Deferiprone

Warnings and Precautions, Agranulocytosis and Neutropenia (5.1) 3/2025

1 INDICATIONS AND USAGE Deferiprone tablets are indicated for the treatment of transfusional iron overload in adult patients with thalassemia syndromes when current chelation therapy is inadequate. Deferiprone tablets are an iron chelator indicated for the treatment of transfusional iron overload in adult patients with thalassemia syndromes when current chelation therapy is inadequate. ( 1 ) Limitations of Use Safety and effectiveness have not been established for the treatment of transfusional iron overload in patients with myelodysplastic syndrome or in patients with Diamond Blackfan anemia. Limitations of Use Safety and effectiveness have not been established for the treatment of transfusional iron overload in patients with myelodysplastic syndrome or in patients with Diamond Blackfan anemia. Pediatric use information is approved for Chiesi USA, Inc.'s FERRIPROX ® (deferiprone) tablets. However, due to Chiesi USA, Inc.'s marketing exclusivity rights, this drug product is not labeled with that information.

2 DOSAGE AND ADMINISTRATION Deferiprone tablets are available in two formulations. A 1,000 mg formulation and a 500 mg formulation, which have different dosing regimens to achieve the same total daily dosage. ( 2.1 ) To prevent medication errors, before prescribing and dispensing, ensure that the tablet formulation is appropriate for the dosing regimen. Each tablet has distinct identifying characteristics. ( 2.1 , 3 ) Deferiprone tablets (three times a day), 1,000 mg: Starting oral dosage: 75 mg/kg/day (actual body weight) in three divided doses ( 2.3 ) Maximum oral dosage: 99 mg/kg/day (actual body weight) in three divided doses ( 2.3 ) Deferiprone tablets (three times a day), 500 mg: Starting oral dosage: 75 mg/kg/day (actual body weight) in three divided doses ( 2.4 ) Maximum oral dosage: 99 mg/kg/day (actual body weight) in three divided doses ( 2.4 ) 2.1 Important Dosage and Administration Information Deferiprone tablets are available in a 1,000 mg formulation and a 500 mg formulation, which have different oral dosing regimens to achieve the same total daily dosage. Deferiprone tablets (three times a day) - 1,000 mg - given three times a day [see Dosage and Administration (2.3) ] Deferiprone tablets - 500 mg - given three times a day [see Dosage and Administration (2.4) ] To prevent medication errors, before prescribing and dispensing, ensure that the tablet formulation is appropriate for the dosing regimen. Each tablet has distinct identifying characteristics [see Dosage Forms and Strengths (3) ]. For patients who have trouble swallowing tablets, consider the use of oral solution (see the prescribing information for oral solution). Monitoring for Safety Due to the risk of agranulocytosis, monitor ANC before and during deferiprone therapy. Test ANC prior to start of deferiprone therapy and monitor on the following schedule during treatment: First six months of therapy: Monitor ANC weekly; Next six months of therapy: Monitor ANC once every two weeks; After one year of therapy: Monitor ANC every two to four weeks (or at the patient's blood transfusion interval in patients that have not experienced an interruption due to any decrease in ANC [see Warnings and Precautions (5.1) ] . Due to the risk of hepatic transaminase elevations, monitor ALT before and monthly during deferiprone therapy [see Warnings and Precautions (5.2) ] . Due to the risk of zinc deficiency, monitor zinc levels before and regularly during deferiprone therapy [see Warnings and Precautions (5.3) ] . 2.3 Recommended Dosage for 1,000 mg Deferiprone Tablets (three times a day) for Adult Patients with Transfusional Iron Overload due to Thalassemia Syndromes Starting Dosage for Three Times a Day Tablets The recommended starting oral dosage of deferiprone tablets (three times a day) is 75 mg/kg/day (actual body weight), in three divided doses per day. Table 3 describes the number of deferiprone tablets (three times a day) needed to achieve the 75 mg/kg/day total starting dosage). Round dose to the nearest 500 mg (half-tablet). Table 3: Number of Deferiprone 1,000 mg Tablets (three times a day) Needed to Achieve the Total Starting Daily Dosage of 75 mg/kg (rounded to the nearest half-tablet) Body Weight (kg) Morning Midday Evening 20 0.5 0.5 0.5 30 1 0.5 1 40 1 1 1 50 1.5 1 1.5 60 1.5 1.5 1.5 70 2 1.5 2 80 2 2 2 90 2.5 2 2.5 To minimize gastrointestinal upset when first starting therapy, dosing can start at 45 mg/kg/day and increase weekly by 15 mg/kg/day increments until the full prescribed dose is achieved. Dosage Adjustments for Three Times Daily Tablets Tailor dosage adjustments for deferiprone tablets (three times a day) to the individual patient's response and therapeutic goals (maintenance or reduction of body iron burden). The maximum oral dosage is 99 mg/kg/day (actual body weight), in three divided doses per day. Table 4 describes the number of deferiprone tablets (three times a day) needed to achieve the 99 mg/day total maximum daily dosage. Table 4: N …

