gnificantly below normal, as indicated by < 10% of normal mitogen responses and circulating mononuclear cells bearing T-cell surface antigens. These parameters improved, though not always to normal, within 2 to 6 months of therapy.
INDICATIONS AND USAGE
ADAGEN® (pegademase bovine) Injection is indicated for enzyme replacement therapy for adenosine deaminase (ADA) deficiency in patients with severe combined immunodeficiency disease (SCID) who are not suitable candidates for – or who have failed – bone marrow transplantation. ADAGEN® (pegademase bovine) Injection is recommended for use in infants from birth or in children of any age at the time of diagnosis. ADAGEN® (pegademase bovine) Injection is not intended as a replacement for HLA identical bone marrow transplant therapy. ADAGEN® (pegademase bovine) Injection is also not intended to replace continued close medical supervision and the initiation of appropriate diagnostic tests and therapy (e.g., antibiotics, nutrition, oxygen, gammaglobulin) as indicated for intercurrent illnesses.
CONTRAINDICATIONS
There is no evidence to support the safety and efficacy of ADAGEN® (pegademase bovine) Injection as preparatory or support therapy for bone marrow transplantation. Since ADAGEN® (pegademase bovine) Injection is administered by intramuscular injection, it should be used with caution in patients with thrombocytopenia and should not be used if thrombocytopenia is severe.
PRECAUTIONS
General
Any laboratory or clinical indication of a decrease in potency of ADAGEN® (pegademase bovine) Injection should be reported immediately by telephone to Enzon Pharmaceuticals, Inc. Telephone 866-792-5172.
There have been no reports of hypersensitivity reactions in patients who have been treated with ADAGEN® (pegademase bovine) Injection.
One of 12 patients showed an enhanced rate of clearance of plasma ADA activity after 5 months of therapy at 15 U/kg/week. Enhanced clearance was correlated with the appearance of an antibody that directly inhibited both unmodified ADA and ADAGEN® (pegademase bovine) Injection. Subsequently, the patient was treated with twice weekly intramuscular injections at an increased dose of 20 U/kg, or a total weekly dose of 40 U/kg. No adverse effects were observed at the higher dose and effective levels of plasma ADA were restored. After 4 months, the patient returned to a weekly dosage schedule of 20 U/kg and effective plasma levels have been maintained.
Appropriate care to protect immune deficient patients should be maintained until improvement in immune function has been documented. The degree of immune function improvement may vary from patient to patient and, therefore, each patient will require appropriate care consistent with immunologic status.
Laboratory Tests
The treatment of SCID associated with ADA deficiency with ADAGEN® (pegademase bovine) Injection should be monitored by measuring plasma ADA activity and red blood cell dATP levels.
Plasma ADA activity and red cell dATP should be determined prior to treatment. Once treatment with ADAGEN® (pegademase bovine) Injection has been initiated, a desirable range of plasma ADA activity (trough level before maintenance injection) should be 15–35 μmol/hr/mL. This minimum trough level will ensure that plasma ADA activity from injection to injection is maintained above the level of tot
