Phase 3 Study of ALXN1850 in Treatment-Naïve Pediatric Participants With HPP

Hypophosphatasia Clinical Trial

— MULBERRY  

Official title:

A Phase 3, Randomized, Double-blinded, Placebo-controlled, Multicenter Study to Evaluate Efficacy and Safety of ALXN1850 Versus Placebo Administered Subcutaneously in Pediatric (2 to < 12 Years of Age) Participants With Hypophosphatasia Who Have Not Received Previous Treatment With Asfotase Alfa

Clinical Trial Details — Status: Not yet recruiting

Administrative data

• NCT number: NCT06079359
• Other study ID #: D8590C00003
• Secondary ID: ALXN1850-HPP-305
• Status: Not yet recruiting
• Phase: Phase 3
• Start date: March 1, 2024
• Est. completion date: July 30, 2027

Study information

• Verified date: February 2024
• Source: Alexion Pharmaceuticals, Inc.
• Contact: Alexion Pharmaceuticals, Inc. (Sponsor)
• Phone: 1-855-752-2356
• Email: clinicaltrials[@]alexion.com
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The primary purpose of this study is to evaluate the efficacy of ALXN1850 versus placebo on radiographic outcomes in pediatric participants with HPP who have not previously been treated with asfotase alfa.

Recruitment information / eligibility

• Status: Not yet recruiting
• Enrollment: 30
• Est. completion date: July 30, 2027
• Est. primary completion date: May 30, 2025
• Accepts healthy volunteers: No
• Gender: All
• Age group: 2 Years to 11 Years

Eligibility

Inclusion Criteria:

• Diagnosis of HPP documented in the medical records, and the following criteria

fulfilled during the Screening Period without other probable cause than HPP:

1. Presence of HPP-related rickets on skeletal X-rays, with a minimum Rickets Severity Score (RSS) of 1.0 AND

2. Serum ALP activity below the age- and sex-adjusted normal range

• Must meet 1 of the following criteria:

1. Documented ALPL gene variant (pathogenic, likely pathogenic, or variant of unknown significance) from a Clinical Laboratory Improvement Amendments (CLIA) certified laboratory (Section 8.7)

2. Plasma PLP above the upper limit of normal (ULN) during the Screening Period (central or local laboratory results allowed per local regulations)

• Tanner stage 2 or less during the Screening Period

Exclusion Criteria:

• History or presence of cardiovascular, respiratory, hepatic, renal, gastrointestinal, endocrinological, hematological, neurological disorders, or any other disorders that are capable of significantly altering the absorption, metabolism, or elimination of drugs; constituting a risk when taking the study intervention; or interfering with the interpretation of data as determined by the Investigator
• Diagnosis of primary or secondary hyperparathyroidism
• Hypoparathyroidism, unless secondary to HPP
• Any new fracture within 12 weeks before Day 1 (excluding pseudofractures)
• Planned surgical intervention which may impact the results of study assessments (in the opinion of the Investigator) during the Randomized Evaluation Period
• History of allergy or hypersensitivity to any ingredient contained in ALXN1850 or the placebo comparator

Related Conditions & MeSH terms

• Hypophosphatasia

Intervention

Drug:
• ALXN1850
Participants will receive a ALXN1850 via subcutaneous (SC) injection.
• Placebo
Participants will receive placebo via SC injection.

Locations

Country	Name	City	State
Argentina	Research Site	Buenos Aires
Argentina	Research Site	Ciudad Autónoma de Buenos Aires
Argentina	Research Site	Mar del Plata
Argentina	Research Site	Mar del Plata
Australia	Research Site	Nedlands
Australia	Research Site	Parkville
Australia	Research Site	Westmead
Belgium	Research Site	Brussels
Brazil	Research Site	Brasilia
Brazil	Research Site	Porto Alegre
Brazil	Research Site	Recife
Brazil	Research Site	São Paulo
Canada	Research Site	Calgary	Alberta
Canada	Research Site	Edmonton	Alberta
Canada	Research Site	Ottawa	Ontario
China	Research Site	Beijing
China	Research Site	Guangzhou
China	Research Site	Shenzhen
France	Research Site	Le Kremlin Bicêtre
France	Research Site	Paris
Germany	Research Site	Homburg
Israel	Research Site	Ashkelon
Israel	Research Site	Beer Sheva
Israel	Research Site	Petach-Tikva
Israel	Research Site	Ramat Gan
Italy	Research Site	Bologna
Italy	Research Site	Genova
Italy	Research Site	Milano
Italy	Research Site	Roma
Italy	Research Site	Rome
Korea, Republic of	Research Site	Seoul
Mexico	Research Site	Campeche
Mexico	Research Site	Chihuahua
Mexico	Research Site	Ciudad de Mexico
Mexico	Research Site	Zapopan
Poland	Research Site	Kraków
Poland	Research Site	Lódz
Poland	Research Site	Warszawa
Spain	Research Site	Vitoria
Taiwan	Research Site	Taipei
Taiwan	Research Site	Taoyuan
Thailand	Research Site	Bangkok
Thailand	Research Site	Muang
Thailand	Research Site	Songkla
Turkey	Research Site	Ankara
Turkey	Research Site	Ankara
Turkey	Research Site	Bursa
Turkey	Research Site	Edirne
Turkey	Research Site	Erzurum
Turkey	Research Site	Istambul
United Kingdom	Research Site	Birmingham
United Kingdom	Research Site	Manchester
United States	Research Site	Baltimore	Maryland
United States	Research Site	Durham	North Carolina
United States	Research Site	Kansas City	Missouri
Vietnam	Research Site	Hanoi

Sponsors (1)

Lead Sponsor	Collaborator
Alexion Pharmaceuticals, Inc.

Countries where clinical trial is conducted

United States,  Vietnam,  Argentina,  Australia,  Belgium,  Brazil,  Canada,  China,  France,  Germany,  Israel,  Italy,  Korea, Republic of,  Mexico,  Poland,  Spain,  Taiwan,  Thailand,  Turkey,  United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Radiographic Global Impression of Change (RGI-C) Score at the end of the Randomized Evaluation Period (Day 169)		Day 169
Secondary	Change from Baseline in Rickets Severity Score (RSS) at the end of the Randomized Evaluation Period (Day 169)		Baseline, Day 169
Secondary	Change from Baseline in 6-Minute Walk Test (6MWT) at the end of the Randomized Evaluation Period (Day 169)		Baseline, Day 169
Secondary	Change from Baseline in Percent Predicted 6MWT at the end of the Randomized Evaluation Period (Day 169)		Baseline, Day 169
Secondary	Change from Baseline in Bruininks Oseretsky Test of Motor Proficiency, Second Edition (BOT2) Score at the end of the Randomized Evaluation Period (Day 169)		Baseline, Day 169
Secondary	Change from Baseline in Peabody Developmental Motor Scales, Third Edition (PDMS-3) Score at the end of the Randomized Evaluation Period (Day 169)		Baseline, Day 169
Secondary	RGI-C Responder at the end of the Randomized Evaluation Period (Day 169)		Day 169