FDA Approves Regeneron’s Pasatru for Adults with Rare Genetic Disorder

BCW member Regeneron has reached a significant milestone in rare-disease treatment with U.S. Food and Drug Administration approval of Pasatru™ (garetosmab-grts), a new therapy for adults living with fibrodysplasia ossificans progressiva (FOP). The treatment is the first FDA-approved therapy shown in a placebo-controlled trial to reduce both the formation of new heterotopic ossification (HO) lesions and clinician-assessed flare-ups in adults with the ultra-rare condition.

FOP is a progressive genetic disorder in which abnormal bone forms within muscles, tendons, ligaments and other connective tissues. Over time, this rogue bone growth can severely restrict movement and make everyday activities such as walking, eating, speaking and even breathing increasingly difficult. Approximately 900 people worldwide have been diagnosed with the condition, and many patients become wheelchair-dependent by age 30.

Regeneron’s newly approved Pasatru works by blocking Activin A, a protein that Regeneron scientists discovered plays a critical role in the development of abnormal bone lesions in people with FOP. The fully human monoclonal antibody is administered intravenously once every four weeks and can be provided in a variety of care settings, including through home infusion when appropriate.

The FDA’s decision was supported by results from Regeneron’s Phase 3 OPTIMA clinical trial involving 63 adults with FOP. After 56 weeks, participants receiving the two studied doses of Pasatru experienced reductions of 90% and 94% in the total number of new HO lesions compared with those receiving a placebo. The 10 mg/kg treatment group also experienced an 88% reduction in clinician-assessed flare-ups compared with placebo.

“The approval of Pasatru is the culmination of decades of pioneering research that Regeneron has pursued alongside the FOP community, rooted in our discovery of the role that Activin A plays in driving this disease,” said George D. Yancopoulos, M.D., Ph.D., Board co-Chair, President and Chief Scientific Officer at Regeneron. He called the approval an important reflection of the company’s broader commitment to developing new treatment options for people facing rare diseases with limited therapeutic choices.

The company’s work on FOP is continuing. A Phase 3 study known as OPTIMA 2, which will evaluate Pasatru in adolescents and children with FOP, is planned to begin later this year. Regeneron has also submitted Pasatru for regulatory review in the European Union, with additional submissions planned in other countries, including Japan.

Headquartered in Tarrytown, Regeneron is a leading biotechnology company focused on discovering, developing and commercializing medicines for serious diseases. Its research and development efforts span areas including cancer, eye diseases, allergic and inflammatory diseases, cardiovascular and metabolic conditions, neurological and hematologic diseases, infectious diseases and rare disorders.

For the BCW, the FDA approval marks another noteworthy achievement by a member company whose scientific research and innovation are helping advance the life sciences sector while addressing some of the most challenging unmet needs facing patients and families.

You can read their full press release here.