REGN2477 is an investigational drug product for FOP from Regeneron. REGN2477 is an antibody to Activin A, which is believed to play a significant role in developing heterotopic ossification (HO). By blocking Activin A, REGN2477 may slow or prevent the formation of new HO.
The primary goal of this Phase 2 trial is to assess the safety, tolerability and effects of REGN2477 on HO formation in adult males and females with FOP.
REGN2477 has completed a Phase 1 study looking at the safety of the drug in healthy volunteers. Based upon the Phase 1 study, as well as preclinical animal data, Regeneron is now assessing REGN2477 in people with FOP. Regeneron received Fast Track Designation from the U.S. Food & Drug Administration (FDA) for REGN 2477. Fast Track Designation allows for companies to have more frequent engagement with the FDA and allows a company to be eligible for accelerated approval/priority review (a 6-month review timeline).
The REGN2477 Phase 2 trial is a placebo-controlled, multi-national study. Enrolled subjects will receive REGN2477 or placebo (no active drug) monthly by intravenous infusion for 6 months. Then all participants will receive REGN2477 for 6 months.
The data from the Phase 2 trial may be used to support starting a Phase 3 study for REGN2477.
Frequently Asked Questions
Who is eligible to participate in Regeneron’s Phase 2 trial?
The Phase 2 trial is open to men and women ages 18-60 who have a clinical diagnosis of the classic FOP mutation (R206H mutation). Participants need to have had FOP disease activity within one year of the screening visit. FOP disease activity is defined as pain, swelling, stiffness, and other signs and symptoms associated with FOP flare-ups; or worsening of joint function, or radiographic progression of heterotopic ossifications (increase in site or number of HO lesions) with/without being associated with flare-up episodes. Additional exclusion criteria regarding medical history, medication use, allergies, and laboratory values are available at clinicaltrials.gov.
Can children participate in the Regeneron Phase 2 trial?
The current trial is not open to individuals with FOP under the age 18. Many treatments are first studied in adults to establish the therapy’s safety profile before studying in children.
How many people can participate in the trial?
Up to 40 people will be enrolled into the Phase 2 study with the expectation that 24 individuals will have active heterotopic ossification and will be able to enroll in the trial.
How many will be on placebo vs actual study drug?
Half or up to 20 people will randomly be given the REGN2477 drug and half will be given placebo (i.e. no active drug) for the first 6 months. At the end of the first 6 months, all participants will have the opportunity to receive REGN2477. So, half of the study participants will receive 12 months of REGN2477 while the other half will receive 6 months of REGN2477 (after 6 months of placebo).
How long does the Regeneron’s Phase 2 trial last?
This trial is a two-period study design consisting of a 6-month placebo-drug treatment period (period 1) followed by a 6-month treatment period with all participants receiving drug (period 2). There is a 24 week follow-up period after period 2 is complete, making the total trial 76 weeks long.
What centers and locations will be involved in the REGN2477 trial?
Regeneron is currently in the process of identifying centers to participate in the Phase 2 study. Please refer to clinicaltrials.gov for the latest information on clinical sites.
How is REGN2477 given to people with FOP?
REGN2477 is taken by IV infusion (i.e. given through the vein) every 4 weeks.
What clinical data currently exists for REGN2477?
The safety of REGN2477 has been studied in healthy volunteers who do not have FOP. The Phase 2 trial will be the first study of REGN2477 in individuals with FOP.
What are the travel commitments and requirements to participate in the trial?
Individuals who participate in the REGN2477 trial will receive further information about their travel commitments and study reimbursement.
Who do I contact if I’m interested in learning more about Regeneron’s trial?
Have your doctor connect with Regeneron through one of the resources below:
- Regeneron Website for FOP Researchers and Physicians: ActivinAandFOP.com
- Medical Information Hotline: