Abstract 2797: Multicenter pharmacokinetic study of pembrolizumab for non-small cell lung cancer in older adults aged over 75 years

Background: Pembrolizumab (Pemb) is a key drug for the treatment of advanced or recurrent non-small cell lung cancer (NSCLC). However, there are limited data on Pemb use in older adults aged >75 years with NSCLC, especially in terms of pharmacokinetics (PK). Methods: This open-label multicenter observational study aimed to evaluate real-world data on the safety, efficacy, and blood concentrations of Pemb (both monotherapy and combination therapies) in older adults with NSCLC. Blood samples for PK analysis were collected immediately before Pemb administration. Quantitative Pemb concentrations were measured by liquid chromatography-mass spectrometry. Results: We enrolled 100 patients from July 2019 to September 2020; one patient was excluded due to stage migration. Patient characteristics were as follows: median age, 78 (75-87) years; male/female ratio, 70/29; performance status (PS) 0-1/2-3, 85/14; adenocarcinoma/squamous cell carcinoma/others, 62/25/12; stage I-III/IV/postoperative recurrence (TNM 7th edition), 9/60/30; PD-L1 TPS 75 years with NSCLC and low albumin levels and PS and a high number of metastatic organs, C1 trough of Pemb is reduced and not expected to prolong PFS and OS. Citation Format: Yoshiro Nakahara, Kageaki Watanabe, Yukio Hosomi, Yuta Yamanaka, Takayasu Kurata, Hidehito Horinouchi, Yuichiro Ohe, Tetsuhiko Asao, Sho Saeki, Yukari Tsubata, Yu Fujita, Jun Sakakibara Konishi, Hidenori Mizugaki, Mayu Ohuchi, Shigehiro Yagishita, Akinobu Hamada. Multicenter pharmacokinetic study of pembrolizumab for non-small cell lung cancer in older adults aged over 75 years [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular a