FDA approves Pimjetmi for tenosynovial giant cell tumor

The FDA has approved pimicotinib, sold as Pimjetmi, for adults with symptomatic tenosynovial giant cell tumor where surgery could worsen function, after the drug produced a 56 percent response rate against 3 percent on placebo at week 25.

Why it matters: The approval gives Abbisko its first commercial medicine and hands Merck KGaA, Darmstadt, Germany a new rare tumor product in the United States, with a milestone payment and double-digit royalties flowing back to the Chinese developer.

Data as of Company announcement of November 11, 2026, read in full in this run; the approval is an FDA action reported by the sponsor, and the efficacy figures are the Phase 3 MANEUVER results stated in the release. The FDA's own approval notice was not among the candidates read in this run.

The Food and Drug Administration has approved PIMJETMI (pimicotinib) as a systemic treatment for adults with symptomatic tenosynovial giant cell tumor, or TGCT, for which surgical resection may cause worsening functional limitation or severe morbidity, Abbisko Therapeutics announced on November 11. The drug is an oral small-molecule inhibitor of the colony-stimulating factor 1 receptor, developed by the Shanghai-based, Hong Kong-listed Abbisko and licensed for global commercialisation to Merck KGaA, Darmstadt, Germany.

The approval rests on the global Phase 3 MANEUVER study and its open-label extension. At week 25, the objective response rate assessed by blinded independent review was 56 percent on pimicotinib against 3 percent on placebo, a difference the company reported at p less than 0.0001. The drug also improved relative range of motion, physical functioning and pain against placebo. In longer-term follow-up, with a median of 14.3 months for patients first randomised to pimicotinib, the median duration of response had not been reached, and 77 percent of patients who had responded at week 25 maintained clinical benefit after a further 12 months.

The United States is the fourth market to clear the drug, after China in December 2025, Canada in June 2026 and Switzerland in October 2026, and the United States, Canadian and Swiss applications were reviewed under Project Orbis, the FDA Oncology Center of Excellence framework for parallel international review. Under the December 2023 licensing agreement, Merck KGaA is responsible for commercialisation worldwide. Abbisko receives a further milestone payment on the first commercial sale in the United States and is eligible for double-digit royalties on global net sales, plus other regulatory, development and sales milestone payments. The amounts were not disclosed.

TGCT is a rare, locally aggressive tumor of the joints, tendon sheaths and bursae, driven by overexpression of colony-stimulating factor 1, which causes pain, swelling, stiffness and loss of mobility. For Abbisko, founded in 2016, Pimjetmi is its first proprietary medicine to reach the market, and the approval is the clearest test yet of its model of developing in China and licensing global commercialisation to a Western partner.

FDA approves Pimjetmi for tenosynovial giant cell tumor

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