Efficacy and safety of bintrafusp alfa evaluated in a phase II single-arm clinical trial in previously treated advanced pleural mesothelioma

Abstract

Objectives

We aimed to evaluate the efficacy (progression-free survival [PFS]) of bintrafusp alfa in patients with pleural mesothelioma (PM) who had progressed to platinum-based chemotherapy and had not previously received immunotherapy. We also assessed overall survival [OS], objective response rate [ORR], and safety and tolerability.

Materials and Methods

This open-label, non-randomised, multicentre, phase II, single-arm clinical trial was carried out by the Spanish Lung Cancer Group between October 2021 and March 2023 in 15 Spanish hospitals. We included patients ≥ 18 years old, with an ECOG PS of 0 or 1, with a histologically confirmed unresectable or metastatic PM, and with a life expectancy of at least three months.

Results

46 patients were included in the analysis. Most patients were men (78.3 %), the mean age was 70.0 years (SD, 9.5), and most presented epithelioid PM (84.8 %). The median PFS was 1.9 months (95 % CI, 1.7–3.2 months), the median duration of bintrafusp alfa response was 3.8 months, and the ORR was 6.5 % (95 % CI, 2.1–18.8 %). The median OS was 11.9 months (95 % CI, 5.8–15.7 months). Grade 3 or higher adverse events were observed in 34.8 % of patients and no grade 5 adverse event was reported.

Conclusion

Bintrafusp alfa did not reach the expected efficacy in patients with advanced PM. We did not identify new safety signals with bintrafusp alfa, and no case of bleeding was reported. Our study suggested that bintrafusp alfa has limited efficacy in PM, as reported in other solid tumours.