Background Biologic agents are highly effective for rheumatoid arthritis (RA); however, not all cases achieve clinical remission. It is difficult to predict the effectiveness before starting the treatment.

Objectives To study predictive factors for clinical remission, which is one of the treatment goals in RA, after using biologic agents for 6 months.

Methods The subjects were 333 RA patients treated with biologic agents. The following patient's characteristics were investigated: age, gender, the type of biologic agents, the number of previous drugs, disease duration, baseline steroid dosage, MTX dosage, serum RF, MMP-3, ACPA, TNF-α, and IL-6. For evaluation we used SDAI for RA disease activity, HAQ for ADL, Short Form (SF)-36 for QOL, and Hamilton Depression Rating Scale (HAM-D) or Self-rating depression scale (SDS) for depression status, respectively. Clinical remission was defined by SDAI3.3 after 6 months of treatment. The subjects were divided into two groups: patients with SDAI3.3 and patients with SDAI >3.3 at 6 months, and a retrospective study was conducted. 101 patients were excluded from the study due to loss to 6-month follow-up, and a total of 232 patients were analyzed.

Results Compared with a group of RA patients without clinical remission (n=167), a group of patients with clinical remission (n=65) had younger age (50.0±15.5 vs. 59.6±14.1, p<0.001), lower steroid dosage (1.9±2.4 mg/day vs. 4.3±3.8, p<0.001), lower serum MMP-3 (151±197 ng/ml vs. 239±244, p<0.05), lower serum TNF-α (28.4±57.7 pg/ml vs. 76.0±193.8, p=0.028), and lower serum IL-6 (12.5±22.8 pg/ml vs. 60.6±180.8, p=0.017) at baseline. In addition, those who achieved remission showed lower SDAI (17.9±11.7 vs. 28.0±13.7, p<0.001), lower HAQ (0.26±0.38 vs. 0.71±0.63, p<0.001), higher SF-36 (p<0.05 in all categories), lower SDS (38.0±9.5 vs. 42.5±9.7, p=0.0061), and lower HAM-D (4.7±3.6 vs. 6.4±5.2, p<0.05) at baseline. On the other hand, there was no significant difference on gender, the types of biologic agents, the order of drugs used in the treatment, MTX dosage, disease duration, serum RF, and ACPA.

Conclusions It was suggested that RA patients with lower disease activity, lower dosage of steroid, younger age, higher ADL and QOL, lower depression scores, and lower serum TNF-α and IL-6 at baseline are more likely to achieve clinical remission with biologic treatment.

Disclosure of Interest Y. Miwa Grant/research support from: Astellas Pharm Inc., Mitsubishi Tanabe Pharma Corporation, AbbVie CK, Pfizer Japan Inc., Chugai Pharmaceutical Co., Ltd., and Eizai Co., Ltd., R. Takahashi: None declared, S. Isojima: None declared, T. Isozaki: None declared, M. Saito: None declared, N. Oguro: None declared, S. Nishimi: None declared, T. Kasama: None declared, K. Oh: None declared, Y. Toyoshima: None declared, K. Inagaki: None declared