Abstract
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.
Key words: common variable immunodeficiency, COVID-19, mRNA
vaccine, post-vaccination response