Even though a single high dose administration of intravenous ferric carboxymaltose (FC) is supposed to be effective, it is unknown whether the second dose of FC given one week after the initial dose provides additional benefits. The aim of the present study was to investigate whether two doses of intravenous ferric carboxymaltose is more effective than a single dose of intravenous FC for replenishing iron stores and correction of anemia in patients with iron deficiency.
This retrospective study was performed on medical records of a total of 516 patients treated with FC in the hematology department of a tertiary care center between 2016 and 2018. Patients were allocated into two groups: Group I (n = 367) had received a single dose (1000 mg) of FC, while Group II (n = 149) had two doses of 1000 mg of FC repeated with a one-week interval. Etiologies of anemia, baseline descriptives as well as hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), ferritin and transferrin saturation (TS) before and after treatment were compared between 2 groups.
The increases in levels of Hb (p < 0.001), Hct (p < 0.001), MCV (p < 0.001), ferritin (p = 0.012) and TS (p = 0.007) after intravenous FC treatment were more effective in Group II. Pre-treatment levels of Hb, Hct, MCV, and ferritin significantly influence the response to FC treatment, whereas TS values before treatment do not have a remarkable impact on therapeutic response. The second dose of FC was quite useful to fulfill the iron stores and achieve Hb, Hct and ferritin levels four weeks after treatment.
Our results demonstrated that two doses of intravenous FC provide a more rapid and more effective treatment regimen for iron deficiency anemia compared to a single dose.