Clinical outcomes, immunogenicity, and safety of BNT162b22 Vaccine in
Primary Antibody Deficiency
Background: Common variable immunodeficiency (CVID) is
characterized by an impaired post-vaccination response, high
susceptibility to respiratory tract infections, and a broad spectrum of
non-infectious complications. Thus, patients with CVID are at high risk
of coronavirus disease 2019 (COVID-19), and vaccination’s role in
prevention is questionable. The main aim of this study was to evaluate
the clinical outcomes, safety, and dynamics of humoral and T-cell immune
responses induced by the mRNA vaccine BNT162b2 in CVID.
Methods: This prospective observational cohort study focused on
the clinical outcomes (proportion of infected patients, disease
severity), safety (adverse-event incidence, laboratory-parameter
changes), and dynamics of humoral (specific post-vaccination and
virus-neutralizing-antibody assessment) and T-cell immune responses
(anti-SARS-CoV-2 specific T-cell detection) in 21 patients with CVID
after a two-dose administration of BNT162b2. The patients were followed
for 6 months. Results: Humoral response was observed in 52%
(11/21) of patients at month 1 post-vaccination but continuously
decreased to 33.3% (5/15) at month 6. Nevertheless, they had a
remarkably lower anti-SARS-CoV-2 neutralizing antibody titer than
healthy controls. The T-cell response was measurable in 33% (6/17) of
patients with CVID at month 1, and it persisted for the study period.
Mild infection occurred in three patients (14.3%) within the follow-up
period. The vaccine also exhibited a favorable safety profile.
Conclusions: The BNT162b2 vaccine elicited a measurable
antibody response in a high proportion of patients, but it was limited
by low titer of the virus-neutralizing antibodies and rapid waning of
anti-RBD SARS-CoV-2 specific antibodies. T-cell response was detected in
one-third of the patients and remained stable within the follow-up
period. Vaccination has favorable safety and clinical-related outcomes
in preventing severe COVID-19.