A randomized controlled trial of thrice-weekly versus thrice-daily oral ferrous fumarate treatment in adult patients with iron-deficiency anemia

Iron deficiency anemia (IDA) is a common health problem in developing countries. Many studies have shown that low-dose oral iron could have similar efficacy and less gastrointestinal effects in iron deficiency without anemia. This prospective open-labeled randomized controlled study was designed to compare the response of 200 mg ferrous fumarate thrice-weekly (TIW) as not inferior to the thrice-daily (TID) regimen and to assess the incidence of adverse events (AEs) between two regimens in treating adult patients with IDA. The primary endpoint was either an increase in Hb ≥ 3 g/dL, having Hb of 12 g/dL in females or 13 g/dL in males at the 12th week of treatment. Secondary outcomes included adverse events (AEs), red blood cell indices, iron profiles, and patient compliance. Sixty-four patients were randomized: 32 in the TIW arm and the other 32 in the TID arm. The response rates were not different between two arms either with intention to treat analysis (72.0%, 95%CI 56.6–88.5 vs. 71.9%, 95%CI 53.3–86.3, p = 0.777); or per-protocol analysis (88.9%, 95%CI 70.8–97.6 vs. 88.5%, 95%CI 69.8–97.6, p = 1.0), respectively. The trial demonstrated non-inferiority at a margin of 23%. Although the iron profile response of the TID arm was earlier than the TIW arm, almost all patients recovered from anemic symptoms at week 4, and hematologic responses were not different at week 12. There were more gastrointestinal AEs in the TID arm. In conclusion, this study showed that the TIW was non-inferior to the TID iron treatment of IDA patients but less AEs and costs.