Interim results analysis of the PERFECTION observational study in patients with metastatic non-small cell lung cancer

Aim. To evaluate the efficacy and safety profile of the pembrolizumab biosimilar, Pembroria, in patients with advanced lung cancer in routine clinical practice. Materials and methods. The patients eligible for pembrolizumab therapy based on standard clinical indications and without contraindications participated in the multicenter, multicohort, post-marketing, prospective, non-interventional study. The primary endpoint was the best objective response rate (ORR) assessed within six months of treatment initiation. This report presents interim analysis for patients with non-squamous non-small cell lung cancer (nsNSCLC) and squamous non-small cell lung cancer (sNSCLC) using Fleming’s two-stage single-arm design (stages g1 and g2). Thresholds for hypothesis testing and sample size determination were based on established literature benchmarks. Results Non-squamous NSCLC. Stage g1 enrolled 20 patients with a median age of 64 years. The follow-up period for assessing the best objective response was 2.57 months. An objective response was achieved in 55% (11/20) of patients, meeting predefined efficacy criteria at stage g1. Squamous NSCLC. Stage g1 included 23 patients and based on the results of stage g1, the study proceeded to stage g2 with the enrollment of an additional 23 patients in stage g2, yielding a total of 46 participants with a median age of 66 years. An ORR of 47.8% (22/46) was observed, confirming efficacy of the pembrolisumab biosimilar at stage g2. The median follow-up period to the objective response assessment was 2.88 months. Across the six-month follow-up period, nine adverse events (AEs) were reported among seven patients (8.4%) in the NSCLC cohort. Four AEs were considered therapy-related and classified as Grade 2 per CTCAE v5.0. No AEs Grade 4/5 were recorded. Conclusion. In the NSCLC cohort, the pembrolizumab biosimilar (Pembroria) has demonstrated an ORR comparable to that of the reference pembrolizumab reported in clinical trials for both nsNSCLC and sNSCLC, regardless of PD-L1 expression levels or pembrolizumab treatment regimens. These findings support the real-world efficacy and safety of Pembroria in a diverse patient population.