Acceleron Pharma Announces Joint Development and Commercialization Agreement with Shire on Novel Muscle Therapeutics for Orphan

Acceleron Pharma Announces Joint Development and Commercialization Agreement with Shire on Novel Muscle Therapeutics for Orphan Diseases
$498 Million Deal Grants Shire Exclusive Ex-North American Rights to Acceleron's Innovative Class of ActRIIB Molecules Including ACE-031, Currently in Phase 2 Trials to Treat Patients with Duchenne Muscular Dystrophy

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Acceleron Pharma, Inc., a biopharmaceutical company developing novel therapeutics that modulate the growth of cells and tissues including muscle, bone, fat, red blood cells and the vasculature, and Shire plc (LSE: SHP, NASDAQ: SHPGY), the global specialty biopharmaceutical company, today announced a joint development and commercialization agreement for ACE-031 and other novel molecules targeting the activin receptor type IIB (ActRIIB) pathway. This pathway plays critical roles in regulating the growth of skeletal muscle.

Shire will receive an exclusive license to Acceleron's ActRIIB molecules, including ACE-031, in markets outside of North America. Acceleron will retain all commercial rights in North America. The collaboration will initially investigate ACE-031, Acceleron's lead ActRIIB drug candidate, currently in a Phase 2a trial for the treatment of patients with Duchenne Muscular Dystrophy (DMD). DMD is a fatal orphan muscle disease with no currently approved treatment. ACE-031 and other ActRIIB molecules also have the potential to be used in other muscular and neuromuscular disorders with high unmet medical need.

Shire and Acceleron will jointly collaborate on a worldwide development program to advance ACE-031 into a global Phase 2/3 clinical program designed to demonstrate disease modification in DMD patients. Shire will utilize its Lexington manufacturing facility to produce commercial supplies of the product for both parties. If marketing authorization is received, Acceleron will commercialize ACE-031 in the U.S. and Canada, and Shire will commercialize the therapy in the rest of the world.

Under the terms of the agreement, Shire will make an upfront cash payment to Acceleron of $45 million. Acceleron is eligible to receive additional development, regulatory and sales milestone payments of up to $165 million for ACE-031 in DMD, up to an additional $288 million for other indications and molecules, and royalty payments on product sales. Shire and Acceleron will share development costs in North America and Europe, and Shire will be responsible for development costs in other markets.

"The structure of this collaboration allows Acceleron to retain commercial rights in North America with the opportunity to build a highly valuable business while collaborating with an ideal partner for ACE-031," said John Knopf, Ph.D., Chief Executive Officer of Acceleron. "Shire's international presence and their proven leadership and dedicated focus on orphan diseases forms the basis for a successful collaboration that will bring innovative therapies to patients with enormous unmet medical need."

"This collaboration is an excellent strategic fit to the work that Shire is already doing on behalf of patients with rare diseases," said Sylvie Grégoire, President of Shire Human Genetic Therapies. "Working with Acceleron on the development of ACE-031 for DMD allows us to use our expertise to help patients suffering from this devastating disease, and expands our pipeline into a new therapeutic area."

About Duchenne Muscular Dystrophy (DMD)

DMD is a debilitating and fatal genetic disorder characterized by the progressive loss of muscle strength and function. It primarily affects boys and occurs in approximately 1 in every 3,500 male births. DMD is caused by genetic mutations that result in the absence of dystrophin, a protein necessary to maintain the structural integrity of muscle fibers. This condition leads to damage and deterioration of skeletal and cardiac muscles, which eventually become infiltrated by non-functional scar and fatty tissue. As a result, patients experience a relentless decline in muscle strength that impairs their ability to walk, breathe and live independently. Many patients spend the majority of their lives using wheelchairs and eventually lose upper body function as well. Few patients survive beyond their late-20s when their heart and respiratory muscles weaken and eventually fail.

About ACE-031

ACE-031 is an investigational protein therapeutic designed to build muscle and increase strength by inhibiting signaling through a cell surface receptor called activin receptor type IIB (ActRIIB). ACE-031 is a recombinant fusion protein that is produced by joining a portion of the human ActRIIB receptor to a portion of a human antibody. This creates a freely circulating, decoy version of ActRIIB which interferes with proteins, such as GDF-8 (myostatin), that normally limit the growth and regeneration of muscle by binding to and activating endogenous ActRIIB. Recent studies with ACE-031 suggest that blocking signaling through ActRIIB may be a way to increase muscle mass and improve physical function. In a range of animal models of muscle disease, including models of muscular dystrophy, muscle loss related to corticosteroid treatment, androgen deprivation or advanced age, ACE-031 increased muscle mass, strength and physical function. Unlike the mutation-specific RNA-based therapeutics in clinical development for DMD, ACE-031 could potentially benefit all patients with DMD, irrespective of the underlying genetic mutation.

About Shire PLC

Shire's strategic goal is to become the leading specialty biopharmaceutical company that focuses on meeting the needs of the specialist physician. Shire focuses its business on attention deficit hyperactivity disorder (ADHD), human genetic therapies (HGT) and gastrointestinal (GI) diseases as well as opportunities in other therapeutic areas to the extent they arise through acquisitions. Shire's in-licensing, merger and acquisition efforts are focused on products in specialist markets with strong intellectual property protection and global rights. Shire believes that a carefully selected and balanced portfolio of products with strategically aligned and relatively small-scale sales forces will deliver strong results.

For further information on Shire, please visit the Company's website: www.shire.com.

About Acceleron Pharma

Acceleron is a privately held biopharmaceutical company committed to discover, develop, manufacture and commercialize novel biotherapeutics that modulate the growth of red blood cells, bone, muscle, fat and the vasculature to treat musculoskeletal, metabolic and cancer-related diseases. Acceleron's scientific approach takes advantage of its unique insight into the regenerative powers of the TGF-β superfamily of proteins. Acceleron utilizes proven biotherapeutic technologies and capitalizes on the company's internal GMP manufacturing capability to rapidly and efficiently advance its therapeutic programs. The investors in Acceleron include Advanced Technology Ventures, Alkermes, Bessemer Ventures, Celgene, Flagship Ventures, MPM BioEquities, OrbiMed Advisors, Polaris Ventures, QVT Financial, Sutter Hill Ventures and Venrock.

For further information on Acceleron Pharma, please visit www.acceleronpharma.com.

Contacts
Acceleron Pharma:
Steven Ertel, 617-649-9234
Vice President, Corporate Development