Anti-SSA antibody positivity could be predictive of treatment response in RA patients

According to a recent retrospective multicenter study, published in the PLOS ONE journal, positive anti-SSA antibodies might be a predictor of insufficient responses to treat-to-target strategy in RA. The study also noted that residual pain may lead to reduced clinical response to methotrexate in RA patients with anti-SSA antibody-positivity.

The study led by Waki and co-workers from Japan involved 210 consecutive RA patients initiated with methotrexate. The influence of anti-SSA antibody positivity on low disease activity (LDA) based on the 28-joint Disease Activity Score and C-reactive protein after 6 months of drug administration were evaluated using a logistic regression analysis. The researchers noted that the rate of achieving LDA was significantly lower in the anti-SSA antibody-positive subjects than in the anti-SSA antibody-negative group (56.2% vs. 75.8%, P = 0.030). However, follow-up after 6 months showed that anti-SSA antibody-positive subjects had significantly higher scores on the visual analog scale (P = 0.038) and were frequently prescribed with nonsteroidal anti-inflammatory drugs (P = 0.018).

Similar to the current findings, a 2021 study by Endo et al. has reported that anti-Ro/SSA antibody positivity helps in predicting poor response to abatacept in RA patients. Anti-Ro/SSA antibody-negative patients demonstrated substantial reduction in both DAS28-ESR and DAS28-C-reactive protein at 12 months than their counterparts (P = 0.02 and 0.04, respectively).

Literature studies have shown that, despite the wider adoption of treat-to-target approach, several patients fail to attain LDA. Anti-cyclic citrullinated protein antibodies, rheumatoid factor, and bone structural damage have been reported as prognostic indicators of treatment response. The present study is touted as the first of its kind evaluating the response to methotrexate in patients naïve to the drugs with or without anti-SSA antibodies.



1. Waki D, Tamai H, Yokochi R, et al. Effects of anti-SSA antibodies on the response to methotrexate in rheumatoid arthritis: A retrospective multicenter observational study. PLoS One. 2022;17(7):e0271921.

2. Endo Y, Koga T, Kawashiri SY, et al. Significance of anti-Ro/SSA antibodies in the response and retention of abatacept in patients with rheumatoid arthritis: a multicentre cohort study. Scand J Rheumatol. 2021;50(1):15-19.