daily and twice daily over a 28-day period in patients with moderate to severe COPD to allow the selection of a well-tolerated and efficacious dose and dosing interval to take forward into Phase 3 development. GSK is responsible for funding all clinical studies in this program.

Central Nervous System (CNS)/Pain

Peripherally Selective Mu-Opioid Receptor Antagonist (PµMA) Program

        In October 2010, we announced positive proof-of-concept results with TD-1211 in patients with opioid-induced constipation (OIC). TD-1211 is our investigational once-daily, orally-administered, peripherally selective, multivalent inhibitor of the mu-opioid receptor designed to alleviate gastrointestinal side effects of opioid therapy without affecting analgesia. We intend to progress TD-1211 into further Phase 2 work in 2011.

        In January 2011, we announced that we retain sole ownership of our PµMA program as a result of GSK's decision not to exercise its right to license the program under the strategic alliance agreement.

Other Programs

        In addition to RELOVAIR™, '719/VI, MABA and PµMA, we have a number of other clinical-stage programs for bacterial infections, gastrointestinal motility, CNS/pain and cognitive disorders.

        Telavancin is under review by the European Medicines Agency (EMA) for the treatment of NP and cSSTI in adults. We anticipate a response from the EMA later in 2011 regarding the application.

        In November 2010, the FDA issued new draft guidance for antibacterial clinical trial design for the treatment of NP with a focus on mortality as the primary efficacy endpoint. In late 2010, we received a Complete Response Letter from the FDA indicating that the telavancin Phase 3 clinical studies for NP (the ATTAIN studies) do not meet this draft guidance and that additional studies will be required for approval. We do not plan to conduct additional clinical studies for NP, but we do intend to continue a dialogue with the FDA concerning the NP application.

        TD-1792 is our investigational heterodimer antibiotic that combines the antibacterial activities of a glycopeptide and a beta-lactam in one molecule. The goal of our program with TD-1792 is to develop a next-generation antibiotic for the treatment of serious infections caused by Gram-positive bacteria.

        In our MARIN program for the treatment of neuropathic pain, we have successfully completed a single-ascending dose study and a multiple-ascending dose study with compound TD-9855.

        Our Gastrointestinal (GI) Motility Dysfunction program is dedicated to finding new medicines for GI motility disorders such as chronic idiopathic constipation (CIC) and other disorders related to reduced gastrointestinal motility. Our lead compound in this area is TD-5108, a highly selective 5-HT₄ receptor agonist that has successfully completed a 400 patient Phase 2 proof-of-concept study in CIC. The back-up compound in this program, TD-8954, has completed single-ascending and multiple-ascending dose Phase 1 studies.

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        In cognitive disorders, we are evaluating compound TD-5108 as a potential treatment for Alzheimer's disease. TD-5108 has successfully completed a Phase 1 study assessing CNS penetration.

Multivalency

        Our proprietary approach combines chemistry and biology to discover new product candidates using our expertise in multivalency. Multivalency refers to the simultaneous attachment of a single molecule to multiple binding sites on one or more biological targets. When compared to monovalency, whereby a molecule attaches to only one binding site, multivalency can significantly increase a compound's potency, duration of action and/or selectivity. Multivalent compounds generally consist of several individual small molecules, at least one of which is biologically active when bound to its target, joined by linking components.

        Our approach is based on an integration of the following insights:

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many targets have multiple binding sites and/or exist in clusters with similar or different targets;



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biological targets with multiple binding sites and/or those that exist in clusters lend themselves to multivalent drug design;



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molecules that simultaneously attach to multiple binding sites can exhibit considerably greater potency, duration of action and/or selectivity than molecules that attach to only one binding site; and



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greater potency, duration of action and/or selectivity provides the basis for superior therapeutic effects, including enhanced convenience, tolerability and/or safety compared to conventional drugs.

Our Strategy

        Our objective is to discover, develop and commercialize new medicines with superior efficacy, convenience, tolerability and/or safety. The key elements of our strategy are to:

        Apply our expertise in multivalency to discover and develop superior medicines in areas of significant unmet medical need.    We intend to continue to concentrate our efforts on discovering and developing product candidates where:

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existing drugs have levels of efficacy, convenience, tolerability and/or safety that are insufficient to meet an important medical need;



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we believe our expertise in multivalency can be applied to create superior product candidates that are more potent, longer acting and/or more selective than currently available medicines;



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there are established animal models that can be used to provide us with evidence as to whether our product candidates have the potential to provide superior therapeutic benefits relative to current medicines; and



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there is a relatively large commercial opportunity.

        Identify two structurally different product candidates in each therapeutic program whenever practicable.    We believe that we can increase the likelihood of successfully bringing superior medicines to market by identifying, whenever practicable, two product candidates for development in each program. Our second product candidates are typically in a different structural class from the first product candidate. Applying this strategy can reduce our dependence on any one product candidate and provide us with the potential opportunity to commercialize two compounds in a given area.

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        Partner with leading pharmaceutical companies.    Our strategy is to seek collaborations with leading pharmaceutical companies to accelerate development and commercialization of our product candidates at the strategically appropriate time. The LABA collaboration and our strategic alliance with GSK and our telavancin collaboration with Astellas are examples of these types of partnerships.

        Leverage the extensive experience of our people.    We have an experienced senior management team with many years of experience discovering, developing and commercializing new medicines with companies such as Bristol-Myers Squibb Company, Gilead Sciences, Pfizer and ICOS Corporation.

        Improve, expand and protect our technical capabilities.    We have created a substantial body of know-how and trade secrets in the application of our multivalent approach to drug discovery. We believe this is a significant asset that distinguishes us from our competitors. We expect to continue to make substantial investments in drug discovery using multivalency and other technologies to maintain what we believe are our competitive advantages.

Manufacturing

        Though we have limited in-house active pharmaceutical ingredient (API) production capabilities, we primarily rely on a number of third parties, including contract manufacturing organizations and our collaborative partners, to produce our active pharmaceutical ingredient and drug product. Manufacturing of compounds in the RELOVAIR™, '719/VI, and MABA programs is handled by GSK, and Astellas is now responsible for manufacture of VIBATIV™. Additionally, GSK will be responsible for the manufacture of any additional product candidates associated with the programs that it licenses under the strategic alliance agreement.

        We believe that we have in-house expertise to manage a network of third-party manufacturers. We believe that we will be able to continue to negotiate third party manufacturing arrangements on commercially reasonable terms and that it will not be necessary for us to develop internal manufacturing capacity in order to commercialize our products. However, if we are unable to obtain contract manufacturing or obtain such manufacturing on commercially reasonable terms, or if manufacturing is interrupted at one of our suppliers, whether due to regulatory or other reasons, we may not be able to develop or commercialize our products as planned.

Government Regulation

        The development and commercialization of our product candidates and our ongoing research are subject to extensive regulation by governmental authorities in the United States and other countries. Before marketing in the United States, any medicine we develop must undergo rigorous preclinical studies and clinical studies and an extensive regulatory approval process implemented by the FDA under the Federal Food, Drug, and Cosmetic Act. Outside the United States, our ability to market a product depends upon receiving a marketing authorization from the appropriate regulatory authorities. The requirements governing the conduct of clinical studies, marketing authorization, pricing and reimbursement vary widely from country to country. In any country, however, we will be permitted to commercialize our medicines only if the appropriate regulatory authority is satisfied that we have presented adequate evidence of the safety, quality and efficacy of our medicines.

        Before commencing clinical studies in humans in the United States, we must submit to the FDA an Investigational New Drug application that includes, among other things, the results of preclinical studies. If the FDA accepts the Investigational New Drug submission, clinical studies are usually conducted in three phases and under FDA oversight. These phases generally include the following:

        Phase 1.    The product candidate is introduced into healthy human volunteers and is tested for safety, dose tolerance and pharmacokinetics.

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        Phase 2.    The product candidate is introduced into a limited patient population to assess the efficacy of the drug in specific, targeted indications, assess dosage tolerance and optimal dosage, and identify possible adverse effects and safety risks.

        Phase 3.    If a compound is found to be potentially effective and to have an acceptable safety profile in Phase 2 evaluations, the clinical study will be expanded to further demonstrate clinical efficacy, optimal dosage and safety within an expanded patient population.

        The results of product development, preclinical studies and clinical studies must be submitted to the FDA as part of a new drug application, or NDA. The NDA also must contain extensive manufacturing information. NDAs for new chemical entities are subject to performance goals defined in the Prescription Drug User Fee Act (PDUFA) which suggests a goal for FDA action within 6 months for applications that are granted priority review and 10 months for applications that receive standard review. For a product candidate no active ingredient of which has been previously approved by the FDA, the FDA must either refer the product candidate to an advisory committee for review or provide in the action letter on the application for the product candidate a summary of the reasons why the product candidate was not referred to an advisory committee prior to approval. In addition, under the 2008 Food and Drug Administration Amendments Act, the FDA has authority to require submission of a formal Risk Evaluation and Management Strategy (REMS) to ensure safe use of the product. At the end of the review period, the FDA communicates an approval of the NDA or issues a complete response listing the application's deficiencies.

        Once approved, the FDA may withdraw the product approval if compliance with pre- and post-marketing regulatory standards is not maintained or if safety or quality issues are identified after the product reaches the marketplace. In addition, the FDA may require post-marketing studies, referred to as Phase 4 studies, to monitor the effect of approved products, and may limit further marketing of the product based on the results of these post-marketing studies. The FDA has broad post-market regulatory and enforcement powers, including the ability to suspend or delay issuance of approvals, seize products, withdraw approvals, enjoin violations, and institute criminal prosecution.

