Acceleron takes back drug rights from Celgene to start pulmonary push

CEO says drug could be first disease-modifying drug for pulmonary arterial hypertension.

Acceleron's long-running collaboration with Celgene on sotatercept has taken another turn today, with an amendment of their agreement to give Acceleron the right to develop the drug for pulmonary diseases.

Acceleron, which is hosting an event with analysts today to highlight its R&D portfolio, said it plans to start a phase 2 trial of sotatercept (ACE-011) in pulmonary arterial hypertension (PAH) in the first half of 2018.

The biopharma's CEO Habib Dable told analysts that PAH has a high unmet need, with around 30,000 patients in the U.S. alone and no disease-modifying treatment approved, with most therapies focused on dilating the blood vessels to alleviate symptoms. Sotatercept could become the first disease-modifying therapy for PAH, which typically strikes in middle age and has an average survival of just five to seven years.

"Sotatercept will be the lead family in our new pulmonary disease franchise," he said, adding that this will sit alongside its established hematology and neuromuscular programs. The company plans to have three programs in phase 3 development in the next three years—in other words, by the end of 2020.

With sotatercept, Acceleron gets a phase 2-ready project with clinical experience in 300 patients to date, said a spokesman for the company. Celgene has retained rights in non-pulmonary diseases and will get royalties on sales in pulmonary indications in the low 20s if sotatercept reaches the market.

"While many therapies are approved for the treatment of pulmonary arterial hypertension, these therapies all focus on a mechanism of vasodilation and the prognosis for patients remains poor," said Eric Austin, M.D., director of the Vanderbilt Pediatric Pulmonary Hypertension Program.

"Sotatercept's mechanism is intended to rectify the deficits in molecular signaling that underlie both the familial and idiopathic forms of this disease."

Celgene first licensed the TGF-beta superfamily-targeting drug in 2008, and in 2011 negotiated rights to another Acceleron-developed drug in the class—luspatercept (ACE-536)—which has now taken precedence in its clinical pipeline (PDF) with sotatercept not listed.

Luspatercept is in phase 3 trials for myelodysplastic syndromes and beta-thalassemia, and will remain "our number one priority for the next three years," said Dable, with the potential to be a multibillion-dollar product with potentially seven programs in phase 2 and 3 in 2018. The company is anticipating the first phase 3 results for the drug next year with a possible market entry in 2019.

In the neuromuscular category, Acceleron has another TGF beta-targeting drug, ACE-083, in phase 2 trials for focal muscle diseases such as facioscapulohumeral muscular dystrophy (FSHD), as well as ACE-2494, which is due to enter the clinic later this year and is being cued up for development in FSHD as well as other diseases like amyotrophic lateral sclerosis (ALS) and Duchenne muscular dystrophy (DMD).

Shares in Acceleron plummeted in June after a failed phase 2 trial of its advanced renal cell carcinoma candidate dalantercept led to the abandonment of the candidate.