Agalsidase beta

12.1 Mechanism of Action FABRAZYME (agalsidase beta) provides an exogenous source of α-galactosidase A in Fabry disease patients. Agalsidase beta is internalized and transported into lysosomes where it exerts enzymatic activity and reduces accumulated GL-3.

1 INDICATIONS AND USAGE FABRAZYME ® is indicated for the treatment of adult and pediatric patients 2 years of age and older with confirmed Fabry disease. FABRAZYME is a hydrolytic lysosomal neutral glycosphingolipid-specific enzyme indicated for the treatment of adult and pediatric patients 2 years of age and older with confirmed Fabry disease. ( 1 )

2 DOSAGE AND ADMINISTRATION Administration of FABRAZYME should be supervised by a healthcare provider knowledgeable in the management of hypersensitivity reactions including anaphylaxis. ( 2.1 ) The recommended dosage is 1 mg/kg body weight given every two weeks as an intravenous infusion. ( 2.2 ) See the full prescribing information for rechallenge, preparation, storage, and administration instructions. ( 2.3 , 2.4 , 2.5 , 2.6 ) 2.1 Recommendations Prior to FABRAZYME Treatment Administration of FABRAZYME should be supervised by a healthcare provider knowledgeable in the management of hypersensitivity reactions including anaphylaxis [see Warnings and Precautions (5.1) ]. Initiate FABRAZYME in a healthcare setting with appropriate medical monitoring and support measures, including access to cardiopulmonary resuscitation equipment [see Warnings and Precautions (5.1) ]. Prior to FABRAZYME administration, consider pretreating with antihistamines, antipyretics, and/or corticosteroids [see Warnings and Precautions (5.1 , 5.2) ] . FABRAZYME must be reconstituted and diluted prior to use [see Dosage and Administration (2.4) ] 2.2 Recommended Dosage and Administration The recommended dosage of FABRAZYME is 1 mg/kg body weight infused every two weeks as an intravenous infusion. The initial recommended infusion rate is 0.25 mg/min (15 mg/hour) [see Dosage and Administration (2.6) ] . 2.3 Rechallenge Instructions Patients who have had a positive skin test to FABRAZYME or who have tested positive for anti-FABRAZYME IgE may be successfully rechallenged with FABRAZYME. The initial rechallenge administration should be a low dose at a lower infusion rate, e.g., one-half the therapeutic dose (0.5 mg/kg) at 1/25 th of the initial standard recommended rate (0.01 mg/min or 0.6 mg/hr). Once a patient tolerates the infusion, the dose may be increased to reach the approved dose of 1 mg/kg and the infusion rate may be increased by slowly titrating upwards (doubled every 30 minutes up to a maximum rate of 0.25 mg/minute), as tolerated [see Adverse Reactions (6.2) ] . 2.4 Preparation Instructions Use aseptic technique during preparation. Reconstitute and dilute FABRAZYME in the following manner: Reconstitution Instructions 1. Determine the number of 35 mg and 5 mg FABRAZYME vials to be reconstituted based on actual body weight (kg) and the recommended dose [see Dosage and Administration (2.2) ] . 2. Remove the required number of 35 mg and 5 mg FABRAZYME vials from the refrigerator and allow the vials to sit for approximately 30 minutes at room temperature 20°C to 25°C (68°F to 77°F) before use. 3. Reconstitute each vial by directing the diluent down the inside wall of each vial then gently tilt and roll each vial. Use the following volumes for reconstitution: 7.2 mL of FABRAZYME Sterile Water for Injection into the 35 mg vial. Total extractable amount per vial is 35 mg, 7 mL. 1.1 mL of Sterile Water for Injection into the 5 mg vial. Total extractable amount per vial is 5 mg, 1 mL. 4. Each reconstituted vial will yield a concentration of 5 mg/mL of agalsidase beta. 5. Do not shake or agitate the product. 6. Visually inspect the reconstituted solution in the vials for particulate matter and discoloration. The reconstituted solution should be clear and colorless. Discard if visible particulate matter is present or the solution is discolored. Dilution Instructions 7. Select an appropriate size 0.9% Sodium Chloride Injection infusion bag and prepare by removing a volume equal to the required FABRAZYME volume to achieve a total volume per Table 1. 8. Slowly withdraw the required volume of reconstituted solution from the FABRAZYME vial(s). Discard any unused reconstituted solution remaining in the vial. Table 1: Total Infusion Volume Based on Patient Weight Patient Weight (kg) Total Volume (mL) ≤35 50 35.1 to 70 100 70.1 to 100 250 >100 500 9. Gently inject the FABRAZYME reconstituted solution into the port of the 0.9% Sodium Chloride Injection infusion bag. Do not inject into the airspace within the infusion bag. 10. Gently invert the infusion bag to mix the solution. Do not shake or agitate the product. After dilution, the solution will have a final concentration of 0.2 to 0.7 mg/mL of agalsidase beta. 2.5 Storage Instructions for the Reconstituted and Diluted Product Dilute the reconstituted solution without delay and use immediately. If immediate use is not possible, the reconstituted and diluted solution may be stored at 2°C to 8°C (36°F to 46°F) for up to 24 hours. 2.6 Administration Instructions The initial recommended infusion rate is 0.25 mg/min (15 mg/hour). For patients weighing: 30 kg or more, in the absence of hypersensitivity and/or infusion-associated reactions (IARs), increase the infusion rate in increments of 0.05 to 0.08 mg/min (3 to 5 mg/hour) with each subsequent infusion. The minimum infusion duration is 1.5 hours (based on individual patient tolerability) [see Dosage and Administration (2.6) ] . Less than 30 kg, the m

