Durability of Response With Selpercatinib in Patients With RET -Activated Thyroid Cancer: Long-Term Safety and Efficacy From LIBRETTO-001
Later report from the RET Fusion-Positive Solid Tumors trial registered as NCT03157128, in Journal of Clinical Oncology (2024); its title describes an updated or longer-term analysis.
Overview
Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. LIBRETTO-001 is a registrational phase I/II, single-arm, open-label study of selpercatinib in patients with RET (REarranged during Transfection)-activated cancers (ClinicalTrials.gov identifier: NCT03157128). We present long-term safety and efficacy from LIBRETTO-001 in patients with RET -mutant medullary thyroid cancer (MTC; n = 324) and RET fusion-positive thyroid cancer encompassing different histological subtypes (TC; n = 66). At the data cutoff of January 2023, the objective response rate was 82.5% among patients with cabozantinib/vandetanib-naïve MTC and 95.8% among patients with treatment-naïve TC. At a median follow-up time of 42.4 and 44.0 months in patients with cabozantinib/vandetanib-naïve and pretreated MTC, the median progression-free survival (PFS) was not reached and 41.4 months, respectively. At a median follow-up time of 24.9 and 30.4 months in patients with treatment-naïve and pretreated TC, the median PFS was not reached and 27.4 months, respectively. Three-year PFS rates were 75.2% and 87.3% among patients with cabozantinib/vandetanib-naïve MTC and treatment-naïve TC, respectively. Median PFS was similar to median duration of response for each patient group. The safety profile of selpercatinib was consistent with previous reports. With an additional follow-up of 37 months and 228 more patients from the last disclosure, selpercatinib continued to provide durable and robust responses in treatment-naïve and previously treated patients with RET -mutant MTC and RET fusion-positive TC.
Indexed on Europe PMC as PubMed record 39094065 (DOI 10.1200/jco.23.02503). Its abstract cites the registry id NCT03157128, which is how it was matched to this trial; no figure has been checked by an editor.
A second publication from the RET Fusion-Positive Solid Tumors trial, later than the first and described in its title as an update or longer-term analysis. Read it with the primary publication linked from the trial page; the record was linked automatically and its figures have not been checked by hand.
- Matched to the trial by the registry id cited in the Europe PMC record; the summary reproduces the record's abstract and no figure has been verified against the full paper.
- Chosen as a later report by words in its title (updated, long-term, final, overall survival or a year count), not by reading the paper.