Methotrexate Hampers Immunogenicity to BNT162b2 mRNA COVID-19 Vaccine in Immune-Mediated Inflammatory Disease.

What is already known about this subject?: The impact of COVID-19 has been felt across the globe and new hope has arisen with the approval of mRNA vaccines against the SARS-CoV-2. Studies have shown immunogenicity and efficacy rates of over 90% in the immunocompetent adult population. However, there is a lack of knowledge surrounding the response of patients with immune-mediated inflammatory diseases (IMIDs) who may also be on immunomodulatory medications.Patients with IMID have been shown to have attenuated immune responses to seasonal influenza vaccination.What does this study add?: This study looks at the humoral and cellular immune response to two doses of BNT162b2 mRNA COVID-19 Vaccine in participants with IMID (on immunomodulators) compared with healthy controls.Individuals with IMID on methotrexate demonstrate up to a 62% reduced rate of adequate immunogenicity to the BNT162b2 mRNA vaccination. Those on anti-cytokine or non-methotrexate oral medications demonstrate similar levels of immunogenicity as healthy controls (greater than 90%).Similarly, vaccination did not induce an activated CD8+ T cell response in participants on background methotrexate, unlike healthy controls and patients with IMID not receiving methotrexate.How might this impact of clinical practice or future developments?: These results suggest that patients on methotrexate may need alternate vaccination strategies such as additional doses of vaccine, dose modification of methotrexate, or even a temporary discontinuation of this drug. Further studies will be required to explore the effect of these approaches on mRNA vaccine immunogenicity.