FDA Approves First Treatment for Tenosynovial Giant Cell Tumor

The Food and Drug Administration has approved Turalio (pexidartinib; Daiichi Sankyo) for the treatment of adult patients with symptomatic tenosynovial giant cell tumor (TGCT) associated with severe morbidity or functional limitations and not amenable to improvement with surgery.

Turalio is an orally administered kinase inhibitor that targets colony stimulating factor-1 receptor (CSF1R); overexpression of the CSF1R ligand promotes cell proliferation and accumulation in the synovium.

The approval was based on data from the pivotal phase 3 ENLIVEN study (N=120) which showed an overall response rate (ORR; primary end point) of 38% in the Turalio arm (complete response: 15%; partial response: 23%) vs 0% for placebo (P<.0001); ORR by tumor volume score was 56% in patients randomized to the Turalio arm and 0% in patients randomized to the placebo arm (P< .0001). In addition, patients treated with Turalio showed a statistically significant improvement in the mean change from baseline in range of motion of the affected joint at Week 25 compared with placebo.

With regard to safety, the most common adverse reactions were increased lactate dehydrogenase, increased AST/ALT, hair color changes, fatigue, decreased neutrophils, increased cholesterol, increased alkaline phosphatase, decreased lymphocytes, eye edema, decreased hemoglobin, rash, dysgeusia, and decreased phosphate.

Example of an objective response to treatment with Turalio (pexidartinib). At baseline (top photo), the patient was unable to straighten the knee and experienced such debilitating symptoms that amputation was considered. The bottom photos show tumor reduction after 4 months of treatment with Turalio. Each patient’s results will vary. The need to consider future surgery for TGCT, including amputation, may be warranted. From The New England Journal of Medicine, Tap W, et al. Structure-Guided Blockade of CSF1R Kinase in Tenosynovial Giant-Cell Tumor, Volume 373, Pages 428-437.
Copyright © 2015 Massachusetts Medical Society. Reprinted with permission from Massachusetts Medical Society.

Due to the risk of serious and potentially fatal liver injury, Turalio is available only through a restricted program called the Turalio REMS. Under the REMS, only certified pharmacies and healthcare settings can dispense Turalio. Patients must be enrolled in the program prior to administration in a medically supervised setting.  

“The FDA approval of Turalio represents a paradigm shift in the treatment of carefully selected TGCT patients who face significant disease morbidity and for whom surgery is not an option,” said William D. Tap, MD, Chief of the Sarcoma Medical Oncology Service at Memorial Sloan Kettering Cancer Center, New York, and lead investigator for the pivotal phase 3 ENLIVEN study. “We now have a new oral treatment option that can have a meaningful clinical benefit in select patients, including a reduction in tumor size.”

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Turalio will be available as 200mg capsules in 28-count and 120-count bottles.

For more information visit turalio.com.