3 DOSAGE FORMS AND STRENGTHS Tablets (three times a day): 1,000 mg are white, film-coated, oval shaped tablets; imprinted with "T" score "1 K" on one side and plain on the other side. Tablets: 500 mg are white to pinkish-white, capsule-shaped tablets; scored on one side, engraved "T" on the left of the score line and "5" on the right and plain on the other side. Tablets (three times a day): 1,000 mg with functional scoring ( 3 ) Tablets (three times a day): 500 mg with functional scoring ( 3 )

4 CONTRAINDICATIONS Deferiprone is contraindicated in patients with known hypersensitivity to deferiprone or to any of the excipients in the formulations. The following reactions have been reported in association with the administration of deferiprone: Henoch-Schönlein purpura; urticaria; and periorbital edema with skin rash [see Adverse Reactions (6.2) ]. Hypersensitivity to deferiprone or to any of the excipients in the formulations. ( 4 )

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described below and elsewhere in the labeling: Agranulocytosis and Neutropenia [see Warnings and Precautions (5.1) ] Liver Enzyme Elevations [see Warnings and Precautions (5.2) ] Zinc Deficiency [see Warnings and Precautions (5.3) ] The most common adverse reactions in patients with thalassemia (incidence > 6%) are nausea, vomiting, abdominal pain, arthralgia, ALT increased and neutropenia. (5.1, 6) To report SUSPECTED ADVERSE REACTIONS, contact Sun Pharmaceutical Industries, Inc., at 1-866-923-4914 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The following adverse reaction information represents the pooled data collected from single arm or active-controlled clinical trials with deferiprone tablets (three times a day). Thalassemia Syndromes The safety of deferiprone was evaluated in the pooled clinical trial database [see Clinical Studies (14.1)] . Patients received deferiprone tablets (three times a day). Deferiprone was administered orally three times a day (total daily dose either 50, 75, or 99 mg/kg), N=642. Among 642 patients receiving deferiprone, 492 (76.6%) were exposed for 6 months or longer and 365 (56.9%) were exposed for greater than one year. The median age of patients who received deferiprone was 19 years (range 1, 77 years); 50.2% female; 71.2% White, 17.8% Asian, 9.2% Unknown, 1.2% Multi-racial and 0.6% Black. The most serious adverse reaction reported in clinical trials with deferiprone was agranulocytosis [see Warnings and Precautions (5.1) ] . The most common adverse reactions (≥6%) reported during clinical trials were nausea, vomiting, abdominal pain, arthralgia, alanine aminotransferase increased and neutropenia. The table below lists the adverse drug reactions that occurred in at least 1% of patients treated with deferiprone in clinical trials in patients with thalassemia syndromes. Table 7: Adverse reactions occurring in ≥ 1% of deferiprone-treated patients with thalassemia syndromes Body System (N=642) Adverse Reaction % Patients BLOOD AND LYMPHATIC SYSTEM DISORDERS Neutropenia* 7 Agranulocytosis † 1 GASTROINTESTINAL DISORDERS Nausea 13 Abdominal pain/discomfort 10 Vomiting 10 Diarrhea 3 Dyspepsia 2 INVESTIGATIONS Alanine aminotransferase increased 7 Weight increased 2 Aspartate aminotransferase increased 1 METABOLISM AND NUTRITION DISORDERS Increased appetite 4 Decreased appetite 1 MUSCULOSKELETAL AND CONNECTIVE TISSUE DISORDERS Arthralgia 10 Back pain 2 Pain in extremity 2 Arthropathy 1 NERVOUS SYSTEM DISORDERS Headache 2 *Neutropenia includes events of severe neutropenia (ANC ≥0.2 x 10 9 /L and <0.5 x 10 9 /L). †Agranulocytosis (ANC< 0.2 x 10 9 /L) Gastrointestinal symptoms such as nausea, vomiting, and abdominal pain were the most frequent adverse reactions reported by patients participating in clinical trials and led to the discontinuation of deferiprone therapy in 1.6% of patients. Chromaturia (reddish/brown discoloration of the urine) is a result of the excretion of iron in the urine. 6.2 Postmarketing Experience The following additional adverse reactions have been reported in patients receiving deferiprone. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or to establish a causal relationship to drug exposure. Blood and lymphatic system disorders: thrombocytosis, pancytopenia. Cardiac disorders: atrial fibrillation, cardiac failure. Congenital, familial and genetic disorders: hypospadias. Eye disorders: diplopia, papilledema, retinal toxicity. Gastrointestinal disorders: enterocolitis, rectal hemorrhage, gastric ulcer, pancreat …

