Asfotase Alfa (1 brand name, 1 dosage form, 1 route)
Available dosage forms: SOLUTION.
Routes of administration: INJECTION.
Brand Names
- STRENSIQ
Boxed Warning
Patients treated with enzyme replacement therapies have experienced life-threatening hypersensitivity reactions, including anaphylaxis. Anaphylaxis has occurred during the early course of enzyme replacement therapy and after extended duration of therapy. Initiate STRENSIQ under the supervision of a healthcare provider with appropriate medical monitoring and support measures. If a severe hypersensitivity reaction (e.g., anaphylaxis) occurs, discontinue STRENSIQ and immediately initiate appropriate medical treatment, including use of epinephrine. Inform patients of the symptoms of life-threatening hypersensitivity reactions, including anaphylaxis and to seek immediate medical care should symptoms occur [see Warnings and Precautions (5.1)].
Indications and Usage
STRENSIQ® is indicated for the treatment of patients with perinatal/infantile- and juvenile-onset hypophosphatasia (HPP).
Contraindications
None.
Adverse Reactions
The following adverse reactions are described below and elsewhere in the labeling: Hypersensitivity Reactions [see Warnings and Precautions (5.1)] Lipodystrophy [see Warnings and Precautions (5.2)] Ectopic Calcifications [see Warnings and Precautions (5.3)] Possible Immune-Mediated Clinical Effects [see Warnings and Precautions (5.4)]
Mechanism of Action
HPP is caused by a deficiency in TNSALP enzyme activity, which leads to elevations in several TNSALP substrates, including inorganic pyrophosphate (PPi). TNSALP is a metallo-enzyme that catalyzes the hydrolysis of phosphomonoesters with release of inorganic phosphate and alcohol. Elevated extracellular levels of PPi block hydroxyapatite crystal growth which inhibits bone mineralization and causes an accumulation of unmineralized bone matrix which manifests as rickets and bone deformation in infants and children and as osteomalacia (softening of bones) once growth plates close, along with muscle weakness. Replacement of the TNSALP enzyme upon STRENSIQ treatment reduces the enzyme substrate levels.