Study of Response to Zoster Vaccine in Adults with Inflammatory Bowel Disease Treated with Medications

Study Visits: * Visit 1 (V1) - day 1 - blood draw, RZV dose 1 * Follow up (FU) 1 - between days 7-15 * FU 2 - between days 22-29 * Visit 2 (V2) - between days 30-90 - RZV dose 2 * FU 3 - V2 + 7-14 days * Visit 3 (V3) - V2 + 21-50 days - blood draw * Visit 4 (V4) - V2 + approximately 360 days - blood draw Primary Objective: • To demonstrate a 10% higher humoral immunogenicity following two doses of RZV in patients on non-TNF biologic therapy compared to those on anti-TNF biologic therapy. Secondary Objectives: * To evaluate the vaccine response rate (VRR) for anti-glycoprotein E (gE) humoral immune responses in patients on non-TNF biologic therapy compared to those on anti-TNF biologic therapy. * To characterize the anti-gE humoral immunogenicity at visit 1 (V1), visit 3 (V3), and visit 4 (V4) in patients on non-TNF biologic therapy compared to those on anti-TNF biologic therapy. * To evaluate the safety and reactogenicity following administration of RZV, up to 30 days post-last vaccination and during the entire post-vaccination follow-up period. * To evaluate IBD activity following administration of RZV, up to 30 days post-last vaccination and during the entire post-vaccination follow-up period. Tertiary/Exploratory Objectives: * To characterize gE-specific CD4+ T-cell mediated immune responses in patients on non-TNF biologic therapy compared to those on anti-TNF biologic therapy. * To characterize gE-specific CD4+ T-cell mediated immune responses in patients on JAKs. * To evaluate the VRR for anti-gE humoral immune responses in patients on Janus Kinase inhibitors (JAKs). * To characterize the anti-gE humoral immunogenicity at V1, V3, and V4 in patients on JAKs. * To determine the relationship between gut microbiota and response to RZV series.