Positive Data from Phase 3 Trial for Potential TGCT Treatment

According to a story from BioSpace, the drug developer Daiichi Sankyo Company Limited has recently announced positive data resulting from a pooled anaylsis of a phase 3 trial and a phase 1 extension study. This data is in regards to the company’s experimental drug pexidartinib. The drug was being tested in these trials as a treatment for tenosynovial giant cell tumor (TGCT), also known as pigmented villonodular synovitis. These findings were first presented at the annual meeting of the American Society of Clinical Oncology on June 1st.

About Tenosynovial Giant Cell Tumor (TGCT)

Tenosynovial giant cell tumor (TGCT) is a disease which affects the joints, most typically the hip or knee. The illness is characterized by overgrowth of the joint lining and inflammation. Unfortunately the cause of this disease remains a mystery; prevailing theories include abnormal metabolism of fat, blood within the affected joint, or repeated inflammation. A risk factor is prior trauma affecting the joint where the disease appears. The symptoms of TGCT include sudden swelling and joint pain, loss of range of motion, progressive swelling and pain, bone erosion, and damage to surrounding tissues. The disease has the potential to spread from the affected joint and can lead to permanent disability and chronic pain. Treatment generally includes the surgical removal of the joint lining, radiation therapy, or replacement of the affected joint. TGCT can easily recur. To learn more about this disease, click here.

Data Findings

The data demonstrated that treatment with pexidartinib at a median duration of 17 months was able to obtain 54 percent overall response based on specifications from the Response Evaluation Criteria in Solid Tumors (RECIST). A 64 percent overall response was achieved based on Tumor Volume Score. Safety data was largely consistent with other studies of the drug; adverse events were mostly minor, although in other studies pexidartinib has been associated with liver toxicity.

The results suggest that pexidartinib could be a valuable therapeutic option for patients affected by TGCT, particularly if they are not eligible for joint replacement surgery. The experimental drug has earned Orphan Drug designation, Breakthrough Therapy designation, and Priority Review from the US Food and Drug Administration (FDA).