OBJECTIVES: Anemia is a common condition in Japan. In addition to orally administered iron preparations, the intravenous iron preparations, saccharated ferric oxide (SFO) or ferric carboxymaltose (FCM), can be prescribed in Japan. The objective of the study was to investigate patients’ iron need compared to the actual total dose infused with SFO and FCM.

METHODS: A health insurance claims database with annual check-ups provided by DeSC Healthcare, Inc. (Tokyo, Japan) was used. The patients who had at least one SFO/FCM infusion were selected. The distributions of patients by number of infusions were calculated. An episode was identified by the wash-out periods of 28 days before the first and after the last infusion. The index date was the first infusion date of each episode. The iron need was estimated using hemoglobin and body weight with the formula in the package insert and was compared with actual total dose infused.

RESULTS: The dataset contained 1,227,909 infusions of SFO (of 83,712 patients) and 1,052 of FCM (of 559 patients). The average numbers of infusions of SFO/FCM were 14.7 and 1.9, respectively. The proportions of the patients having just one infusion was 11.5% for SFO and 47% for FCM. We found 62,754 SFO and 399 FCM episodes and the mean (standard deviation) of the total dose were 422mg (502 mg) and 910mg (445mg) respectively. Among them, 588 SFO and 11 FCM episodes had hemoglobin and weight information within 30 days before the index. Of these, 580 (98.6%) for SFO and 4 (36.4%) for FCM had actual infused amounts less than the estimated iron need.

CONCLUSIONS: In many Japanese patients, currently available intravenous iron drugs seem to be infused in low dose, potentially because a large proportion of patients receive only one infusion out of the total number needed suggested by the package inserts.