Abbisko Therapeutics Co Ltd (HKEX code: 02256.HK), a China-based biopharmaceutical company, announced on Tuesday that the US Food and Drug Administration (FDA) has approved PIMJETMI (pimicotinib), a small-molecule colony-stimulating factor 1 receptor (CSF-1R) inhibitor, as a systemic treatment for adults with symptomatic tenosynovial giant cell tumour (TGCT), for which surgical resection may cause worsening functional limitation or severe morbidity.

According to Abbisko, PIMJETMI is an orally available and potent small-molecule CSF-1R inhibitor independently developed by Abbisko Therapeutics, with global commercialisation rights granted to Merck KGaA, Darmstadt, Germany.

The US FDA approval marks the fourth NDA approval for PIMJETMI, following approvals in China by the National Medical Products Administration (NMPA) in December 2025, in Canada by Health Canada in June 2026, and in Switzerland by the Swiss Agency for Therapeutic Products (Swissmedic) in October 2026, further accelerating the global commercialisation plan. Upon the first commercial sale in the US, Abbisko will receive an additional milestone payment.

Abbisko is also eligible to receive double-digit royalties on global net sales of PIMJETMI, as well as potential payments relating to other regulatory, development, and commercial sales milestones.

FDA approval of PIMJETMI is based on primary and longer-term results from the global Phase III MANEUVER study and the Open-Label Extension.

The applications for PIMJETMI in the US, Canada and Switzerland were reviewed under Project Orbis, an international collaboration framework initiated by the FDA Oncology Center of Excellence to facilitate collaboration among participating regulatory authorities and accelerate the review of oncology products.