Second COVID vaccine improves the serological response in patients with autoimmune diseases

A recent study by Simader et al., published in the Annals of Rheumatic Diseases, has concluded that full two-course immunization against SARS-CoV-2 is important to achieve efficient serological responses to vaccination in patients with rheumatoid arthritis (RA) and seronegative spondylarthritis (SpA) undergoing DMARD therapy.

Vaccination has greater significance in reducing the morbidity of infectious diseases in patients receiving immunomodulating therapies. Certain previous studies have reported that vaccine response in immunocompromised patients is a major concern, as the treatment or disease itself can interfere with the vaccine efficiency.

The study involving 53 RA patients, 46 patients with SpA has evaluated the humoral response to mRNA vaccines following 1st and 2nd doses in terms of seroconversion rate and titer.

The researchers found that the seroconversion rates were 100% in all the groups following the second immunization, whereas it was only 54% after the first immunization in patients with inflammatory arthritis. However, there are studies reporting that methotrexate and glucocorticoids may impair the immunogenicity of SARS-CoV-2 vaccines.

Although the European League Against Rheumatism (EULAR) and the American College of Rheumatology (ACR) advocate vaccination in all patients with autoimmune diseases, there is no evidence-based data to formulate vaccination strategies for patients undergoing specific immunomodulatory therapies or those having autoimmune diseases.

The present study highlights the importance of the second dose of the primary vaccine series is to develop a complete serological response in patients with inflammatory arthritis.