XENPOZYME

5 WARNINGS AND PRECAUTIONS Infusion-Associated Reactions (IARs): If severe IARs occur, discontinue XENPOZYME and initiate appropriate medical treatment. ( 5.2 ) Elevated Transaminases: Assess ALT and AST within one month prior to initiation of XENPOZYME, within 72 hours prior to any infusion during dose escalation, or prior to the next scheduled XENPOZYME infusion upon resuming treatment following a missed dose. ( 5.3 ) Risk of Fetal Malformations During Dosage Initiation or Escalation in Pregnancy: XENPOZYME dosage initiation or escalation, at any time during pregnancy, is not recommended as it may lead to elevated sphingomyelin metabolite levels that may increase the risk of fetal malformations. Advise females of reproductive potential to use effective contraception during treatment and for 14 days after the last dose if XENPOZYME is discontinued. ( 5.4 , 8.1 , 8.3 ) 5.1 Hypersensitivity Reactions Including Anaphylaxis Life-threatening hypersensitivity reactions, including anaphylaxis, have been reported in olipudase alfa-treated patients. One 18-month-old XENPOZYME-treated patient experienced an anaphylactic reaction during the sixth infusion in the dose escalation period in Trial 2 [see Adverse Reactions (6.1) ] . Additionally, a 16-month-old patient with ASMD type A, treated with a version of olipudase alfa manufactured from a different process, experienced two anaphylactic reactions during the fifth and sixth infusions in the dose escalation period; the patient received an immune tolerance induction therapy prior to treatment. In both of these pediatric patients with anaphylaxis, anti-olipudase alfa-rpcp IgE (IgE ADA) and IgG (IgG ADA) antibodies were detected [see Adverse Reactions (6.1) and Clinical Pharmacology (12.6) ] . Hypersensitivity reactions that were mild to moderate in severity occurred in 10 (33%) XENPOZYME-treated adult patients and 4 (50%) XENPOZYME-treated pediatric patients in clinical trials. Hypersensitivity reactions in adults included urticaria, pruritus, erythema, rash, rash erythematous, eczema, angioedema, and erythema nodosum. Hypersensitivity reactions in pediatric patients included urticaria, pruritus, rash, erythema, and localized edema [see Adverse Reactions (6) ] . Prior to XENPOZYME administration, consider premedicating with antihistamines, antipyretics, and/or corticosteroids. Appropriate medical monitoring and support measures, including cardiopulmonary resuscitation equipment, should be readily available during XENPOZYME administration. If a severe hypersensitivity reaction (e.g., anaphylaxis) occurs, discontinue XENPOZYME immediately and initiate appropriate medical treatment. Consider the risks and benefits of re-administering XENPOZYME following a severe hypersensitivity reaction (including anaphylaxis). One patient has been rechallenged using slower infusion rates at a dosage lower than the recommended dosage. In patients with a severe hypersensitivity reaction, a tailored desensitization procedure to XENPOZYME may be considered. If the decision is made to readminister XENPOZYME, ensure the patient tolerates the infusion. If the patient tolerates the infusion, the dosage (dose and/or the rate) may be increased to reach the recommended dosage. Consider testing for IgE ADA in XENPOZYME-treated patients who experienced severe hypersensitivity reactions, including anaphylaxis [ see Adverse Reactions (6.1) ]. Testing for antibodies against olipudase alfa-rpcp are available through Genzyme Corporation (at 1-800-745-4447). Consider other clinical laboratory testing such as serum tryptase and complement activation in patients who experience anaphylaxis. If a mild or moderate hypersensitivity reaction occurs, consider temporarily holding the infusion, slowing the infusion rate, and/or reducing the XENPOZYME dose [see Dosage and Administration (2.5) ] . 