Real-world safety and effectiveness of nivolumab in patients with cancer of unknown primary: results from a nationwide post-marketing surveillance in Japan
A prospective observational study demonstrates favorable antitumor response and manageable safety with nivolumab in cancer of unknown primary, supporting its routine clinical use.
Key Points
To evaluate the real-world safety and effectiveness of nivolumab in Japanese patients treated for cancer of unknown primary in routine practice.
Prospective, multicenter observational post-marketing surveillance conducted across 66 institutions in Japan (jRCT2041240121).
Included patients initiating nivolumab between April 2022 and June 2023 followed for 6 months, assessing a safety set (N=151) and an effectiveness set (N=144).
Any-grade and Grade ≥ 3 treatment-related adverse events occurred in 25.2% and 11.9% of patients, respectively, most commonly interstitial lung disease (3.3%), abnormal hepatic function (2.6%), and hypothyroidism (2.6%), alongside one fatal neutropenia event.
The overall response rate was 21.5% overall, with higher rates observed in patients without prior systemic therapy (25.4% vs. 18.2%) and those with lymph node-only involvement (36.6% vs. 15.5%).
The 6-month overall survival rate was 71.0%, and median overall survival was not reached during the 6-month follow-up period.