RET-y for more.

A small proportion (1-2%) of non-small cell lung cancers (NSCLC) have activating RET-fusions. In addition, RET-fusion(+) NSCLC often occurs mutually exclusive to other driver mutations and is associated with a high risk of brain metastases. As part of the larger LIBRETTO-001 trial, 144 patients with RET-fusion(+) NSCLC received selpercatinib. Most (73%) had received prior platinum-based chemo, and most (86%) were adenocarcinomas. In addition, 38% had a history of brain, but <10% had measurable brain mets at the time. Among those previously treated with platinum, the objective response rate was 64% with a median duration of 18 months. Among untreated patients, response rate was 85% with a median duration not reached. Among the 11 patients with measurable brain mets, 10 (91%) had an intracranial response—unsurprisingly, though, there's no mention of who received standard-of-care radiation for these. TBL: Selective RET-targeted therapy with selpercatinib shows promising activity in patients with RET-fusion(+) NSCLC. | Drilon, N Engl J Med 2020