5.2 Infusion-Associated Reactions IARs occurred in approximately 75% of pediatric and 50% of adult XENPOZYME-treated patients in the clinical trials; a severe IAR occurred in one (12.5%) of the pediatric patients. The most frequent IARs in: ≥10% of adult patients were headache, pruritus, vomiting, and urticaria >20% of pediatric patients were urticaria, erythema, headache, nausea, pyrexia, and vomiting Acute phase reaction (APR), an acute inflammatory response accompanied by elevations in inflammatory serum protein concentrations, was observed in one XENPOZYME-treated adult and one XENPOZYME-treated pediatric patient. Most of the APRs occurred at 48 hours post infusion during the dose escalation period. Elevations of C-reactive protein, calcitonin, and IL-6, and reduction of serum iron were observed. The most common clinical symptoms associated with APRs were pyrexia, vomiting, and diarrhea. Acute phase reactions were managed similar to other IARs. In the postmarketing setting, 24 hours after receiving XENPOZYME at a higher than recommended initial dose, a 2-year-old male patient with ASMD, experienced fever, respiratory distress, hypotension, and death [see Overdosage (10) ] . Prior to XENPOZYME administration, consider pre-medicating with antihistamines, antipyretics, and/or corticosteroids to reduce the risk of infusion-associated reactions (IARs). However, IARs may still occur in patients after receiving pre-treatment. Follow the dose escalation regimen to minimize IARs [see Dosage & Administration (2.2 & 2.3) ] . If a severe IAR occurs, discontinue XENPOZYME immediately and initiate appropriate medical treatment. Consider the risks and benefits of re-administering XENPOZYME following a severe IAR. One patient has been rechallenged using slower infusion rates at a dosage lower than the recommended dosage. If the patient tolerates the infusion, the dosage (dose and/or the rate) may be increased to reach the recommended dosage. If a mild or moderate IAR occurs, consider temporarily holding the infusion, slowing the infusion rate, and/or reducing the XENPOZYME dosage [see Dosage and Administration (2.5) ] . 5.3 Elevated Transaminase Levels XENPOZYME may be associated with elevated transaminases (ALT, AST, or both) within 24 to 48 hours after infusion. Elevated transaminase levels were reported in 4 (13%) XENPOZYME-treated adults and 1 (13%) XENPOZYME-treated pediatric patient during the dose escalation phase in clinical trials. At the time of the next scheduled infusion, these elevated transaminase levels generally returned to levels observed prior to the XENPOZYME infusion [see Adverse Reactions (6.1) ] . To manage the risk of elevated transaminase levels, assess ALT and AST within one month prior to initiation of XENPOZYME, within 72 hours prior to any infusion during dose escalation, which includes the first 3 mg/kg dose outlined in Tables 1 and 2, or prior to the next scheduled XENPOZYME infusion upon resuming treatment following a missed dose. If either the baseline or pre-infusion transaminase level (during the dose escalation phase) is >2 times the ULN, repeat transaminase levels within 72 hours after the end of the infusion. If the pre-infusion transaminase levels are elevated above baseline and >2 times the ULN prior to the next scheduled administration, the XENPOZYME dose can be reduced (repeat prior lower dose or reduce the dose) or XENPOZYME can be temporarily withheld until the liver transaminases return to the patient's baseline value. Upon reaching the recommended maintenance dose, transaminase testing is recommended to be continued as part of routine clinical management of ASMD. 5.4 Risk of Fetal Malformations During Dosage Initiation or Escalation in Pregnancy There is no evidence that olipudase alfa-rpcp crosses the human placenta. However, published literature reports that early embryonic exposure to a metabolite of sphingomyelin (ceramide) or the S1P receptor modulator fingolimod can produce exencephaly in chicks and mice, respectively. In animal reproduction studies, exencephaly, a neural tube defect occurring in the first trimester of pregnancy, was observed in mouse fetuses at exposures less than the exposure at the maximum recommended human dose of olipudase alfa-rpcp. XENPOZYME dosage initiation or escalation, at any time during pregnancy, is not recommended as it may lead to elevated sphingomyelin metabolite levels that may increase the risk of fetal malformations [see Use in Specific Population (8.1) , Clinical Pharmacology (12.2) ] . The decision to continue or discontinue XENPOZYME maintenance dosing in pregnancy should consider the female's need for XENPOZYME, the potential drug-related risks to the fetus, and the potential adverse outcomes from untreated maternal ASMD disease. Verify the pregnancy status in females of reproductive potential prior to initiating XENPOZYME treatment. Advise females of reproductive potential to use effective contraception during treatment and for 14 days after the last dose if XENPOZYME is discontinued [see Use in Specific Populations (8.3) ] .