636. Meningococcal Vaccination and Antibiotic Prophylaxis Practices in Solid Organ Transplant Recipients undergoing Eculizumab Therapy

Abstract Background Eculizumab, an inhibitor of terminal complement activation, has been utilized in pre-transplant desensitization, treatment of antibody-mediated rejection and thrombotic microangiopathy in solid organ transplant recipients (SOTR). Eculizumab is associated with meningococcal disease, leading to guidelines for vaccination against serogroups ACWY (menACWY) and B (menB) at least 2 weeks prior to eculizumab therapy. In persons requiring emergent use of eculizumab, prophylaxis for at least 2 weeks is recommended. SOTRs respond suboptimally to vaccination, raising consideration for pre-transplant vaccination and prolonged prophylaxis in those undergoing eculizumab therapy. We sought to describe meningococcal vaccination and prophylaxis practices among SOTRs receiving eculizumab. Methods We performed a retrospective chart review of meningococcal vaccination, including number and timing pre- or post-transplant, along with prophylaxis prescribing and duration in SOTRs receiving eculizumab across 3 distinct Mayo Clinic Enterprise sites (Rochester, Arizona, and Florida). Results 200 SOTRs receiving at least one dose of eculizumab between 1/1/2008 and 9/16/2021 were reviewed. Eculizumab indications included antibody mediated rejection (38%), desensitization (26%), and thrombotic microangiopathy (19%). 83% (166/200) of SOTRs received eculizumab for an unanticipated post-transplant complication. Vaccination rates were 82% (164/200) and 35.5% (71/200) for menACWY dose 1 and 2, respectively, and 54% (108/200) and 28.5% (57/200) for menB dose 1 and 2, respectively. The majority received their first vaccination post-transplant: menACWY 66.5% (133/200) and menB 2.5% (185/200). Among those without vaccination pre-eculizumab, 22.3% (41/184) were not prescribed prophylaxis. The median duration of prophylaxis was 62 (range 4-2651) days. Conclusion Most SOTRs underwent meningococcal vaccinations near the time of eculizumab administration post-transplant for an unanticipated complication. One-fifth of those meeting criteria were not provided meningococcal prophylaxis. These findings may support pre-transplant administration of meningococcal vaccinations and heightened awareness for meningococcal prophylaxis in SOTRs receiving eculizumab. Disclosures All Authors: No reported disclosures.