Recombinant zoster vaccine immunization rate in patients on Janus kinase inhibitors for rheumatologic and dermatologic conditions.

Objectives: Patients who receive Janus kinase (JAK) inhibitors are at an increased risk of varicella zoster virus reactivation. The primary objective of this study was to evaluate the vaccination rates of recombinant zoster vaccine (RZV) for patients taking a JAK inhibitor for dermatologic or rheumatologic conditions. Methods: A facility-based cross-sectional study design was employed to select patients who were ≥18 years of age and were prescribed a JAK inhibitor for at least 6 months by a rheumatologist or dermatologist for any rheumatologic or dermatologic condition. Data analysis was undertaken using descriptive methods. Results: There were 102 patients included in this study, with most patients being female (77.5%), ≥50 years of age (71.6%), White (77.5%) and with RA (76.5%). The proportion of patients who received at least one RZV (at any time in relation to JAK inhibitor initiation) was 27.5% (28/102). Only three patients received at least one dose of RZV within 30 days before or after initiation of a JAK inhibitor. Conclusion: Many patients receiving JAK inhibitors are not vaccinated with RZV, and of those who are vaccinated, the timing of vaccination rarely coincided with JAK inhibitor initiation and thus did not appear to be the motivation for vaccination. These data will be used to optimize vaccination workflow within ambulatory clinics to mitigate herpes zoster risk in this population.