Early First-Line Bortezomib for Acute Antibody-Mediated Rejection: A Retrospective Review of Long-Term Outcomes From a Uniform Single-Center Protocol.

BACKGROUND: Antibody-mediated rejection (ABMR) is a major complication of kidney transplantation. With the current standard of care, long-term graft survival is poor. Optimal treatment remains uncertain, and various protocols are being used. Bortezomib has been previously proposed as a candidate for ABMR treatment, but its use is not widely accepted as a first-line treatment. Possible reasons why bortezomib treatment has not gained popularity may be related to the treatment not showing efficacy when used in chronic rejection or the practice of using bortezomib only after failure of treatment with other agents. METHODS: This report is a retrospective description of a single-center experience with bortezomib as a first-line adjunctive anti-plasma cell therapy in 10 consecutive kidney transplant recipients with ABMR. Only patients with biopsy-proven ABMR were included. RESULTS: All patients received a uniform immunosuppression protocol. The median time from transplantation to ABMR diagnosis was 14 days (range 5-650 days). Eight of the 10 patients responded well to treatment. No significant complications were observed. In long-term follow-up (up to 7.6 years, median 53 months, range 24-91 months), 8 of the 10 kidneys are still functioning with a median eGFR of 60 mL/min (range 35-80 mL/min/1.73m2). Study limitations include a retrospective design and the small number of patients. CONCLUSIONS: Our cohort extends prior evidence by focusing on early, first-line adjunctive bortezomib with a uniform protocol and long follow-up. Given the cumulative reports of the successful use of bortezomib in acute ABMR, there may be a role for implementing its routine use, along with current treatment modalities.