Shingles, also known as herpes zoster (HZ), is a common and sometimes debilitating disease that disproportionately affects elderly individuals and those who are immunocompromised. Patients with rheumatoid arthritis (RA) have a 1.5–2-fold higher risk of developing HZ compared with healthy adults. Treatment with some disease-modifying anti-rheumatic drugs (DMARDs) has been shown to increase this risk. Tofacitinib has been shown to increase the risk of developing HZ, particularly when it is given in combination with methotrexate or prednisone.
Thus, vaccination is recommended for patients ages 50 years and older, prior to starting treatment with biologic agents or tofacitinib. Two studies in this issue of Arthritis & Rheumatology tackle the topic of live zoster vaccination in patients with rheumatoid arthritis before starting and concomitant with tofacitinib.
The first, “The Safety and Immunogenicity of Live Zoster Vaccination in Patients with Rheumatoid Arthritis Before Starting Tofacitinib,” evaluated the effect of tofacitinib, an oral JAK inhibitor used for the treatment of RA, on the immune response to and safety of live zoster vaccine (LZV).1
In this phase II, 14-week, placebo-controlled trial, patients ages 50 years and older who had active RA and were receiving background methotrexate were given LZV and randomized to receive tofacitinib 5 mg twice daily or placebo two to three weeks postvaccination. The researchers measured humoral responses (the varicella zoster virus [VZV]–specific IgG level as determined by glycoprotein enzyme-linked immunosorbent assay) and cell-mediated responses (VZV-specific T cell enumeration, as determined by enzyme-linked immunospot assay) at baseline and two weeks, six weeks and 14 weeks postvaccination. End points included the geometric mean fold rise (GMFR) in VZV-specific IgG levels (primary end point) and T cells (spot-forming cells/106 peripheral blood mononuclear cells) at six weeks postvaccination.
Results: One hundred twelve patients were randomized to receive tofacitinib (n=55) or placebo (n=57). Six weeks postvaccination, the GMFR in VZV-specific IgG levels was 2.11 in the tofacitinib group and 1.74 in the placebo group, and the VZV-specific T cell GMFR was similar in the tofacitinib group and the placebo group (1.50 and 1.29, respectively). Serious adverse events occurred in three patients in the tofacitinib group (5.5%) and 0 patients (0.0%) in the placebo group. One patient who lacked preexisting VZV immunity developed a disseminated rash on day 16 postvaccination (two days after starting tofacitinib). This resolved after tofacitinib was discontinued and the patient received antiviral treatment.
The second study, “Herpes Zoster and Tofacitinib: Clinical Outcomes and the Risk of Concomitant Therapy,” evaluated whether concomitant treatment with conventional synthetic DMARDs (csDMARDs) or glucocorticoids (GCs) contributes to the increased risk of HZ in RA patients treated with tofacitinib.2