Can rituximab be used in the treatment of pemphigus vulgaris during the COVID-19 pandemic?

Rituximab is a monoclonal antibody that targets CD20, a B-lymphocyte antigen; that leads to a decline in the B-cell counts for at least a year. The patients who have received rituximab treatment in the previous 5 years with the diagnosis of pemphigus group of diseases at Cerrahpaşa Medical Faculty were questioned for COVID-19 infection. A total of 48 patients were included in this study; only one male patient had COVID-19 infection which had a mild course. There is no significant difference in the total number of lymphocytes between patients who have received rituximab within the previous 5 years or last year. The number of lymphocytes is independent of the number of courses of rituximab treatment received. Therefore, we suggest that all pemphigus patients who have received rituximab treatment within the previous 5 years should be careful of the preventive measures against the COVID-19 infection irrespective of the number of treatment courses or the number of years which has passed since the treatment. The disease course was mild in the only infected patient. Thus, rituximab may be used in the treatment of pemphigus vulgaris during the COVID-19 pandemic if its use is necessary.