Asfotase alfa Brand Name– Strensiq
What is Asfotase alfa
Asfotase alfa is an enzyme replacement therapy for treatment of perinatal/infantile- and juvenile-onset hypophosphatasia (HPP). HPP is caused by mutations in the tissue nonspecific alkaline phosphatase (TNSALP) enzyme, which is encoded by the alkaline phosphatase (ALP) gene.
TNSALP is responsible for formation of an essential mineral in normal bone; deficient TNSALP results in defective bone mineralization that can result in bone and skeletal system abnormalities, as well as systemic complications such as muscle weakness and respiratory failure.
HPP is a genetic, chronic, progressive, and potentially life-threatening metabolic disease that affects less than 20 patients per one million in the general population.
Asfotase alfa is produced by genetically engineered Chinese hamster ovary cells and replaces the deficient TNSALP in patients with HPP.
Asfotase alfa was evaluated in four prospective, open-label studies involving 99 patients (ages 1 day to 58 years) with perinatal, infantile-, or juvenile-onset HPP (who received treatment for up to 6.5 years); data was also included from two retrospective natural history studies used as control cohorts.
In patients with perinatal/infantile-onset HPP, treatment with asfotase alfa improved overall survival and ventilator-free survival. At 48 weeks, 97% of treated patients were alive compared to 42% for the historical control patients.
Patients with juvenile-onset HPP treated with asfotase alfa showed improvements in mobility, growth, and bone health compared to untreated historical control patients.
All treated patients had improvements in low weight or short stature compared to approximately 20% of control patients that had growth delays over time.
Juvenile-onset HPP patients also showed improvements in bone mineralization and demonstrated healing of rickets on x-rays while some of the control patients showed increasing signs of rickets over time.
Because ectopic calcification of the eyes and kidneys can occur, ophthalmologic examinations and renal ultrasounds are recommended at baseline and periodically during treatment.
Asfotase alfa was approved by the FDA in October 2015.
- hypophosphatasia (HPP)
- anaphylactoid reactions
- antibody formation
- ectopic calcification
- injection site reaction
- skin hypopigmentation
- ophthalmologic exam
- serum creatinine/BUN
- laboratory test interference
- serious hypersensitivity reactions or anaphylaxis
There are no drug interactions associated with Asfotase alfa products.