ABSTRACT
Patients with indolent lymphoma undertaking recurrent or continuous B cell suppression are at risk of severe COVID-19. Patients and healthy controls (HC; N = 13) received two doses of BNT162b2: follicular lymphoma (FL; N = 35) who were treatment naïve (TN; N = 11) or received immunochemotherapy (ICT; N = 23) and Waldenström's macroglobulinemia (WM; N = 37) including TN (N = 9), ICT (N = 14), or treated with Bruton's tyrosine kinase inhibitors (BTKi; N = 12). Anti-spike immunoglobulin G (IgG) was determined by a high-sensitivity flow-cytometric assay, in addition to live-virus neutralization. Antigen-specific T cells were identified by coexpression of CD69/CD137 and CD25/CD134 on T cells. A subgroup (N = 29) were assessed for third mRNA vaccine response, including omicron neutralization. One month after second BNT162b2, median anti-spike IgG mean fluorescence intensity (MFI) in FL ICT patients (9977) was 25-fold lower than TN (245 898) and HC (228 255, p = .0002 for both). Anti-spike IgG correlated with lymphocyte count (r = .63; p = .002), and time from treatment (r = .56; p = .007), on univariate analysis, but only with lymphocyte count on multivariate analysis (p = .03). In the WM cohort, median anti-spike IgG MFI in BTKi patients (39 039) was reduced compared to TN (220 645, p = .0008) and HC (p < .0001). Anti-spike IgG correlated with neutralization of the delta variant (r = .62, p < .0001). Median neutralization titer for WM BTKi (0) was lower than HC (40, p < .0001) for early-clade and delta. All cohorts had functional T cell responses. Median anti-spike IgG decreased 4-fold from second to third dose (p = .004). Only 5 of 29 poor initial responders assessed after third vaccination demonstrated seroconversion and improvement in neutralization activity, including to the omicron variant.
ABSTRACT
The Pfizer/BioNtech BNT162b2 is a major vaccine used in the Australian COVID-19 immunisation programme. We report on BNT162b2 safety in the observation period in a dedicated vaccination clinic linked to a quaternary teaching hospital. We performed a retrospective review of medical records for 57 842 vaccinations, and describe the model of care and adverse event rate at the clinic during its first 2 months of operation. A total of 243 adverse events following immunisation (0.42% of total vaccine doses) were recorded in the immediate observation period post-vaccination, which were predominantly immunisation stress-related responses. Of the 110 patients who experienced an adverse event with their first dose of the vaccine, 90% returned for their second dose of the vaccine, with 87% not reporting any further adverse reaction with the subsequent dose. Nineteen (0.03% of total doses) people were reviewed for an allergic reaction, of which 10 (53%) reported a history of prior allergies. A female predominance was present in both total adverse reactions (70%) and allergic vaccine reactions (79%). Only two patients experienced anaphylaxis (0.003% of total doses), in keeping with low rates of adverse reactions to the BNT162b2 vaccine in the current literature. Overall, the present study reinforces the safety of BNT162b2 in the Australian population, describes vaccination completion rates after adverse events and identifies predisposing factors for rare allergic reactions to the vaccine.