Article Text
Abstract
Introduction/Background*Pembrolizumab, an anti-PD-1 antibody, has demonstrated activity in patients with previously treated mismatch repair (MMR) deficient (dMMR; 57.1% objective response rate [ORR] as monotherapy and 63.6% ORR as combination therapy with lenvatinib) and MMR proficient (pMMR; 36.2% ORR as combination therapy with lenvatinib) endometrial cancer. ENGOT-en11/GOG-3053/KEYNOTE-B21 (NCT04634877) is a phase 3, randomized, double-blind study of pembrolizumab or placebo in combination with adjuvant chemotherapy with/without radiotherapy in patients with endometrial cancer.
Methodology Eligible patients are ≥18 years old with newly diagnosed, high-risk (stage I/II non-endometrioid or with p53 abnormality and any histology, stage III/IVA), previously untreated endometrial cancer following surgery with curative intent with no evidence of disease post-operatively. Approximately 990 patients are randomized to receive pembrolizumab 200 mg or placebo every 3 weeks (Q3W) for 6 cycles plus chemotherapy (carboplatin area under the curve [AUC] 5/6 plus paclitaxel 175 mg/m2 Q3W or carboplatin AUC 2/2.7 plus paclitaxel 60 mg/m2 QW) in stage 1. Patients receive pembrolizumab 400 mg or placebo Q6W for 6 cycles in stage 2. Radiotherapy (external beam radiotherapy [EBRT] and/or brachytherapy) ± radiosensitizing cisplatin 50 mg/m2 (days 1 and 29) may be administered after completion of chemotherapy. Randomization is stratified by MMR status (pMMR vs dMMR) and, within pMMR, by planned radiation therapy (cisplatin-EBRT vs EBRT vs no EBRT), histology (endometrioid vs non-endometrioid), and International Federation of Gynecology and Obstetrics surgical stage (I/II vs III/IVA). Dual primary endpoints are disease-free survival (DFS; per investigator assessment) and overall survival (OS). Secondary endpoints include DFS (per blinded independent central review), DFS (per investigator assessment) and OS by biomarker status (PD-L1 and tumor mutational burden), safety (per National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0), and quality of life (per European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 [EORTC QLQ-C30] and Endometrial Cancer Module [EORTC QLQ-EN24]). Enrolment began December 2020 and is ongoing at 221 sites in 28 countries.
Result(s)*N/A
Conclusion*N/A