Real‐world data on efficacy/safety and economic impact of nivolumab administered every 2 and 4 weeks among Japanese patients.

Aim: A new treatment interval for nivolumab administration at 480 mg every 4 weeks, in addition to 240 mg every 2 weeks, was approved in Japan in 2020. Using model‐based evaluation, it was speculated that the effects or safety of nivolumab do not differ between the two treatment intervals; however, real‐world data on nivolumab efficacy, safety, and economic impact are lacking. Accordingly, we aimed to examine the effects of nivolumab treatment intervals (2 weeks vs. 4 weeks) in terms of efficacy, safety, and economic impact in Japanese patients with cancer. Methods: We retrospectively analyzed 126 patients treated with nivolumab. The patients were divided into two groups depending on whether they received nivolumab at 240 mg every 2 weeks (2‐week group) or 480 mg every 4 weeks (4‐week group). Results: Efficacy results found no significant difference between the 4‐ and 2‐week groups considering median overall survival (p = 0.70) and median progression‐free survival (p = 0.57). The incidence of any grade and ≥ grade 3 immune‐related adverse events did not differ between the 4‐week and 2‐week groups (any grade, p = 0.13; ≥ grade 3, p = 0.36). Excluding drug costs, the 4‐week group had significantly lower medical costs than the 2‐week group (2‐week vs. 4‐week: mean, 94,659 JPY [679.0 USD] vs. 58,737 JPY [421.3 USD]; p < 0.05). Conclusion: Collectively, our findings suggest that nivolumab 480 mg every 4 weeks may be more effective than nivolumab 240 mg every 2 weeks in terms of economic impact. [ABSTRACT FROM AUTHOR]