1422P - First-line rilvegostomig (rilve) + chemotherapy (CTx) in patients (pts) with HER2-negative (HER2–) locally advanced unresectable or metastatic gastric cancers: First report of GEMINI-Gastric sub study 2

Background

Rilve is a bispecific humanized IgG1 monoclonal antibody that blocks PD-1 and TIGIT. Gastric cancer has high expression of both receptors, suggesting potential benefit with rilve. GEMINI-Gastric (NCT05702229) is a phase 2, open-label, multicentre study. Here we report an interim analysis of Substudy 2, which tested rilve + CTx in HER2– locally advanced unresectable or metastatic gastric or gastroesophageal junction adenocarcinoma.

Methods

Pts received rilve 750 mg Q3W IV + XELOX (oxaliplatin + capecitabine) or FOLFOX (oxaliplatin + 5-FU + folinic acid). Pts were ≥18 years old, untreated for advanced cancer, with measurable disease per RECIST v1.1 and ECOG PS 0–1. Primary endpoints were ORR, analysed by baseline PD-L1 combined positive score (CPS) <5 vs ≥5, and PFS at 6 mos; safety was a secondary endpoint.

Results

At data cutoff (27 Dec 2023), 40 pts had received rilve + XELOX (n=27) or rilve + FOLFOX (n=13) and had had an opportunity for ≥3 mos follow-up (2 on-treatment scans); treatment was ongoing in 27 pts (67.5%). Median age was 63 yrs; 72.5% of pts were Asian and 52.5% had ECOG PS 0. All pts had Stage IV disease with distant metastases. Overall, unconfirmed ORR was 67.5% (81.3% and 59.1% in pts with PD-L1 CPS ≥5 and CPS

Conclusions

Rilve + CTx showed preliminary efficacy and manageable AEs. The study is ongoing and updated efficacy data will be presented.

Clinical trial identification

NCT05702229; Release date: 16 January 2023.

Editorial acknowledgement

Medical writing support, under the direction of the authors, was provided by Werner Gerber, PhD (Fourways, South Africa) of Ashfield MedComms.

Legal entity responsible for the study

AstraZeneca.

Funding

AstraZeneca.

Disclosure

F. Rivera Herrero: Financial Interests, Personal, Invited Speaker: Roche, MSD, BMS, Servier, Astellas, Amgen, Merck; Financial Interests, Personal, Advisory Board: MSD, BMS, Servier, Astellas, Amgen, AstraZeneca; Financial Interests, Institutional, Local PI: AstraZeneca, MSD, Novartis, Seagen, OBT, Inspirna. D. Oh: Financial Interests, Personal, Advisory Board: AstraZeneca, Novartis, Genentech/Roche, Merck Serono, Bayer, Taiho, Aslan, Halozyme, Zymeworks, BMS/Celgene, BeiGene, Basilea, Turning Point, Yuhan, Arcus Biosciences, IQVIA, MSD, LG Chem, Astellas, AbbVie, J-Pharma, Mirati Therapeutics, Eutilex, Moderna, Idience; Financial Interests, Institutional, Research Grant: AstraZeneca, Novartis, Array, Eli Lilly, Servier, BeiGene, MSD, Handok. K. Shitara: Financial Interests, Personal, Advisory Board: Bristol Myers Squibb, Takeda, Ono Pharmaceutical, MSD, Novartis, Daiichi Sankyo, Amgen, Guardant Health Japan Corp, Astellas Pharma Inc., Astellas, Bayer, AstraZeneca, Zymeworks Biopharmaceuticals Inc., ALX Oncology Inc.; Financial Interests, Personal, Invited Speaker: Bristol Myers Squibb, Janssen, AstraZeneca, Eli Lilly, Astellas, Ono Pharmaceutical; Financial Interests, Institutional, Research Grant: Astellas, Ono Pharmaceutical, Daiichi Sankyo, Taiho Pharmaceutical, Chugai Pharmaceutical, MSD, Eisai, Amgen, PRA Health Sciences. J. Chen: Financial Interests, Personal, Other, Clinical trial Principle investigator: Amgen, BMS/Ono, Janssen, Merck, MSD, Roche, Taiho; Financial Interests, Personal, Advisory Board, expert advise meeting: Astellas, CStoone; Financial Interests, Personal, Other, Clinical trial Principle investigator speaker: AstraZeneca; Financial Interests, Personal, Invited Speaker: TTY; Financial Interests, Institutional, Other, PI for TaiRx study: TaiRx; Non-Financial Interests, Leadership Role, President: Taiwan Oncology Society. J. Jiang: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Financial Interests, Personal, Stocks/Shares: AstraZeneca. S. Liu, Q. Zhu, X. Zhang: Financial Interests, Personal, Full or part-time Employment: AstraZeneca. Z. Dong: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Non-Financial Interests, Personal, Non financial benefits: AstraZeneca. B. Umiker: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Financial Interests, Personal, Stocks/Shares: AstraZeneca. R. Kumar: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Financial Interests, Personal, Project Lead: AstraZeneca; Financial Interests, Personal, Sponsor/Funding: AstraZeneca; Financial Interests, Personal, Stocks/Shares: AstraZeneca. S.Y. Rha: Financial Interests, Personal, Advisory Board: Indivumed, Amgen, LG biochemical, Astellas, Boehringer Ingelheim; Financial Interests, Personal, Invited Speaker: MSD, Daiichi Sankyo; Financial Interests, Personal, Steering Committee Member: Amgen; Financial Interests, Institutional, Funding: MSD, Lilly; Financial Interests, Institutional, Research Grant: BMS, Daiichi Sankyo; Financial Interests, Institutional, Local PI: Indivumed, AstraZeneca; Financial Interests, Other, Drug supply for clinical trial: Merck; Financial Interests, Institutional, Coordinating PI, Drug supply for clinical trial: MSD; Financial Interests, Institutional, Local PI, drug supply for clinical trial: Zymeworks; Financial Interests, Institutional, Local PI, drug supply for clinical trial: BeiGene; Financial Interests, Local PI: Roche. L. Shen: Financial Interests, Personal, Advisory Board: MSD, BI, Servier, AZ, Transcenta Holding Limited; Financial Interests, Institutional, Funding: BeiGene, Ltd.; Financial Interests, Institutional, Trial Chair: Rongchang Pharmaceutical, Roche, Innovent, BeiGene, Ltd., NovaRock Biotherapeutics Limited.