        If we obtain regulatory approval for a medicine, this clearance to market the product will be limited to those diseases and conditions for which the medicine is effective, as demonstrated through clinical studies and included in the medicine's labeling. Even if this regulatory approval is obtained, a marketed medicine, its manufacturer and its manufacturing facilities are subject to continual review and periodic inspections by the FDA. The FDA ensures the quality of approved medicines by carefully monitoring manufacturers' compliance with its current Good Manufacturing Practice (cGMP) regulations. The cGMP regulations for drugs contain minimum requirements for the methods, facilities, and controls used in manufacturing, processing, and packing of a medicine. The regulations make sure that a medicine is safe for use, and that it has the ingredients and strength it claims to have. Discovery of previously unknown problems with a medicine, manufacturer or facility may result in restrictions on the medicine or manufacturer, including costly recalls or withdrawal of the medicine from the market.

        We are also subject to various laws and regulations regarding laboratory practices, the experimental use of animals and the use and disposal of hazardous or potentially hazardous substances in connection with our research. In each of these areas, as above, the FDA and other regulatory authorities have broad regulatory and enforcement powers, including the ability to suspend or delay issuance of approvals, seize products, withdraw approvals, enjoin violations, and institute criminal prosecution, any one or more of which could have a material adverse effect upon our business, financial condition and results of operations.

        Outside the United States our ability to market our products will also depend on receiving marketing authorizations from the appropriate regulatory authorities. Risks similar to those associated with FDA approval described above exist with the regulatory approval processes in other countries.

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Patents and Proprietary Rights

        We will be able to protect our technology from unauthorized use by third parties only to the extent that our technology is covered by valid and enforceable patents or is effectively maintained as trade secrets. Our success in the future will depend in part on obtaining patent protection for our product candidates. Accordingly, patents and other proprietary rights are essential elements of our business. Our policy is to seek in the United States and selected foreign countries patent protection for novel technologies and compositions of matter that are commercially important to the development of our business. For proprietary know-how that is not patentable, processes for which patents are difficult to enforce and any other elements of our drug discovery process that involve proprietary know-how and technology that is not covered by patent applications, we rely on trade secret protection and confidentiality agreements to protect our interests. We require all of our employees, consultants and advisors to enter into confidentiality agreements. Where it is necessary to share our proprietary information or data with outside parties, our policy is to make available only that information and data required to accomplish the desired purpose and only pursuant to a duty of confidentiality on the part of those parties.

        As of December 31, 2010, we owned 228 issued United States patents and 748 granted foreign patents, as well as additional pending United States patent applications and foreign patent applications. The claims in these various patents and patent applications are directed to compositions of matter, including claims covering product candidates, lead compounds and key intermediates, pharmaceutical compositions, methods of use and processes for making our compounds along with methods of design, synthesis, selection and use relevant to multivalency in general and to our research and development programs in particular. In particular, we own, and license to Astellas, the following U.S. patents which are listed in the FDA Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book) for telavancin: U.S. Patent No. 6,635,618 B2, expiring on September 22, 2021; U.S. Patent No. 6,858,584 B2, expiring on August 24, 2022; U.S. Patent No. 6,872,701 B2, expiring on June 5, 2021; U.S. Patent No. 7,008,923 B2, expiring on May 6, 2021; U.S. Patent No. 7,208,471 B2, expiring on May 1, 2021; U.S. Patent No. 7,351,691 B2, expiring on May 1, 2021; U.S. Patent No. 7,531,623 B2, expiring on January 1, 2027; U.S. Patent No. 7,544,364 B2, expiring on May 1, 2021; and U.S. Patent No. 7,700,550 B2, expiring on May 1, 2021. On October 15, 2009, we filed patent term extension (PTE) applications in the United States Patent and Trademark Office (USPTO) for U.S. Patent Nos. 6,635,618 B2; 6,872,701 B2; and 7,208,471 B2. These PTE applications are currently pending and if granted, we will be permitted to extend the term of one of these patents for the period determined by the USPTO.

        United States issued patents and foreign patents generally expire 20 years after filing. The patent rights relating to telavancin owned by us and licensed to Astellas currently consist of United States patents that expire between 2019 and 2027, additional pending United States patent applications and counterpart patents and patent applications in a number of jurisdictions, including Europe. Nevertheless, issued patents can be challenged, narrowed, invalidated or circumvented, which could limit our ability to stop competitors from marketing similar products and threaten our ability to commercialize our product candidates. Our patent position, similar to other companies in our industry, is generally uncertain and involves complex legal and factual questions. To maintain our proprietary position we will need to obtain effective claims and enforce these claims once granted. It is possible that, before any of our products can be commercialized, any related patent may expire or remain in force only for a short period following commercialization, thereby reducing any advantage of the patent. Also, we do not know whether any of our patent applications will result in any issued patents or, if issued, whether the scope of the issued claims will be sufficient to protect our proprietary position.

        We have entered into a License Agreement with Janssen Pharmaceutica pursuant to which we have licensed rights under certain patents owned by Janssen covering an excipient used in the formulation of telavancin. We believe that the general and financial terms of the agreement with

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Janssen are ordinary course terms. Pursuant to the terms of this license agreement, we are obligated to pay royalties and milestone payments to Janssen based on any commercial sales of telavancin. Astellas has agreed to assume responsibility for these payments under the terms of our license agreement with them. The license is terminable by us upon prior written notice to Janssen or upon an uncured breach or a liquidation event of one of the parties.

Competition

        Our objective is to discover, develop and commercialize new medicines with superior efficacy, convenience, tolerability and/or safety. We expect that any medicines that we commercialize with our collaborative partners or on our own will compete with existing and future market-leading medicines.

        Many of our potential competitors have substantially greater financial, technical and personnel resources than we have. In addition, many of these competitors have significantly greater commercial infrastructures than we have. Our ability to compete successfully will depend largely on our ability to leverage our experience in drug discovery and development to:

•

discover and develop medicines that are superior to other products in the market;



•

attract qualified scientific, product development and commercial personnel;



•

obtain patent and/or other proprietary protection for our medicines and technologies;



•

obtain required regulatory approvals; and



•

successfully collaborate with pharmaceutical companies in the discovery, development and commercialization of new medicines.

        LABA Collaboration with GSK.    We anticipate that, if approved, any product from our LABA collaboration with GSK, including RELOVAIR™ and the LAMA/LABA '719/VI, will compete with a number of approved bronchodilator drugs and drug candidates under development that are designed to treat asthma and COPD. These include but are not limited to Advair®/Seretide® (salmeterol and fluticasone as a combination) marketed by GSK, Foradil®/Oxis® (formoterol) marketed by a number of companies, Symbicort® (formoterol and budesonide as a combination) marketed by AstraZeneca Dulera®(formoterol and mometasone as a combination) marketed by Merck, and Spiriva® (tiotropium) marketed by Boehringer-Ingelheim and Pfizer. Onbrez®(indacaterol) is being developed as a single-agent by Novartis and, for markets outside of the United States, in combination with an ICS (mometasone). In addition, indacaterol combined with a muscarinic antagonist is being developed by Novartis. Boehringer-Ingelheim is developing a combination product with tiotropium and the long-acting beta agonist olodaterol for the treatment of COPD. In addition, several firms are reported to be developing new formulations of salmeterol-fluticasone and formoterol-budesonide which may be marketed as generics or branded generics relative to the existing products from GSK and AstraZeneca, respectively. All of these efforts represent potential competition for any product from our LABA collaboration.

        VIBATIV™ (telavancin).    VIBATIV™ competes with vancomycin, a generic drug that is manufactured by a variety of companies, as well as other drugs marketed to treat complicated skin and skin structure infections caused by Gram-positive bacteria. Currently marketed products include but are not limited to Cubicin® (daptomycin) marketed by Cubist Pharmaceuticals, Xyvox® (linezolid) marketed by Pfizer and Tygacil® (tigecycline) marketed by Wyeth. In addition, Teflaro™ (ceftaroline) to be marketed by Forest Laboratories was approved by the FDA in October 2010 and launch is expected in 2011. To compete effectively with these medicines, and in particular with the relatively inexpensive generic option of vancomycin, we and our partner Astellas will need to demonstrate to physicians that, based on experience, clinical data, side-effect profiles and other factors, VIBATIV™ is preferable to

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vancomycin and other existing or subsequently-developed anti-infective drugs in certain clinical situations.

        In addition, as the principles of multivalent medicine design become more widely known and appreciated based on patent and scientific publications and regulatory filings, we expect the field to become highly competitive. Pharmaceutical companies, biotechnology companies and academic and research institutions may seek to develop product candidates based upon the principles underlying our multivalent technologies.

Employees

        As of December 31, 2010, we had 193 employees, 142 of which were primarily engaged in research and development activities. None of our employees are represented by a labor union. We consider our employee relations to be good.

Available Information

        Our Internet address is www.theravance.com. Our investor relations website is located at http://ir.theravance.com. We make available free of charge on our investors relations website under "SEC Filings" our Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, our directors' and officers' Section 16 Reports and any amendments to those reports as soon as reasonably practicable after filing or furnishing such materials to the U.S. Securities and Exchange Commission (SEC). The information found on our website is not part of this or any other report that we file with or furnish to the SEC. Theravance and the Theravance logo are registered trademarks of Theravance, Inc. Trademarks, tradenames or service marks of other companies appearing in this report are the property of their respective owners.

ITEM 1A.    RISK FACTORS

        In addition to the other information in this Annual Report on Form 10-K, the following risk factors should be considered carefully in evaluating our business and us.