6 ADVERSE REACTIONS The following clinically significant adverse reactions are described elsewhere in labeling: Hypersensitivity Reactions Including Anaphylaxis [see Warnings and Precautions (5.1) ] Infusion-Associated Reactions [see Warnings and Precautions (5.2) ] Most common adverse reactions (≥20%) are: upper respiratory tract infection, chills, pyrexia, headache, cough, paresthesia, fatigue, peripheral edema, dizziness, and rash. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Genzyme at 1-800-633-1610 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 clinical trials of a drug cannot be directly compared to rates in the clinical trial of another drug and may not reflect the rates observed in patients in clinical practice. The data described below reflect exposure of 80 patients, ages 16 to 61 years, to 1 mg/kg FABRAZYME every two weeks in two separate double-blind, placebo-controlled clinical trials, for periods ranging from 1 to 35 months (mean 15.5 months). All 58 patients enrolled in one of the two studies continued into an open-label extension study of FABRAZYME treatment for up to 54 additional months. Patients were treated with antipyretics and antihistamines prior to the infusions. Most Common Adverse Reactions Table 2 enumerates adverse reactions that occurred during the double-blind treatment periods of the two placebo-controlled trials (Study 1 and Study 2) [see Clinical Studies (14) ] . The most common adverse reactions reported with FABRAZYME were infusion-associated reactions, (FABRAZYME 59% vs placebo 27%) some of which were severe (FABRAZYME 5.0% vs placebo 1.7%). Infusion-associated reactions are defined as adverse reactions occurring on the same day as the infusion. Common adverse reactions which occurred in ≥20% of patients treated with FABRAZYME and >2.5% compared to placebo are: upper respiratory tract infection, chills, pyrexia, headache, cough, paresthesia, fatigue, peripheral edema, dizziness and rash. Table 2: Summary of Common Adverse Reactions Reported at rate of at least 5% in FABRAZYME-treated patients and greater than 2.5% compared to placebo-treated patients. in Clinical Trials (Study 1 and 2) of Patients with Fabry Disease Adverse Reaction FABRAZYME (n=80) % Placebo (n=60) % Upper respiratory tract infection Includes reports of upper respiratory infection, nasal congestion, sinusitis, respiratory tract congestion, and pharyngitis. 53 42 Chills Includes reports of chills and feeling cold. 49 13 Pyrexia 39 22 Headache 39 28 Cough 33 25 Paresthesia 31 18 Fatigue 24 17 Peripheral edema 21 7 Dizziness 21 8 Rash 20 10 Pain in extremity 19 8 Myalgia Includes reports of myalgia and muscle spasms. 18 7 Lower respiratory tract infection 18 7 Pain 16 13 Back pain 16 10 Hypertension 14 5 Pruritus 10 3 Tachycardia 9 3 Excoriation 9 2 Increased blood creatinine 9 5 Tinnitus 8 3 Dyspnea 8 2 Fall 6 3 Burning sensation 6 0 Anxiety 6 3 Depression 6 2 Wheezing 6 0 Hypoacusis 5 0 Chest discomfort 5 2 Fungal infection 5 0 Viral infection 5 0 Hot flush 5 0 Most infusion-associated reactions requiring intervention were ameliorated with slowing of the infusion rate, temporarily stopping the infusion, and/or administration of antipyretics, antihistamines, or steroids. Adverse Reactions in Pediatric Patients In Study 3, the safety profile of FABRAZYME in pediatric Fabry disease patients, ages 8 to 16 years, was similar to that seen in adults. The most common adverse reactions (>20%) were headache, abdominal pain, pharyngitis, fever, nausea, vomiting, rhinitis, diarrhea, arthralgia, and dizziness [see Use in Specific Populations (8.4) and Clinical Studies (14) ] . 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. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay 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 to FABRAZYME in the studies described below with the incidence of antibodies in other studies or to other agalsidase beta products may be misleading. Patients with classic Fabry disease in Study 1, Study 2, and extension studies were tested at multiple time points for antibodies to agalsidase beta during the 55 to 58-month period. Approximately 83% (110 of 133) of adult patients receiving agalsidase beta developed antibodies; 77% (102/133) of patients developed neutralizing antibody (NAb) that inhibited in vitro agalsidase beta catalytic activity, which declined over time, and 6% (8/133) of patients developed NAb that inhibited cellular uptake. In pediatric patients with Fabry disea