Abstract 158P
Background
HER2-positive advanced gastric cancer patients have a poor prognosis. Current first-line treatment is Trastuzumab combined with chemotherapy. Inetetamab, a new anti-HER2 drug, has not been evaluated for its efficacy and safety in gastric cancer. This study aims to assess the effectiveness and safety of the SOX regimen combined with Inetetamab as a first-line treatment for HER2-positive advanced gastric cancer.
Methods
Eligible patients with HER2-positive advanced gastric cancer or gastroesophageal junction adenocarcinoma were randomized into two treatment arms: one arm received inetetamab in combination with the SOX regimen, while the other arm received trastuzumab combined with the SOX regimen. Following completion of 4 to 6 cycles of treatment, patients exhibiting stable disease were administered maintenance therapy. The primary objectives of this study were to evaluate progression-free survival (PFS) and overall survival (OS), while secondary endpoints encompassed the assessment of objective response rate (ORR), disease control rate (DCR), and the occurrence of adverse events (AEs).
Results
A total of 38 patients enrolled, with 37 completing (18 inetetamab, 19 trastuzumab). Median PFS was significantly longer with inetetamab (8.5 months) vs trastuzumab (7.3 months, P=0.046). Median OS (15.3 vs 14.3 months), ORR (50% vs 42%), and DCR (88.9% vs 94.7%) showed no significant differences. Common AEs included hematological toxicities and gastrointestinal symptoms. Grade ≥ 3 AEs occurred in 56% of inetetamab patients and 47% of trastuzumab patients (P=0.63).
Conclusions
In the first-line therapeutic setting for patients with HER2-positive advanced gastric cancer, inetetamab demonstrated comparable efficacy to trastuzumab, with a notable advantage in median progression-free survival (PFS) favoring the inetetamab group. Both treatment arms exhibited favorable safety profiles.
Clinical trial identification
ChiCTR2100051574.
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.