Pembrolizumab with or Without Lenvatinib as First-line Therapy for Patients with Advanced Urothelial Carcinoma (LEAP-011): A Phase 3, Randomized, Double-Blind Trial

Background: Pembrolizumab plus lenvatinib has shown antitumor activity and acceptable safety in patients with platinum-refractory urothelial carcinoma (UC). Objective: To evaluate pembrolizumab plus either lenvatinib or placebo as first-line therapy for advanced UC in the phase 3 LEAP-011 study. Design, setting, and participants: Patients with advanced UC who were ineligible for cisplatin-based therapy or any platinum-based chemotherapy were enrolled. Intervention: Patients were randomly assigned (1:1) to pembrolizumab 200 mg intravenously every 3 wk plus either lenvatinib 20 mg or placebo orally once daily. Outcome measurements and statistical analysis: Dual primary endpoints were progression-free survival (PFS) and overall survival (OS). An external data monitoring committee (DMC) regularly reviewed safety and efficacy data every 3 mo. Results and limitations: Between June 25, 2019 and July 21, 2021, 487 patients were allocated to receive lenvatinib plus pembrolizumab (n = 245) or placebo plus pembrolizumab (n = 242). The median time from randomization to the data cutoff date (July 26, 2021) was 12.8 mo (interquartile range, 6.9–19.3). The median PFS was 4.5 mo in the combination arm and 4.0 mo in the pembrolizumab arm (hazard ratio [HR] 0.90 [95% confidence interval {CI} 0.72–1.14]). The median OS was 11.8 mo for the combination arm and 12.9 mo for the pembrolizumab arm (HR 1.14 [95% CI 0.87–1.48]). Grade 3–5 adverse events attributed to trial treatment occurred in 123 of 241 patients (51%) treated with lenvatinib plus pembrolizumab and in 66 of 242 patients (27%) treated with placebo plus pembrolizumab. This trial was terminated earlier than initially planned based on recommendation from the DMC. Conclusions: The benefit-to-risk ratio for first-line lenvatinib plus pembrolizumab was not considered favorable versus pembrolizumab plus placebo as first-line therapy in patients with advanced UC. Patient summary: Lenvatinib plus pembrolizumab was not more effective than pembrolizumab plus placebo in patients with advanced urothelial carcinoma.