Phase 3 Study of ALXN1850 in Pediatric Participants with HPP Previously Treated with Asfotase Alfa

Phase 1

• Conditions: Hypophosphatasia; Therapeutic area: Diseases [C] - Musculoskeletal Diseases [C05]

• Registration Number: CTIS2023-505674-15-00
• Lead Sponsor: Alexion Pharmaceuticals Inc.

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study Start: 2023-12-12
• Last Update Posted: 22 July 2024

Recruitment & Eligibility

• Status: ot Recruiting
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

Participant must be = 2 and < 12 years of age at Day 1., Diagnosis of HPP documented in the medical records., Presence of open growth plates by X-ray during Screening Period., Tanner stage 2 or less during the Screening Period., Must have been treated with 6 mg/kg/week of asfotase alfa via SC injection administered as either 2 mg/kg 3 times per week or 1 mg/kg 6 times per week for = 6 months before Day 1., Female participants of childbearing potential and male participants must follow contraception requirements and guidance as defined in the protocol., The participant’s legal guardian must be willing and able to provide written informed consent (as defined in the protocol) and the participant must be willing to give written informed assent (if applicable as determined by the central or local Institutional Review Board [IRB]/Institutional [or Independent] Ethics Committee [IEC]). Written informed consent/assent includes compliance with the requirements and restrictions listed in the informed consent form (ICF) and in this protocol.

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., Received IV bisphosphonate within 12 months before Day 1., Received a parathyroid hormone (PTH)-related protein analog (eg, abaloparatide) or PTH analog (eg, teriparatide) within 2 weeks before Day 1., Received strontium within 6 months before Day 1., Received sclerostin inhibitors within 6 months before Day 1., Received growth hormone therapy within 6 months before Day 1., Received estrogen agonist/antagonist/inhibitor within 2 months before Day 1 unless used as contraception or for treatment of dysmenorrhea., Received a RANKL inhibitor within 6 months before Day 1., Participation in any other clinical study involving an investigational study intervention within 30 days before initiation of the first dose of study intervention. Participants involved in interventional studies are not eligible unless the time since last treatment has exceeded 30 days or 5 half-lives of the study intervention, whichever is longer., Corrected calcium levels (adjusted for albumin) below age-adjusted normal range during Screening., Serum phosphorus levels below the age-adjusted normal range during Screening., Diagnosis of primary or secondary hyperparathyroidism., Evidence of a treatable form of rickets (eg, vitamin D deficiency) other than HPP during Screening., Serum 25-hydroxy (25-OH) vitamin D below 20 ng/mL during Screening., PTH > upper limit of normal (ULN) of the laboratory reference range during Screening., Participants who are unwilling to undergo genetic testing for the ALPL gene., Participants who are pregnant, planning to become pregnant, or breastfeeding during the course of the study., Investigational site personnel involved directly in the study and/or their immediate families. Immediate family is defined as a spouse, parent, child, or sibling, whether biological or legally adopted., 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 asfotase alfa or ALXN1850., Body weight < 10 kg during the Screening Period., Received vitamin B6 (including vitamin supplements that contain vitamin B6) within 6 weeks before Day 1., Received oral bisphosphonate within 6 months before Day 1.

Study & Design

• Study Type: Interventional clinical trial of medicinal product
• Study Design: Not specified