Merck KGaA and Abbisko Therapeutics have announced positive topline results from the phase 3 MANEUVER trial evaluating pimicotinib in patients with tenosynovial giant cell tumors (TGCTs). The study, which included patients eligible for systemic therapy who had not previously received anti-CSF-1/CSF-1R therapy, met its primary endpoint with clinically meaningful improvements in secondary endpoints.
The MANEUVER trial demonstrated a significant objective response rate (ORR) of 54% for pimicotinib compared to 3.2% for placebo at week 25. The study also showed statistically significant and clinically meaningful improvements in secondary endpoints associated with patient outcomes in TGCT, including stiffness and pain. The companies reported that pimicotinib was well-tolerated, with a safety profile consistent with previously reported data.
About Tenosynovial Giant Cell Tumors (TGCTs)
TGCT is a rare, benign, and locally aggressive tumor that originates in the synovial lining of joints, bursae, and tendon sheaths. Patients with TGCT often experience joint pain, stiffness, swelling, and a reduced range of motion. If left untreated or in recurrent cases, the disease can cause irreversible damage to bones, joints, and surrounding tissues.
Pimicotinib: A CSF-1R Inhibitor
Pimicotinib, developed by Abbisko, is an orally administered, highly selective, and potent small-molecule inhibitor of CSF-1R. It has been granted breakthrough therapy designation in the US and China, as well as priority medicine designation in the EU for TGCT.
In December of last year, Merck and Abbisko entered into an agreement granting Merck an exclusive license to commercialize pimicotinib in mainland China, Hong Kong, Macau, and Taiwan, with an option for the rest of the world.
Expert Commentary
Danny Bar-Zohar, global head of research and development and chief medical officer for the healthcare business sector of Merck, stated, "This phase 3 data from MANEUVER confirms results of Abbisko’s phase 1 study, indicating that targeting CSF-1R with pimicotinib has the potential to offer a new treatment option for patients. As we work with Abbisko to review the data from this study and prepare to share it with regulators in China, we are focused on our shared goal of bringing pimicotinib to patients in need."
