Early-Phase Trial Update on Use of Selpercatinib in RET Fusion–Positive NSCLC

By: Justine Landin, PhD
Posted: Friday, December 2, 2022

The highly selective RET kinase inhibitor selpercatinib may improve clinical outcomes for some patients with RET fusion–positive non–small cell lung cancer (NSCLC), according to research conducted by Alexander Drilon, MD, of Memorial Sloan Kettering Cancer Center, New York, and colleagues. In fact, many patients with NSCLC who received selpercatinib achieved a good overall response rate, despite being either treatment-naive or having received prior platinum-based chemotherapy. The updated findings of the phase I/II, single-arm, open-label LIBRETTO-001 were published in the Journal of Clinical Oncology.

“In a large cohort with extended follow-up, selpercatinib continued to demonstrate durable and robust responses, including intracranial activity, in previously treated and treatment-naive patients with RET fusion–positive NSCLC,” stated the study investigators.

Patients with RET fusion–positive NSCLC who had either received previous platinum-based chemotherapy (n = 247) or had received no treatment (n = 69) were enrolled. Patients in phase I were administered selpercatinib at 20 mg once a day or 20 to 240 mg twice a day. Patients in phase II received 160 mg of selpercatinib twice a day. Radiologic tumor assessments were obtained at baseline, then every 8 weeks for 1 year, and subsequently every 12 weeks. Brain imaging was obtained to investigate intracranial responses.

Treatment-naive patients had an overall response rate of 84%, with 6% achieving a complete response. The median duration of response was 20.2 months, and the median progression-free survival was 22.0 months. For patients who had previously received platinum-based chemotherapy, the overall response rate was 61%, and 7% of patients achieved a complete response. The median duration of response was 28.6 months, and the median progression-free survival was 24.9 months. Patients who had exhibited brain metastases at baseline had an intracranial overall response rate of 85%, 27% of which were complete responses.

Disclosure: For full disclosures of the study authors, visit ascopubs.org.

Journal of Clinical Oncology

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