Risks Related to our Business

If the RELOVAIR™ Phase 3 program in asthma or chronic obstructive pulmonary disease (COPD) does not demonstrate safety and efficacy, the RELOVAIR™ program will be significantly delayed or terminated, our business will be harmed, and the price of our securities could fall.

        The RELOVAIR™ Phase 3a program for COPD commenced in October 2009, the RELOVAIR™ Phase 3a program for asthma commenced in March 2010 and the RELOVAIR™ Phase 3b program for COPD commenced in February 2011. Any adverse developments or results or perceived adverse developments or results with respect to the RELOVAIR™ program will significantly harm our business and could cause the price of our securities to fall. Examples of such adverse developments include, but are not limited to:

•

the U.S. Food and Drug Administration (FDA) determining that additional clinical studies are required with respect to the Phase 3a program in asthma or the Phase 3 program in COPD;



•

inability to gain, or delay in gaining, regulatory approval for the new delivery device used in the program;



•

safety or other concerns arising from ongoing preclinical or clinical studies in this program, including, without limitation, the COPD extensive outcomes study initiated in February 2011;



•

safety or other concerns arising from the LAMA/LABA '719/VI Phase 3 program having to do with the LABA, VI, which is also a component of RELOVAIR™;



•

the Phase 3a program in asthma or the Phase 3 program in COPD raising safety concerns or not demonstrating efficacy; or



•

any change in FDA policy or guidance regarding the use of long-acting beta₂ agonists (LABAs) to treat asthma.

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        On February 18, 2010, the FDA announced that LABAs should not be used alone in the treatment of asthma and will require manufacturers to include this warning in the product labels of these drugs, along with taking other steps to reduce the overall use of these medicines. The FDA will now require that the product labels for LABA medicines reflect, among other things, that the use of LABAs is contraindicated without the use of an asthma controller medication such as an inhaled corticosteroid, that LABAs should only be used long-term in patients whose asthma cannot be adequately controlled on asthma controller medications, and that LABAs should be used for the shortest duration of time required to achieve control of asthma symptoms and discontinued, if possible, once asthma control is achieved. In addition, on March 10 and 11, 2010, the FDA held an Advisory Committee to discuss the design of medical research studies (known as "clinical trial design") to evaluate serious asthma outcomes (such as hospitalizations, a procedure using a breathing tube known as intubation, or death) with the use of LABAs in the treatment of asthma in adults, adolescents, and children. It is unknown at this time what, if any, effect these or future FDA actions will have on the development of the RELOVAIR™ program. The current uncertainty regarding the FDA's position on LABAs for the treatment of asthma and the lack of consensus expressed at the March 2010 Advisory Committee may result in increased time and cost of the asthma clinical trials in the United States for RELOVAIR™ and may increase the overall risk of the RELOVAIR™ asthma program in the United States.

If the '719/VI Phase 3 program for the treatment of COPD does not demonstrate safety and efficacy, the '719/VI program will be significantly delayed or terminated, our business will be harmed, and the price of our securities could fall.

        The '719/VI Phase 3 program with the combination of the LABA vilanterol, or VI, and the long-acting muscarinic antagonist (LAMA) GSK573719, or '719, for the treatment of COPD commenced in February 2011. Any adverse developments or results or perceived adverse developments or results with respect to the '719/VI program will significantly harm our business and could cause the price of our securities to fall. Examples of such adverse developments include, but are not limited to:

•

the FDA determining that additional clinical studies are required with respect to the Phase 3 program in COPD;



•

inability to gain, or delay in gaining, regulatory approval for the new delivery device used in the program;



•

safety or other concerns arising from ongoing preclinical or clinical studies in this program;



•

safety or other concerns arising from the RELOVAIR™ Phase 3 program having to do with the LABA, VI, which is also a component of '719/VI;



•

the Phase 3 program in COPD raising safety concerns or not demonstrating efficacy; or



•

any change in FDA policy or guidance regarding the use of LABAs combined with a LAMA to treat COPD.

If the MABA Phase 2b study for the treatment of COPD does not demonstrate safety and efficacy, the MABA program will be significantly delayed or terminated, our business will be harmed, and the price of our securities could fall.

        The Phase 2b COPD clinical study with the lead compound, GSK961081 ('081), in the bifunctional muscarinic antagonist-beta₂ agonist (MABA) program with GSK commenced in December 2010. Any adverse developments or results or perceived adverse developments or results with respect to this study

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will harm our business and could cause the price of our securities to fall. Examples of such adverse developments include, but are not limited to:

•

the FDA determining that additional pre-clincal or earlier stage clinical studies are required with respect to the MABA program;



•

inability to gain, or delay in gaining, regulatory approval for the new delivery device used in the program;



•

safety or other concerns arising from ongoing preclinical or clinical studies in this program;



•

the Phase 2b study raising safety concerns or not demonstrating efficacy; or



•

any change in FDA policy or guidance regarding the use of MABAs to treat COPD.

If telavancin is not approved in additional countries and for additional indications, our business will be adversely affected and the price of our securities could fall.

        On October 28, 2009, Astellas Pharma Europe B.V., a subsidiary of our telavancin partner, Astellas Pharma Inc. (Astellas), announced that it submitted a new European Marketing Authorization Application (MAA) for telavancin to the European Medicines Agency for the treatment of complicated skin and soft tissue infections (cSSTI) and nosocomial pneumonia (NP). On November 30, 2009, we announced that the European Medicines Agency had completed the validation phase for the MAA and the European Medicines Agency's scientific review process had begun. In October 2008, we announced that Astellas Pharma Europe B.V. voluntarily withdrew a previously filed MAA for telavancin for the treatment of cSSTI from the European Medicines Agency based on communications from the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency that the data provided were not sufficient to allow the CHMP to conclude a positive benefit-risk balance for telavancin for the sole indication of cSSTI at that time.

        If the European Medicines Agency does not approve the MAA, requires data from additional clinical studies regarding telavancin, or if telavancin is ultimately approved by the European Medicines Agency but with restrictions, including labeling that may limit the targeted patient population, our business will be harmed and the price of our securities could fall.

        Our first New Drug Application (NDA), for VIBATIV™ (telavancin) for the treatment of complicated skin and skin structure infections (cSSSI) caused by susceptible Gram-positive bacteria in adult patients, was approved by the FDA in September 2009. In January 2009, we submitted a second telavancin NDA to the FDA for the NP indication based on data from our two Phase 3 clinical studies referred to as the ATTAIN studies. During the fourth quarter of 2010 the FDA issued new draft guidance for antibacterial clinical trial design for the treatment of NP with a focus on mortality as the primary efficacy endpoint. The ATTAIN studies, which were conducted pursuant to then-current draft FDA guidelines and completed prior to the issuance of this new draft guidance, used clinical response as the primary efficacy endpoint. In late 2010, we received a Complete Response Letter from the FDA indicating that the ATTAIN studies do not meet the new draft guidance and that additional clinical studies will be required for approval. We do not plan to conduct additional clinical studies for NP, but we do intend to continue a dialogue with FDA concerning the NP NDA. Lack of FDA approval for use of telavancin to treat NP has adversely affected and will continue to adversely affect commercialization of this medicine in the United States.

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If any product candidates, in particular those in any respiratory program with GSK, are determined to be unsafe or ineffective in humans, our business will be adversely affected and the price of our securities could fall.

        Although our first approved product, VIBATIV™, was commercially launched in the U.S. by our partner Astellas in November 2009, we have not yet commercialized any of our other product candidates. We are uncertain whether any of our other product candidates will prove effective and safe in humans or meet applicable regulatory standards. In addition, our approach to applying our expertise in multivalency to drug discovery may not result in the creation of successful medicines. The risk of failure for our product candidates is high. For example, in late 2005, we discontinued our overactive bladder program based upon the results of our Phase 1 studies with compound TD-6301, and GSK discontinued development of TD-5742, the first LAMA compound licensed from us, after completing a single-dose Phase 1 study. The data supporting our drug discovery and development programs is derived solely from laboratory experiments, preclinical studies and clinical studies. A number of other compounds remain in the lead identification, lead optimization, preclinical testing or early clinical testing stages.

        Several well-publicized Complete Response letters issued by the FDA and safety-related product withdrawals, suspensions, post-approval labeling revisions to include boxed warnings and changes in approved indications over the last few years, as well as growing public and governmental scrutiny of safety issues, have created an increasingly conservative regulatory environment. The implementation of new laws and regulations, and revisions to FDA clinical trial design guidance, have increased uncertainty regarding the approvability of a new drug. Further, there are additional requirements for approval of new drugs, including advisory committee meetings for new chemical entities, and formal risk evaluation and mitigation strategy (REMS) at the FDA's discretion. These new laws, regulations, additional requirements and changes in interpretation could cause non-approval or further delays in the FDA's review and approval of our product candidates.

With regard to all of our programs, any delay in commencing or completing clinical studies for product candidates and any adverse results from clinical or preclinical studies or regulatory obstacles product candidates may face, would harm our business and could cause the price of our securities to fall.

        Each of our product candidates must undergo extensive preclinical and clinical studies as a condition to regulatory approval. Preclinical and clinical studies are expensive, take many years to complete and study results may lead to delays in further studies or decisions to terminate programs. For example, we had planned to commence the Phase 2b clinical study in our MABA program with GSK in 2009, but the program was delayed until late 2010.

