Cost-effectiveness analysis of ramucirumab plus paclitaxel as switch maintenance versus continuation of first-line oxaliplatin-based chemotherapy for advanced HER2-negative gastric or gastro-esophageal junction cancer.

Background: Ramucirumab in combination with paclitaxel has demonstrated substantial antitumor activity in the treatment of advanced human epidermal growth factor receptor-2 (HER2)-negative gastric cancer (GC) or gastro-esophageal junction cancer (GEJC). However, the cost-effectiveness of this regimen in this patient population remains uncertain, particularly within the Chinese healthcare context. Objective: This study aimed to assess the cost-effectiveness of ramucirumab plus paclitaxel as a switch maintenance regimen compared to continuing first-line chemotherapy for patients with advanced HER2-negative GC or GEJC, from the perspective of the Chinese healthcare system. Design: A health economic evaluation was conducted to compare two treatment strategies. Methods: A partitioned survival model was developed to project the disease progression of HER2-negative GC or GEJC. Data for overall survival and progression-free survival were extracted from the ARMANI trial and were extrapolated to project long-term survival outcomes. Direct medical costs and utility values were gathered. The main outcome measures, including the cost, utility, and incremental cost-utility ratio (ICUR), were used to determine the cost-effectiveness of the ramucirumab plus paclitaxel as switch maintenance regimen. Sensitivity analyses, including one-way sensitivity analysis (OWSA) and probabilistic sensitivity analysis (PSA), were performed to evaluate the robustness of the findings. Results: The base-case analysis revealed that the ICUR for ramucirumab plus paclitaxel as a switch maintenance regimen was ¥1,097,535 per quality-adjusted life-year (QALY) compared to the continuation of first-line chemotherapy. OWSA showed that the ICUR was sensitive to variations in the cost of ramucirumab, patient weight, and the cost of subsequent treatments in the continuation of first-line chemotherapy group. Results from the PSA indicated that the switch maintenance regimen had a very low probability of cost-effectiveness, at just 0.4%. In contrast, the continuation of the first-line regimen demonstrated a high likelihood of being cost-effective, with a 99.6% probability. Conclusion: The cost-effectiveness analysis suggested that from the Chinese healthcare system perspective, the switch maintenance regimen at current price is unlikely to be an advantageous regimen in terms of cost-effectiveness for patients with advanced HER2-negative gastric or GEJC at a willingness-to-pay threshold of ¥287,247/QALY.