#4774 the Use of Regdanvimab for the Prevention of Severe Covid-19 in Patients on Hemodialysis

Abstract

Background and Aims A new coronavirus infection has become a serious threat leading to increased mortality worldwide. COVID-19 is an acute airborne disease caused by severe acute respiratory syndrome virus (SARS-Cov-2). Evolution of the virus, emergence of new mutant strains, changes in virulence dictate the need to search for new tools both in treatment and prevention of severe disease. The aim of our study was evaluation of the efficacy of Regdanvimab (Regkirona, Samsung BioLogics) to prevent severe COVID-19 in patients receiving ambulatory hemodialysis in the period of increasing morbidity. Method The study included 20 patients on program hemodialysis, mean age 54.9±17.6 years, vaccinated or who underwent COVID-19 more than six months ago. All subjects of the study received Regkirona at a standard dose of 40 mg/kg of body weight intravenously once at the end of the hemodialysis procedure after the physician assessed the feasibility of prophylaxis. All subjects were assessed for humoral immunity before Regkirona administration and after Regkirona administration according to the level of total SARS-CoV-2 IgG and IgG antibodies to the subunit of the S1 receptor-binding domain of the SARS-CoV-2 protein. Results Total SARS-CoV-2 IgG level and IgG level of antibodies to SARS-CoV-2 receptor-binding subunit S1 was 83.9±69.5 U/ml and 260.7±199.5 BAU/ml respectively before drug administration. During the 6-month follow-up period from July to November 2022, which paralleled the next round of increased morbidity, four patients with SARS-CoV-2 PCR test positive reported mild to moderate symptoms of SARS (marked weakness, fever, loss of smell, catarrhal symptoms, cough, shortness of breath, and chest pain unassociated with other causes). None of the subjects required hospitalization. We evaluated IgG antibody titers to the receptor-binding domain of the SARS-CoV-2 protein subunit S1 after 1, 3 and 6 months and demonstrated a nonlinear decline titers from 5104±2257.1 BAU/ml, 1988.7±1440.4 BAU/ml to 407,0±350,2 BAU/ml respectively, which may indirectly reflect short half-life of Regkirona. Conclusion The results of our study showed the efficacy of Regdanvimab to prevent the severe disease of COVID-19 in high-risk patients during the period of rising morbidity.