Treatment with the kinase inhibitor lenvatinib demonstrated promising activity in patients with RET-positive non-small cell lung cancer (NSCLC), a study presented at the European Society for Medical Oncology (ESMO) 2016 Congress has shown.1
Because RET fusions activate RET kinase and occur in 1% to 2% of patients with adenocarcinoma of the lung, researchers sought to evaluate the activity and tolerability of lenvatinib in this patient population.
For the open-label, phase 2 study (ClinicalTrials.gov Identifier: NCT01877083), investigators enrolled 25 patients with RET-positive NSCLC. Of those, 13 had KIF5B-RET and 12 had other RET fusion proteins. More than half had received at least 2 prior lines of therapy, 28% had prior RET therapy, and 8% had no prior therapy.
Results showed that the overall response rate was 16%, with 14% and 17% of those receiving and not receiving prior RET therapy achieving a response, respectively. Median duration of treatment was 16 weeks.
Median progression-free survival was 7.3 months (95% CI, 3.6-10.2) and median overall survival had not yet been reached (95% CI, 5.8-not evaluable).
Researchers also found that the disease control rate and clinical benefit rate were 76% and 48%, respectively, overall. Among patients who had received prior RET therapy, the disease control rate was 86% vs 72% for patients who had not had prior RET treatment.
The most common treatment-emergent adverse events were hypertension, nausea, decreased appetite, diarrhea, proteinuria, and vomiting. In total, 92% of patients experienced grade 3 or worse treatment-emergent adverse events, with 1 patient dying due to pneumonia potentially related to lenvatinib treatment.
The findings ultimately suggest that further evaluation of lenvatinib in patients with RET-positive NSCLC is warranted.
1. Velcheti V, Hida T, Reckamp KL, et al. Phase 2 study of lenvatinib (LN) in patients (Pts) with RET fusion-positive adenocarcinoma of the lung. Poster presented at: European Society for Medical Oncology (ESMO) 2016 Congress; October 7-11, 2016; Copenhagen, Denmark.