        The commencement and completion of clinical studies for our product candidates may be delayed by many factors, including:

•

lack of effectiveness of product candidates during clinical studies;



•

adverse events, safety issues or side effects relating to the product candidates or their formulation into medicines;



•

inability to raise additional capital in sufficient amounts to continue our development programs, which are very expensive;



•

the need to sequence clinical studies as opposed to conducting them concomitantly in order to conserve resources;



•

our inability to enter into partnering arrangements relating to the development and commercialization of our programs and product candidates;

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•

our inability or the inability of our collaborators or licensees to manufacture or obtain from third parties materials sufficient for use in preclinical and clinical studies;



•

governmental or regulatory delays and changes in regulatory requirements, policy and guidelines;



•

failure of our partners to advance our product candidates through clinical development;



•

delays in patient enrollment and variability in the number and types of patients available for clinical studies;



•

difficulty in maintaining contact with patients after treatment, resulting in incomplete data;



•

varying interpretations of data by the FDA and similar foreign regulatory agencies; and



•

a regional disturbance where we or our collaborative partners are enrolling patients in our clinical trials, such as a pandemic, terrorist activities or war, political unrest or a natural disaster.

If our product candidates that we develop on our own or through collaborative partners are not approved by regulatory agencies, including the FDA, we will be unable to commercialize them.

        The FDA must approve any new medicine before it can be marketed and sold in the United States. We must provide the FDA and similar foreign regulatory authorities with data from preclinical and clinical studies that demonstrate that our product candidates are safe and effective for a defined indication before they can be approved for commercial distribution. We will not obtain this approval for a product candidate unless and until the FDA approves a NDA. The processes by which regulatory approvals are obtained from the FDA to market and sell a new product are complex, require a number of years and involve the expenditure of substantial resources. In order to market our medicines in foreign jurisdictions, we must obtain separate regulatory approvals in each country. The approval procedure varies among countries and can involve additional testing, and the time required to obtain approval may differ from that required to obtain FDA approval. Approval by the FDA does not ensure approval by regulatory authorities in other countries, and approval by one foreign regulatory authority does not ensure approval by regulatory authorities in other foreign countries or by the FDA. Conversely, failure to obtain approval in one or more jurisdictions may make approval in other jurisdictions more difficult.

        Clinical studies involving our product candidates may reveal that those candidates are ineffective, inferior to existing approved medicines, unacceptably toxic, or that they have other unacceptable side effects. In addition, the results of preclinical studies do not necessarily predict clinical success, and larger and later-stage clinical studies may not produce the same results as earlier-stage clinical studies.

        Frequently, product candidates that have shown promising results in early preclinical or clinical studies have subsequently suffered significant setbacks or failed in later clinical studies. In addition, clinical studies of potential products often reveal that it is not possible or practical to continue development efforts for these product candidates. If our clinical studies are substantially delayed or fail to prove the safety and effectiveness of our product candidates in development, we may not receive regulatory approval of any of these product candidates and our business and financial condition will be materially harmed and the price of our securities may fall.

VIBATIV™ may not be accepted by physicians, patients, third party payors, or the medical community in general.

        The commercial success of VIBATIV™ depends upon its acceptance by physicians, patients, third party payors and the medical community in general. We cannot be sure that VIBATIV™ will be accepted by these parties. VIBATIV™ competes with vancomycin, a relatively inexpensive generic drug that is manufactured by a variety of companies, and a number of existing antibacterials manufactured and marketed by major pharmaceutical companies and others, and may compete against new

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antibacterials that are not yet on the market. Even if the medical community accepts that VIBATIV™ is safe and efficacious for its indicated use, physicians may choose to restrict the use of VIBATIV™. If we and our partner, Astellas, are unable to demonstrate to physicians that, based on experience, clinical data, side-effect profiles and other factors, VIBATIV™ is preferable to vancomycin and other antibacterial drugs, we may never generate meaningful revenue from VIBATIV™ which could cause the price of our securities to fall. The degree of market acceptance of VIBATIV™ depends on a number of factors, including, but not limited to:

•

the demonstration of the clinical efficacy and safety of VIBATIV™;



•

the reactions of physicians, patients and payors to the approved cSSSI labeling for VIBATIV™ in the U.S.;



•

whether or not VIBATIV™ is approved by regulatory authorities in Europe or other jurisdictions;



•

the advantages and disadvantages of VIBATIV™ compared to alternative therapies;



•

potential negative perceptions of physicians related to our inability to obtain FDA approval of our NP NDA;



•

our and Astellas' ability to educate the medical community about the safety and effectiveness of VIBATIV™;



•

the reimbursement policies of government and third party payors; and



•

the market price of VIBATIV™ relative to competing therapies.

Even if our product candidates receive regulatory approval, such as VIBATIV™, commercialization of such products may be adversely affected by regulatory actions and oversight.

        Even if we receive regulatory approval for our product candidates, this approval may include limitations on the indicated uses for which we can market our medicines or the patient population that may utilize our medicines, which may limit the market for our medicines or put us at a competitive disadvantage relative to alternative therapies. For example, VIBATIV™'s labeling contains a boxed warning regarding the risks of use of VIBATIV™ during pregnancy. Products with boxed warnings are subject to more restrictive advertising regulations than products without such warnings. These restrictions could make it more difficult to market VIBATIV™ effectively. Further, now that VIBATIV™ is approved, we remain subject to continuing regulatory obligations, such as safety reporting requirements and additional post-marketing obligations, including regulatory oversight of promotion and marketing.

        In addition, the labeling, packaging, adverse event reporting, advertising, promotion and recordkeeping for the approved product remain subject to extensive and ongoing regulatory requirements. If we become aware of previously unknown problems with an approved product in the U.S. or overseas or at contract manufacturers' facilities, a regulatory agency may impose restrictions on the product, the contract manufacturers or on us, including requiring us to reformulate the product, conduct additional clinical studies, change the labeling of the product, withdraw the product from the market or require the contract manufacturer to implement changes to its facilities. In addition, we may experience a significant drop in the sales of the product, our royalties on product revenues and reputation in the marketplace may suffer, and we could face lawsuits.

        We are also subject to regulation by regional, national, state and local agencies, including the Department of Justice, the Federal Trade Commission, the Office of Inspector General of the U.S. Department of Health and Human Services and other regulatory bodies with respect to VIBATIV™, as well as governmental authorities in those foreign countries in which any of our product candidates are

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approved for commercialization. The Federal Food, Drug, and Cosmetic Act, the Public Health Service Act and other federal and state statutes and regulations govern to varying degrees the research, development, manufacturing and commercial activities relating to prescription pharmaceutical products, including preclinical and clinical testing, approval, production, labeling, sale, distribution, import, export, post-market surveillance, advertising, dissemination of information and promotion. If we or any third parties that provide these services for us are unable to comply, we may be subject to regulatory or civil actions or penalties that could significantly and adversely affect our business. Any failure to maintain regulatory approval will limit our ability to commercialize our product candidates, which would materially and adversely affect our business and financial condition, which may cause our stock price to decline.

We have incurred operating losses in each year since our inception and expect to continue to incur substantial losses for the foreseeable future.

        We have been engaged in discovering and developing compounds and product candidates since mid-1997. Our first approved product, VIBATIV™, was launched by our partner Astellas in the U.S. in November 2009, and to date we have received modest royalty revenues. From the commercial launch through December 31, 2010, Astellas recorded VIBATIV™ net sales of $10.5 million. We recognize royalty revenue from Astellas in the period the royalties are earned based on net sales of VIBATIV™ by Astellas as reported to us by Astellas. We may never generate sufficient revenue from the sale of medicines or royalties on sales by our partners to achieve profitability. As of December 31, 2010, we had an accumulated deficit of approximately $1.2 billion.

        We expect to incur substantial expenses as we continue our drug discovery and development efforts, particularly to the extent we advance our product candidates into and through clinical studies, which are very expensive. As a result, we expect to continue to incur substantial losses for the foreseeable future. We are uncertain when or if we will be able to achieve or sustain profitability. Failure to become and remain profitable would adversely affect the price of our securities and our ability to raise capital and continue operations.

If we fail to obtain the capital necessary to fund our operations, we may be unable to develop our product candidates and we could be forced to share our rights to commercialize our product candidates with third parties on terms that may not be favorable to us.

        We need large amounts of capital to support our research and development efforts. If we are unable to secure capital to fund our operations we will not be able to continue our discovery and development efforts and we might have to enter into strategic collaborations that could require us to share commercial rights to our medicines to a greater extent than we currently intend. Based on our current operating plans, milestone and royalty forecasts and spending assumptions, we believe that our cash and cash equivalents and marketable securities will be sufficient to meet our anticipated operating needs for at least the next twelve months. We are likely to require additional capital to fund operating needs thereafter. Though we have no current intention to do so, if we were to conduct additional studies to support the telavancin NP NDA and we were required to fund such studies, our capital needs could increase substantially. We intend to continue clinical development of the lead compounds in our PµMA and MARIN programs, and anticipate initiating additional Phase 2 and Phase 2b studies for PµMA and additional Phase 1 studies and a Phase 2 study for MARIN. We also intend to conduct a number of other preclinical and clinical studies in other programs. In addition, under our LABA collaboration with GSK, in the event that vilanterol (VI), which is the current lead LABA product candidate in the RELOVAIR™ and LAMA/LABA ('719/VI) programs and which was discovered by GSK, is approved and launched in multiple regions of the world as both a single agent and a combination product or two different combination products, we will be obligated to pay GSK milestone payments that could total as much as $220.0 million and we would not be entitled to receive any

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further milestone payments from GSK . We cannot guarantee that future financing will be available in sufficient amounts or on terms acceptable to us, if at all. Even if we are able to raise additional capital, such financing may result in significant dilution to existing security holders. If we are unable to raise additional capital in sufficient amounts or on terms acceptable to us, we may have to make additional reductions in our workforce and may be prevented from continuing our discovery and development efforts and exploiting other corporate opportunities. This could harm our business, prospects and financial condition and cause the price of our securities to fall.

