Objective: To study the impact of disease and treatment with DMARDs on antibody response elicited by either pneumococcal conjugate vaccine (PCV13) or pneumococcal polysaccharide vaccine (PPV23) in patients with SSc.
Methods: Forty-four SSc patients and 49 controls received a dose of either PCV13 or PPV23. Twelve patients were treated with DMARDs. Antibody levels to pneumococcal polysaccharides 6B and 23 F were measured before and 4-6 weeks after vaccination using ELISA. Antibody functionality was studied using opsonophagocytic assay performed on serotype 23 F.
Results: Number of patients, percentage female and mean age (years) at vaccination were: 32, 94%, 57.5 years in SSc without DMARDs; 12, 100%, 55.5 years in SSc on DMARDs and 49, 63% and 50.6 years in controls. Post-vaccination antibody levels for both serotypes increased significantly in SSc without DMARDs and controls (P < 0.001), but in SSc on DMARDs only for 6B (P = 0.041). Compared with the other groups, patients with SSc receiving DMARDs had lower post-vaccination antibody levels for both serotypes. Opsonophagocytic assay increased significantly in all three groups. No significant difference in immunogenicity between PCV13 and PPV23 was seen.
Conclusion: Pneumococcal vaccination using either PCV13 or PPV23 yielded satisfactory antibody response in SSc patients without DMARD treatment, but a lower response in patients treated with synthetic DMARDs. Type of pneumococcal vaccine (conjugate or polysaccharide) did not significantly influence antibody response.
Trial registration: ClinicalTrials.gov, http://clinicaltrials.gov, NCT02240888.