OBJECTIVES: To describe patient characteristics, treatment patterns, and outcomes for patients with rearranged during transfection (RET) fusion-positive NSCLC treated with selpercatinib from the interim data cut of the SPRINT-RET study.

METHODS: SPRINT-RET is a European multi-country, observational, retrospective study of selpercatinib-treated patients with advanced RET fusion-positive NSCLC, RET fusion-positive thyroid cancer, or RET mutation-positive medullary thyroid cancer in real-world clinical practice. This interim analysis included patients with RET fusion-positive NSCLC across Austria, Germany, Netherlands, Spain, and UK. Demographic and clinical characteristics data presented here were collected between Apr23-Mar24 and analysed descriptively. Kaplan Meier method was used to describe time to-event-outcomes.

RESULTS: This analysis included 29 RET fusion-positive NSCLC patients. The mean (±SD) age was 66.9 (±11.6) years, 62.1% were females and 52.2% were never-smokers. The majority (71.4%) of patients were initially diagnosed with disease stage IIIb-IV, most (96.6%) were adenocarcinomas. Selpercatinib was initiated in 1^st line, 2^nd line, and ≥3^rd line for 10 (34.5%), 13 (44.8%), and 6 (20.7%) patients respectively. Selpercatinib was initiated as monotherapy in 96.6% of patients. At a median follow-up of 13.5 months (95% confidence interval [CI]:5.7,24.2), the real-world (rw) overall response rate (ORR) was 79.3% (95% CI:60.3,92.0), and the rw disease control rate was 89.7% (95% CI:72.6,97.8). The median rw progression free survival (PFS) was 25.0 months (95% CI:10.3, not reached). The 12-month overall survival rate was 89.8% (95% CI:64.8,97.4). At a median follow-up of 13.5 months (95%CI: 5.7,24.2), 23 (79.3%) patients were alive and 20 (69.0%) were still on treatment.

CONCLUSIONS: The rwORR and median rwPFS demonstrated strong rw effectiveness of selpercatinib, comparable to Phase 3 LIBRETTO-431 trial interim analysis and long-term follow-up of the Phase 1/2 LIBRETTO-001 trial. Final analysis will assess efficacy outcomes with longer follow-up especially for patients treated in the first line setting.