If our partners do not satisfy their obligations under our agreements with them, or if they terminate our partnership with them, we will be unable to develop our partnered product candidates as planned.

        We entered into our LABA collaboration agreement with GSK in November 2002, our strategic alliance agreement with GSK in March 2004, and our telavancin development and commercialization agreement with Astellas in November 2005. In connection with these agreements, we have granted to these parties certain rights regarding the use of our patents and technology with respect to compounds in our development programs, including development and marketing rights. Under our GSK agreements, GSK has full responsibility for development and commercialization of any product candidates in the RELOVAIR™, LAMA/LABA ('719/VI) and MABA programs. Any future milestone payments or royalties to us from these programs will depend on the extent to which GSK advances the product candidate through development and commercial launch. In connection with our license, development and commercialization agreement with Astellas, Astellas is responsible for the commercialization of VIBATIV™ and any royalties to us from net sales of VIBATIV™ will depend upon Astellas' ability to commercialize the medicine.

        Our partners might not fulfill all of their obligations under these agreements, and, in certain circumstances, they may terminate our partnership with them. In either event, we may be unable to assume the development and commercialization of the product candidates covered by the agreements or enter into alternative arrangements with a third party to develop and commercialize such product candidates. In addition, with the exception of product candidates in our LABA collaboration, our partners generally are not restricted from developing and commercializing their own products and product candidates that compete with those licensed from us. If a partner elected to promote its own products and product candidates in preference to those licensed from us, future payments to us could be reduced and our business and financial condition would be materially and adversely affected. Accordingly, our ability to receive any revenue from the product candidates covered by these agreements is dependent on the efforts of the partner. We could also become involved in disputes with a partner, which could lead to delays in or termination of our development and commercialization programs and time-consuming and expensive litigation or arbitration.

        If a partner terminates or breaches its agreements with us, or otherwise fails to complete its obligations in a timely manner, the chances of successfully developing or commercializing our product candidates would be materially and adversely affected. For example, under the terms of our telavancin license, development and commercialization agreement, Astellas has the right to terminate the agreement since VIBATIV™ was not approved by December 31, 2008. If Astellas chooses to terminate the agreement, the further commercialization of VIBATIV™ would be delayed, our business could be harmed and the price of our securities could fall.

        In addition, while our strategic alliance with GSK sets forth pre-agreed upfront payments, development obligations, milestone payments and royalty rates under which GSK may obtain exclusive rights to develop and commercialize certain of our product candidates, GSK may in the future seek to negotiate more favorable terms on a project-by-project basis. To date, GSK has licensed our LAMA program and our MABA program under the terms of the strategic alliance agreement and has chosen not to license our antibacterial, anesthesia, 5-HT₄ and PµMA programs. In February 2009, GSK returned the LAMA program to us because the formulation of the lead product candidate was

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incompatible with GSK's proprietary inhaler device. There can be no assurance that GSK will license any other development program under the terms of the strategic alliance agreement, or at all. GSK's failure to license our development programs, or its return of programs to us, could adversely affect the perceived prospects of the product candidates that are the subject of these development programs, which could negatively affect both our ability to enter into collaborations for these product candidates with third parties and the price of our securities.

We rely on a limited number of manufacturers for our product candidates, and our business will be harmed if these manufacturers are not able to satisfy our demand and alternative sources are not available.

        We have limited in-house active pharmaceutical ingredient (API) production capabilities and depend primarily on a number of third-party API and drug product manufacturers. We may not have long-term agreements with these third parties and our agreements with these parties may be terminable at will by either party at any time. If, for any reason, these third parties are unable or unwilling to perform, or if their performance does not meet regulatory requirements, we may not be able to locate alternative manufacturers or enter into favorable agreements with them. Any inability to acquire sufficient quantities of API and drug product in a timely manner from these third parties could delay clinical studies, prevent us from developing our product candidates in a cost-effective manner or on a timely basis. In addition, manufacturers of our API and drug product are subject to the FDA's current good manufacturing practice (cGMP) regulations and similar foreign standards and we do not have control over compliance with these regulations by our manufacturers.

        Our manufacturing strategy presents the following additional risks:

•

because of the complex nature of our compounds, our manufacturers may not be able to successfully manufacture our APIs and/or drug products in a cost effective and/or timely manner and changing manufacturers for our APIs or drug products could involve lengthy technology transfer and validation activities for the new manufacturer;



•

the processes required to manufacture certain of our APIs and drug products are specialized and available only from a limited number of third-party manufacturers;



•

some of the manufacturing processes for our APIs and drug products have not been scaled to quantities needed for continued clinical studies or commercial sales, and delays in scale-up to commercial quantities could delay clinical studies, regulatory submissions and commercialization of our product candidates; and



•

because some of the third-party manufacturers are located outside of the U.S., there may be difficulties in importing our APIs and drug products or their components into the U.S. as a result of, among other things, FDA import inspections, incomplete or inaccurate import documentation or defective packaging.

Our relationship with GSK may have a negative effect on our ability to enter into relationships with third parties.

        As of February 14, 2011, GSK beneficially owned approximately 18.3% of our outstanding capital stock. Pursuant to our strategic alliance with GSK, GSK has the right to license exclusive development and commercialization rights to our product candidates arising from (i) our AT1 Receptor-Neprilysin Inhibitor (ARNI) program for cardiovascular disease and (ii) our MonoAmine Reuptake Inhibitor (MARIN) program for chronic pain. Because GSK is not required to decide whether to license each development program until after we have taken the lead compound in the program thorugh a successful Phase 2 proof-of-concept study, we may be unable to collaborate with other partners with respect to these programs until we have expended substantial resources to advance them through clinical studies. We may not have sufficient funds to pursue such programs in the event GSK does not

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license them at an early stage. Pharmaceutical companies other than GSK that may be interested in developing products with us may be less inclined to do so because of our relationship with GSK, or because of the perception that development programs that GSK does not license, or returns to us, pursuant to our strategic alliance agreement are not promising programs. If our ability to work with present or future strategic partners or collaborators is adversely affected as a result of our strategic alliance with GSK, our business prospects may be limited and our financial condition may be adversely affected which could cause the price of our securities to fall.

If we are unable to enter into future collaboration arrangements or if any such collaborations with third parties are unsuccessful, we will be unable to fully develop and commercialize our product candidates and our business will be adversely affected.

        We have active collaborations with GSK for the RELOVAIR™, LAMA/LABA ('719/VI) and MABA programs and with Astellas for telavancin, and we have licensed our anesthesia compound to AstraZeneca AB (AstraZeneca). Additional collaborations will be needed to fund later-stage development of our product candidates that have not been licensed to a collaborator, and to commercialize these product candidates if approved by the necessary regulatory agencies. Each of TD-5108, our lead compound in the 5-HT₄ program, TD-1792, our investigational antibiotic, and TD-1211, the lead compound in our PµMA program for opioid-induced constipation, has successfully completed a Phase 2 proof-of-concept study, and TD-4208, our LAMA compound that GSK returned to us in February 2009 under the terms of the strategic alliance agreement, has completed a single-dose Phase 1 study. We currently intend to seek third parties with which to pursue collaboration arrangements for the development and commercialization of these compounds. Collaborations with third parties regarding these programs or our other programs may require us to relinquish material rights, including revenue from commercialization of our medicines, on terms that are less attractive than our current arrangements or to assume material ongoing development obligations that we would have to fund. These collaboration arrangements are complex and time-consuming to negotiate, and if we are unable to reach agreements with third-party collaborators, we may fail to meet our business objectives and our financial condition may be adversely affected. We face significant competition in seeking third-party collaborators, especially in the current weak economy, which is driving many biotechnology and biopharmaceutical companies to seek to sell or license their assets. We may be unable to find third parties to pursue product collaborations on a timely basis or on acceptable terms. Furthermore, for any collaboration, we may not be able to control the amount of time and resources that our partners devote to our product candidates and our partners may choose to pursue alternative products. Our inability to successfully collaborate with third parties would increase our development costs and would limit the likelihood of successful commercialization of our product candidates which may cause our stock price to decline.

We depend on third parties in the conduct of our clinical studies for our product candidates.

        We depend on independent clinical investigators, contract research organizations and other third-party service providers in the conduct of our preclinical and clinical studies for our product candidates. We rely heavily on these parties for execution of our preclinical and clinical studies, and control only certain aspects of their activities. Nevertheless, we are responsible for ensuring that our clinical studies are conducted in accordance with good clinical practices (GCPs) and other regulations as required by the FDA and foreign regulatory agencies, and the applicable protocol. Failure by these parties to comply with applicable regulations, GCPs and protocols in conducting studies of our product candidates can result in a delay in our development programs or non-approval of our product candidates by regulatory authorities.

        The FDA enforces good clinical practices and other regulations through periodic inspections of trial sponsors, clinical research organizations (CROs), principal investigators and trial sites. For

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example, in connection with the FDA's review of our telavancin NDAs, the FDA conducted inspections of Theravance and certain of our study sites, clinical investigators and CROs. If we or any of the third parties on which we have relied to conduct our clinical studies are determined to have failed to comply with GCPs, the study protocol or applicable regulations, the clinical data generated in our studies may be deemed unreliable. This could result in non-approval of our product candidates by the FDA, or we or the FDA may decide to conduct additional audits or require additional clinical studies, which would delay our development programs, could result in significant additional costs and could cause the price of our securities to fall.

