P986 Effectiveness of the adjuvanted recombinant zoster vaccine (RZV) in preventing herpes zoster (HZ) among patients ≥50 years of age with Inflammatory Bowel Disease in the United States: A retrospective real-world database analysis from 2018 to 2021

Abstract

Abstract Background Patients with inflammatory bowel disease (IBD) are at higher risk of developing HZ compared to general population.1 The US Food and Drug Administration (FDA) approved RZV for adults ≥50 years of age (YOA) in Oct 2017 and for adults ≥18 YOA who are or will be at increased risk of HZ due to immunodeficiency or immunosuppression, as patients with IBD, in Jul 2021. This study addresses an information gap for RZV vaccine effectiveness (VE) in preventing HZ among IBD patients ≥50 YOA. Methods We conducted a retrospective matched cohort study using the Optum Clinformatics Data Mart healthcare administrative claims database from Jan 2018 to Dec 2021. Patients ≥50 YOA with IBD who received 2 RZV doses with dose interval ≥28 days (RZV [2-dose] cohort) were 1:3 matched to their unvaccinated counterparts (non-RZV cohort) by age, medication category, and other confounders (propensity score). The index date for RZV cohort was the date of the second dose and for non-RZV cohort was the same index date as their vaccinated match. Follow-up started from index date +30 days until earliest date of HZ occurrence, end of enrolment, death, receipt of HZ vaccine, or study end. The first HZ episode during follow-up was identified using an algorithm that included ICD-10 diagnosis code, inpatient or outpatient claims and/or HZ antiviral medication used within 7 days pre/post-HZ diagnosis. Incidence rates (IRs) of HZ were calculated overall, stratified by condition (ulcerative colitis [UC], Crohn’s disease [CD]) and age. Cox hazards models were used to estimate overall and stratified hazard ratios (HRs). VE (%) was calculated as (1−HR) × 100. A similar approach was used to evaluate VE for patients who received 1 RZV dose. Results We identified 6501 RZV vaccinated and 19962 matched unvaccinated IBD patients who were included in the 2-dose analysis (Table). The IR of HZ was 2.92/1000 person-years (PY) in the RZV cohort and 10.96/1000 PY in the non-RZV cohort, resulting in a VE of 73.4% (95% confidence intervals [CIs]: 60.8-82.0) for IBD patients (Figure). VE against HZ was 63.5% (95%CIs: 43.0-76.6) and 85.7% (95%CIs: 69.5-93.3) in UC and CD 2-dose cohorts. IRs and VE stratified by condition and age are presented in Figure. Adjusted VE for IBD patients who received 1 RZV dose was 63.4% (95%CIs: 24.9-82.2). Conclusion Our analysis provides real-world evidence that RZV vaccination is effective in preventing HZ in IBD patients ≥50 YOA and reduce the burden in this population with increased risk of HZ. These findings are consistent with the available literature on RZV effectiveness in patients with IBD, suggesting that this population could greatly benefit from RZV vaccination. 1. Yun H et al, Arthritis Rheumatol 2016;68:2328-37 Funding GSK