1586P - Characteristics, treatment (Tx) patterns and outcomes of patients with advanced/metastatic gastric cancer (GC) or gastro-esophageal junction (GEJ) adenocarcinoma previously treated with anti-HER2 therapy in an English national registry

Background

Understanding the natural history of patients with GC/GEJ adenocarcinoma treated previously with anti-HER2 regimens is useful for understanding the disease burden and selecting the optimal Tx for this population. This study reports Tx patterns and outcomes of patients with GC/GEJ adenocarcinoma treated previously with anti-HER2-based regimens.

Methods

Adults with advanced/metastatic GC/GEJ adenocarcinoma who received first-line (1L) trastuzumab-containing regimens were identified in the English Cancer Outcomes and Services Dataset (Jan 2010–Dec 2019). Tx pathways and outcomes were obtained from the Systemic Anti-Cancer Therapy Dataset, which captured nearly all treatments in England. A novel regimen-based algorithm for reporting Tx sequencing and outcomes was developed since line of therapy was not in the database. Descriptive statistics were reported. Overall survival (OS) and time to Tx discontinuation or death (TTD) underwent Kaplan–Meier analysis.

Results

A total of 948 patients were identified. At the start of their 1L trastuzumab-containing Tx, median age was 67 years (interquartile range [IQR] 57–73]); 82.1% were male; 90.4% were White; 85.4% had an ECOG status of 0–1; 26.0% had liver metastases; 1.0% had brain metastases; and 81.2% had a Charlson Comorbidity Index of 0–1. Three hundred and sixteen patients (33.3%) received 2L onward; 63 (6.6%) received 3L onward. The most common 2L regimens were paclitaxel (n=115 [36.4%]), docetaxel (n=98 [31.0%]), and 5-fluorouracil (5FU) + irinotecan (n=19 [6.0%]). Common 3L regimens included 5FU + irinotecan (n=12 [19.1%]), paclitaxel (n=11 [17.5%]) and capecitabine + irinotecan (n=10 [15.9%]). Median TTD was 2.8 months from the start of 2L. Median OS was 6.1 months (IQR, 3.4–11.2) from the start of 2L and 5.9 months (IQR, 3.2–9.5) from the start of 3L.

Conclusions

Survival of patients with GC/GEJ adenocarcinoma previously treated with 1L anti-HER2 regimens remains poor after 2L and 3L therapy, which is limited mainly to chemotherapy. These findings reflect an urgent need to improve 2L and 3L options.

Clinical trial identification

Editorial acknowledgement

Medical writing and editorial assistance were provided by Julia C. Jones (PharmD, PhD), Erica Cave (PhD), and Daria Renshaw from IQVIA, funded by the study sponsors.

Legal entity responsible for the study

AstraZeneca, Daiichi Sankyo.

Funding

AstraZeneca, Daiichi Sankyo.

Disclosure

N. Starling: Financial Interests, Personal, Advisory Board: GSK, Novartis, MSD Oncology, Servier, AstraZeneca, Pfizer, Gilead Sciences; Financial Interests, Personal, Invited Speaker: Clinical Options, Eli Lilly, Pierre Fabre, Amgen, Merck, Novartis, MSD Oncology, GSK, Servier, Seagen; Financial Interests, Institutional, Research Grant, Sept 2017 (24m) Paid to institution research: Merck; Financial Interests, Institutional, Research Grant, Nov 2017 (48m) -Paid to institution research fund: AstraZeneca; Financial Interests, Institutional, Research Grant, Jan 2018 - Paid to institution research fund: Pfizer; Financial Interests, Institutional, Research Grant, July 2018 (36m) Paid to institution research fund: BMS; Financial Interests, Institutional, Research Grant, June 2022 -: Guardant; Non-Financial Interests, Advisory Role, Ad Board uncompensated.: Guardant. L. Zhang: Financial Interests, Personal, Full or part-time Employment: Daiichi Sankyo; Non-Financial Interests, Institutional, Funding, Funding for present abstract: Daiichi Sankyo, AstraZeneca. K. Dunton, A. Struebing, Y. Xiong: Financial Interests, Personal, Full or part-time Employment: Daiichi Sankyo. C. Livings: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Non-Financial Interests, Institutional, Funding, Funding for present abstract: AstraZeneca; Financial Interests, Personal, Stocks or ownership: AstraZeneca. L. Brannman: Financial Interests, Personal, Full or part-time Employment: AstraZeneca; Non-Financial Interests, Institutional, Funding, Funding for present abstract: AstraZeneca; Financial Interests, Personal, Stocks or ownership: AstraZeneca, Biodesix, Sonic Healthcare, Medtronic. M. Yakhchi Beykloo, H. Mohamed, N. Trankov, P. Egger: Non-Financial Interests, Institutional, Funding, Funding for present abstract: IQVIA, AstraZeneca, Daiichi Sankyo; Financial Interests, Personal, Full or part-time Employment: IQVIA.