Table 1_Cost-effectiveness analysis of pembrolizumab plus trastuzumab and chemotherapy as first-line treatment for HER2-positive gastric or gastroesophageal junction adenocarcinoma.docx

Based on these latest findings, this study evaluated the cost-effectiveness of pembrolizumab plus trastuzumab and chemotherapy from the perspective of the Chinese healthcare system.​</p>Design<p>Using a partitioned survival model, this study compared quality-adjusted life years (QALYs), total costs, and incremental cost-effectiveness ratios (ICERs) between pembrolizumab plus trastuzumab and chemotherapy versus trastuzumab plus chemotherapy alone.

Efficacy and safety data were derived from KEYNOTE-811, local databases, and relevant literature. To validate the robustness of the model results, sensitivity analyses were conducted. Additionally, subgroup analyses were conducted specifically for the patient population with PD-L1 expression ≥1%.​</p>Interventions<p>Pembrolizumab plus trastuzumab and chemotherapy.</p>Outcome measures<p>Total costs, life years, quality adjusted life years (QALYs), incremental QALYs and incremental cost-effectiveness ratio (ICER).</p>Results<p>In the intention-to-treat (ITT) population, pembrolizumab plus trastuzumab and chemotherapy demonstrated a gain of 0.56 QALYs compared to trastuzumab plus chemotherapy alone, with an additional cost of $322,653.47, resulting in an ICER of $571,997.42/QALY.