Indicators of suboptimal response to anti-tumor necrosis factor therapy in patients from China with inflammatory bowel disease: results from the EXPLORE study

BACKGROUND: Prevalence of inflammatory bowel disease (IBD) is increasing in China. The EXPLORE study evaluated the incidence and indicators of suboptimal responses to first-line anti-tumor necrosis factor (TNF) in patients with ulcerative colitis (UC) or Crohn’s disease (CD). We present results for the mainland China subgroup. METHODS: A retrospective chart review was performed in adults with IBD at 10 centers in mainland China who initiated anti-TNF therapy between 01 March 2010 and 01 March 2015. The cumulative incidence of suboptimal response to first-line anti-TNF therapy was assessed over 24 months using the Kaplan–Meier method. Indicators of suboptimal response were: dose escalation, discontinuation, augmentation with non-biologic therapy, or IBD-related surgery/hospitalization. At site initiation, a survey was conducted with participating physicians to identify barriers to anti-TNF use. RESULTS: Of 287 patients (72% male) examined, 16/35 (45.7%) with UC and 123/252 (48.8%) with CD experienced a suboptimal response to first-line anti-TNF therapy at any point during the observation period (median 27.6 and 40.0 months, respectively). At 1 and 2 years post anti-TNF initiation, the cumulative incidence of suboptimal response was 51.4% and 75.7% for UC and 45.4% and 57.0% for CD, respectively. Median time to first suboptimal response was 7.2 months for UC and 14.3 months for CD. The most frequent indicator of suboptimal response was discontinuation of anti-TNF therapy (9/16, 56.3%) for UC and IBD-related hospitalization for CD (69/123, 56.1%) followed by augmentation with non-biologic therapy for both cohorts (5/16, 31.3% for UC and 28/123, 22.8% for CD). Dose escalation was the least frequent indicator of suboptimal response to anti-TNF therapy (CD: 4/123, 3.3%; UC: not cited as an indicator). The cumulative incidence of suboptimal response within 4 months of first-line anti-TNF therapy (primary non-response) was over 30% in both cohorts. Financial reasons and reimbursement were identified by surveyed physicians as the most common barriers to prescribing an anti-TNF therapy. CONCLUSIONS: Over one-half of patients with IBD are at risk of experiencing a suboptimal response to first-line anti-TNF therapy at 2 years post-initiation in China. This study highlights a substantial unmet need associated with anti-TNF therapies in China. (Clinicaltrials.gov identifier: NCT03090139). SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12876-021-02074-z.