Deferasirox

12.1 Mechanism of Action Deferasirox is an orally active chelator that is selective for iron (as Fe 3+ ). It is a tridentate ligand that binds iron with high affinity in a 2:1 ratio. Although deferasirox has very low affinity for zinc and copper, there are variable decreases in the serum concentration of these trace metals after the administration of deferasirox. The clinical significance of these decreases is uncertain.

1 INDICATIONS AND USAGE Deferasirox tablets are an iron chelator indicated for the treatment of chronic iron overload due to blood transfusions in patients 2 years of age and older. ( 1.1 ) Deferasirox tablets are indicated for the treatment of chronic iron overload in patients 10 years of age and older with non-transfusion-dependent thalassemia (NTDT) syndromes, and with a liver iron (Fe) concentration (LIC) of at least 5 mg Fe per gram of dry weight (Fe/g dw) and a serum ferritin greater than 300 mcg/L.( 1.2 ) Limitations of Use The safety and efficacy of deferasirox tablets when administered with other iron chelation therapy have not been established. ( 1.3 ) 1.1 Treatment of Chronic Iron Overload Due to Blood Transfusions (Transfusional Iron Overload) Deferasirox tablets are indicated for the treatment of chronic iron overload due to blood transfusions (transfusional hemosiderosis) in patients 2 years of age and older. 1.2 Treatment of Chronic Iron Overload in Non-Transfusion-Dependent Thalassemia Syndromes Deferasirox tablets are indicated for the treatment of chronic iron overload in patients 10 years of age and older with non-transfusion-dependent thalassemia (NTDT) syndromes and with a liver iron concentration (LIC) of at least 5 milligrams of iron per gram of liver dry weight (mg Fe/g dw) and a serum ferritin greater than 300 mcg/L. 1.3 Limitations of Use The safety and efficacy of deferasirox tablets when administered with other iron chelation therapy have not been established.

2 DOSAGE AND ADMINISTRATION Transfusional Iron Overload: Initial dose for patients with estimated glomerular filtration rate (eGFR) greater than 60 mL/min/1.73 m 2 is 14 mg per kg (calculated to nearest whole tablet ) once daily. ( 2.1 ) NTDT Syndromes: Initial dose for patients with eGFR greater than 60 mL/min/1.73 m 2 is 7 mg per kg (calculated to nearest whole tablet) once daily. ( 2.2 ) See full prescribing information for information regarding monitoring, administration, and dose-reductions for organ impairment. ( 2.1 , 2,2 , 2.3 , 2.4 ) 2.1Transfusional Iron Overload Deferasirox tablets therapy should only be considered when a patient has evidence of chronic transfusional iron overload. The evidence should include the transfusion of at least 100 mL/kg of packed red blood cells (e.g., at least 20 units of packed red blood cells for a 40 kg person or more in individuals weighing more than 40 kg), and a serum ferritin consistently greater than 1,000 mcg/L. Prior to starting therapy, or increasing dose, evaluate: Serum ferritin level Obtain renal function Obtain serum creatinine in duplicate (due to variations in measurements). Calculate the estimated glomerular filtration rate (eGFR). Use a prediction equation appropriate for adult patients (e.g., CKD-EPI, MDRD method) and in pediatric patients (e.g., Schwartz equations). Obtain urinalyses and serum electrolytes to evaluate renal tubular function [ see Dosage and Administration (2.4) , Warnings and Precautions (5.1)]. Serum transaminases and bilirubin [ see Dosage and Administration (2.4), Warnings and Precautions (5.2)] Baseline auditory and ophthalmic examinations [see Warnings and Precautions (5.10)] Initiating Therapy: The recommended initial dose of deferasirox tablets for patients 2 years of age and older with eGFR greater than 60 mL/min/1.73 m 2 is 14 mg per kg body weight orally, once daily. Calculate doses (mg per kg per day) to the nearest whole tablet. Changes in weight of pediatric patients over time must be taken into account when calculating the dose. During Therapy: Monitor serum ferritin monthly and adjust the dose of deferasirox tablets, if necessary, every 3 to 6 months based on serum ferritin trends. Use the minimum effective dose to achieve a trend of decreasing ferritin Make dose adjustments in steps of 3.5 or 7 mg per kg and tailor adjustments to the individual patient’s response and therapeutic goals. In patients not adequately controlled with doses of 21 mg per kg (e.g., serum ferritin levels persistently above 2,500 mcg/L and not showing a decreasing trend over time), doses of up to 28 mg per kg may be considered. Doses above 28 mg per kg are not recommended [ see Warnings and Precautions (5.6)]. Adjust dose based on serum ferritin levels If the serum ferritin falls below 1,000 mcg/L at 2 consecutive visits, consider dose reduction especially if the deferasirox tablets dose is greater than 17.5 mg/kg/day [see Adverse Reactions (6.1)]. If the serum ferritin falls below 500 mcg/L, interrupt deferasirox tablets therapy to minimize the risk of overchelation, and continue monthly monitoring [ see Warnings and Precautions (5.6)] . Evaluate the need for ongoing chelation therapy for patients whose conditions no longer require regular blood transfusions. Use the minimum effective dose to maintain iron burden in the target range [see Warnings and Precautions (5.6)]. Monitor blood counts, liver function, renal function and ferritin monthly [see Warnings and Precautions (5.1 , 5.2 , 5.4 )]. Interrupt deferasirox tablets for pediatric patients who have acute illnesses, which can cause volume depletion, such as vomiting, diarrhea, or prolonged decreased oral intake, and monitor more frequently. Resume therapy as appropriate, based on assessments of renal function, when oral intake and volume status are normal [see Dosage and Administration ( 2.4 , 2.5 ), Warnings and Precautions ( 5.1) , Use in Specific Populations ( 8.4), Clinical Pharmacology ( 12.3)]. 2.2 Iron Overload in Non-Transfusion-Dependent Thalassemia Syndromes Deferasirox tablets therapy should only be considered when a patient with NTDT syndrome has an LIC of at least 5 mg Fe/g dw and a serum ferritin greater than 300 mcg/L. Prior to starting therapy, obtain: LIC by liver biopsy or by an FDA-cleared or approved method for identifying patients for treatment with deferasirox therapy Serum ferritin level on at least 2 measurements 1-month apart [ see Clinical Studies (14)] Baseline renal function: Obtain serum creatinine in duplicate (due to variations in measurements). Calculate the estimated glomerular filtration rate (eGFR). Use a prediction equation appropriate for adult patients (e.g., CKD-EPI, MDRD method) and in pediatric patients (e.g., Schwartz equations). Obtain urinalyses and serum electrolytes to evaluate renal tubular function [ see Dosage and Administration (2.4), Warnings and Precautions (5.1)]. Serum transaminases and bilirubin [ see Dosage and Administration (2.4),

6 ADVERSE REACTIONS The following clinically significant adverse reactions are also discussed in other sections of the labeling: Acute Kidney Injury, Including Acute Renal Failure Requiring Dialysis, and Renal Tubular Toxicity Including Fanconi Syndrome [ see Warnings and Precautions (5.1,5.6)] Hepatic Toxicity and Failure [ see Warnings and Precautions (5.2,5.6)] GI Hemorrhage [ see Warnings and Precautions (5.3 )] Bone Marrow Suppression [ see Warnings and Precautions (5.4)] Hypersensitivity [see Warnings and Precautions (5.7) ] Severe Skin Reactions [see Warnings and Precautions (5.8) ] Skin Rash [see Warnings and Precautions (5.9)] Auditory and Ocular Abnormalities [see Warnings and Precautions (5.10) ] In patients with transfusional iron overload, the most frequently occurring (greater than 5%) adverse reactions are diarrhea, vomiting, nausea, abdominal pain, skin rashes, and increases in serum creatinine.In deferasirox-treated patients with NTDT syndromes, the most frequently occurring (greater than 5%) adverse reactions are diarrhea, rash, and nausea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact MSN Pharmaceuticals Inc. at 1-855-668-2369 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1Clinical Trials 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. Deferasirox was evaluated in healthy volunteer trials. Currently, there are no clinical data in patients with deferasirox tablets. Deferasirox contains the same active ingredient as deferasirox tablets for oral suspension. The following adverse reactions have been reported with deferasirox tablets for oral suspension. Transfusional Iron Overload A total of 700 adult and pediatric patients were treated with deferasirox for 48 weeks in premarketing studies. These included 469 patients with beta-thalassemia, 99 with rare anemias, and 132 with sickle cell disease. Of these patients, 45% were male, 70% were Caucasian, and 292 patients were less than 16 years of age. In the sickle cell disease population, 89% of patients were black. Median treatment duration among the sickle cell patients was 51 weeks. Of the 700 patients treated, 469 (403 beta-thalassemia and 66 rare anemias) were entered into extensions of the original clinical protocols. In ongoing extension studies, median durations of treatment were 88 to 205 weeks. Six hundred twenty-seven (627) patients with myelodysplastic syndrome (MDS) were enrolled across 5 uncontrolled trials. These studies varied in duration from 1 to 5 years. The discontinuation rate across studies in the first year was 46% (Adverse Events (AEs) 20%, withdrawal of consent 10%, death 8%, other 4%, lab abnormalities 3%, and lack of efficacy 1%). Among 47 patients enrolled in the study of 5-year duration, 10 remained on deferasirox at the completion of the study. Table 1 displays adverse reactions occurring in greater than 5% of deferasirox-treated beta-thalassemia patients (Study 1), sickle cell disease patients (Study 3), and patients with MDS (MDS pool). Abdominal pain, nausea, vomiting, diarrhea, skin rashes, and increases in serum creatinine were the most frequent adverse reactions reported with a suspected relationship to deferasirox. Gastrointestinal symptoms, increases in serum creatinine, and skin rash were dose related. Table 1. Adverse Reactions a Occurring in >5% of Deferasirox-treated Patients in Study 1, Study 3, and MDS Pool Study 1 (Beta-thalassemia) Study 3 (Sickle Cell Disease) MDS Pool Adverse Reactions Deferasirox N=296 n(%) Deferoxamine N=290 n(%) Deferasirox N=132 n(%) Deferoxamine N=63 n(%) Deferasirox N=627 n(%) Abdominal Pain b 63 (21) 41 (14) 37 (28) 9 (14) 145 (23) Diarrhea 35 (12) 21 (7) 26 (20) 3 (5) 297 (47) Creatinine Increased c 33 (11) 0 (0) 9 (7) 0 89 (14) Nausea 31 (11) 14 (5) 30 (23) 7 (11) 161 (26) Vomiting 30 (10) 28 (10) 28 (21) 10 (16) 83 (13) Rash 25 (8) 9 (3) 14 (11) 3 (5) 83 (13) Abbreviation: MDS, myelodysplastic syndrome. a Adverse reaction frequencies are based on AEs reported regardless of relationship to study drug. b Includes ‘abdominal pain’, ‘abdominal pain lower’, and ‘abdominal pain upper.’ C Includes ‘blood creatinine increased’ and ‘blood creatinine abnormal’. See also Table 2. In Study 1, a total of 113 (38%) patients treated with deferasirox had increases in serum creatinine greater than 33% above baseline on 2 separate occasions (Table 2) and 25 (8%) patients required dose reductions. Increases in serum creatinine appeared to be dose related [see Warnings and Precautions (5.1)] . In this study, 17 (6%) patients treated with deferasirox developed elevations in serum glutamic-pyruvic transaminase (SGPT)/ALT levels greater than 5 times the upper limit of normal (ULN) at 2 consecutive visits. Of these, 2 patients had liver biopsy proven drug-in

