Ioanna Zarkada (Greece)
Cystic Fibrosis Department, ‘‘Aghia Sophia” Children’s Hospital, Athens, Greece Cystic Fibrosis Department, ‘‘Aghia Sophia” Children’s Hospital, Athens, GreeceAuthor Of 1 Presentation
IMMUNOGENICITY OF THE BNT162B2 COVID-19 VACCINE IN PEDIATRIC AND YOUNG ADULT PATIENTS WITH CYSTIC FIBROSIS
Abstract
Backgrounds:
Cystic fibrosis (CF) patients constitute a high-risk group for severe COVID-19. We prospectively measured total (TAbs-RBD; U/ml) and neutralizing (NAbs-RBD; %) antibodies of SARS-CoV-2 spike-RBD protein before immunization, 20 days after the 1st and 30 days after the 2nd dose of the BNT162b2 vaccine in CF patients and healthy controls.
Methods
Serum samples were tested using the Elecsys® Anti-SARS-CoV-2 S reagent. Values of ≥0.8 U/ml are positive. The determination of anti-RBD neutralization titers was carried out using the Food and Drug Administration(FDA) approved blocking ELISA cPassTM SARS-CoV-2 neutralization antibody detection kit. Percentages of ≥ 30% were positive. A statistical analysis was performed for the comparison of the two groups and the possible association of antibody levels with epidemiological and clinical parameters.
Results:
A total of 33 patients with CF and 66 healthy controls were included in the study. The median age (IQR) of the CF group was 19.6 (17.6-24.3) years and 18 (54.5%) were females. CF patients had statistically significant higher antibody responses regarding TAbs-RBD and NAbs-RBD after both doses (P-value<0.001). One month after the 2nd dose, CF and controls had TAbs-RBD (IQR): 3396 (2443) and 1452 (1231) U/ml, respectively. Similarly, the NAbs-RBD (%) were: 97.30 (1.00) and 95.70 (3.71) (%), respectively. Among CF patients no statistically significant differences were detected for TAbs-RBD or NAbs-RBD regarding gender, pancreatic status, CFTR genotype of CF, use of CFTR modulators and chronic Pseudomonas Aeruginosa infection.
Conclusions/Learning Points:
The BNT162b2 vaccine was more immunogenic in patients with CF patients compared to healthy controls regardless of the CFTR genotype, related comorbidities, treatment type or severity of disease. Longitudinal studies regarding the kinetics of antibodies will be important to determine the appropriate timing for a booster dose in this population.