Detalle de: Comparative effectiveness of two alternative dosing strategies of pembrolizumab in metastatic non-small-cell lung cancer in a real-world setting

Background Pembrolizumab, a PD-1 immune checkpoint inhibitor, has become a standard first-line treatment for metastatic non-small cell lung cancer (mNSCLC), administered either as monotherapy or combined with platinum-based chemotherapy. Although current guidelines endorse a fixed dose of 200 mg every three weeks, initial clinical studies supported a weight-based dosing strategy (2 mg/Kg). The comparative effectiveness of these dosing strategies in real-world settings remains unclear. Methods A multicenter, retrospective cohort study was conducted across three universitary hospitals to compare the effectiveness of two pembrolizumab dosing regimens as first line treatment in patients with mNSCLC. Patients were divided into two groups: the standard-dose group (STD, ≤ 2 mg/Kg) and high-dose group (HD, > 2 mg/Kg), both administered every 3 weeks. Primary endpoints were progression-free survival (PFS) and overall survival (OS). Kaplan-Meier and Cox regression analyses were used to compare outcomes between dosing groups. Results Among 198 patients analyzed, baseline characteristics were similar between groups, except for a higher proportion of ECOG 0 in the HD group. Median PFS was 14.9 months in the STD group versus 8.3 months in the HD group, without statistical significance (HR 1.27, 95% CI 0.87-1.86, p = 0.215). Similarly, median OS was numerically longer in the STD group (27.7 months) compared to the HD group (17.3 months) (HR 1.39, 95% CI 0.97-2.03, p = 0.072). Rates of treatment discontinuation due to adverse events were similar between groups. Conclusions In this real-world cohort of mNSCLC patients, pembrolizumab administered at 2 mg/Kg every three weeks appears to provide similar progression free survival and overall survival outcomes compared to higher doses. These findings support the clinical effectiveness of lower pembrolizumab doses, aligning with prior pharmacokinetic and clinical studies indicating a lack of dose-response relationship for PD-1 inhibitors in mNSCLS, potentially optimizing treatment cost without compromising survival outcomes.