Regeneron team IDs a candidate for ultra-rare bone disease

Aris Economides

A fast-growing Regeneron ($REGN) says a team of top researchers has identified a clear target for a rare genetic bone disease. And they have an antibody in preclinical testing that could correct the disorder.

Fibrodysplasia ossificans progressiva, or FOP, is a genetic disease that triggers the conversion of muscle and other tissue into bone. The way Regeneron explains it, the disease is triggered by mutations in ACVR1, a gene that encodes for the ACVR1 receptor protein. The ligand Activin-A typically interacts with the ACVR1 gene to regulate bone growth, turning off signaling of bone morphogenetic proteins. But the process--confirmed in a mouse model the investigators created--is skewed by the genetic mutation, causing the bone morphogenetic proteins to switch on rather than switch off, turning soft tissue into bone.

There are some 800 known cases in the world, with 200 of those cases in the U.S.

To counter the cascade of events, the Regeneron team used the company's antibody development platform, VelocImmune, to come up with a way to block Activin-A, shutting down the process. 

"Gaining insight into the Activin A-related mechanism is a tremendous step forward for researchers, and the knowledge gained about receptor-ligand interactions and signaling in this system may prove relevant in other diseases, as well," says Aris Economides, who co-founded the genetics center in Tarrytown, NY.

Regeneron has benefited from the rapid growth of Eylea sales and recently earned a blockbuster approval for a new PCSK9 cholesterol drug, which is partnered with Sanofi ($SNY).

Back at the beginning of 2014 the biotech revealed that it had been developing a new genetics research center. While this study was not connected to the new center, it does reflect the keen interest the company has in the field. Regeneron seems determined to have a full pipeline that extends from preclinical research all the way through new studies on approved treatments. And it's been investing a significant part of its revenue to accomplish that goal.

- here's the release (PDF)