Study identifies risk factors for impaired BNT162b2 mRNA antibody response in lupus

Among systemic lupus erythematosus (SLE) patients, SARS-CoV-2-specific immune responses after BNT162b2 vaccination seem to be impaired in the presence of poor baseline humoral immune status, low naïve B cell frequencies, and mycophenolate mofetil (MMF) and methotrexate (MTX) use, according to a study.

The study included 126 SLE patients. All of them had their disease activity and clinical assessments recorded starting on the day the patients received their first dose of the BNT162b2 vaccine until day 15, on which the patients received their second dose.

Researchers measured SARS-CoV-2 antibody responses against wild-type spike antigen, while they evaluated serum-neutralising activity against the SARS-CoV-2 historical strain and variants of concerns (VOCs). They also quantified vaccine-specific T cell responses following the second dose using the interferon-γ release assay.

The BNT162b2 vaccine was well tolerated by the patients. Throughout the study, BILAG (British Isles Lupus Assessment Group) and SLEDAI (SLE Disease Activity Index) scores were similar in patients with active and inactive disease at baseline.

BNT162b2 antibody response was drastically reduced among patients on MMF (p=0.007) and those on MTX (p<0.001). Antispike antibody response showed a positive association with baseline total immunoglobulin G serum levels (p=0.018), naïve B cell frequencies (p=0.003), and SARS-CoV-2-specific T cell response (p=0.003).

Among responders, serum neutralisation activity decreased against VOCs that harboured the E484K mutation, although it remained detectable in most patients.

The present data pinpoint SLE patients who might need adapted vaccine regimens and follow-up.