A Phase Ib/II Study of Lenvatinib and Pembrolizumab in Advanced Endometrial Carcinoma (Study 111/KEYNOTE-146): Long-Term Efficacy and Safety Update

Abstract

<i>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</i> JCO <i>or elsewhere, for which the primary end point has already been reported.</i>The open-label phase Ib/II Study 111/KEYNOTE-146 of daily lenvatinib 20 mg plus pembrolizumab 200 mg once every 3 weeks showed promising efficacy and tolerable safety in patients with previously treated advanced endometrial carcinoma (EC; primary data cutoff date: January 10, 2019). This updated analysis reports long-term follow-up efficacy and safety data from 108 patients with previously treated EC included in the primary analysis. End points included objective response rate, duration of response, progression-free survival, overall survival, and safety. Investigators performed tumor assessments per immune-related RECIST. At the updated data cutoff date (August 18, 2020), the median study follow-up duration was 34.7 months (95% CI, 30.9 to 41.2), the objective response rate was 39.8% (95% CI, 30.5 to 49.7), and the median duration of response was 22.9 months (95% CI, 10.2 to not estimable). The median progression-free survival and overall survival were 7.4 months (95% CI, 5.2 to 8.7) and 17.7 months (95% CI, 15.5 to 25.8), respectively. Treatment-related treatment-emergent adverse events of any grade occurred in 104 (96.3%) patients. The most common grade ≥ 3 treatment-related treatment-emergent adverse events were hypertension (33.3%), elevated lipase (9.3%), fatigue (8.3%), and diarrhea (7.4%). The results demonstrate extended efficacy and tolerability of lenvatinib plus pembrolizumab in this cohort of patients with previously treated advanced EC.