Abstract LB061: On-target peripheral and tumor immune microenvironment modulation in patients treated with lacnotuzumab (anti-CSF1, MCS110) + spartalizumab

Abstract Background: The CSF-1/CSF-1R (colony-stimulating factor-1) pathway plays a significant role in the tumor microenvironment via regulation of tumor-associated macrophages (TAMs). Lacnotuzumab (MCS110) is a humanized monoclonal antibody against CSF-1. Lacnotuzumab may counteract the tumor suppressive microenvironment induced by CSF-1, potentially enhancing the efficacy of PD-1 inhibition. Methods: MCS110Z2102 is a phase 1b/2 study in cancer patients with advanced malignancies treated by lacnotuzumab combined with the PD-1 inhibitor spartalizumab. Eligible patients with previously treated advanced/metastatic solid tumors received 1, 3, 5, 7.5 and 10 mg/kg intravenous doses of lacnotuzu…