We face substantial competition from companies with more resources and experience than we have, which may result in others discovering, developing, receiving approval for or commercializing products before or more successfully than we do.

        Our ability to succeed in the future depends on our ability to demonstrate and maintain a competitive advantage with respect to our approach to the discovery and development of medicines. Our objective is to discover, develop and commercialize new small molecule medicines with superior efficacy, convenience, tolerability and/or safety. We expect that any medicines that we commercialize with our collaborative partners will compete with existing or future market-leading medicines.

        Many of our potential competitors have substantially greater financial, technical and personnel resources than we have. In addition, many of these competitors have significantly greater commercial infrastructures than we have. Our ability to compete successfully will depend largely on our ability to leverage our experience in drug discovery and development to:

•

discover and develop medicines that are superior to other products in the market;



•

attract and retain qualified personnel;



•

obtain patent and/or other proprietary protection for our medicines and technologies;



•

obtain required regulatory approvals; and



•

successfully collaborate with pharmaceutical companies in the discovery, development and commercialization of new medicines.

        Established pharmaceutical companies may invest heavily to quickly discover and develop or in-license novel compounds that could make our product candidates obsolete. Accordingly, our competitors may succeed in obtaining patent protection, receiving FDA approval or discovering, developing and commercializing medicines before we do. Other companies are engaged in the discovery of medicines that would compete with the product candidates that we are developing.

        Any new medicine that competes with a generic or proprietary market leading medicine must demonstrate compelling advantages in efficacy, convenience, tolerability and/or safety in order to overcome severe price competition and be commercially successful. VIBATIV™ must demonstrate these advantages, as it competes with vancomycin, a relatively inexpensive generic drug that is manufactured by a number of companies, and a number of existing antibacterial drugs marketed by major and other pharmaceutical companies. If we are not able to compete effectively against our current and future competitors, our business will not grow, our financial condition and operations will suffer and the price of our securities could fall.

        As the principles of multivalency become more widely known, we expect to face increasing competition from companies and other organizations that pursue the same or similar approaches. Novel therapies, such as gene therapy or effective vaccines for infectious diseases, may emerge that will make both conventional and multivalent medicine discovery efforts obsolete or less competitive.

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We have no experience selling or distributing products and no internal capability to do so.

        Generally, our strategy is to engage pharmaceutical or other healthcare companies with an existing sales and marketing organization and distribution system to market, sell and distribute our products. We may not be able to establish these sales and distribution relationships on acceptable terms, or at all. If we receive regulatory approval to commence commercial sales of any of our product candidates that are not covered by our current agreements with GSK, Astellas or AstraZeneca, we will need a partner in order to commercialize such products unless we establish a sales and marketing organization with appropriate technical expertise and supporting distribution capability. At present, we have no sales personnel and a limited number of marketing personnel. Factors that may inhibit our efforts to commercialize our products without strategic partners or licensees include:

•

our inability to recruit and retain adequate numbers of effective sales and marketing personnel;



•

the inability of sales personnel to obtain access to or persuade adequate numbers of physicians to prescribe our products;



•

the lack of complementary products to be offered by sales personnel, which may put us at a competitive disadvantage relative to companies with more extensive product lines; and



•

unforeseen costs and expenses associated with creating an independent sales and marketing organization.

        If we are not able to partner with a third party and are not successful in recruiting sales and marketing personnel or in building a sales and marketing infrastructure, we will have difficulty commercializing our product candidates, which would adversely affect our business and financial condition and which could cause the price of our securities to fall.

If we lose key management or scientific personnel, or if we fail to retain our key employees, our ability to discover and develop our product candidates will be impaired.

        We are highly dependent on principal members of our management team and scientific staff to operate our business. Our company is located in northern California, which is headquarters to many other biotechnology and biopharmaceutical companies and many academic and research institutions. As a result, competition for certain skilled personnel in our market remains intense. None of our employees have employment commitments for any fixed period of time and they all may leave our employment at will. If we fail to retain our remaining qualified personnel or replace them when they leave, we may be unable to continue our development and commercialization activities, which may cause our stock price to decline.

Our business and operations would suffer in the event of system failures.

        Although we have security measures in place, our internal computer systems and those of our CROs and other service providers are vulnerable to damage from computer viruses, unauthorized access, natural disasters, terrorism, war and telecommunication and electrical failures. We have not experienced any material system failure, accident or security breach to date, but if such an event were to occur, it could result in a material disruption to our business. For example, the loss of clinical trial data from completed or ongoing clinical trials of our product candidates could result in delays in our regulatory approval efforts and significantly increase our costs to recover or reproduce the data. If a disruption or security breach results in a loss of or damage to our data or regulatory applications, or inadvertent disclosure of confidential or proprietary information, we could incur liability, the further development of our product candidates could be delayed and the price of our securities could fall.

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Our principal facility is located near known earthquake fault zones, and the occurrence of an earthquake, extremist attack or other catastrophic disaster could cause damage to our facilities and equipment, which could require us to cease or curtail operations.

        Our principal facility is located in the San Francisco Bay Area near known earthquake fault zones and therefore is vulnerable to damage from earthquakes. In October 1989, a major earthquake struck this area and caused significant property damage and a number of fatalities. We are also vulnerable to damage from other types of disasters, including power loss, attacks from extremist organizations, fire, floods, communications failures and similar events. If any disaster were to occur, our ability to operate our business could be seriously impaired. In addition, the unique nature of our research activities and of much of our equipment could make it difficult for us to recover from this type of disaster. We may not have adequate insurance to cover our losses resulting from disasters or other similar significant business interruptions and we do not plan to purchase additional insurance to cover such losses due to the cost of obtaining such coverage. Any significant losses that are not recoverable under our insurance policies could seriously impair our business and financial condition, which could cause the price of our securities to fall.

Risks Related to our Alliance with GSK

GSK's ownership of a significant percentage of our stock and its ability to acquire additional shares of our stock may create conflicts of interest, and may inhibit our management's ability to continue to operate our business in the manner in which it is currently being operated.

        As of February 14, 2011, GSK beneficially owned approximately 18.3% of our outstanding capital stock, and GSK has the right to acquire stock from us to maintain its percentage ownership of our capital stock. GSK could have substantial influence in the election of our directors, delay or prevent a transaction in which stockholders might receive a premium over the prevailing market price for their shares and have significant control over certain changes in our business.

        In addition, GSK may make an offer to our stockholders to acquire outstanding voting stock that would bring GSK's percentage ownership of our voting stock to no greater than 60%, provided that:

•

the offer includes no condition as to financing;



•

the offer is approved by a majority of our independent directors;



•

the offer includes a condition that the holders of a majority of the shares of the voting stock not owned by GSK accept the offer by tendering their shares in the offer; and



•

the shares purchased will be subject to the provisions of the governance agreement on the same basis as the shares of GSK's Class A common stock.

        If pursuant to the provision described above GSK's ownership of us becomes greater than 50.1%, then on or prior to September 1, 2012 GSK is allowed to make an offer to our stockholders to merge with us or otherwise acquire outstanding voting stock that would bring GSK's percentage ownership of our voting stock to 100%, provided that;

•

the offer includes no condition as to financing;



•

the offer is approved by a majority of our independent directors; and



•

the offer includes a condition that the holders of a majority of the shares of the voting stock not owned by GSK accept the offer by tendering their shares in the offer.

        Furthermore, if pursuant to the provision described above GSK's ownership of us is greater than 50.1%, then after September 1, 2012, GSK is allowed to make an offer to our stockholders to acquire

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outstanding voting stock that would bring GSK's percentage ownership of our voting stock to 100%, provided that;

•

the offer includes no condition as to financing;



•

the offer is approved by a majority of our independent directors;



•

the offer includes a condition that the holders of a majority of the shares of the voting stock not owned by GSK accept the offer by tendering their shares in the offer; and



•

the offer is for the greater of (a) the fair market value per share on the date immediately preceding the date of the first public announcement of the offer or (b) $162.75 per share (as adjusted to take into account stock dividends, stock splits, recapitalizations and the like).

        Further, pursuant to our certificate of incorporation, we renounce our interest in and waive any claim that a corporate or business opportunity taken by GSK constitutes a corporate opportunity of ours unless such corporate or business opportunity is expressly offered to one of our directors who is a director, officer or employee of GSK, primarily in his or her capacity as one of our directors.

GSK's rights under the strategic alliance and governance agreements may deter or prevent efforts by other companies to acquire us, which could prevent our stockholders from realizing a control premium.

        Our governance agreement with GSK requires us to exempt GSK from our stockholder rights plan, affords GSK certain rights to offer to acquire us in the event third parties seek to acquire our stock and contains other provisions that could deter or prevent another company from seeking to acquire us. For example, GSK may offer to acquire 100% of our outstanding stock from stockholders in certain circumstances, such as if we are faced with a hostile acquisition offer or if our board of directors acts in a manner to facilitate a change in control of us with a party other than GSK. In addition, pursuant to our strategic alliance agreement with GSK, GSK has the right to license our ARNI program and our MARIN program. As a result of these rights, other companies may be less inclined to pursue an acquisition of us and therefore we may not have the opportunity to be acquired in a transaction that stockholders might otherwise deem favorable, including transactions in which our stockholders might realize a substantial premium for their shares.

GSK could sell or transfer a substantial number of shares of our common stock, which could depress the price of our securities or result in a change in control of our company.

