Pimicotinib versus placebo in tenosynovial giant cell tumor (TGCT): a plain language summary of the MANEUVER clinical trial

Plain Language SummaryWhat is this summary about?This summary describes the main findings of the MANEUVER clinical trial for pimicotinib, a once-daily treatment. The goal was to see if pimicotinib could significantly reduce tumor size after 24 weeks of treatment in clinical trial participants with tenosynovial giant cell tumor (TGCT) compared with placebo (a dummy treatment).TGCT is a rare tumor that leads to pain, stiffness, and difficulty moving. This makes daily activities challenging. It is usually treated with surgery, but surgery may not be suitable in all cases and can cause serious complications.In the clinical trial, researchers looked at whether pimicotinib treatment significantly reduced tumor size, how far participants could move the affected joint (range of motion), and what treatment side effects occurred. Participants reported their symptoms (such as stiffness and pain), their physical function, and how they felt about their overall health and well-being (quality of life).What are the key takeaways? Fifty-four percent of participants who took pimicotinib (34 of 63 participants) had significant tumor shrinkage over 24 weeks, as defined by a 30% or greater reduction in tumor size based on tumor length. In comparison, 3% of participants who received placebo (1 of 31 participants) had significant tumor shrinkage over the same period.Participants treated with pimicotinib had improved range of motion of the affected joint. They also reported reduced stiffness and pain, and improved physical function. These improvements were observed early in the clinical trial and continued over time to week 25, regardless of the amount of tumor shrinkage at week 25.Most side effects in participants treated with pimicotinib were considered mild, manageable, and reversible, and there were no serious liver damage or skin or hair color changes up to week 25.What were the main conclusions reported by the researchers?Pimicotinib effectively shrank TGCT and had manageable side effects. This clinical trial showed that pimicotinib may be a helpful treatment option for people with TGCT that cannot be completely removed surgically, or for whom surgery could cause serious complications or substantial loss of function.Clinical trial number: NCT05804045