A Prospective Observational Sub-Study of the Global Hypophosphatasia Registry to Describe the Potential Risk of Immune-Mediated Loss of Pharmacological Effect of Asfotase Alfa in Participants With Hypophosphatasia

What this Trial Is About

Researchers are following participants with pediatric-onset hypophosphatasia (HPP), a rare bone disease that begins in childhood, to understand how the treatment asfotase alfa works over time. This observational sub-study will track patients at various sites in the United States and possibly other countries for at least five years, focusing on how the body responds to the treatment and any immune-related issues that may affect its effectiveness. All participants will receive asfotase alfa given under standard care, typically as subcutaneous injections. Younger children under 2 years old are recommended to have clinic visits about every three months until they turn two, then about every six months afterward. The study monitors biochemical, clinical, imaging (if needed), and quality of life outcomes related to HPP to understand the long-term effects of treatment. Participants will be regularly evaluated over a minimum five-year period, including assessments by their treating physicians to detect any loss of treatment effectiveness or serious immune-related side effects. Data collection will include clinical exams, laboratory tests, functional assessments, and quality of life questionnaires. The study aims to gather detailed information about treatment outcomes and safety in real-world settings over time.

A Prospective Sub-Study of the Global Hypophosphatasia Registry