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.
The most serious adverse reactions reported with ALDURAZYME treatment during clinical trials were anaphylactic and hypersensitivity reactions. Most adverse reactions reported in clinical trials were considered disease-related and unrelated to study drug. The most common adverse reactions were infusion reactions. The frequency of infusion reactions decreased over time with continued use of ALDURAZYME, and the majority of reactions were classified as being mild to moderate in severity. Most infusion reactions requiring intervention were ameliorated with slowing of the infusion rate, temporarily stopping the infusion, with or without administering additional treatments including antihistamines, antipyretics, or both.
Clinical Trials in Patients 6 Years and Older
A 26-week, double-blind, placebo-controlled clinical study (Study 1) of ALDURAZYME was conducted in 45 patients with MPS I, ages 6 to 43 years old, gender evenly distributed (N=23 females and 22 males). Of these 45 patients, 1 was clinically assessed as having Hurler form, 37 Hurler-Scheie, and 7 Scheie. Patients were randomized to receive either 0.58 mg/kg intravenously of ALDURAZYME per week for 26 weeks or placebo. All patients were treated with antipyretics and antihistamines prior to the infusions. Infusion reactions were reported in 32% (7 of 22) of ALDURAZYME-treated patients. The most commonly reported infusion reactions regardless of treatment group were flushing, pyrexia, headache, and rash. Flushing occurred in 5 patients (23%) receiving ALDURAZYME; the other reactions were less frequent. Less common infusion reactions included angioedema (including face edema), hypotension, paresthesia, feeling hot, hyperhidrosis, tachycardia, vomiting, back pain, and cough. Other reported adverse reactions included bronchospasm, dyspnea, urticaria and pruritus.
Table 3 enumerates adverse reactions and selected laboratory abnormalities that occurred during the placebo-controlled study (Study 1) that were reported in at least 2 patients more in the ALDURAZYME group than in the placebo group.
Table 3: Summary of Adverse Reactions that Occurred in 2 Patients More in the ALDURAZYME® Group than in the Placebo Group in the 26-Week Placebo-controlled Study (Study 1) MedDRA System Organ Class (SOC) MedDRA Preferred Term | (N=22) ALDURAZYME n (%) | (N=23) Placebo n (%) |
| Blood and lymphatic system disorders | | |
| Thrombocytopenia | 2 (9) | 0 |
| Eye disorders | | |
| Corneal opacity | 2 (9) | 0 |
| General disorders and administration site conditions | | |
| Chest pain | 2 (9) | 0 |
| Face edema | 2 (9) | 0 |
| Gravitational edema | 2 (9) | 0 |
| Injection site pain | 2 (9) | 0 |
| Injection site reaction | 4 (18) | 2 (9) |
| Hepatobiliary disorders | | |
| Hyperbilirubinemia | 2 (9) | 0 |
| Infections and infestations | | |
| Abscess | 2 (9) | 0 |
| Upper respiratory tract infection | 7 (32) | 4 (17) |
| Nervous system disorders | | |
| Hyperreflexia | 3 (14) | 0 |
| Paresthesia | 3 (14) | 1 (4) |
| Skin and subcutaneous tissue disorders | | |
| Rash | 8 (36) | 5 (22) |
| Vascular disorders | | |
| Hypotension | 2 (9) | 0 |
| Poor venous access | 3 (14) | 0 |
All 45 patients who completed the placebo-controlled study (Study 1) continued treatment in an open-label, uncontrolled extension study (Study 2). All patients received ALDURAZYME 0.58 mg/kg of body weight once weekly for up to 182 weeks. The most serious adverse reactions reported with ALDURAZYME infusions in Study 2 were anaphylactic and hypersensitivity reactions [see Warnings and Precautions (5)]. The most common adverse reactions requiring intervention were infusion reactions reported in 49% (22 of 45) of patients treated with ALDURAZYME. The most commonly reported infusion reactions included rash (13%), flushing (11%), pyrexia (11%), headache (9%), abdominal pain or discomfort (9%), and injection site reaction (9%). Less commonly reported infusion reactions included nausea (7%), diarrhea (7%), feeling hot or cold (7%), vomiting (4%), pruritus (4%), arthralgia (4%), and urticaria (4%). Additional common adverse reactions included back pain and musculoskeletal pain.
Clinical Trials in Patients 6 Years and Younger
Study 3 was a 52-week, open-label, uncontrolled study of 20 MPS I patients, ages 6 months to 5 years old (at enrollment). Sixteen patients were clinically assessed as having the Hurler form, and 4 had the Hurler-Scheie form. All 20 patients received ALDURAZYME at 0.58 mg/kg of body weight once weekly for 26 weeks and up to 52 weeks. All patients were treated with antipyretics and antihistamines prior to the infusions.
The most commonly reported serious adverse events (regardless of relationship) reported with ALDURAZYME infusions in Study 3 were otitis media (20%), and central venous catheterization required for ALDURAZYME infusion (15%).
The nature and severity of infusion reactions were similar between the older and less severely affected patients in Studies 1 and 2, and the younger, more severely affected patients in Study 3. The most commonly reported adverse reactions in Study 3 were infusion reactions reported in 35% (7 of 20) of patients and included pyrexia (30%), chills (20%), blood pressure increased (10%), tachycardia (10%), and oxygen saturation decreased (10%). Other commonly reported infusion reactions occurring in ≥5% of patients were pallor, tremor, respiratory distress, wheezing, crepitations (pulmonary), pruritus, and rash.