Real-world sequential treatment patterns and outcomes in the new era of immunotherapy for advanced gastric cancer in Japan.

BACKGROUND

We investigated treatment patterns and outcomes in patients with advanced gastric cancer (AGC) after nivolumab first-line therapy approval in Japan in 2021.

METHODS

This retrospective study used data from the Medical Data Vision database. Treatment patterns were described. Overall time-to-treatment discontinuation (TTD) from the start of each line was estimated.

RESULTS

Among 11,276 included patients, 1589 received anti-HER2+chemotherapy (Cx) at any line and regarded as HER2-positive AGC (anti-HER2+Cx group). Among the other, 9687 who presumably had HER2-negative AGC, 5722 received nivolumab+Cx at first-line (Nivo+Cx group), and 3965 received Cx alone at first-line (Cx group). Nivolumab+S-1+oxaliplatin (4,104/11,276; 36.4%) was the most common first-line regimen. The most common second-line and third-line regimens were ramucirumab+paclitaxel (PTX) (or NabPTX) (3092/4345; 71.2%) and nivolumab (490/1712; 28.6%). Median overall TTD from start of first-line therapy was 13.3, 10.5, and 6.8 months in anti-HER2+Cx, Nivo+Cx, and Cx groups. Median overall TTD from start of second-line therapy was 6.2, 3.5, and 4.9 months with ramucirumab combination therapy, ramucirumab monotherapy, and other therapies.

CONCLUSIONS

After first-line nivolumab was introduced for AGC in Japan, treatment patterns remained consistent with Japanese Gastric Cancer Association guidelines. Optimizing sequential therapy, including nivolumab at first-line and ramucirumab combination at second-line, may improve outcomes.