[7][6] The enzyme tissue non-specific alkaline phosphatase (ALP) plays a key role in creating and maintaining healthy bones, and managing calcium and phosphate in the body.
[5] In the European Union, asfotase alfa is indicated for long-term enzyme replacement therapy in people with paediatric-onset hypophosphatasia to treat the bone manifestations of the disease.
[5] The peptide part of the glycoprotein asfotase alfa consists of two identical chains of 726 amino acids each, containing (1) the catalytic domain of TNSALP, (2) the Fc region of human immunoglobulin G1, and (3) a sequence of ten L-aspartate residues at the carboxy terminus.
[15] Asfotase alfa is manufactured by Alexion Pharmaceuticals and it was granted breakthrough therapy designation by the U.S. FDA in 2015 as it is the first and only treatment for perinatal, infantile and juvenile-onset HPP.
[6] The safety and efficacy of asfotase alfa were established in 99 participants with perinatal (disease occurs in utero and is evident at birth), infantile- or juvenile-onset HPP who received treatment for up to 6.5 years during four prospective, open-label studies.
[7] Juvenile-onset participants also showed improvements in bone mineralization, as measured on a scale that evaluates the severity of rickets and other HPP-related skeletal abnormalities based on x-ray images.