IVIg Monotherapy for Desensitization in Highly Sensitized Kidney Transplant Candidates: Efficacy and Long-Term Outcomes

Background: Highly sensitized (HS) patients awaiting kidney transplantation often face prolonged waiting times and increased mortality, especially in regions lacking structured organ allocation directed to these patients or desensitization strategies. This study evaluated the efficacy and safety of intravenous immunoglobulin (IVIg) monotherapy for desensitization (DS) in HS patients awaiting deceased donor kidney transplantation. Methods: Thirty-nine sensitized patients on the deceased donor waiting list with > 5 positive T/B-cell complement-dependent cytotoxicity crossmatches (CDC-XM) received IVIg at 2 g/kg/month. Patients were followed for a mean of 58.9 ± 22.9 months. Outcomes included transplantation rates, changes in calculated panel-reactive antibodies (cPRA), donor-specific antibody (DSA) levels, and post-transplant survival. Results: Fourteen patients (35.9%) underwent transplantation, with 64.3% exhibiting detectable DSA. Post-DS waiting time on the WL decreased significantly (75 ± 41 vs. 20 ± 11 months; p < 0.01). IVIg therapy significantly reduced class I cPRA (p = 0.0074), class II cPRA (p = 0.04), total anti-HLA antibodies, and immunodominant DSA levels in transplanted patients (p = 0.03). Transplantation rates were higher among patients prioritized due to dialysis access failure (70% vs. 21%; p < 0.003). Three-year patient survival was 78.6%, and death-censored graft survival was 76.4%. Antibody-mediated rejection (ABMR) occurred only in recipients with > 1 DSA at the time of transplantation (p = 0.02). No serious IVIg-related adverse events were observed. Conclusions: IVIg monotherapy is a safe and effective desensitization strategy for HS patients, significantly reducing anti-HLA antibodies and time on WL, thereby facilitating access to deceased donor kidney transplantation.