177O - Lenvatinib plus pembrolizumab versus treatment of physician’s choice in patients with previously treated advanced endometrial cancer: Study 309/KEYNOTE-775 Asian subgroup

Background

In the global phase 3 Study 309/KEYNOTE-775 (NCT03517449), lenvatinib (len) + pembrolizumab (pembro) significantly improved PFS and OS vs treatment of physician’s choice chemotherapy (TPC) in patients (pts) with previously treated advanced endometrial cancer (EC). We present outcomes for the Asian subgroup from Study 309/KEYNOTE-775 at the time of final prespecified efficacy analysis.

Methods

Eligible pts were women ≥18 y with histologically confirmed advanced, recurrent, or metastatic EC with PD after 1 prior platinum-based chemo regimen (2 if 1 given in neoadjuvant or adjuvant setting) and ECOG PS 0-1. Pts were randomized 1:1 to len 20 mg PO QD + pembro 200 mg IV Q3W (up to 35 cycles) or TPC (doxorubicin 60 mg/m2 IV Q3W or paclitaxel 80 mg/m2 IV QW [3 wks on/1 wk off]). Randomization was first stratified by MMR status (pMMR or dMMR), then pts with pMMR disease were further stratified by ECOG PS, geographic region, and history of pelvic radiation. Primary endpoints were PFS per RECIST v1.1 by BICR and OS. All analyses are descriptive.

Results

155 pts from the East Asian countries of Japan, Taiwan, and South Korea were enrolled (len + pembro, n = 77; TPC, n = 78); 134 pts had pMMR disease (len + pembro, n = 66; TPC, n = 68). Median time from randomization to data cutoff (Mar 1, 2022) was 34.3 (range, 25.1−43.0) mo. Efficacy results for pts with pMMR disease and all-comer pts are shown in the table. In all-comer pts, grade 3–5 treatment-related AEs occurred in 74.0% and 72.0% of pts in the len + pembro and TPC groups, respectively. Any subsequent anticancer treatment was received by 41.6% vs 48.7% of all-comer pts, respectively; 3.9% vs 15.4% received any subsequent PD-(L)1 inhibitor. Table: 177O

Efficacy results in Asian subgroup

Conclusions

Consistent with the global study population, len + pembro provided clinically meaningful improvement in PFS, OS, and ORR vs TPC with manageable safety in Asian women with previously treated advanced EC.

Clinical trial identification

NCT03517449.

Editorial acknowledgement

Medical writing and editorial assistance was provided by Christabel Wilson, MSc, of ICON plc (Blue Bell, PA, USA). This assistance was funded by Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

Legal entity responsible for the study

Eisai Inc., Nutley, NJ, USA, and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

Funding

Eisai Inc., Nutley, NJ, USA, and Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA.

Disclosure

K. Yonemori: Financial Interests, Personal, Other, Lecture Fees: Eisai, Pfizer, Eli Lilly, Takeda, Chugai, MSD, Fuji Film Pharma, Bayer, Boeringer Ingelheim, Daiichi-Sankyo, AstraZeneca; Financial Interests, Personal, Advisory Board: Novarits, Eisai, Chugai, AstraZeneca, Takeda, Genmab, Sanofi, OncXerna; Financial Interests, Personal, Research Grant: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, Daiichi-Sankyo, AstraZeneca, Taiho, Pfizer, Novartis, Takeda, Chugai, Ono, Seattle Genetics, Eisai, Eli Lilly, Genmab, Boehringer Ingelheim, Kyowa Hakko Kirin, Nihon Kayaku, Haihe. K. Fujiwara: Financial Interests, Personal, Research Grant: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, and Eisai. K. Hasegawa: Financial Interests, Personal, Other, lecture fees, honoraria, or other fees: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA. K. Ushijima, S. Minobe: Financial Interests, Personal, Research Grant: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA. J. Kim: Financial Interests, Personal, Advisory Role: Takeda Korea, GSK Korea, Boryung, Vifor Pharma, CMIC, MSD Korea, AstraZeneca, Janssen, and LG Pharma. K. Yamamoto, S. Han: Financial Interests, Personal, Full or part-time Employment: MSD K.K., Tokyo, Japan. J. McKenzie: Financial Interests, Personal, Full or part-time Employment: Eisai Inc., Nutley, NJ, USA. G. Barresi: Financial Interests, Personal, Full or part-time Employment: Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA. T. Miura: Financial Interests, Personal, Full or part-time Employment: Eisai Co., Ltd., Tokyo, Japan. V. Makker: Financial Interests, Institutional, Funding: AstraZeneca, Clovis, Eisai, Karyopharm, Mereo, Merck Sharp & Dohme LLC, a subsidiary of Merck & Co., Inc., Rahway, NJ, USA, Takeda, and Zymeworks. Y.M. Kim: Financial Interests, Personal, Research Grant: MSD, AstraZeneca, Roche, Clovis Oncology, Janssen, ImmunoGen, Regeneron, Zentalis, BeiGene. All other authors have declared no conflicts of interest.