BMS-986178

P1, N=15, Active, not recruiting, Ronald Levy | Trial completion date: Oct 2023 --> Oct 2024 | Trial primary completion date: Oct 2023 --> Oct 2024

STUDY: Fourteen patients with low-grade lymphoma received low-dose (2Gy x 2) radiotherapy to a single tumor site followed by 5 weekly intratumoral injections of 2 mg CpG-ODN (SD-101, TriSalus Life Sciences) and 3.75 mg anti-OX40 antibody into the same site...This loss was reproduced by in vitro assays where activated blood CD4 T cells exhibited a loss of cell surface OX40 when cultured with BMS-986178... Our observations suggest that treatment with an agonistic anti-OX40 antibody induced a loss of OX40 on the cell surface of effector CD4 T cells in the tumor microenvironment. Fewer molecules of OX40 receptor may have constrained the efficacy of subsequent anti-OX40 infusions and may explain why the clinical responses observed in this study were lower than observed in our past clinical trials of in situ vaccination.

Using a hybridoma platform and three different types of immunization strategies, namely recombinant protein, DNA, and overexpressing cells, we identified a chimeric anti-OX40 antibody (mAb035-hIgG1 from DNA immunization) that shows excellent binding specificity, and slightly stronger activation of human memory CD4 T cells and similar potent anti-tumor activity compared to BMS 986178, an anti-OX40 antibody currently being evaluated for the treatment of solid tumors. This paper further systematically investigates the antigen-specific immune response, the number of binders, epitope bins, and functional activities of antibodies among different immunization strategies. Interestingly, we found that different immunization strategies affect the biological activity of monoclonal antibodies.

Our results highlight the value of an integrated translational approach applied during early clinical development to aggregate preclinical and clinical data in an effort to define the optimal dose and schedule for T-cell agonists in the clinic.