Epithelioid sarcoma is a rare form (accounts for <1%) of soft tissue sarcoma. Until now, there have been no treatments specifically for this patient population. But the FDA has just announced accelerated approval for a drug called Tazverik. This therapy will be available to patients who are at least 16 years of age who have metastatic or locally advanced disease which is not able to be surgically treated. This approval was unanimous, with all members of the committee claiming that the benefits of this treatment outweigh any of the potential risks.
Tazverik works by blocking EZH2 methyltransferase activity and therefore stopping cancer cells from continuing to grow. Until this therapy, this patient population was relying on general cancer treatments such as surgery and chemotherapy. But with nothing specialized to their needs, the outlook was still grim. Even with treatment, the likelihood that the cancer would spread regionally was high. Not only that, but at the time that patients with epithelioid sarcoma are diagnosed, 50% already have metastatic disease which is life-threatening.
Tazverik does have risks of side effects, and you should read the full information on the therapy and consult with your healthcare team before making any treatment decisions. However the most common AEs were fatigue, constipation, vomiting, nausea, pain, and a decrease in appetite.
The approval was given based on evidence from a clinical trial which examined the effect of 800 mg of the drug taken twice a day in 62 patients. Treatment was continued until either the participant reached a level of toxicity that was too high or the disease progressed. Every 8 weeks the tumor was assessed to document its size. Researchers documented the partial or complete shrinkage of the cancerous cells.
Overall, the response rate was 15%. Of these, 1.6% of the patients had complete response. For 6 of the 9 patients who had a documented response, the response was sustained for at least 6 months.
You can read more about this new treatment option for epithelioid sarcoma here.