BerGenBio ASA announced that an oral presentation detailing the initial results from a Phase IIa trial evaluating bemcentinib in patients with mesothelioma was presented on June 5, 2023 at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. The abstract, Bemcentinib and pembrolizumab in patients with relapsed mesothelioma: MiST3, a phase IIa trial with cellular and molecular correlates of efficacy, was presented by the study lead investigator, Dr. Matthew Krebs, Ph.D., FRCP, The University of Manchester, UK. MiST, the Mesothelioma Stratified Therapy umbrella trial, led by Professor Dean Fennell at the University of Leicester, UK, is a British Lung Foundation funded study dedicated to improving survival outcomes for patients with mesothelioma.

MiST3, the third arm of the trial, was designed to assess the efficacy of AXL/PD-1 inhibition with the combination of BerGenBio's AXL inhibitor bemcentinib and pembrolizumab. 26 patients with relapsed mesothelioma were enrolled in MiST3 and all received at least one dose of bemcentinib and pembrolizumab. The primary endpoint of disease control rate at 12 weeks (DCR12w) was met: 46.2% (90% CI: 29.2, 63.4).

Secondary endpoints included a disease control rate at 24 weeks (DCR24w) of 38.5% (95% CI: 20.2, 59.4) and an overall response rate of (ORR) of 15.4% (95% CI: 4.4, 34.9). The combination of bemcentinib and pembrolizumab was generally safe and well-tolerated.