{"id":1009321,"date":"2026-10-12T12:09:07","date_gmt":"2026-10-12T16:09:07","guid":{"rendered":"https:\/\/www.marketnewsdesk.com\/index.php\/pasatru-garetosmab-grts-demonstrates-zero-new-heterotopic-ossification-ho-lesions-in-adult-fibrodysplasia-ossificans-progressiva-fop-patients-during-optima-trial-extension\/"},"modified":"2026-10-12T12:09:07","modified_gmt":"2026-10-12T16:09:07","slug":"pasatru-garetosmab-grts-demonstrates-zero-new-heterotopic-ossification-ho-lesions-in-adult-fibrodysplasia-ossificans-progressiva-fop-patients-during-optima-trial-extension","status":"publish","type":"post","link":"https:\/\/www.marketnewsdesk.com\/index.php\/pasatru-garetosmab-grts-demonstrates-zero-new-heterotopic-ossification-ho-lesions-in-adult-fibrodysplasia-ossificans-progressiva-fop-patients-during-optima-trial-extension\/","title":{"rendered":"Pasatru\u2122 (garetosmab-grts) Demonstrates Zero New Heterotopic Ossification (HO) Lesions in Adult Fibrodysplasia Ossificans Progressiva (FOP) Patients During OPTIMA Trial Extension"},"content":{"rendered":"
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\n Pasatru is the first and only FDA-approved treatment demonstrating reductions in both new HO lesions and clinician-assessed flare-ups, per results of a 56-week placebo-controlled trial in adults with FOP<\/strong>\n <\/p>\n

\n Late-breaking data presented at ASBMR show sustained efficacy of Pasatru and a consistent safety profile from weeks 56 to 84, supporting long-term disease control <\/strong>\n <\/p>\n

TARRYTOWN, N.Y., Oct. 12, 2026 (GLOBE NEWSWIRE) — Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) today announced positive 84-week results from the Phase 3 OPTIMA trial evaluating Pasatru\u2122 (garetosmab-grts) in adults with fibrodysplasia ossificans progressiva (FOP). These longer-term findings for Pasatru demonstrated sustained efficacy in halting new, rogue bone growth and in significantly reducing disease flare-ups, and were presented during a late-breaking oral session at the American Society for Bone and Mineral Research (ASBMR) Annual Meeting. Pasatru was recently approved by the U.S. Food and Drug Administration (FDA) based on a 56-week, placebo-controlled trial to reduce the formation of new heterotopic ossification (HO) lesions and clinician-assessed flare-ups in adults with FOP. Pasatru is a\u00a0VelocImmune<\/em>\u00ae<\/em><\/sup>-derived, fully human monoclonal antibody that binds to and inhibits signaling by the Activin A protein, which Regeneron scientists discovered<\/a> to be a critical protein involved in the development of HO lesions in people with FOP.<\/p>\n

\u201cFOP is a devastating, relentless condition in which every flare-up can bring anxiety around potential new, abnormal bone growth and resulting loss of mobility,\u201d said Professor Richard Keen, Director of the Metabolic Bone Disease Centre, Royal National Orthopaedic Hospital, London, and global primary investigator of the OPTIMA trial. \u201cWhat patients urgently need is long-term control over new HO lesions and flare-ups to help bring peace of mind. The 84-week data from the Phase 3 OPTIMA trial demonstrate sustained disease-modifying control alongside a generally well-tolerated safety profile, which is important for the adult FOP community.\u201d<\/p>\n

OPTIMA, a global, multi-center, randomized, double-blind, placebo-controlled trial, enrolled 63 people with FOP aged 18 years and older. Trial participants were randomized to receive intravenously administered Pasatru 10 mg\/kg,\u00a0Pasatru 3 mg\/kg, or placebo once every four weeks for 56 weeks. Following this, 58 participants completed the double-blind extension phase to at least\u00a084 weeks.<\/p>\n

At 56 weeks, OPTIMA met its primary endpoint, demonstrating a 90% or greater reduction in new HO lesions, with a dramatic reduction in clinician-assessed flare-ups in adults with FOP. Detailed results on these 56-week data were recently published in The Lancet<\/em><\/a>. The endpoints were then re-assessed at 84 weeks. From week 56, there were no new HO lesions observed at week 84 for Pasatru compared to 9 new lesions for placebo as assessed by computed tomography (CT) scan. Additionally, one new HO lesion previously detected at week 56 for Pasatru 3 mg\/kg was no longer detectable at week 84. The number of new clinician-assessed flare-ups was also reduced compared to placebo, notably with 1 observed for Pasatru 10 mg\/kg, 14 for Pasatru 3 mg\/kg, and 17 for placebo.<\/p>\n

