| "Ideal chelator" | Deferoxamine | Deferiprone | Deferasirox |
---|---|---|---|---|
Route of administration | Oral | Parenteral, usually subcutaneous or intravenous | Oral | Oral |
Plasma half-life | Long enough to give constant protection from labile plasma iron | Short (minutes); requires constant delivery | Moderate (< 2 hours). Requires at least 3-times-per-day dosing | Long, 8–16 hours; remains in plasma at 24 h |
Therapeutic index | High | High at moderate doses in iron-overloaded subjects | Idiosyncratic side effects are most important | Probably high in iron overloaded subjects* |
Molar iron chelating efficiency; charge of iron (III) complex | High, uncharged | High (hexadentate); charged | Low (bidentate); uncharged | Moderate (tridentate); uncharged |
Important side effects | None or only in iron-depleted subjects | Auditory and retinal toxicity; effects on bones and growth; potential lung toxicity, all at high doses; local skin reactions at infusion sites | Rare but severe agranulocytosis; mild neutropenia; common abdominal discomfort; erosive arthritis | Abdominal discomfort; rash or mild diarrhoea upon initiation of therapy; mild increased creatinine level |
Ability to chelate intracellular cardiac and other tissue iron in humans | High | Probably lower than deferiprone and deferasirox (it is not clear why) | High in clinical and in in vitro studies | Insufficient clinical data available; promising in laboratory studies |