Background/Purpose: Systemic Sclerosis (SSc) is a rare connective tissue disease with multi-systemic involvement, which at times requires the use of immunosuppressive medication. None of the currently approved vaccines for COVID-19 have been tested for efficacy in Immunocompromised individuals. As no data were available on the potential blunting of the immune response against the vaccine caused by immunosuppressant administration, neither on the potential effects of the vaccines on disease activity or progression, we set out to measure serum markers of disease activity and the immune response of the first dose of Oxford/AstraZeneca and Pfizer vaccine in patients with Systemic Sclerosis with or without immunosuppression.

Methods: Forty patients with SSc from our observational study were invited to participate in this study. At the time of abstract submission full data were available for twenty-two patients. Sera samples were tested before and 4 weeks after (+ 7 days) the patients’ first Covid vaccine using two Luminex xMAP based assays. The first (LABScreen COVID plus [CE-IVD]) that measures levels of IgG against SARS-CoV-2 spike protein subunits S1 and S2, the spike receptor-binding domain, and nucleocapsid protein [NP]. The second, a custom made multiplex assay to measure the concentration of 6 chemokines (ccl2, ccl8, ccl19, cxcl9, cxcl10, cxcl11) to determine the IFN score, as previously described (Carriero A et al 2019). Patients with known COVID-19 infection were not invited to take part in the study.

Results: Seven patients were found to have evidence of antibodies on the sample prior to vaccination and excluded from seroconversion analysis. None of the patients reported any serious adverse reaction to the vaccine, or any immediate complications, including the ones with previous signs of infection. 88% of patients on immunosuppression (Mycophenalate Mofetil [MMF] or Methotrexate [MTX]) showed no seroconversion, whereas all patients on either Hydroxychloroquine or no immunosuppression seroconverted after the first dose. None of the participants had a positive result for NP in the second sample, testifying no actual infection within the duration of the study. Regardless of immunosuppression, none of the twenty-two patients showed a significant change of serum IFN score at 4 weeks following vaccination.

Conclusion: Within the limitations of our small sample size, our data has shown that there is a clear reduction in the Covid-19 vaccines ability to produce antibodies in patients on standard immunosuppression such as MMF or MTX. On the other hand, the vaccination was safe and did not cause an increase in the serum IFN score of the patients, nor any immediate complication, regardless of their immunosuppressive treatments. The study is currently analysing the response rate to the second dose. If results are confirmed, a booster third dose preceded by suspension of immunosuppressive therapy should be considered in this patient cohort.

« Back to ACR Convergence 2021

ACR Meeting Abstracts - https://acrabstracts.org/abstract/immunogenicity-of-a-single-dose-of-covid-19-vaccination-in-patients-with-systemic-sclerosis-with-or-without-immunosupression/