Haroldas Jonas Bikelis1, Julija Mironova1,2 Irena Butrimienė2,3,
1Vilnius University, Faculty of Medicine, Vilnius, Lithuania
2Vilnius University Hospital Santaros Clinics, Centre of Rheumatology, Vilnius, Lithuania
3Vilnius University, Faculty of Medicine, Institute of Clinical Medicine, Clinic of Rheumatology, Orthopaedics Traumatology and Reconstructive Surgery, Vilnius, Lithuania
Background. Rituximab is one of treatment options for patients with rheumatoid arthritis. It binds to CD20+ B cells and causes their depletion. Therefore, humoral immune response is dampened and COVID-19 vaccination strategy for such patients becomes complicated.
Aim: to present clinical cases of patients with rheumatoid arthritis treated with rituximab and to review literature on the peculiarities of COVID-19 vaccination in such patients.
Methods. A retrospective analysis of 5 clinical cases was performed to evaluate the peculiarities of COVID-19 vaccination in rituximab treated patients with rheumatoid arthritis. Patients written consents to use their medical data for scientific purposes were obtained.
Case series. We present 5 clinical cases of patients with rheumatoid arthritis treated with rituximab in Vilnius University Hospital Santaros Clinics, Centre of Rheumatology during COVID-19 pandemic. Death due to COVID-19 of one patient was recorded. 2 of 4 patients had immune response to COVID-19 vaccine with normal repopulation of B lymphocytes. Remaining 2 patients did not exhibit immune response and did not have repopulated B cells.
Conclusion. The patient data confirm, that rituximab treatment has been associated with a higher risk of worse COVID-19 course, complications and death. Therefore, such patients should be monitored according to the latest guidelines. Due to blunted humoral immune response to the vaccine in patients treated with rituximab and the variable B-cell repopulation timeframe it is advised to aim for individual COVID-19 vaccination strategy.
Keywords: rituximab, COVID-19 vaccine, CD20+ B lymphocytes, humoral immune response, rheumatoid arthritis.