Sebelipase alfa

12.1 Mechanism of Action LAL deficiency is an autosomal recessive lysosomal storage disorder characterized by a genetic defect resulting in a marked decrease or loss in activity of the lysosomal acid lipase (LAL) enzyme. The primary site of action of the LAL enzyme is the lysosome, where the enzyme normally causes the breakdown of lipid particles, including LDL-c and triglycerides. Deficient LAL enzyme activity results in progressive complications due to the lysosomal accumulation of cholesteryl esters and triglycerides in multiple organs, including the liver, spleen, intestine, and the walls of blood vessels. The resulting lipid accumulation in the liver may lead to increased liver fat content and progression of liver disease, including fibrosis and cirrhosis. Lipid accumulation in the intestinal wall leads to malabsorption and growth failure. In parallel, dyslipidemia due to impaired degradation of lysosomal lipid is common with elevated LDL-c and triglycerides and low HDL-cholesterol (HDL-c). Sebelipase alfa binds to cell surface receptors via glycans expressed on the protein and is subsequently internalized into lysosomes. Sebelipase alfa catalyzes the lysosomal hydrolysis of cholesteryl esters and triglycerides to free cholesterol, glycerol and free fatty acids.

1 INDICATIONS AND USAGE KANUMA ® is indicated for the treatment of patients with a diagnosis of Lysosomal Acid Lipase (LAL) deficiency. KANUMA ® is a hydrolytic lysosomal cholesteryl ester and triacylglycerol-specific enzyme indicated for the treatment of patients with a diagnosis of Lysosomal Acid Lipase (LAL) deficiency. ( 1 )

2 DOSAGE AND ADMINISTRATION Administration of KANUMA should be supervised by a healthcare provider knowledgeable in the management of hypersensitivity reactions including anaphylaxis. ( 2.1 ) Infants with Rapidly Progressive LAL Deficiency Presenting within the First 6 Months of Life: The recommended starting dosage is 1 mg/kg as an intravenous infusion once weekly. ( 2.2 ) For patients with a suboptimal clinical response, increase the dosage to 3 mg/kg once weekly. ( 2.2 ) For patients with continued suboptimal clinical response, further increase the dosage to 5 mg/kg once weekly. ( 2.2 ) Pediatric and Adult Patients with LAL Deficiency: The recommended dosage is 1 mg/kg as an intravenous infusion once every other week. ( 2.2 ) For patients with a suboptimal clinical response, increase the dosage to 3 mg/kg once every other week. ( 2.2 ) See Full Prescribing Information for complete Dosage and Administration Information. Administration Instructions Infuse over at least 2 hours. ( 2.4 ) Consider further prolonging the infusion time for patients receiving dosages greater than 1 mg/kg or for those who have experienced a hypersensitivity reaction. ( 2.4 ) Consider a 1-hour infusion for the 1 mg/kg dose in patients who tolerate the infusion. ( 2.4 ) 2.1 Recommendations Prior to KANUMA Treatment Administration of KANUMA should be supervised by a healthcare provider knowledgeable in the management of hypersensitivity reactions including anaphylaxis [see Warnings and Precautions (5.1) ]. Initiate KANUMA in a healthcare setting with appropriate medical monitoring and support measures, including access to cardiopulmonary resuscitation equipment [see Warnings and Precautions (5.1) ]. 2.2 Recommended Dosage Infants with Rapidly Progressive LAL Deficiency Presenting within the First 6 Months of Life: The recommended starting dosage is 1 mg/kg administered as an intravenous infusion once weekly. For patients with a suboptimal clinical response, increase the dosage to 3 mg/kg once weekly. For patients with continued suboptimal clinical response on the 3 mg/kg once weekly dosage, further increase the dosage to 5 mg/kg once weekly. A suboptimal clinical response is defined as any of the following: poor growth, deteriorating biochemical markers, or persistent or worsening organomegaly. Pediatric and Adult Patients with LAL Deficiency: The recommended dosage is 1 mg/kg administered as an intravenous infusion once every other week. For patients with a suboptimal clinical response, increase the dosage to 3 mg/kg once every other week. A suboptimal clinical response is defined as any of the following: poor growth, deteriorating biochemical markers [e.g., alanine aminotransferase (ALT), aspartate aminotransferase (AST)], and/or parameters of lipid metabolism [e.g., low-density lipoprotein cholesterol (LDL-c), triglycerides (TG)]. 2.3 Preparation Instructions KANUMA is for intravenous infusion only. Prepare KANUMA using the following steps. Determine the number of vials needed based on the patient's weight and the recommended dose of 1 mg/kg, 3 mg/kg, or 5 mg/kg using the following calculations (a-b): Total dose (mg) = Patient's weight (kg) × Recommended dose (mg/kg) Total number of vials = Total dose (mg) divided by 20 mg/vial Round to the next whole vial and remove the required number of vials from the refrigerator to allow them to reach room temperature. Volume (mL) of calculated total dose = Total dose (mg) divided by the 2 mg/mL concentration Volume (mL) of 0.9% Sodium Chloride for dilution = Total infusion volume (mL) for patient's weight (see Table 1 ) - Volume (mL) of calculated total dose Table 1: Total Infusion Volumes The infusion volume should be based on the prescribed dose and should be prepared to a final KANUMA concentration of 0.1 mg/mL to 1.5 mg/mL. Weight Range (kg) 1 mg/kg dose 3 mg/kg dose 5 mg/kg dose Total Infusion Volume (mL) Total Infusion Volume (mL) Total Infusion Volume (mL) 1 to 2.9 4 8 12 3 to 5.9 6 12 20 6 to 10.9 10 25 50 11 to 24.9 25 50 150 25 to 49.9 50 100 250 50 to 99.9 100 250 500 100 to 120.9 250 500 600 Mix gently by inversion. Do not shake the vials or the prepared infusion. The solution should be inspected visually for particulate matter and discoloration prior to administration. The solution should be a clear to slightly opalescent, colorless to slightly colored solution. Thin, translucent particles or fibers may be present in the vials or diluted solution. Do not use if the solution is cloudy or if other particulate matter is observed. Vials are for single-use only. Discard any unused product. Do not freeze. 2.4 Administration Instructions Administer the diluted solution as an intravenous infusion using a low-protein binding infusion set with an in-line, low-protein binding 0.2 micron filter. Infuse over at least 2 hours. Consider further prolonging the infusion time for patients receiving dosages greater than 1 mg/kg or those who have experienced hypersensitivity reactions [see Warning

