Specific issues related to the use of monoclonal antibodies — rituximab and eculizumab – in patients after kidney transplantation

There are specific indications to use modern monoclonal antibodies in selected patients after kidney transplantation, such as desensitization, treatment of humoral rejection, management of post-transplant recurrence of nephrotic syndrome, therapy of lymphoproliferative disease (PTLD) for rituximab, and a prophylaxis/treatment of recurrence of the atypical hemolytic uremic syndrome (aHUS) for eculizumab. The use of rituximab, a depleting antibody against BCD20 cells is related to hypogammaglobulinemia and late-onset neutropenia, which increases the risk of secondary viral, bacterial, and fungal infections. Pneumocystis jiroveci-related pneumonia is the most severe complication. Eculizumab, as a blocker of the complement system, predominantly increases the risk of meningococcal infections; however, some associations with other types of infections, like cryptococcal and JC-virus-related infections have also been reported. The use of both monoclonals includes specific mandatory prophylaxis, with trimethoprim/sulfamethoxazole (TMP-SMX) in rituximab and anti-meningococcal vaccination/penicillin administration in eculizumab-treated patients. There are specific issues associated with the use of both monoclonals in terms of COVID-19-related infections, as administration of rituximab is related to the prolonged failure of response to relevant vaccinations (including the third, booster dose), whereas blocking of the complement system may ameliorate the COVID-19-infection-related cytokine storm