ABSTRACT
BACKGROUND: Focal segmental glomerulosclerosis (FSGS) is a common cause of end-stage kidney disease and frequently recurs after kidney transplantation. Recurrent FSGS (rFSGS) is associated with poor allograft and patient outcomes. Bleselumab, a fully human immunoglobulin G4 anti-CD40 antagonistic monoclonal antibody, disrupts CD40-related processes in FSGS, potentially preventing rFSGS. METHODS: A phase 2a, randomized, multicenter, open-label study of adult recipients (aged ≥18 y) of a living or deceased donor kidney transplant with a history of biopsy-proven primary FSGS. The study assessed the efficacy of bleselumab combined with tacrolimus and corticosteroids as maintenance immunosuppression in the prevention of rFSGS >12 mo posttransplantation, versus standard of care (SOC) comprising tacrolimus, mycophenolate mofetil, and corticosteroids. All patients received basiliximab induction. The primary endpoint was rFSGS, defined as proteinuria (protein-creatinine ratio ≥3.0 g/g) with death, graft loss, or loss to follow-up imputed as rFSGS, through 3 mo posttransplant. RESULTS: Sixty-three patients were followed for 12 mo posttransplantation. Relative decrease in rFSGS occurrence through 3 mo with bleselumab versus SOC was 40.7% (95% confidence interval, -89.8 to 26.8; P = 0.37; absolute decrease 12.7% [95% confidence interval, -34.5 to 9.0]). Central-blinded biopsy review found relative (absolute) decreases in rFSGS of 10.9% (3.9%), 17.0% (6.2%), and 20.5% (7.5%) at 3, 6, and 12 mo posttransplant, respectively; these differences were not statistically significant. Adverse events were similar for both treatments. No deaths occurred during the study. CONCLUSIONS: In at-risk kidney transplant recipients, bleselumab numerically reduced proteinuria occurrence versus SOC, but no notable difference in occurrence of biopsy-proven rFSGS was observed.
ABSTRACT
This study assessed the efficacy and safety of the anti-CD40 monoclonal antibody bleselumab (ASKP1240) in de novo kidney transplant recipients over 36 months posttransplant. Transplant recipients were randomized (1:1:1) to standard of care (SoC: 0.1 mg/kg per day immediate-release tacrolimus [IR-TAC]; target minimum blood concentration [Ctrough ] 4-11 ng/mL plus 1 g mycophenolate mofetil [MMF] twice daily) or bleselumab (200 mg on days 0/7/14/28/42/56/70/90, and monthly thereafter) plus either MMF or IR-TAC (0.1 mg/kg per day; target Ctrough 4-11 ng/mL days 0-30, then 2-5 ng/mL). All received basiliximab induction (20 mg pretransplant and on days 3-5 posttransplant) and corticosteroids. One hundred thirty-eight transplant recipients received ≥1 dose of study drug (SoC [n = 48]; bleselumab + MMF [n = 46]; bleselumab + IR-TAC [n = 44]). For the primary endpoint (incidence of biopsy-proven acute rejection [BPAR] at 6 months), bleselumab + IR-TAC was noninferior to SoC (difference 2.8%; 95% confidence interval [CI] -8.1% to 13.8%), and bleselumab + MMF did not demonstrate noninferiority to SoC (difference 30.7%; 95% CI 15.2%-46.2%). BPAR incidence slightly increased through month 36 in all groups, with bleselumab + IR-TAC continuing to demonstrate noninferiority to SoC. Bleselumab had a favorable benefit-risk ratio. Most treatment-emergent adverse events were as expected for kidney transplant recipients (ClinicalTrials.gov NCT01780844).
