High Immunogenicity of the Pneumococcal Conjugated Vaccine in Immunocompromised Adults With Inflammatory Bowel Disease.

INTRODUCTION

Patients with inflammatory bowel disease (IBD) are predisposed to pneumococcal infections due to their underlying disease and iatrogenic immunosuppression. Vaccination with the 13-valent pneumococcal conjugated vaccine (PCV13) is recommended, but with poor take-up and few data available. We performed an open-label, phase IV, multicenter study to evaluate the safety and immunogenicity of PCV13 in adults with IBD and to analyze the influence of immunomodulating treatments on anti-pneumococcal seroresponses.

METHODS

We enrolled 306 patients with IBD from March 2014 through February 2016, with the following exclusion criteria: current IBD flare, pregnancy, pneumococcal immunization in the previous 5 years, and influenza immunization in the previous 4 weeks. PCV13 was administered intramuscularly. Serotype-specific vaccine responses were evaluated using an opsonophagocytic assay. Adverse events were monitored by diary cards and standardized phone interviews.

RESULTS

The median seroprotection rate increased significantly from 43.9% (95% confidence interval [CI], 42.3-45.5) at inclusion to 90.4% (95% CI, 89.5-91.3%; P < 0.001) after vaccination. Patients receiving anti-tumor necrosis factor agents achieved a slightly lower seroprotection rate (from 44.5% [95% CI, 42.3%-46.8%] to 86.6% [95% CI, 84.9%-88.1%]) than patients treated with other types of immunosuppressive regimens (thiopurine, methotrexate, oral corticosteroids; from 44.7% [95% CI, 41.7%-47.7%] to 93.8% [95% CI, 92.1%-95.2%]) or nonimmunosuppressive treatment (5-aminosalicylate, topical corticosteroids, vedolizumab; from 41.3% [95% CI, 37.9%-44.8%] to 95.2% [95% CI, 93.4%-96.6%]). There were no safety issues.

DISCUSSION: Overall, the administration of PCV13 was highly immunogenic and well tolerated, irrespective of the baseline treatment, and should be encouraged in all adults with IBD.