The use of combination biological or small molecule therapy in inflammatory bowel disease: A retrospective cohort study

Objective: There are limited data on using more than one biologic or small molecule drug combined to treat patients with inflammatory bowel disease. The aim of our study was to determine the effectiveness and safety of combination biologic use in inflammatory bowel disease. Methods: We identified patients with Crohn's disease or ulcerative colitis who received treatment with a combination of two biologics or a biologic and a small molecule drug from 2015 to 2019 for persistent disease activity or concomitant rheumatological or dermatological disease. The primary end-point was effectiveness, based on improvements in inflammatory markers, clinical, and endoscopic remission. The secondary end-point was safety. Results: Of the 50 patients treated with combination therapy there were significantly more patients in clinical and endoscopic remission at follow-up compared to baseline (50% vs 14%, P = 0.0018, delta 36%, 95% confidence interval [CI] 0.13-0.53; and 34% vs 6%, P = 0.0039, delta 28%, 95% CI 0.09-0.47), respectively. Median erythrocyte sedimentation rate (17 mm/h vs 13 mm/h, P = 0.002) and C-reactive protein (5.00 mg/dL vs 2.35 mg/dL, P = 0.002) also decreased posttreatment. There were eight serious adverse events and no deaths. Conclusions: Combination biologic therapy appears to be an effective option for patients with refractory inflammatory bowel disease or concomitant autoimmune disease that is inadequately controlled by biologic monotherapy. There was an increased risk of serious infection compared with biologic monotherapy; however, this risk might be minimized by discontinuing immunomodulators prior to initiating combination therapy. Large prospective studies are needed to confirm these findings.