OM336 in Sensitized Transplant Candidates

This investigator-initiated, single-arm, open-label Phase IIa pilot study will evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary efficacy of OM336 in highly HLA-sensitized adults with chronic kidney disease awaiting kidney transplantation. The study will enroll 12 participants who have either a very low likelihood of receiving a compatible deceased donor kidney because of broad HLA sensitization or unacceptable donor-specific antibodies against a potential living donor. Participants will receive one 4-week course of subcutaneous OM336, with the option of a second 4-week course based on the change in virtual panel-reactive antibody (vPRA) levels after the initial treatment period. Participants will subsequently be followed for up to 24 months and, if transplantation occurs, for at least 12 months after transplantation. The primary objectives are to evaluate the safety and tolerability of OM336 through Week 24 and (co-primary endpoint) its effect on HLA sensitization, assessed by changes in vPRA levels at Week 24. Secondary and exploratory objectives include assessment of the durability of changes in vPRA and donor-specific antibodies, the number of potential compatible donors, transplantation rates, OM336 pharmacokinetics and immunogenicity, and effects on B-cell and plasma-cell immunity and antibody characteristics. An optional substudy will assess B-cell immunity in bone marrow and lymph-node samples.