Daratumumab and Belatacept for Desensitization

This study will enroll 15 eligible adult participants with end stage renal failure on dialysis who are on the waiting list for a deceased donor transplant with calculated panel reactive antibodies (cPRA) ≥99.9% or \>98% (with \>5 years of waiting time) or, those with cPRA \>98% and an human leukocyte antigen (HLA)-incompatible approved living donor who have not received a transplant after 1 year in a paired kidney exchange program. The study will evaluate whether the study treatment is safe and can lower the participant's immune system's sensitization to kidney donors, making it easier to find a well-matched kidney for them.

The study treatment is comprised of two drugs, Darzalex® (daratumumab) and Nulojix® (belatacept). Daratumumab is licensed for treatment of multiple myeloma and belatacept is licensed for prevention of rejection after kidney transplant. Eligible participants will receive infusions of daratumumab and belatacept over a 10-week period in Cohort 1. Eligible participants will receive infusions of daratumumab and belatacept over a 14-week period in Cohort 2. An interim safety and efficacy analysis will occur after the first 5 participants have received study treatment. All subjects will undergo HLA antibody assessments and bone marrow aspiration prior to and after completion of treatment and receive 42 weeks of follow up after completing treatment. Participants who prematurely discontinue study therapy will receive follow up through 56 weeks after their baseline visit. Subjects who receive a kidney transplant while in the study will receive standard of care immunosuppression and undergo 52 weeks of follow up. Living donors will participate for one study visit to provide blood collection.