        GSK may sell or transfer our common stock either pursuant to a public offering registered under the Securities Act or pursuant to Rule 144 of the Securities Act. In addition, beginning in September 2012, GSK will have no restrictions on its ability to sell or transfer our common stock on the open market, in privately negotiated transactions or otherwise, and these sales or transfers could create substantial declines in the price of our securities or, if these sales or transfers were made to a single buyer or group of buyers, could contribute to a transfer of control of our company to a third party.

Risks Related to Legal and Regulatory Uncertainty

If our efforts to protect the proprietary nature of the intellectual property related to our technologies are not adequate, we may not be able to compete effectively in our market.

        We rely upon a combination of patents, patent applications, trade secret protection and confidentiality agreements to protect the intellectual property related to our technologies. Any involuntary disclosure to or misappropriation by third parties of this proprietary information could enable competitors to quickly duplicate or surpass our technological achievements, thus eroding our competitive position in our market. The status of patents in the biotechnology and pharmaceutical field involves complex legal and scientific questions and is very uncertain. As of December 31, 2010, we

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owned 228 issued United States patents and 748 granted foreign patents, as well as additional pending United States and foreign patent applications. Our patent applications may be challenged or fail to result in issued patents and our existing or future patents may be invalidated or be too narrow to prevent third parties from developing or designing around these patents. If the sufficiency of the breadth or strength of protection provided by our patents with respect to a product candidate is threatened, it could dissuade companies from collaborating with us to develop, and threaten our ability to commercialize, the product candidate. Further, if we encounter delays in our clinical trials or in obtaining regulatory approval of our product candidates, the patent lives of the related product candidates would be reduced.

        In addition, we rely on trade secret protection and confidentiality agreements to protect proprietary know-how that is not patentable, for processes for which patents are difficult to enforce and for any other elements of our drug discovery and development processes that involve proprietary know-how, information and technology that is not covered by patent applications. Although we require our employees, consultants, advisors and any third parties who have access to our proprietary know-how, information and technology to enter into confidentiality agreements, we cannot be certain that this know-how, information and technology will not be disclosed or that competitors will not otherwise gain access to our trade secrets or independently develop substantially equivalent information and techniques. Further, the laws of some foreign countries do not protect proprietary rights to the same extent as the laws of the United States. As a result, we may encounter significant problems in protecting and defending our intellectual property both in the United States and abroad. If we are unable to prevent material disclosure of the intellectual property related to our technologies to third parties, we will not be able to establish or, if established, maintain a competitive advantage in our market, which could materially adversely affect our business, financial condition and results of operations, which could cause the price of our securities to fall.

Litigation or third-party claims of intellectual property infringement would require us to divert resources and may prevent or delay our drug discovery and development efforts.

        Our commercial success depends in part on us and our partners not infringing the patents and proprietary rights of third parties. Third parties may assert that we or our partners are using their proprietary rights without authorization. There are third party patents that may cover materials or methods for treatment related to our product candidates. At present, we are not aware of any patent claims with merit that would adversely and materially affect our ability to develop our product candidates, but nevertheless the possibility of third party allegations cannot be ruled out. In addition, third parties may obtain patents in the future and claim that use of our technologies infringes upon these patents. Furthermore, parties making claims against us or our partners may obtain injunctive or other equitable relief, which could effectively block our ability to further develop and commercialize one or more of our product candidates. For example, an action has been filed in the United States Patent and Trademark Office opposing registration of the trademark VIBATIV™. Failure to register this trademark may have an adverse impact on sales of VIBATIV™, which could adversely affect our business. Defense of these claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of employee resources from our business.

        In the event of a successful claim of infringement against us, we may have to pay substantial damages, obtain one or more licenses from third parties or pay royalties. In addition, even in the absence of litigation, we may need to obtain licenses from third parties to advance our research or allow commercialization of our product candidates, and we have done so from time to time. We may fail to obtain any of these licenses at a reasonable cost or on reasonable terms, if at all. In that event, we would be unable to further develop and commercialize one or more of our product candidates, which could harm our business significantly. In addition, in the future we could be required to initiate litigation to enforce our proprietary rights against infringement by third parties. Prosecution of these

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claims to enforce our rights against others would involve substantial litigation expenses and divert substantial employee resources from our business. If we fail to effectively enforce our proprietary rights against others, our business will be harmed, which may cause our stock price to decline.

If the efforts of our partner, GSK, to protect the proprietary nature of the intellectual property related to the assets in the LABA collaboration, including RELOVAIR™ and LAMA/LABA ('719/VI), are not adequate, the future commercialization of any medicines resulting from the LABA collaboration could be delayed or prevented, which would materially harm our business and could cause the price of our securities to fall.

        The risks identified in the two preceding risk factors also apply to the intellectual property protection efforts of our partner GSK. To the extent the intellectual property protection of any of the assets in the LABA collaboration are successfully challenged or encounter problems with the United States Patent and Trademark Office or other comparable agencies throughout the world, the future commercialization of these potential medicines could be delayed or prevented. Any challenge to the intellectual property protection of a late-stage development asset arising from the LABA collaboration could harm our business and cause the price of our securities to fall.

Product liability lawsuits could divert our resources, result in substantial liabilities and reduce the commercial potential of our medicines.

        The risk that we may be sued on product liability claims is inherent in the development and commercialization of pharmaceutical products. Side effects of, or manufacturing defects in, products that we or our partners develop or commercialize could result in the deterioration of a patient's condition, injury or even death. Once a product is approved for sale and commercialized, the likelihood of product liability lawsuits tends to increase. Our partner Astellas launched VIBATIV™, our first approved product, in the U.S. in November 2009. Claims may be brought by individuals seeking relief for themselves or by individuals or groups seeking to represent a class. These lawsuits may divert our management from pursuing our business strategy and may be costly to defend. In addition, if we are held liable in any of these lawsuits, we may incur substantial liabilities and may be forced to limit or forgo further commercialization of the applicable products.

        Although we maintain general liability and product liability insurance, this insurance may not fully cover potential liabilities. In addition, inability to obtain or maintain sufficient insurance coverage at an acceptable cost or to otherwise protect against potential product liability claims could prevent or inhibit the commercial production and sale of our products, which could adversely affect our business. Product liability claims could also harm our reputation, which may adversely affect our and our partners' ability to commercialize our products successfully, which could cause the price of our securities to fall.

Government restrictions on pricing and reimbursement, as well as other healthcare payor cost-containment initiatives, may negatively impact our ability to generate revenues.

        The continuing efforts of the government, insurance companies, managed care organizations and other payors of health care costs to contain or reduce costs of health care may adversely affect one or more of the following:

•

our or our collaborators' ability to set a price we believe is fair for our products, if approved;



•

our ability to generate revenues and achieve profitability; and



•

the availability of capital.

        The Patient Protection and Affordable Care Act and other potential legislative or regulatory action regarding healthcare and insurance matters, along with the trend toward managed healthcare in the United States, could influence the purchase of healthcare products and reduce demand and prices for our products, if approved. This could harm our or our collaborators' ability to market our potential

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medicines and generate revenues. Cost containment measures that health care payors and providers are instituting and the effect of the Patient Protection and Affordable Care Act and further agency regulations that are likely to emerge in connection with the passage of this act could significantly reduce potential revenues from the sale of any product candidates approved in the future. In addition, in certain foreign markets, the pricing of prescription drugs is subject to government control and reimbursement may in some cases be unavailable. We believe that pricing pressures at the state and federal level, as well as internationally, will continue and may increase, which may make it difficult for us to sell our potential medicines that may be approved in the future at a price acceptable to us or our collaborators, which may cause our stock price to decline.

If we use hazardous and biological materials in a manner that causes injury or violates applicable law, we may be liable for damages.

        Our research and development activities involve the controlled use of potentially hazardous substances, including chemical, biological and radioactive materials. In addition, our operations produce hazardous waste products. Federal, state and local laws and regulations govern the use, manufacture, storage, handling and disposal of hazardous materials. We may incur significant additional costs to comply with these and other applicable laws in the future. Also, even if we are in compliance with applicable laws, we cannot completely eliminate the risk of contamination or injury resulting from hazardous materials and we may incur liability as a result of any such contamination or injury. In the event of an accident, we could be held liable for damages or penalized with fines, and the liability could exceed our resources. We do not have any insurance for liabilities arising from hazardous materials. Compliance with applicable environmental laws and regulations is expensive, and current or future environmental regulations may impair our research, development and production efforts, which could harm our business, which could cause the price of our securities to fall.

Risks Related to Ownership of our Common Stock

The price of our securities has been extremely volatile and may continue to be so, and purchasers of our securities could incur substantial losses.