Through week 84, both doses of Pasatru had a generally well-tolerated safety profile, consistent with that observed at 56 weeks. At 56 weeks, the most common adverse reactions occurring in \u226510% of adults with FOP treated with Pasatru were abscess, acne, increased hair growth, madarosis (hair loss of eyebrows or lashes), oral ulcers, epistaxis (nosebleeds), folliculitis, paronychia (nail infection), and rash. At 84 weeks, the most common treatment-emergent adverse events were acne in participants treated with Pasatru 10 mg\/kg and epistaxis (all non-severe) in participants treated with Pasatru 3 mg\/kg. Treatment-emergent bleeding events were lower in participants treated with Pasatru 10 mg\/kg than those treated with Pasatru 3 mg\/kg or placebo. There was a dose-dependent increase in skin and soft tissue infections (33% on placebo, 53% on Pasatru 3 mg\/kg, and 78% on Pasatru 10 mg\/kg) that were all resolved with further management, with no patients discontinuing treatment as a result of infection. No deaths were reported in the trial.<\/p>\n

A Phase 3 trial of Pasatru in adolescents and children with FOP, OPTIMA 2, is planned to begin later this year. For more information, visit the Regeneron\u202fclinical trials website<\/a>, contact clinicaltrials@regeneron.com<\/a>, or call +1 844-734-6643.<\/p>\n

\n About FOP
<\/strong>FOP is an ultra-rare genetic disorder in which muscle, ligaments, and connective tissue are progressively infiltrated by rogue bone formation, a process known as HO. HO of the jaw, spine, hip, and rib cage can make basic actions such as speaking, eating, walking, or breathing difficult, leading to skeletal deformity, weight loss, and escalating loss of mobility. Worldwide, approximately 900 people are known to have been diagnosed with FOP, and most patients become wheelchair users by age 30, with the median age of survival being approximately 56.<\/p>\n

\n About the OPTIMA Clinical Trial<\/strong>\u00a0
OPTIMA is a Phase 3, multi-center, multinational trial to assess the efficacy of\u00a0Pasatru on the reduction of heterotopic bone formation and flares, as well as its safety, tolerability, and pharmacokinetics, in patients with active FOP.\u00a0<\/p>\n

The trial enrolled 63 participants\u00a0aged 18 years and older who have any FOP-causing variant of type I Activin A receptor (ACVR1),\u00a0exhibited\u00a0FOP disease activity or progression of\u00a0HO\u00a0lesions, and had a cumulative analogue joint involvement scale (CAJIS) score at screening of \u226419. CAJIS is a scoring tool used by clinicians to assess the degree of joint involvement, with higher scores\u00a0representing\u00a0a greater degree of disease severity (scale: 0 to 30). Eligible participants were randomized to receive intravenously administered Pasatru 10 mg\/kg,\u00a0Pasatru 3 mg\/kg, or placebo once every four weeks for\u00a056 weeks. Following this, participants could\u00a0then elect\u00a0to continue their originally assigned treatment in a double-blind extension phase for at least\u00a084 weeks\u00a0or\u00a0discontinue\u00a0treatment and enter an observation-only arm.<\/p>\n

During the treatment period, efficacy was evaluated through whole body CT scans for HO lesions, physician and patient assessment of flare-ups,\u00a0utilization\u00a0of CAJIS\u202fto rate joint functionality, and observances of change in disease severity.\u00a0The safety assessment includes reports of adverse events, measurement of vital signs, physical examination, and coagulation testing.\u00a0<\/p>\n

\n About Pasatru<\/strong>
\n
Regeneron has been engaged in FOP research for decades and helped to\u00a0provide\u00a0fundamental insights into\u00a0the biology and natural history of the disease.\u00a0Regeneron scientists discovered that\u202fActivin A plays a key\u00a0role in FOP<\/a>\u202fby driving HO, the\u00a0main pathology of FOP<\/a>.\u00a0Pasatru is a\u202fVelocImmune<\/em>-derived,\u00a0fully human\u00a0monoclonal antibody that binds to and inhibits signaling by the Activin A protein, which is involved in the development of heterotopic bone in people with FOP.<\/p>\n

Pasatru is FDA-approved in the U.S. to reduce formation of new HO lesions and clinician-assessed flare-ups in adults with FOP. In the European Union, a regulatory submission for Pasatru is currently under review by the European Medicines Agency. Additional regulatory submissions are planned in countries around the world, including Japan. Pasatru previously received Fast Track designation and Orphan Drug Designation from the FDA, as well as Orphan Designation by the European Medicines Agency in the European Union and the\u00a0Ministry of Health, Labour and Welfare\u00a0in Japan.<\/p>\n

Regeneron is committed to supporting people living with rare diseases. Regeneron\u2019s myRARE\u2122 program offers resources to help patients and healthcare providers, including product information, insurance benefit verification, and information about potential financial support. To learn about myRARE, visit myRARE.com<\/a> or call 1-833-4my-RARE (1-833-469-7273).<\/p>\n

\n IMPORTANT SAFETY INFORMATION<\/strong>\n <\/p>\n

\n What is the most important information I should know about PASATRU?<\/strong>\n <\/p>\n

\n PASATRU can cause serious side effects, including:<\/strong>\n <\/p>\n