7 DRUG INTERACTIONS Drugs Associated with Neutropenia or Agranulocytosis: Avoid co-administration. If co-administration is unavoidable, closely monitor the absolute neutrophil count. ( 7.1 ) UGT1A6 Inhibitors: Avoid co-administration. ( 7.2 ) Polyvalent Cations: Allow at least a 4-hour interval between administration of deferiprone and drugs or supplements containing polyvalent cations (e.g., iron, aluminum, or zinc). ( 2.6 , 7.2 ) 7.1 Drugs Associated with Neutropenia or Agranulocytosis Avoid co-administration of deferiprone with other drugs known to be associated with neutropenia or agranulocytosis. If co-administration is unavoidable, closely monitor the absolute neutrophil count [see Warnings and Precautions (5.1) ] . 7.2 Effect of Other Drugs on Deferiprone UDP-Glucuronosyltransferases (UGT) Avoid use of UGT1A6 inhibitors (e.g., diclofenac, probenecid, or silymarin (milk thistle)) with deferiprone [see Dosage and Administration (2) , Adverse Reactions (6.1) , Clinical Pharmacology (12.3) ] . Polyvalent Cations Deferiprone has the potential to bind polyvalent cations (e.g., iron, aluminum, and zinc); allow at least a 4-hour interval between deferiprone and other medications (e.g., antacids), or supplements containing these polyvalent cations [see Dosage and Administration (2.6) ] .

8 USE IN SPECIFIC POPULATIONS Lactation: Advise not to breastfeed. ( 8.2 ) Pediatric use information is approved for Chiesi USA, Inc.'s FERRIPROX® (deferiprone) tablets. However, due to Chiesi USA, Inc.'s marketing exclusivity rights, this drug product is not labeled with that information. 8.1 Pregnancy Risk Summary In animal reproduction studies, oral administration of deferiprone to pregnant rats and rabbits during organogenesis at doses 33% and 49%, respectively, of the maximum recommended human dose (MRHD) resulted in structural abnormalities, embryo-fetal mortality and alterations to growth (see Data ) . The limited available data from deferiprone use in pregnant women are insufficient to inform a drug-associated risk of major birth defects and miscarriage. Based on evidence and developmental toxicity in animal studies, deferiprone can cause fetal harm when administered to a pregnant woman. Advise pregnant women and females of reproductive potential of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes . In the U.S. general population, the estimated background risk of major birth defects and of miscarriage is 2 to 4% and 15 to 20%, respectively. Data Human Data Post-marketing data available from 39 pregnancies of deferiprone-treated patients and 10 pregnancies of partners of deferiprone-treated patients are as follows: Of the 39 pregnancies in deferiprone-treated patients, 23 resulted in healthy newborns, 6 ended in spontaneous abortion, 9 had unknown outcomes, and 1 infant was born with anal atresia, nephroptosis, ventricular septal defect, hemivertebra and urethral fistula. Of the 10 pregnancies in partners of deferiprone-treated patients, 5 resulted in healthy newborns, 1 resulted in a healthy newborn with slight hypospadias, 1 was electively terminated, 1 resulted in the intrauterine death of twins, and 2 had unknown outcomes. Animal Data During organogenesis, pregnant rats and rabbits received deferiprone at oral doses of 0, 30, 80 or 200 mg/kg/day, and 0, 10, 50, or 150 mg/kg/day, respectively. The daily dose was administered as two equal divided doses approximately 7 hours apart. Doses of 200 mg/kg/day in rats and 150 mg/kg/day in rabbits, approximately 33% and 49% of the MRHD, respectively, resulted in increased post-implantation loss and reduced fetal weights in the presence of maternal toxicity (reduced maternal body weight and body weight gain in both rats and rabbits; abnormal large placenta at low incidence in rats). The 200 mg/kg/day dose in rats resulted in external, visceral and skeletal fetal malformations such as cranial malformations, cleft palate, limb malrotation, anal atresia, internal hydrocephaly, anophthalmia and fused bones. The dose of 150 mg/kg/day in rabbits resulted in external fetal malformations (partially opened eyes) and minor blood vessel and skeletal variations. In rats, malformations including micrognathia and persistent ductus arteriosus could be observed in the absence of maternal toxicity at doses equal to or greater than 30 and 80 mg/kg/day, approximately 5% and 13% of the MHRD, respectively. 8.2 Lactation Risk Summary There is no information regarding the presence of deferiprone in human milk, the effects on the breastfed child, or the effects on milk production. Because of the potential for serious adverse reactions in the breastfed child, including the potential for tumorigenicity shown for deferiprone in animal studies, advise patients that breastfeeding is not recommended during treatment with deferiprone, and for at least 2 weeks after the last dose. 8.3 Females and Males of Reproductive Potential Pregnancy Testing Pregnancy testing is recommended for females of reproductive potential prior to initiating deferiprone. Contraception Females Deferiprone can cause embryo-fetal harm when administered to a …