        The price of our securities has been extremely volatile and may continue to be so. The stock market in general and the market for biotechnology and biopharmaceutical companies in particular have experienced extreme volatility that has often been unrelated to the operating performance of particular companies, in particular during the last few years. The following factors, in addition to the other risk factors described in this section, may also have a significant impact on the market price of our securities:

•

any adverse developments or results or perceived adverse developments or results with respect to the RELOVAIR™ program with GSK, including, without limitation, any difficulties or delays encountered with regard to the regulatory path for the RELOVAIR™ program, delays in completing the various Phase 3 studies or any indication from the Phase 3 clinical studies that RELOVAIR™ is not safe or efficacious;



•

any adverse developments or results or perceived adverse developments or results with respect to the LAMA/LABA ('719/VI) program with GSK, including, without limitation, any difficulties or delays encountered with regard to the regulatory path for the '719/VI program, delays in initiating or completing the Phase 3 studies or any indication from the Phase 3 clinical studies that '719/VI is not safe or efficacious;



•

any adverse developments or results or perceived adverse developments or results with respect to the MABA program with GSK, including without limitation any indication from the Phase 2b and other clinical and preclinical studies of '081 that the compound is not safe or efficacious;

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•

any adverse developments or perceived adverse developments with respect to the commercialization of VIBATIV™, including any failure to meet market expectations with respect to the timing and volume of sales of VIBATIV™;



•

any adverse developments or perceived adverse developments with respect to regulatory matters concerning telavancin in any foreign jurisdiction, in particular the European Medicines Agency's review of the MAA, which we currently anticipate will be completed in the first half of 2011;



•

any further adverse developments or perceived adverse developments with respect to our telavancin NP NDA, which the FDA has determined cannot be approved without data from additional clinical studies;



•

any adverse developments or perceived adverse developments in the field of LABAs, including any change in FDA policy or guidance (such as the pronouncement in February 2010 warning that LABAs should not be used alone in the treatment of asthma and related labeling requirements or the impact of the March 2010 FDA Advisory Committee discussing LABA clinical trial design to evaluate serious asthma outcomes);



•

announcements regarding GSK's decisions whether or not to license any of our development programs or to return to us any previously licensed program, such as its recent decision not to license our PµMA program;



•

GSK's decisions whether or not to purchase from us, on a quarterly basis, sufficient shares of common stock to maintain its ownership percentage taking into account our preceding quarter's option exercise and equity vesting activity;



•

any announcements of developments with, or comments by, the FDA or other regulatory agencies with respect to products we or our partners have under development or have commercialized;



•

our incurrence of expenses in any particular quarter in excess of market expectations;



•

the extent to which GSK advances (or does not advance) product candidates arising from our LABA collaboration or licensed from us under the strategic alliance agreement through development into commercialization;



•

any adverse developments or perceived adverse developments with respect to our relationship with GSK, including without limitation, disagreements that may arise between us and GSK concerning the public announcement of data (both timing and content) from the RELOVAIR™ and '719/VI Phase 3 programs;



•

any adverse developments or perceived adverse developments with respect to our relationship with Astellas, including without limitation, disagreements that may arise between us and Astellas concerning regulatory strategy or further development of telavancin, or Astellas' termination of our telavancin license, development and commercialization agreement;



•

any adverse developments or perceived adverse developments with respect to our partnering efforts with our 5-HT₄ program, PµMA program, TD-1792 or TD-4208;



•

announcements regarding GSK or Astellas generally;



•

announcements of patent issuances or denials, technological innovations or new commercial products by us or our competitors;



•

developments concerning any collaboration we may undertake with companies other than GSK or Astellas;

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•

publicity regarding actual or potential study results or the outcome of regulatory review relating to products under development by us, our partners or our competitors;



•

regulatory developments in the United States and foreign countries;



•

economic and other external factors beyond our control;



•

sales of stock by us or by our stockholders, including sales by certain of our employees and directors whether or not pursuant to written pre-determined selling plans under Rule 10b5-1 of the Securities Exchange Act of 1934, some of which plans are currently in effect, such as plans adopted by our employees to sell shares to cover taxes due upon the quarterly vesting of restricted stock units and plans adopted by certain of our executive officers and directors to sell shares in connection with the exercise of stock options that are nearing their expiration, and other plans that may be entered into;



•

relative illiquidity in the public market for our common stock (our six largest stockholders other than GSK collectively owned approximately 48.6% of our outstanding capital stock as of February 14, 2011); and



•

potential sales or purchases of our capital stock by GSK.

Concentration of ownership will limit your ability to influence corporate matters.

        As of February 14, 2011, GSK beneficially owned approximately 18.3% of our outstanding capital stock and our directors, executive officers and investors affiliated with these individuals beneficially owned approximately 7.7% of our outstanding capital stock. Based on our review of publicly available filings as of February 14, 2011, our six largest stockholders other than GSK collectively owned approximately 48.6% of our outstanding capital stock. These stockholders could control the outcome of actions taken by us that require stockholder approval, including a transaction in which stockholders might receive a premium over the prevailing market price for their shares.

Anti-takeover provisions in our charter and bylaws, in our rights agreement and in Delaware law could prevent or delay a change in control of our company.

        Provisions of our certificate of incorporation and bylaws may discourage, delay or prevent a merger or acquisition that stockholders may consider favorable, including transactions in which you might otherwise receive a premium for your shares. These provisions include:

•

requiring supermajority stockholder voting to effect certain amendments to our certificate of incorporation and bylaws;



•

restricting the ability of stockholders to call special meetings of stockholders;



•

prohibiting stockholder action by written consent; and



•

establishing advance notice requirements for nominations for election to the board of directors or for proposing matters that can be acted on by stockholders at stockholder meetings.

        In addition, our board of directors has adopted a rights agreement that may prevent or delay a change in control of us. Further, some provisions of Delaware law may also discourage, delay or prevent someone from acquiring us or merging with us.

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ITEM 1B.    UNRESOLVED STAFF COMMENTS

        None.

ITEM 2.    PROPERTIES

        Our headquarters are located in South San Francisco, CA, and consist of two leased buildings of approximately 110,000 and 60,000 square feet. We entered into amendments to the leases in June 2010 to extend the lease terms through May 2020 and we may extend the terms for two additional five-year periods. The current annual rental expense under these leases is approximately $6.8 million. As security for performance of certain obligations under the facility operating leases for our headquarters, we were required to have a financial institution issue letters of credit in the aggregate of approximately $0.8 million, which we have collateralized with the financial institution by an equal amount of restricted cash.

ITEM 3.    LEGAL PROCEEDINGS

        We are not a party to any material legal proceedings.

PART II

ITEM 5.    MARKET FOR REGISTRANT'S COMMON EQUITY, RELATED STOCKHOLDER MATTERS AND ISSUER PURCHASES OF EQUITY SECURITIES

        Our common stock has been traded on the Nasdaq Global Market under the symbol "THRX" since October 5, 2004. The following table sets forth the high and low closing prices of our common stock on a per share basis for the periods indicated and as reported on the Nasdaq Global Market:

        As of February 14, 2011, there were 188 stockholders of record of our common stock. There is no established public trading market for our Class A common stock, all of which is owned by GSK. On November 29, 2010 we sold 5,750,000 shares of our common stock to an affiliate of GSK in a private placement for an aggregate purchase price of $129.4 million. We issued and sold the shares in reliance upon an exemption from registration pursuant to Section 4(2) of the Securities Act of 1933, as amended.

Dividend Policy

        We currently intend to retain any future earnings to finance our research and development efforts. We have never declared or paid cash dividends and do not intend to declare or pay cash dividends on our common stock or Class A common stock in the foreseeable future.

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Equity Compensation Plans

        The following table provides certain information with respect to all of our equity compensation plans in effect as of December 31, 2010:

        The Theravance, Inc. 2008 New Employee Equity Incentive Plan (2008 Plan) is a non-stockholder approved plan, which was adopted by the board of directors (Board) on January 29, 2008 and is intended to satisfy the requirements of Nasdaq Marketplace Rule 5635(c)(4). Non-statutory options, restricted stock units, and restricted stock awards were granted under the 2008 Plan to our newly hired employees until April 27, 2010, the date on which stockholders approved our amended and restated 2004 Equity Incentive Plan. No further awards will be granted under the 2008 Plan. The Board authorized 500,000 shares of common stock for issuance under the 2008 Plan upon its adoption in 2008 and the Compensation Committee of the Board authorized an additional 200,000 shares for issuance under the 2008 Plan in July 2009. All option grants have an exercise price per share of no less than 100% of the fair market value per share of common stock on the grant date. Additional features of the 2008 Plan are outlined in Note 11 to the Consolidated Financial Statements.

Stock Performance Graph

        The graph set forth below compares the cumulative total stockholder return on our common stock for the period commencing on December 31, 2005 and ending on December 31, 2010, with the cumulative total return of (i) the Nasdaq Composite Index and (ii) the NYSE Arca Biotechnology Index, over the same period. This graph assumes the investment of $100.00 on December 31, 2005 in each of (1) our common stock, (2) the Nasdaq Composite Index and (3) the NYSE Arca Biotechnology Index, and assumes the reinvestment of dividends, if any, although dividends have never been declared on our common stock.

        The comparisons shown in the graph below are based upon historical data. We caution that the stock price performance shown in the graph below is not necessarily indicative of, nor is it intended to forecast, the potential future performance of our common stock. Information used in the graph was

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obtained from Research Data Group, Inc., a source believed to be reliable, but we are not responsible for any errors or omissions in such information.

        Notwithstanding anything to the contrary set forth in any of our previous or future filings under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended, that might incorporate this Annual Report on Form 10-K or future filings made by us under those statutes, this Stock Performance Graph section shall not be deemed filed with the United States Securities and Exchange Commission and shall not be deemed incorporated by reference into any of those prior filings or into any future filings made by us under those statutes.

COMPARISON OF 5 YEAR CUMULATIVE TOTAL RETURN*
Among Theravance, Inc., The NASDAQ Composite Index
And The NYSE Arca Biotechnology Index

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*

100 invested on 12/31/05 in stock or index, including reinvestment of dividends. Fiscal year ending December 31.

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ITEM 6.    SELECTED FINANCIAL DATA

        The following tables reflect selected consolidated summary financial data for each of the last five fiscal years and are derived from our audited financial statements. This data should be read in conjunction with Item 8, "Financial Statements and Supplementary Data", and with Item 7, "Management's Discussion and Analysis of Financial Condition and Results of Operations" in this Annual Report on Form 10-K.

 

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