Objectives Adolescents with juvenile-onset autoimmune inflammatory rheumatic diseases (AIIRD) could be at-risk for disease flare secondary to SARS-CoV-2 infection or to withholding anti-inflammatory therapy. While vaccination can protect against COVID-19, safety and immunogenicity data regarding anti-SARS-CoV-2 vaccines among adolescents with AIIRD are limited. This international, prospective, multicentre study evaluated the safety and immunogenicity of the BNT162b2 anti-SARS-CoV-2 vaccine among adolescents and young adults with juvenile-onset AIIRD, 80% of whom are on chronic immunomodulatory therapy. Methods Vaccine side effects, disease activity, and short-term efficacy were evaluated after 3 months in 91 patients. Anti-spike S1/S2 IgG antibody levels were evaluated in 37 patients and 22 controls, 2–9 weeks after the second dose. Results Ninety-one patients and 40 healthy controls were included. Safety profile was good, with 96.7% (n = 88) of patients reporting mild or no side-effects, and no change in disease activity. However, 3 patients had transient acute symptoms: 2 following the first vaccination (renal failure and pulmonary haemorrhage) and 1 following the second dose (mild lupus flare vs viral infection). Seropositivity rate was 97.3% in the AIIRD group compared with 100% among controls. However, anti-S1/S2 antibody titres were significantly lower in the AIIRD group compared with controls (242 ± 136.4 vs 387.8 ± 57.3 BAU/ml, respectively; p< 0.0001). No cases of COVID-19 were documented during the 3-month follow-up. Conclusion Vaccination of juvenile-onset AIIRD patients demonstrated good short-term safety and efficacy, high seropositivity rate, but lower anti-S1/S2 antibody titres compared with healthy controls. These results should encourage vaccination of adolescents with juvenile-onset AIIRD, even while on immunomodulation.

Objectives Effectiveness of the BNT162b2 mRNA COVID-19 vaccine for adolescents with juvenile-onset inflammatory rheumatic diseases (IRD) is unknown. Several studies suggested attenuated immunogenicity in patients with IRD. This study evaluated the effectiveness of the BNT162b2 mRNA COVID-19 vaccine in preventing COVID-19 infection in adolescents with juvenile-onset IRD compared with controls without immune rheumatic disease. Methods We used data from Clalit Health Services, the largest healthcare organization in Israel, to conduct an observational cohort study from February to December 2021, involving adolescents 12–18 years-old, diagnosed with IRD. Study outcomes included documented COVID-19 infection in relation to vaccination status and immunomodulatory therapy. We estimated vaccine effectiveness as one minus the risk ratio. Adolescents without immune rheumatic disease, 12–18 years-old, served as controls. Results A total of 1,639 adolescents with IRD (juvenile idiopathic arthritis, systemic lupus erythematosus, or familial Mediterranean fever) were included and compared with 524 471 adolescents in the same age range. There was no difference in COVID-19 infection rates after the second dose of vaccine for those with IRD and controls (2.1% vs 2.1% respectively, p= 0.99). The estimated vaccine effectiveness for adolescents with IRD was 76.3% after the first dose, 94.8% after the second and 99.2% after the third dose. Conclusion We found that the BNT162b2 mRNA vaccine is effective against COVID-19 infection in adolescents with IRD, similar to controls without immune rheumatic disease. Immunomodulatory therapy did not affect its effectiveness. These results can encourage adolescents with IRD to get vaccinated against COVID-19.

Background The COVID-19 outbreak has led to the rapid development and administration of the COVID-19 vaccines worldwide. Data about the immunogenicity and adverse effects of the vaccine on patients with systemic autoimmune rheumatic diseases (SARDs) is emerging. Aim To evaluate Pfizer/BioNTech (BNT162b2) mRNA-based vaccine second-dose immunogenicity and safety, and the relation between them, in patients with SARDs. Methods A total of one hundred forty tow adults who received two doses of the BNT162b2 vaccine were included in the study. The SARDs group included Ninety-nine patients and the control group (forty-three participants) comprised a mixture of healthy participants and patients who were seen at the rheumatology clinic for non-SARDs. Anti-SARS-CoV-2 IgG antibodies against the Spike protein were evaluated using a SARS-CoV-2 IgG immunoassay. A level of > 150 AU/mL was considered positive. An adverse effects questionnaire was given to the participants upon their first visit to the clinic after their BNT162b2 vaccination. Results Of the 142 participants, 116 were seropositive (81.7%) and 26 (18.3%) were seronegative. Of the seronegative participants, 96.2% were SARDs patients. The proportion of seropositivity in the SARDs patients treated with any immunosuppressant was significantly lower (69.9%) compared to the control group and SARDs patients not receiving immunosuppressants (96.8%). A significant negative correlation between seronegativity and treatment with rituximab, mycophenolate mofetil (MMF), and prednisone was found in the SARDs group (p = 0.004, 0.044, 0.007 respectively). No fever was observed following the BNT162b2 vaccine in seronegative patients, and the frequency of musculoskeletal adverse effects upon the second dose of the BNT162b2 vaccine was significantly higher in seropositive compared to seronegative patients and in the control group compared to the SARDs patients (p = 0.045, p = 0.02 respectively). Conclusion A decline in the immunogenicity to the second dose of BNT162b2 mRNA is seen in patients with SARDs, especially in patients treated with rituximab, MMF, and prednisone. Adverse effects of the vaccine including fever and musculoskeletal symptoms might be a signal for the acquisition of immunity in those patients. Key Points• BNT162b2 mRNA vaccine is less immunogenic in SARDs patients compared to the control group.• Rituximab, prednisone, and mycophenolate mofetil significantly reduced immunogenicity to the vaccine.• There is a correlation between immunogenicity and adverse effects of the vaccine.