6 ADVERSE REACTIONS The most common adverse reactions are: Infants with Rapidly Progressive LAL Deficiency Presenting within the First 6 Months of Life (≥30%): diarrhea, vomiting, fever, rhinitis, anemia, cough, nasopharyngitis, and urticaria. ( 6.1 ) Pediatric and Adult Patients with LAL Deficiency (≥8%): headache, fever, oropharyngeal pain, nasopharyngitis, asthenia, constipation, and nausea. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Alexion at 1-844-259-6783 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch 6.1 Clinical 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 clinical practice. In clinical trials, a total of 106 patients received treatment with KANUMA. The data described below reflect exposure to KANUMA in 75 patients who received KANUMA at dosages up to 3 mg/kg once weekly in clinical trials: Nine patients (5 males, 4 females) who had growth failure or other evidence of rapidly progressive LAL deficiency presenting within the first 6 months of life received KANUMA for up to 165 weeks (median 60 weeks) at escalating doses ranging between 0.35 mg/kg and 5 mg/kg once weekly [see Clinical Studies (14.1) ] . 66 pediatric and adult patients with LAL deficiency aged 4 to 58 years (33 males, 33 females) received KANUMA 1 mg/kg every other week for up to 36 weeks. Table 2 summarizes the most common adverse reactions occurring in >30% of patients with rapidly progressive LAL deficiency presenting within the first 6 months of life receiving KANUMA in Study 1. Table 2: Adverse Reactions in ≥30% of Infants with Rapidly Progressive LAL Deficiency Presenting within the First 6 Months of Life Receiving KANUMA Adverse Reactions KANUMA N=9 n (%) Diarrhea 6 (67) Vomiting 6 (67) Fever 5 (56) Rhinitis 5 (56) Anemia 4 (44) Cough 3 (33) Nasopharyngitis 3 (33) Urticaria 3 (33) Other less common adverse reactions reported in patients with rapidly progressive disease presenting within the first 6 months of life who received KANUMA included hypotonia, decreased oxygen saturation, retching, sneezing, and tachycardia. For infant patients within Study 1 and Study 3 (n = 19), the following additional adverse reactions were reported in ≥ 30% of infants who received KANUMA since the time of marketing authorization, including patients who received an escalated dose to 5 mg/kg qw: hypersensitivity, respiratory distress, and tachycardia. Table 3 summarizes the most common adverse reactions that occurred in ≥8% of pediatric and adult patients with LAL deficiency receiving KANUMA in Study 2. Table 3: Adverse Reactions in ≥8% of Pediatric and Adult Patients with LAL Deficiency Receiving KANUMA Adverse Reactions KANUMA N = 36 Placebo N = 30 n (%) n (%) Headache 10 (28) 6 (20) Fever 9 (25) 7 (23) Oropharyngeal pain 6 (17) 1 (3) Nasopharyngitis 4 (11) 3 (10) Asthenia 3 (8) 1 (3) Constipation 3 (8) 1 (3) Nausea 3 (8) 2 (7) Other less common adverse reactions reported in pediatric and adult patients who received KANUMA included anxiety and chest discomfort. For pediatric and adult patients (n = 106), the following additional adverse reactions were reported in ≥ 8% of pediatric and adult patients who received KANUMA since the time of marketing authorization, including patients who received an escalated dose to 3 mg/kg qw: hypersensitivity, diarrhea, abdominal pain, and dizziness. Hyperlipidemia Increases in circulating LDL-cholesterol (LDL-c) and triglycerides above pre-treatment values were observed in 29 of 36 (81%) and 21 of 36 (58%) patients, respectively, at 2 and 4 weeks following initiation of KANUMA [see Clinical Pharmacology (12.2) ] . The maximum mean percentage increase was 18% for LDL-c at Week 2 and 5% for triglycerides at Week 4. 6.2 Immunogenicity As with all therapeutic proteins, there is potential for immunogenicity. The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay and may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies in the studies described below with the incidence of antibodies in other studies or to other sebelipase alfa products may be misleading. Approximately 8% (9/106) of pediatric and adult patients with LAL deficiency developed antibodies to sebelipase alfa (anti-drug antibodies or ADA) following treatment with KANUMA across all clinical studies. Among the 9 patients who developed ADA, 2 patients were positive for neutralizing antibodies (NAb). Approximately 53% (10/19) of infants with rapidly progressive LAL deficiency developed ADA following treatment with KANUMA across all clinical studies. Among the 10 patients who developed ADA, 9 patients were positive