Ramucirumab Beyond Disease Progression After Paclitaxel Plus Ramucirumab in Gastric Cancer: A Phase II Trial

Background/Aim: Irinotecan monotherapy was the most widely used third-line chemotherapy for unresectable advanced or recurrent gastric cancer in Japan until the approval of nivolumab in September 2017 and trifluridine/tipiracil in August 2019. The benefit of continuing ramucirumab with irinotecan, an anti-VEGFR-2 monoclonal antibody, after the failure of paclitaxel plus ramucirumab (PTX+RAM) as secondline chemotherapy, has been under debate. Patients and Methods: A single-center phase II study was conducted in patients with unresectable advanced or recurrent gastric cancer previously treated with fluoropyrimidines and platinum, who received PTX+RAM as second-line therapy and irinotecan plus ramucirumab (IRI+RAM) as third-line therapy after treatment failure (UMIN000022956). Results: Eleven patients were enrolled from July 2016 to July 2018. Enrolment was discontinued due to difficulties in case ascertainment because of expanded third-line treatment options (originally planned for 53 patients). The median progression-free survival (the primary endpoint) of the IRI+RAM was 3.98 months [95% confidence interval (CI)=1.78-NA]. Among secondary endpoints, the transition rate to IRI+RAM was 45%, the rate of 8-week treatment continuation for IRI+RAM was 100%, the response rate for IRI+RAM was 0%, the median overall survival (OS) for PTX+RAM was 13.53 months (95%CI=1.61-24.36), and the median OS for IRI+RAM was 9.99 months (95CI=4.5-NA). Conclusion: The transition rate from PTX+RAM to IRI+RAM was reasonable. Ramucirumab beyond progressive disease may be beneficial for patients who are able to transition to IRI+RAM.