Lenvatinib plus pembrolizumab for patients with previously treated, advanced, triple-negative breast cancer: Results from the triple-negative breast cancer cohort of the phase 2 LEAP-005 Study

Abstract

Background: Novel treatments are needed for patients with advanced, triple-negative breast cancer (TNBC) that progresses or recurs after first-line treatment with chemotherapy. The authors report results from the TNBC cohort of the multicohort, open-label, single-arm, phase 2 LEAP-005 study of lenvatinib plus pembrolizumab in patients with advanced solid tumors (ClinicalTrials.gov identifier NCT03797326). Methods: Eligible patients had metastatic or unresectable TNBC with disease progression after one or two lines of therapy. Patients received lenvatinib (20 mg daily) plus pembrolizumab (200 mg every 3 weeks; up to 35 cycles). The primary end points were the objective response rate according to Response Evaluation Criteria in Solid Tumors, version 1.1, and safety (adverse events graded by the National Cancer Institute&apos;s Common Terminology Criteria for Adverse Events, version 4.0). Duration of response, progression-free survival, and overall survival were secondary end points. Results: Thirty-one patients were enrolled. The objective response rate by investigator assessment was 23% (95% confidence interval [CI], 10%-41%). Overall, the objective response rate by blinded independent central review (BICR) was 32% (95% CI, 17%-51%); and, in patients who had programmed cell death ligand 1 combined positive scores >= 10 (n = 8) and <10 (n = 22), the objective response rate was 50% (95% CI, 16%-84%) and 27% (95% CI, 11%-50%), respectively. The median duration of response by BICR was 12.1 months (range, from 3.0+ to 37.9+ months). The median progression-free survival by BICR was 5.1 months (95% CI, 1.9-11.8 months) and the median overall survival was 11.4 months (95% CI, 4.1-21.7 months). Treatment-related adverse events occurred in 94% of patients (grade 3, 52%; grade 4, 0%). One patient died due to a treatment-related adverse event of subarachnoid hemorrhage. Conclusions: The combination of lenvatinib plus pembrolizumab demonstrated antitumor activity with a manageable safety profile in patients with previously treated, advanced TNBC.