This is a pilot exploratory, proof of concept, open-label, single-center phase II investigator initiated clinical trial entitled IXAzomib for DESensitization (IXADES). The purpose of the study is (1) to examine the safety and efficacy of ixazomib for desensitization of highly sensitized kidney transplant candidates and (2) to conduct mechanistic studies to address the role of HLA and non-HLA antibodies, T and B cell phenotypes, and BAFF/APRIL in immune monitoring of sensitized kidney transplant candidates.~Specific Aim 1. To determine the safety and efficacy of ixazomib as a desensitization strategy. There is currently no effective desensitization strategy for highly sensitized patients defined as calculated Panel of Reactive Antibodies (cPRA) ≥ 80%. For this study, 10 highly sensitized kidney transplant candidates on the waitlist for more than 24 months will receive ixazomib 3 mg (and dexamethasone 20 mg) on days 1, 8, and 15 of a 28 cycle for 12 months. The primary objective is to evaluate the safety (distal neuropathy, thrombocytopenia, and gastrointestinal symptoms) and efficacy (decline in cPRA > 20%) of ixazomib. The secondary efficacy endpoint is transplantation rate within 12 months of therapy.~Specific Aim 2. Identify immune indices which predict the course of disease and/or response to treatment in highly sensitized patients. Mechanistic studies will use bone marrow and blood obtained from subjects in Aim 1 to determine the effect of treatment on immune regulation and reconstitution after therapy. Since the bone marrow microenvironment produces BAFF/APRIL and supports plasma cell maturation,the effect of therapy on the generation of BAFF/APRIL will be determined by bone marrow mesenchymal stem cells and the survival of bone marrow-derived plasma cells after desensitization. Specifically it's proposed to:~Identify if bone marrow plasma cells, IgG subsets, and levels including free light chains, and circulating BAFF/APRIL predict outcomes.~Determine if treatment is effective in downregulating circulating BAFF/APRIL and anti-HLA, endothelin-1 type A receptor (ETAR), angiotensin type 1 receptor (AT1R), and complement fixing C1q antibodies.
The purpose of this research study is to find out how well ixazomib (the study drug) works to desensitize highly sensitized kidney transplant recipients.