Merck, a global science and technology leader, has announced that the US FDA has accepted its new drug application (NDA) for pimicotinib as a systemic treatment for patients with tenosynovial giant cell tumor (TGCT), a rare and debilitating joint disease.
The submission is supported by primary and long-term results from the Phase 3 MANEUVER study, which demonstrated deep and durable tumor responses and meaningful improvements in clinical outcomes.
“With pimicotinib, we have an opportunity to significantly advance care for people living with TGCT, a painful and debilitating disease that has few effective and well-tolerated treatment options beyond surgery,” said David Weinreich, Global Head of R&D and Chief Medical Officer for the Healthcare business of Merck.
“Based on clinical trial results showing not only a reduction in tumor burden, but also the ability to help alleviate symptoms like pain and stiffness in the global Phase 3 MANEUVER study, we are confident in the important role pimicotinib can play for TGCT patients in the U.S. and worldwide.”
In the study, once-daily pimicotinib showed a statistically significant improvement in objective response rate (ORR) at week 25, compared with placebo, as assessed by a blinded independent review committee.
The trial also revealed statistically significant and clinically meaningful gains in key patient-reported outcomes, including range of motion, physical function, stiffness, and pain. Longer-term follow-up, with a median of 14.3 months, confirmed that ORR continued to improve over time.
TGCT is a locally aggressive tumor that develops in or around the joints, causing swelling, stiffness, and reduced mobility, often in otherwise healthy adults. Left untreated—or in recurrent cases—the disease can lead to irreversible joint and tissue damage. Current treatment options are limited, leaving a critical need for therapies that can both shrink tumors and relieve symptoms.
Earlier, in December 2025, pimicotinib received approval from China’s National Medical Products Administration (NMPA) for adults with symptomatic TGCT where surgery could cause functional limitations or severe morbidity. Applications in other international markets are ongoing.
Merck’s FDA acceptance marks a key milestone in bringing what could become a transformative therapy to patients in the US, offering hope for improved quality of life and functional recovery.
