ALXN1850-HPP-303 - Chestnut - Phase 3 - ALXN1850 vs Asfotase Alfa in HPP Paediatric Patients
Research type
Research Study
Full title
A Phase 3, Randomized, Open-label, Parallel-arm, Active-controlled, Multicenter Study to Evaluate Safety and Efficacy of ALXN1850 Versus Asfotase Alfa Administered Subcutaneously in Pediatric Participants (2 to < 12 years of age) with Hypophosphatasia (HPP) Previously Treated with Asfotase Alfa.
IRAS ID
1008902
Contact name
Per Gustafsson
Contact email
Sponsor organisation
Alexion Pharmaceuticals, Inc.
Clinicaltrials.gov Identifier
Research summary
The purpose of this open label, phase 3 study is to assess if the study drug (ALXN1850) works better compared to asfotase alfa (Strensiq®) when given to paediatric participants (2 to less than 12 years of age) with hypophosphatasia (HPP) who have previously been treated with asfotase alfa. The study aims to assess, but not limited to, the following:
- Side effects of ALXN1850, how often they happen, and the severity of side effects compared to Strensiq®.
-How well ALXN1850 works by using x-ray imaging to evaluate radiographic measures (Radiographic Global Impression of Change (RGI-C) & Rickets Severity Score (RSS).
- Assess functional outcomes.
- What the body does to ALXN1850 (pharmacokinetics) and what ALXN1850 does to the body (pharmacodynamics),
- Evaluate health quality of life outcomes based on health questionnaire completion by the participants/caregiver and if ALXN1850 triggers an immune response.
Strensiq® is the only approved treatment for HPP for paediatric onset patients. ALXN1850 has been developed to address the unmet needs of Strensiq®, which are to increase drug exposure & make enzyme activity more efficient, thereby enabling study drug dosing at lower volumes & less frequently.
This study consists of 4 phases: Screening, Randomised Evaluation period (REP), Open label Extension & Safety Follow Up. Participants who meet the study eligibility criteria will have a 50% chance of receiving ALXN1850 or Strensiq®. During REP, all participants will be randomly assigned to receive study intervention (ALXN1850 or Strensiq®) starting on Day 1 and thereafter for a total of 24 weeks. The ALXN1850 group will receive a body weight-based dose of ALXN1850 every 2 weeks via subcutaneous (SC) injection. The Strensiq® group will receive 6 mg/kg per week of Strensiq® via SC injection given as 2 mg/kg 3 times per week or 1mg/kg 6 times per week. The total study duration is 164 weeks. Approx. 40 participants worldwide will be enrolled in this study.REC name
South Central - Berkshire Research Ethics Committee
REC reference
23/SC/0430
Date of REC Opinion
29 Jan 2024
REC opinion
Further Information Favourable Opinion