Efficacy and safety of regdanvimab in patients with mild/moderate COVID-19 and high risk of progression of the disease: a retrospective study in a short-term stay unit
Authors: Mаrkina Ulyana A. , Fomina Daria S. , Lebedkina Marina S. , Kruglova Tatiana S. , Chernov Anton A. , Zagrebneva Alena I. , Mutovina Zinaida Yu. , Karaulov Alexander V. , Alexeeva Ekaterina I. , Lysenko Mariana A. 
Published: June 2022

Background. The use of virus-neutralizing monoclonal antibodies is an effective method of etiotropic therapy for SARS-CoV-2 in patients of high-risk groups of severe COVID-19. Regdanvimab is a single-component monoclonal antibodies immunoglobulin G1, whose mechanism of action is aimed at binding SARS-CoV-2 virus at the RBD site of the spike protein S1 domain. In the Russian Federation, regdanvimab is approved for emergency administration in COVID-19 for adult patients not requiring respiratory therapy who are at high risk of developing a severe course of the disease.
Aim. To evaluate the efficacy and safety of therapy with regdanvimab in patients with mild/moderate COVID-19 in a short-term hospital unit.
Materials and methods. Virus-neutralizing therapy with regdanvimab was performed at the short-term hospital unit of the Moscow City Clinic. An open retrospective observational single-center study included 92 adult patients with mild/moderate coronavirus infection. All patients had comorbid chronic diseases and belonged to the high-risk group for the development of a severe COVID-19. Inclusion criteria: age 18 to 75 years; presence of a verified diagnosis of COVID-19 of mild/moderate COVID-19, polymerase chain reaction (PCR) confirmed; one or more chronic diseases; first 7 days from the onset of the first symptoms of COVID-19 (including day 7). Exclusion criteria: need for oxygen support. Clinical efficacy was assessed according to the World Health Organization Сlinical Progression Scale and supplemented with laboratory markers at baseline and in dynamics, as well as with monitoring of virus elimination by PCR.
Statistics. Calculations were performed using the statistical computing environment R 4.1.3 (R Foundation for Statistical Computing, Austria). For quantitative indices the median (1; 3 quartiles) was indicated. For binomial signs we calculated 95% confidence intervals according to Wilson's method. Time interval analysis was performed according to the KaplanMeier method. The significance level was determined at p0.05.
Results. A significant decrease in the severity of clinical manifestations according to the World Health Organization Clinical Progression Scale was noted by patients by day 4 after regdanvimab administration. All 92 patients in the cohort were discharged from the hospital l on average on day 5 after regdanvimab administration and on day 9 of the disease. On day 4 after drug administration 82% of patients was being PCR negative. No adverse events related to the administration of regdanvimab were reported during the study.
Conclusion. In real clinical practice, the efficacy and safety of regdanvimab in patients at high risk of severe COVID-19 was confirmed once again, with a positive clinical result observed in a mixed cohort by the causative agent omicron and delta strain.