12.1 Mechanism of Action Deferiprone is a chelating agent with an affinity for ferric ions (iron III). Deferiprone binds with ferric ions to form neutral 3:1 (deferiprone:iron) complexes that are stable at physiological pH.

11 DESCRIPTION Deferiprone Tablets contain 1,000 mg or 500 mg deferiprone (3-hydroxy-1,2-dimethylpyridin-4-one), a synthetic, orally active, iron-chelating agent. The molecular formula for deferiprone is C 7 H 9 NO 2 and its molecular weight is 139.15 g/mol. Deferiprone has the following structural formula: Deferiprone is a white to pinkish-white powder. It is sparingly soluble in deionized water (14.3 mg/mL) and has a melting point range of 272°C to 278°C. Chemical Structure Deferiprone Tablets (three times a day), 1,000 mg White, film-coated, oval shaped tablets; imprinted with "T" score "1 K" on one side and plain on the other. The tablets can be broken in half along the score line. Each tablet contains 1,000 mg deferiprone and the following inactive ingredients: Tablet core - crospovidone, magnesium stearate and methylcellulose; Coating - copovidone, hypromellose, medium chain triglycerides, polydextrose, polyethylene glycol and titanium dioxide. Deferiprone Tablets 500 mg White to pinkish-white, capsule-shaped tablets; scored on one side, engraved "T" on the left of the score line and "5" on the right and plain on the other side. The tablets can be broken in half along the score line. Each tablet contains 500 mg deferiprone and the following inactive ingredients: Tablet core - colloidal silicon dioxide, magnesium stearate, and microcrystalline cellulose.

10 OVERDOSAGE No cases of acute overdose have been reported. There is no specific antidote to deferiprone overdose. Neurological disorders such as cerebellar symptoms, diplopia, lateral nystagmus, psychomotor slowdown, hand movements and axial hypotonia have been observed in children treated with 2.5 to 3 times the recommended dose for more than one year. The neurological disorders progressively regressed after deferiprone discontinuation.

16 HOW SUPPLIED/STORAGE AND HANDLING Deferiprone Tablets (three times a day), 1,000 mg White, film-coated, oval shaped tablets; imprinted with "T" score "1 K" on one side and plain on the other. The tablets can be broken in half along the score line. They are provided in HDPE bottles. 1,000 mg film-coated tablets, 50 tablets NDC 51672-4237-4 Keep the bottle tightly closed to protect from moisture. Store at 20°C to 25°C (68°F to 77°F) ; [see USP Controlled Room Temperature]. Deferiprone Tablets, 500 mg White to pinkish-white, capsule-shaped tablets; scored on one side, engraved "T" on the left of the score line and "5" on the right and plain on the other side. They are provided in a 100 count HDPE bottle with a child-resistant cap. 500 mg tablets, 100 tablets NDC 51672-4196-1 Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].