A randomized phase II study of cabiralizumab (cabira) + nivolumab (nivo) ± chemotherapy (chemo) in advanced pancreatic ductal adenocarcinoma (PDAC).

TPS465Background: Treatment options for PDAC are limited; thus, new therapies that can improve outcomes and extend survival are needed. PDAC is associated with high infiltration by tumor-associated macrophages (TAMs) that inhibit antitumor T-cell activity. Blocking colony-stimulating factor 1 receptor (CSF-1R) signaling—which supports the recruitment, differentiation, and maintenance of immunosupressive macrophages in tumors—may lead to depletion of TAMs and upregulation of T-cell checkpoints. Cabira, a humanized IgG4 monoclonal antibody, binds to CSF-1R and blocks its signaling, a key determinant of TAM activation and survival. By reducing TAMs and promoting a proinflammatory microenvironment, cabira may stimulate T-cell responses, thereby sensitizing PDAC to therapy with nivo (anti‒PD-1). In a phase 1a/b study cabira + nivo was tolerable and showed evidence of on-target tumor immune modulation and durable clinical benefit in heavily pretreated patients (pts) with advanced PDAC (Wainberg et al. J Immunot...