Key clinical point : Pembrolizumab offers potent and sustained efficacy with an acceptable safety profile in heavily pretreated patients with relapsed or refractory primary mediastinal B-cell lymphoma (PMBCL).
Major finding: After a median follow-up of 48.7 months, the median progression-free survival and overall survival were 4.3 (95% CI 2.8-13.8) months and 22.3 (95% CI 7.3-not reached) months, respectively. The objective response rate was 41.5%. Grade 3 or 4 treatment-related adverse events occurred in 22.6% of patients.
Study details: Findings are from the final analysis of the phase 2 KEYNOTE-170 trial including 53 adult patients with relapsed or refractory PMBCL whose disease progressed after or who were ineligible for (after ≥2 prior lines of therapy) autologous stem cell transplantation and received pembrolizumab every 3 weeks for up to 2 years.
Disclosures: The KEYNOTE-170 trial was funded by Merck Sharp & Dohme (MSD). Some authors reported ties with various organizations, including MSD. Three authors declared being employees of and holding stock or stock options in MSD.
Source: Zinzani PL et al. Pembrolizumab in relapsed or refractory primary mediastinal large B-cell lymphoma: Final analysis of KEYNOTE-170. Blood. 2023 (May 2). Doi: 10.1182/blood.2022019340