Arthritis patients taking methotrexate have a reduced antibody response compared with those taking other treatments, a study finds.
Arthritis patients who take methotrexate have a reduced antibody response to pneumococcal vaccine compared with those taking TNF blockers or other treatments, according to a study published online earlier this month in Arthritis & Rheumatism.
In the study, 505 patients with rheumatoid arthritis (RA) or spondylarthropathy (SpA) were divided up into six groups: RA patients on MTX; RA patients on anti-TNF plus MTX; RA patients on anti-TNF alone; SpA patients on anti-TNF and MTX; SpA on anti-TNF alone; and SpA patients on NSAIDs or analgesics. (The final group served as a control.)
All of the participants received the pneumococcal vaccine and had their antibody levels measured at the time of vaccination and again four to six weeks later. The results found that the ratio between post- and pre-vaccination antibody levels differed significantly among the groups. Those in the control group had a significantly better ratio than those who were taking MTX or MTX and anti-TNF. Those taking anti-TNF had a lower ratio than those in the control group, though not significantly so.
Methotrexate but not TNF-blockers reduces antibody response following pneumococcal vaccination using 7-valent conjugate pneumococcal vaccine in adult patients with established arthritis (abstract) [Arthritis & Rheumatism]