3rd Vaccine Dose May Benefit ANCA-Associated Vasculitis Patients Save

ARD has publish a prospective, multicenter, observational study of vaccination outcomes in antineutrophil cytoplasmic antibodies associated vasculitis (AAV) patients, showing that AAV patients may not be adequately protected after standard two-dose COVID-19 vaccination, but that a third vaccine dose of BNT162b2 induced a strong neutralising antibody activity against B.1.617.2 in most individuals. Unfortunately, patients receiving rituximab showed no humoral vaccine response even after a third vaccine dose.

Humoral and cellular immune responses to standard two-dose COVID-19 vaccinations are oftent in immunosuppressed patients with AAV. This is of particular concern with the emerging delta variant (B.1.617.2) with greater severity and higher transmissibility.

Researchers looked for humoral responses to B.1.617.2 after a third vaccine dose with BNT162b2 in 21 patients with AAV on immunosuppressive maintenance therapy.

Humoral responses (antispike S1 IgG and surrogate neutralising antibodies) were assayed 23 (21–58) days after standard two-dose COVID-19 vaccination, before a third vaccine dose, and again 21 (21–21) days after third vaccination (booster).

After second COVID-19 vaccine dose, Seroconversion was seen, albeit at a lower rate compaired to healthy individuals. The use of a third, booster, vaccine dose with BNT162b2 resulted in a significant increase in neutralising antibody activity against B.1.617.2.

AAV patients receiving rituximab maintenance therapy had significantly lower anti-S1 IgG, surrogate neutralising and B.1.617.2 neutralising antibody levels after third vaccination compared with patients not receiving rituximab treatment.  Nearly all (12/13) patients without rituximab treatment showed neutralising activity against B.1.617.2, whereas none of those treated with rituximab showed neutralising activity after a third vaccine dose.

These data indicate show detectable antibody levels after standard two-dose vaccination, but at significantly lower levels compared with healthy individuals.

Those receiving rituximab had very low seroconversion rates without detectable neutralising antibody activity against B.1.617.2.

While booster (third) doses may be effective and necessary in AAV patients, receipt of RTX currently or in the last year was associated with no humoral vaccine response even after a third vaccine dose.