A 28-year-old Indian woman with β-thalassemia major presents with iron overload complications including cardiac arrhythmias and hepatic cirrhosis. She has received multiple blood transfusions over 20 years. Which iron chelator is the drug of choice for preventing further myocardial iron deposition in this patient?

Explanation

## Iron Chelation in Thalassemia Major: Cardiac Iron Overload **Key Point:** Deferiprone (L1) is the drug of choice for myocardial iron overload in thalassemia major due to its unique ability to penetrate cardiomyocytes and chelate intracellular iron. ### Why Deferiprone? **High-Yield:** Deferiprone is a bidentate oral iron chelator with the smallest molecular size among the three available chelators, enabling superior myocardial cell penetration. Multiple randomized controlled trials (including the CORDELIA trial) have demonstrated that deferiprone achieves significantly greater improvement in myocardial T2* (cardiac MRI marker of iron load) compared to deferoxamine, and is superior to deferasirox for cardiac iron clearance. | Feature | Deferiprone | Deferasirox | Deferoxamine | |---------|-------------|-------------|--------------| | **Route** | Oral (3× daily) | Oral (once daily) | IV/SC infusion (8–12 hrs) | | **Cardiac penetration** | **Superior (drug of choice)** | Moderate | Moderate | | **Myocardial T2* improvement** | Fastest / most effective | Moderate | Slower | | **Mechanism** | Bidentate; enters cardiomyocytes | Tridentate | Hexadentate | | **Key risk** | Agranulocytosis (1–2%) — weekly CBC mandatory | Renal toxicity | Auditory/ocular toxicity | | **Combination use** | Often combined with deferoxamine for severe cardiac overload | Second-line for cardiac | First-line for non-cardiac overload | **Clinical Pearl (Anderson et al., Lancet 2002; CORDELIA trial, NEJM 2011):** In patients with established cardiac iron overload (arrhythmias, reduced ejection fraction, elevated myocardial iron on T2* MRI), deferiprone is the preferred agent. Its small molecular size allows it to cross the cardiomyocyte membrane and chelate labile iron within the cell — a property not shared to the same degree by deferoxamine or deferasirox. For severe cardiac siderosis, deferiprone + deferoxamine combination is used. **Why not the other options?** - **Deferasirox (A):** Excellent for hepatic and systemic iron overload; first-line for chronic transfusional iron overload in general, but NOT the drug of choice specifically for myocardial iron — cardiac penetration is inferior to deferiprone. - **Deferoxamine (B):** Parenteral, effective for acute iron poisoning and general overload; slower myocardial iron clearance; used in combination with deferiprone for severe cardiac siderosis. - **Vitamin C alone (D):** Vitamin C is used as an adjunct to deferoxamine to enhance iron excretion; it has no standalone chelation efficacy and is never used alone for iron overload. ### Monitoring Requirements for Deferiprone - **Weekly CBC** (to detect agranulocytosis — absolute neutrophil count must be monitored) - Liver function tests - Cardiac MRI T2* (annually or more frequently in cardiac overload) - Serum ferritin (every 3 months) **Reference:** Cappellini MD et al. *Guidelines for the Management of Transfusion Dependent Thalassaemia (TDT)*, 4th ed., Thalassaemia International Federation, 2021; KD Tripathi, *Essentials of Medical Pharmacology*, 8th ed.