Dr. Drilon on the FDA Approval of Selpercatinib in RET Fusion+ Solid Tumors

Alexander Drilon, MD, chief, Early Drug Development Service, Memorial Sloan Kettering Cancer Center, discusses the significance of the FDA approval of selpercatinib (Retevmo) in RET fusion–positive solid tumors.

On September 21, 2022, the FDA granted accelerated approval to selpercatinib in adults with locally advanced or metastatic solid tumors harboring a RET gene fusion who have progressed on or after prior systemic therapies or who have no other satisfactory treatment options. Additionally, the FDA gave regular approval to the agent in adults with locally advanced or metastatic RET fusion–positive non–small cell lung cancer. These approvals were backed by the results of the phase 1/2 LIBRETTO-001 trial (NCT03157128), in which selpercatinib elicited a 44% response rate in all patients, including a 4.9% complete response rate and a 39% partial response rate.

This regulatory decision marks RET fusions as the fifth biomarker to be granted a tumor-agnostic indication by the FDA, Drilon says. Previously, agents targeting microsatellite instability–high disease, NTRK fusions, tumor mutational burden–high disease, and BRAFV600E–mutant disease were also approved in patients with those respective biomarkers, regardless of the type of tumor they have, Drilon notes.

Now that 1 regulatory agency has approved selpercatinib, a RET inhibitor, across solid tumors, hopefully more agencies will follow suit in approving drugs that target oncogenes or immunotherapy-predictive genomic signatures, irrespective of patients’ solid tumor type, Drilon concludes.