Abstract 182P
Background
The global annual incidence of gastric cancer is about one million, with the highest incidence and mortality in East Asia. There are few Tx options for HER2+ aGC/GEJC beyond the 1st line of treatment (LOT), and Tx options differ by country/region. Hence, we sought to understand Tx patterns for HER2+ aGC/GEJC in East Asia.
Methods
HER2+ GASTA was a multinational, retrospective, chart review study. The pts with a diagnosis (Dx) of HER2+ aGC/GEJC since 01 Jan 2016 who completed 1st LOT and with at least 6 months (mo) follow-up data or died within the first 6 mo from the date of 2nd LOT initiation, were enrolled from 31 sites. The data from 01 Jan 2016 to 30 Nov 2023 was extracted. In addition to Tx patterns, real-world progression-free survival, time to treatment failure, overall survival, overall response rate, and disease control rate in each LOT were assessed.
Results
There were 356 pts included in this analysis (median age 66 years) from South Korea (n=119), Mainland China (n=137), Taiwan (n=75), and Hong Kong (n=25). At the time of Dx of aGC/GEJC, 14.6% had GEJC, 21.6% had recurrent disease, and 89.6% had metastasis, mostly seen in lymph nodes (51.4%), followed by liver (41.3%) and peritoneum (19.1%). The median number of LOTs was 3.0 (range: 2.0 to 7.0) and the transition rate from 2nd to 3rd LOT was 59.8% and from 3rd to 4th LOT was 51.6%. HER2-targeted monoclonal antibody (HER2 mAb) was used in 71.6%, 42.1%, 32.4%, and 29.1% of pts in 1st, 2nd, 3rd, and 4th LOT, respectively. The most frequently used regimen in both 1st and 2nd LOT was chemotherapy + HER2 mAb (61.0% and 23.6%, respectively), in 3rd LOT was mono chemotherapy (23.5%), and in 4th LOT was doublet chemotherapy (15.5%). The median duration of Tx in 1st, 2nd, 3rd, and 4th LOTs was 6.3 mo (range: 0.0 to 33.2), 3.6 mo (range: 0.0 to 38.9), 2.3 mo (range: 0.0 to 32.0), and 1.8 mo (range: 0.0 to 17.7), respectively.
Conclusions
This study reveals that there is no unified Tx in later LOTs in East Asia for HER2+ aGC/GEJC in the real-world setting. Although the study excluded pts who were unable to receive 2nd LOT, the results suggest that there is a high unmet need for better outcomes for HER2+ aGC/GEJC.
Clinical trial identification
NCT05606094.
Editorial acknowledgement
Medical writing support was provided by ClinChoice Private Limited.
Legal entity responsible for the study
Daiichi Sankyo Company, Limited.
Funding
This study is sponsored by Daiichi Sankyo and AstraZeneca. In March 2019, AstraZeneca entered into a global development and commercialization collaboration agreement with Daiichi Sankyo for trastuzumab deruxtecan (T-DXd; DS-8201).
Disclosure
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, Alligator Bioscience AB; Financial Interests, Institutional, Research Grant: AstraZeneca, Novartis, Array, Eli Lilly, Servier, BeiGene, MSD, Handok. W. Yeo: Financial Interests, Institutional, Invited Speaker: AstraZeneca, Daiichi Sankyo, Merck Sharpe & Dohme. Ltd, Sanofi, Taiho; Financial Interests, Institutional, Advisory Board: Bristol Meyers Squibb. J. Chen: Financial Interests, Personal, Other, Clinical trial Principle investiagator: Amgen, BMS/ONO, Janssen, MERCK, MSD, Roche, Taiho; Financial Interests, Personal, Advisory Board, expert advise meeting: Astellas, CStoone; Financial Interests, Personal, Other, Clinical trial Principal investigator speaker: AstraZeneca; Financial Interests, Personal, Invited Speaker: TTY; Financial Interests, Institutional, Other, PI for TaiRx study: TaiRx; Financial Interests, Personal, Other, Study Investigator: Daiichi Sankyo; Non-Financial Interests, Personal, Leadership Role, Presisdent: Taiwan Oncology Society. J. Lee: Financial Interests, Personal, Steering Committee Member: Seattle Genetics, AZ; Non-Financial Interests, Personal, Principal Investigator: AstraZeneca, Daichi Sankyo, Merck MSD, BMS; Non-Financial Interests, Personal, Project Lead: Samsung Bioepis, Genome and Company; Non-Financial Interests, Personal, Advisory Role: Mirati Therapeutics, Trutino Bioscience, Daichi Sankyo; Non-Financial Interests, Personal, Member: KSMO; Non-Financial Interests, Personal, Other, AP Council: ASCO. 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, Personal, Other, Durg supply for clinical trial: Merck; Financial Interests, Institutional, Coordinating PI, Drug supply for clincal trial: MSD; Financial Interests, Institutional, Local PI, drug supply for clinical trial: Zymeworks; Financial Interests, Institutional, Local PI, drug supply for clincial trial: BeiGene; Financial Interests, Personal, Local PI: roche. M. Yanagida: Financial Interests, Personal, Full or part-time Employment, Medical Affairs Excellence & Operation Group ASCA Oncology Product Department ASCA Business Division Daiichi Sankyo Co., Ltd: Daiichi Sankyo Co., Ltd; Financial Interests, Personal, Stocks/Shares: Daiichi Sankyo Co. Ltd, Otsuka Pharmaceutical Co., Ltd.; Other, Personal, Other, Employee from 2017 Apr to 2023 Jan: Taiho Pharma. R. Sato: Financial Interests, Personal, Full or part-time Employment: Daiichi Sankyo Co., Ltd. R. Xu: Financial Interests, Personal, Invited Speaker: BMS, MSD, Hutchison Pharm; Financial Interests, Personal, Advisory Board: Henrui, Beigene, Astellas, Merck, Junshi, Innovent, Keymed Biosience. All other authors have declared no conflicts of interest.