A randomized, double-blind, three-arm, placebo/active-controlled, multicenter clinical trial to evaluate the efficacy and safety of Ferrous Maltol Capsules in patients with inflammatory bowel disease complicated by iron deficiency anemia

INTERVENTION: Placebo Group:Placebo;Positive Control Group:Ferric maltol capsules (brand name: Feraccru);Trial Group:Ferric maltol capsules; CONDITION: Inflammatory bowel disease, IBD PRIMARY OUTCOME: Change from baseline in hemoglobin at 12 weeks; SECONDARY OUTCOME: Change from baseline in hemoglobin at 4 and 8 weeks;Proportion of subjects with hemoglobin increase >=10 g/L at week 12;Proportion of subjects with hemoglobin increase >=20 g/L at week 12;Proportion of subjects with hemoglobin within normal range at week 12;Change from baseline in iron metabolism parameters (serum iron, serum ferritin, transferrin saturation) at weeks 4, 8, and 12; INCLUSION CRITERIA: 1. Age 18 years or older (including 18 years), gender not restricted; 2. Current diagnosis of quiescent inflammatory bowel disease (including ulcerative colitis or Crohn's disease) accompanied by iron deficiency anemia, and meeting the following diagnostic criteria: (1) Quiescent ulcerative colitis is defined as a Simple Clinical Colitis Activity Inde X(SCCAI) score <4 points measured at screening. Quiescent Crohn's disease is defined as a Crohn's Disease Activity Inde X(CDAI) score <220 points measured at screening; (2) Anemia is defined as hemoglobin measured at screening: 90 g/L <= females <110 g/L, 90 g/L <= males <120 g/L; (3) Presence of iron deficiency, defined as serum ferritin <30 µg/L measured at screening, or serum ferritin <100 µg/L and transferrin saturation <20%; 3. Patients receiving protocol‐allowed immunosuppressant therapy at screening must have been on a stable dose for at least 4 weeks prior to randomization: (1) Allowed immunos