FDA Approves Selpercatinib for RET Fusion–Positive NSCLC
Posted: Monday, May 11, 2020
On May 8, the U.S. Food and Drug Administration (FDA) approved the use of the RET inhibitor selpercatinib (Retevmo) to treat adult patients with metastatic non–small cell lung cancer (NSCLC) whose tumors have a mutation in the RET gene. Before patients begin treatment, the identification of a RET gene alteration must be determined using laboratory testing.
The FDA approval is based on the results of the LIBRETTO-001 phase I/II trial, which assessed the overall response rate and duration of response in patients administered selpercatinib. The study enrolled 105 patients with RET fusion–positive NSCLC who were previously treated with platinum chemotherapy as well as 39 patients with RET fusion–positive NSCLC who were naive to treatment. During the clinical trial, patients received a 160-mg oral dose of selpercatinib twice daily until disease progression or unacceptable toxicity.
The overall response rate was 64% in patients who were previously treated with platinum chemotherapy. Of the 105 patients, 81% had a treatment response that lasted for at least 6 months. Patients who had never undergone treatment had an overall response rate of 84%. Of these 39 patients, 58% had a response to treatment that lasted for at least 6 months.
Common side effects experienced in patients administered selpercatinib included increased levels of aspartate aminotransferase and alanine aminotransferase enzymes in the liver, increased blood sugar, decreased white blood cell count, decreased albumin in the blood, decreased calcium in the blood, dry mouth, diarrhea, increased creatinine, increased levels of alkaline phosphatase, hypertension, fatigue, swelling in the body or limbs, low platelet count, increased cholesterol, rash, constipation, and decreased sodium in the blood. Serious side effects of selpercatinib included hepatotoxicity, elevated blood pressure, QT prolongation, bleeding, and allergic reactions.