On May 8, 2020, the FDA accelerated the approval of Retevmo (selpercatinib; from Lilly Oncology), an oral kinase inhibitor, for the treatment of metastatic non–small-cell lung cancer (NSCLC), as well as for patients with several types of metastatic thyroid cancer that are associated with RET fusions or mutations, as determined by an FDA-approved test. Retevmo is the first drug to be approved specifically for patients with cancer that is linked to RET mutations or fusions.
“The FDA is committed to reviewing treatments like Retevmo that are targeted to specific subsets of patients with cancer,” said Richard Pazdur, MD, Director of the FDA’s Oncology Center of Excellence.
The approval of Retevmo was based on the results of a clinical trial of patients who had 1 of 3 types of tumors associated with RET fusions or mutations, including patients with metastatic NSCLC and RET fusions or mutations and patients with 2 different types of metastatic thyroid cancer.
The study included 105 adults with NSCLC and RET fusion who had previously received chemotherapy. Overall, 64% of the patients responded to treatment with Retevmo, and the responses lasted 6 or more months in the majority (81%) of the patients. Similar results were seen in the 39 patients with NSCLC and RET fusion who had not received any previous therapy for lung cancer. The study also included patients with metastatic thyroid cancer, who showed similar positive responses to Retevmo.
The most common side effects with Retevmo were increased laboratory test results, including AST, ALT, and blood glucose levels; decreased white blood cell count, albumin, and calcium levels; dry mouth; diarrhea; increased creatinine, alkaline phosphatase, and hypertension; fatigue; swelling in the body or limbs; low platelet count; increased cholesterol; rash; constipation; and decreased sodium levels.
The serious side effects with Retevmo include liver side effects, elevated blood pressure, abnormal heartbeat, bleeding, and allergic reactions. Retevmo should be stopped temporarily or permanently in patients with liver side effects.