7 DRUG INTERACTIONS Do not take deferasirox with aluminum-containing antacid preparations.( 7.1 ) Deferasirox increases the exposure of the repaglinide. Consider repaglinide dose reduction and monitor blood glucose levels. ( 7.3 ) Avoid the use of deferasirox with theophylline as theophylline levels could be increased. ( 7.4 ) Deferasirox increases exposure of busulfan. Monitor plasma concentrations of busulfan when coadministered with deferasirox to allow dose adjustment of busulfan, as needed. ( 7.7 ) 7.1Aluminum-Containing Antacid Preparations The concomitant administration of deferasirox and aluminum-containing antacid preparations has not been formally studied. Although deferasirox has a lower affinity for aluminum than for iron, do not take deferasirox with aluminum-containing antacid preparations. 7.2Agents Metabolized by CYP3A4 Deferasirox may induce CYP3A4 resulting in a decrease in CYP3A4 substrate concentration when these drugs are coadministered. Closely monitor patients for signs of reduced effectiveness when deferasirox is administered with drugs metabolized by CYP3A4 (e.g., alfentanil, aprepitant, budesonide, buspirone, conivaptan, cyclosporine, darifenacin, darunavir, dasatinib, dihydroergotamine, dronedarone, eletriptan, eplerenone, ergotamine, everolimus, felodipine, fentanyl, hormonal contraceptive agents, indinavir, fluticasone, lopinavir, lovastatin, lurasidone, maraviroc, midazolam, nisoldipine, pimozide, quetiapine, quinidine, saquinavir, sildenafil, simvastatin, sirolimus, tacrolimus, tolvaptan, tipranavir, triazolam, ticagrelor, and vardenafil) [ see Clinical Pharmacology (12.3)]. 7.3Agents Metabolized by CYP2C8 Deferasirox inhibits CYP2C8 resulting in an increase in CYP2C8 substrate (e.g., repaglinide and paclitaxel) concentration when these drugs are coadministered. If deferasirox and repaglinide are used concomitantly, consider decreasing the dose of repaglinide and perform careful monitoring of blood glucose levels. Closely monitor patients for signs of exposure related toxicity when deferasirox is coadministered with other CYP2C8 substrates [ see Clinical Pharmacology (12.3)]. 7.4Agents Metabolized by CYP1A2 Deferasirox inhibits CYP1A2 resulting in an increase in CYP1A2 substrate (e.g., alosetron, caffeine, duloxetine, melatonin, ramelteon, tacrine, theophylline, tizanidine) concentration when these drugs are coadministered. An increase in theophylline plasma concentrations could lead to clinically significant theophylline induced CNS or other adverse reactions. Avoid the concomitant use of theophylline or other CYP1A2 substrates with a narrow therapeutic index (e.g., tizanidine) with deferasirox. Monitor theophylline concentrations and consider theophylline dose modification if you must coadminister theophylline with deferasirox. Closely monitor patients for signs of exposure related toxicity when Deferasirox is coadministered with other drugs metabolized by CYP1A2 [ see Clinical Pharmacology (12.3)]. 7.5Agents Inducing UDP-glucuronosyltransferase (UGT) Metabolism Deferasirox is a substrate of UGT1A1 and to a lesser extent UGT1A3. The concomitant use of deferasirox with strong UGT inducers (e.g., rifampicin, phenytoin, phenobarbital, ritonavir) may result in a decrease in deferasirox efficacy due to a possible decrease in deferasirox concentration. Avoid the concomitant use of strong UGT inducers with deferasirox. Consider increasing the initial dose of deferasirox if you must coadminister these agents together [ see Dosage and Administration ( 2.5 ), Clinical Pharmacology (12.3)]. 7.6Bile Acid Sequestrants Avoid the concomitant use of bile acid sequestrants (e.g., cholestyramine, colesevelam, colestipol) with deferasirox due to a possible decrease in deferasirox concentration. If you must coadminister these agents together, consider increasing the initial dose of deferasirox [ see Dosage and Administration ( 2.5 ), Clinical Pharmacology (12.3)]. 7.7 Busulfan Increased exposure of busulfan was observed with concomitant use with deferasirox. Monitor plasma concentrations of busulfan when coadministered with deferasirox to allow dose adjustment of busulfan as needed [ see Clinical Pharmacology (12.3)].