Humoral and T Cell Response to SARS-CoV-2 Vaccination in Patients With Rheumatoid Arthritis.

OBJECTIVE: The objective of this study was to assess the SARS-CoV-2-specific humoral and T cell response after a two-dose regimen of SARS-CoV-2 vaccine in patients with rheumatoid arthritis (RA). METHODS: In this observational study, patients with RA who are ≥18 years of age and vaccinated for SARS-CoV-2 according to the Argentine National Health Ministry's vaccination strategy were included. Anti-SARS-CoV-2 immunoglobulin G (IgG) antibodies (ELISA-COVIDAR test), neutralizing activity (cytotoxicity in VERO cells), and specific T cell response (IFN-γ ELISpot Assay) were assessed after the first and second dose. RESULTS: A total of 120 patients with RA were included. Mostly, homologous regimens were used, including Gam-COVID-Vac (27.5%), ChAdOx1 (24.2%), and BBIBP-CorV (22.5%). The most frequent combination was Gam-COVID-Vac/mRNA-1273 (21.7%). After the second dose, 81.7% presented with anti-SARS-CoV-2 antibodies, 70.0% presented with neutralizing activity, and 65.3% presented with specific T cell response. The use of BBIBP-CorV and treatment with abatacept (ABA) and rituximab (RTX) were associated with undetectable antibodies and no neutralizing activity after two doses. BBIBP-CorV was also associated with the absence of T cell response. The total incidence of adverse events was 357.1 events per 1,000 doses, significantly lower with BBIBP-CorV (166.7 events per 1,000 doses, P < 0.02). CONCLUSION: In this RA cohort vaccinated with homologous and heterologous regimens against COVID-19, 2 out of 10 patients did not develop anti-SARS-CoV-2 IgG, 70% presented with neutralizing activity, and 65% presented with specific T cell response. The use of BBIBP-CorV was associated with deficient humoral and cellular response, whereas treatment with ABA and RTX resulted in an impaired anti-SARS-CoV-2 IgG formation and neutralizing activity.

Immune Response to SARS-CoV-2 Third Vaccine in Patients With Rheumatoid Arthritis Who Had No Seroconversion After Primary 2-Dose Regimen With Inactivated or Vector-Based Vaccines.

OBJECTIVE: The aim of this study was to assess the immune response after a third dose of SARS-CoV-2 vaccine in patients with rheumatoid arthritis (RA) with undetectable antibody titers after the primary regimen of 2 doses. METHODS: Patients with RA with no seroconversion after 2 doses of SARS-CoV-2 vaccine and who received a third dose of either an mRNA or vector-based vaccine were included. Anti-SARS-CoV-2 IgG antibodies, neutralizing activity, and T cell responses were assessed after the third dose. RESULTS: A total of 21 nonresponder patients were included. At the time of vaccination, 29% were receiving glucocorticoids and 85% biologic disease-modifying antirheumatic drugs (including 6 taking abatacept [ABA] and 4 taking rituximab [RTX]). The majority (95%) received the BNT162b2 vaccine and only one of them received the ChAdOx1 nCoV-19 vaccine. After the third dose, 91% of the patients presented detectable anti-SARS-CoV-2 IgG and 76% showed neutralizing activity. Compared to other treatments, ABA and RTX were associated with the absence of neutralizing activity in 4 out of 5 (80%) patients and lower titers of neutralizing antibodies (median 3, IQR 0-20 vs 8, IQR 4-128; P = 0.20). Specific T cell response was detected in 41% of all patients after the second dose, increasing to 71% after the third dose. The use of ABA was associated with a lower frequency of T cell response (33% vs 87%, P = 0.03). CONCLUSION: In this RA cohort, 91% of patients who failed to seroconvert after 2 doses of SARS-CoV-2 vaccine presented detectable anti-SARS-CoV-2 IgG after a third dose. The use of ABA was associated with a lower frequency of specific T cell response.