BACKGROUND Methotrexate (MTX) combination therapy with biological agents has gained increasing interest. Here, we assessed the efficacy and tolerability of the MTX combination therapy in patients with Crohn's disease (CD).

METHODS We performed a multicenter observational study with 185 patients with CD with MTX and biologics combination therapy; the patients were recruited from three IBD Clinics in Korea. We evaluated the outcomes of the MTX combination therapy and examined the predictive factors of clinical and endoscopic remission.

RESULTS MTX was administered orally to 62.7% of patients; the mean dose was 15.5 mg per week, and the mean treatment duration was 36 months. Of the 169 patients treated with MTX combination therapy for over 6 months, the steroid-free clinical remission rates were 34.3%, 26.0%, 29.8%, and 32.7% at 4, 12, 18, and 24 months, respectively. Previous thiopurine use was a significant negatively associated independent factor (p < 0.001), and a higher dose of MTX (≥ 15 mg/week) was a positively associated independent factor of steroid-free clinical remission (p = 0.035). Ninety-six patients underwent follow-up endoscopy after 28 months, and 36 (37.5%) achieved endoscopic remission. Longer disease duration (p = 0.006), ileocolonic type of Montreal location (p = 0.036), and baseline C-reactive protein (CRP) level of more than 5 mg/L (p = 0.035) were significant negatively associated independent factors and a higher dose of MTX (≥ 15 mg/week) was a positively associated independent factor of endoscopic remission (p = 0.037).

CONCLUSIONS MTX combination therapy with biologics was effective and tolerable in patients with CD.