Randomized Open-Label Phase 1 Study of the Pharmacokinetics of Ferric Maltol in Inflammatory Bowel Disease Patients with Iron Deficiency

Background Iron deficiency anemia (IDA) is a common complication of inflammatory bowel disease (IBD). Oral ferric maltol improves and normalizes hemoglobin (Hb) in patients with IBD. Aim This open-label, randomized Phase 1 study evaluated the pharmacokinetics of ferric maltol and its effect on iron indices in IBD patients with iron deficiency (with or without anemia). Methods Iron deficient adult IBD patients received ferric maltol 30, 60, or 90 mg twice daily during an 8-day period. Pharmacokinetics and iron uptake were assessed on days 1 and 8. Results Twenty-four patients were included: 13 with Crohn’s disease and 11 with ulcerative colitis (mean age 39 years; 67 % female, mean Hb 13.0 g/dL; mean reticulocyte Hb content (CHr) 31.9 pg; mean ferritin 13.9 µg/L). Plasma maltol and maltol glucuronide increased rapidly at all doses, reaching maximum plasma concentration ( C max ) 1.0–1.5 h post-dose and declining to baseline after 3–6 h. Maltol and maltol glucuronide exposure (area under the concentration–time curve; AUC) appeared dose proportional with twice-daily dosing, with higher exposure to maltol glucuronide vs. maltol. Mean day 8/day 1 ratios for C max and AUC 0–t indicated no accumulation after 7 days of twice-daily dosing. Serum iron and transferrin saturation (TSAT) increased with all doses (maximum values at 1.5–3.0 h post-dose). Serum ferritin and CHr increased by day 8, with greater improvements with 60 and 90 mg twice-daily doses than with 30 mg twice-daily doses. Conclusions The key constituents of ferric maltol showed predictable pharmacokinetics, with no accumulation over 7 days and increased iron uptake and storage over time at 30–90 mg twice-daily doses.