2-week dc of MTX and Influenza Vaccination in RA (2 wk MTX)

Rheumatoid arthritis (RA) is a chronic systemic inflammatory disease that affects the joints as the main target of the inflammation. Patients with RA require chronic treatment with disease modifying antirheumatic drugs (DMARDs) including methotrexate (MTX), which constitutes the mainstay of treatment. Underlying immune dysfunction and the additional immune suppression associated with treatment render patients with RA more susceptible to infection. Thus, vaccination of the preventive diseases is crucial and recommended in all patients unless contraindicated.

However, low dose of glucocorticoids, conventional DMARDs and biological DMARDs including tumor necrosis factor inhibitors have been reported to substantially decrease vaccine response (4); MTX has been reported to be associated with a decreased response to seasonal influenza vaccination by up to 15%.

To optimize a vaccine response, vaccination should be administrated before the treatment with immunesuppressive medications is initiated. However, most patients with RA are already on stable dose of MTX at the time of when vaccinations. To improve the vaccine response, a short term discontinuation of MTX could be considered. In a prior study, we discovered that a temporary discontinuation of MTX for 4 weeks during peri-vaccination period tended to be associated with an improved response to vaccination with trivalent influenza vaccination (Figure 1). It remains to be defined whether MTX discontinuation for shorter period increases the vaccination efficacy while minimizing the RA flare rate.