The goal of this clinical trial is to learn if methotrexate discontinuation affect on immunogeneity of shingrix in RA patients. The main questions it aims to answer are:

Discontinuation of methotrexate after shingrix immunization increase efficacy of the vaccine in patients with RA ?

Researchers will compare humoral and cell-mediated immunity against herpes zoster in RA patients who are vaccinated by shingrix, and compare these immunity between RA patients with MTX discontinuation and MTX continuation groups.

Participants will:

Vaccinated with shingrix twice. MTX continuation group will keep taking MTX after shingrix vaccination, whereas MTX discontinuation group will stop MTX for 2 weeks after shingrix vaccination.

Visit the clinic at baseline (first shingrix vaccination), 2 months later for 2nd shingrix vaccination, then 3 & 6 months later from baseline to achieve blood sample.

Inclusion Criteria:

• fulfill 2010 ACR/EULAR classification criteria for rheumatoid arthritis
• age over 19 years
• methotrexate user
• agree for vaccination with shingrix

Exclusion Criteria:

• have other form of inflammatory arthritis or autoimmune-mediated disease
• malignancy, current infection, pregnancy

IPD can be shared with reasonable request.