Phase 3 Study of ALXN1850 Versus Placebo in Adolescent and Adult Participants With HPP Who Have Not Previously Been Treated With Asfotase Alfa
NCT ID: NCT06079281
Last Updated: 2025-11-13
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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ACTIVE_NOT_RECRUITING
PHASE3
124 participants
INTERVENTIONAL
2024-01-03
2028-03-29
Brief Summary
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Detailed Description
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Conditions
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Keywords
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Study Design
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RANDOMIZED
PARALLEL
TREATMENT
QUADRUPLE
Study Groups
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Placebo Group
During the Randomized Evaluation Period, the placebo group will receive placebo on Day 1, followed by once every 2 weeks (q2w) via SC injection for 24 weeks. Participants will enter the OLE Period and receive bodyweight dependent doses of either 20mg, 35mg, or 50mg of ALXN1850 and continue q2w dosing with ALXN1850 for up to 132 weeks.
Placebo
Placebo will be administered via SC injection.
ALXN1850 Group
Starting at Day 1 of the Randomized Evaluation Period, the ALXN1850 group will receive bodyweight dependent doses of either 20mg, 35mg or 50mg of ALXN1850 once q2w via SC injection, for 24 weeks. Participants will enter the OLE Period and continue q2w dosing with ALXN1850 for up to 132 weeks.
ALXN1850
ALXN1850 will be administered via subcutaneous (SC) injection.
Placebo
Placebo will be administered via SC injection.
Interventions
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ALXN1850
ALXN1850 will be administered via subcutaneous (SC) injection.
Placebo
Placebo will be administered via SC injection.
Eligibility Criteria
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Inclusion Criteria
* 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) or ISO 15189 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)
* Must meet 1 of the following criteria without a probably cause other than HPP:
1. Serum ALP activity below the age- and sex-adjusted normal range during the screening period as measured by the Central Laboratory
2. Two documented serum ALP activity results, at least 15 days apart, below the age- and sex-adjusted local laboratory normal range during the 24 months before the Day 1 Visit. Note: Local laboratories need to be CLIA or ISO 15189 certified, or have other local equivalent laboratory certification with Alexion's approval.
* Two separate 6MWTs at below 85% of the predicted distance (for age, sex, weight, and height) during the Screening Period without a probable cause other than HPP
Exclusion Criteria
* 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 (Table 9)
12 Years
130 Years
ALL
No
Sponsors
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Alexion Pharmaceuticals, Inc.
INDUSTRY
Responsible Party
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Locations
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Research Site
Indianapolis, Indiana, United States
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Garden City, New York, United States
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Durham, North Carolina, United States
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Columbus, Ohio, United States
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Nashville, Tennessee, United States
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Ciudad de Buenos Aires, , Argentina
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Clayton, , Australia
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Herston, , Australia
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Parkville, , Australia
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St Leonards, , Australia
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Belo Horizonte, , Brazil
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Brasília, , Brazil
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Recife, , Brazil
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Salvador, , Brazil
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São Paulo, , Brazil
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São Paulo, , Brazil
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Calgary, Alberta, Canada
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Edmonton, Alberta, Canada
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Winnepeg, Manitoba, Canada
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Oakville, Ontario, Canada
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Trois-Rivières, Quebec, Canada
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Beijing, , China
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Beijing, , China
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Changsha, , China
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Chengdu, , China
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Nanchang, , China
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Qingdao, , China
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Shanghai, , China
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Shenzhen, , China
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Paris, , France
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Poitiers, , France
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Bad Reichenhall, , Germany
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Berlin, , Germany
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Bonn, , Germany
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Hamburg, , Germany
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Würzburg, , Germany
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Ashkelon, , Israel
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Ramat Gan, , Israel
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Florence, , Italy
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Milan, , Italy
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Milan, , Italy
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Padua, , Italy
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Pisa, , Italy
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San Giovanni Rotondo, , Italy
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Verona, , Italy
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Hiroshima, , Japan
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Iizuka-shi, , Japan
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Osaka, , Japan
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Sapporo, , Japan
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Yaizu-shi, , Japan
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Lodz, , Poland
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Seoul, , South Korea
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Seoul, , South Korea
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Suwon, , South Korea
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Barcelona, , Spain
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Granada, , Spain
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Madrid, , Spain
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San Cristóbal de La Laguna, , Spain
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Santander, , Spain
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Vitoria-Gasteiz, , Spain
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Taipei, , Taiwan
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Taoyuan District, , Taiwan
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Ankara, , Turkey (Türkiye)
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Erzurum, , Turkey (Türkiye)
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London, , United Kingdom
Countries
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Related Links
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Routing the applicable forms for final approval prior to submission by the CTIS Expert
Other Identifiers
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ALXN1850-HPP-301
Identifier Type: OTHER
Identifier Source: secondary_id
D8590C00002
Identifier Type: -
Identifier Source: org_study_id