Ipsen bags Blueprint drug to move deeper into ultra-rare disease

Ipsen has struck a deal with Blueprint Medicines to add another treatment for fibrodysplasia ossificans progressiva (FOP) to its rare disease pipeline. The backloaded, $535 million (€485 million) deal comes months after Ipsen paid $1 billion to buy Clementia Pharmaceuticals for an FOP therapy. 

In return for $25 million upfront and many times that in milestones, Ipsen has secured global rights to an ALK2 inhibitor from Blueprint. ALK2 is the genetic driver of FOP. The drug, BLU-782, entered phase 1 testing in healthy subjects earlier this year on the strength of preclinical data suggesting it can prevent heterotopic ossification and otherwise improve outcomes in FOP patients.

The deal sees Ipsen double up in an ultra-rare disease that causes bone to form in connective tissues, adding BLU-782 to a pipeline that already features RARγ agonist palovarotene. Ipsen’s desire to have two FOP therapies is, in part, a reflection of its belief that the assets are complementary.

“Ipsen plans to commence a potentially pivotal phase 2 trial during 2020E as monotherapy. Ipsen also has plans to combine BLU-782 with its FOP lead asset palovarotene, acquired via Clementia,” analysts at Jefferies wrote in a note to investors. 

Regeneron has a FOP treatment, REGN2477, in the clinic, but Ipsen’s back-to-back deals give it the broadest suite of drug options in the niche. Whether that translates into significant sales remains to be seen.

Ipsen thinks palovarotene can rack up peak sales in FOP of $400 million, but the patient population is tiny. According to the International Fibrodysplasia Ossificans Progressiva Association, there have been 800 confirmed cases of FOP globally. Around one-third of the known cases are in the U.S.

If everything goes to plan, Ipsen will win U.S. approval for palovarotene in flare-up patients next year and add chronic treatment to its label in 2021. However, palovarotene fell short of analyst expectations in phase 2, reducing new heterotopic ossification by about 73%.

Editor's note: The phase 2 heterotopic ossification figure in this story has been corrected.