Pharmacokinetics, Efficacy, and Safety of Encaleret in Pediatric Participants With Autosomal Dominant Hypocalcemia Type 1 (ADH1)

NCT ID: NCT07080385

Last Updated: 2026-01-14

Basic Information

• Recruitment Status: RECRUITING
• Clinical Phase: PHASE2/PHASE3
• Total Enrollment: 28 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2026-02-10
• Study Completion Date: 2030-12-31

Brief Summary

The overall objective of this study is to evaluate the pharmacokinetics (PK), efficacy, and safety of encaleret in pediatric participants from birth to 17 years of age with ADH1.

Conditions

Autosomal Dominant Hypocalcemia Type 1 (ADH1)

Study Design

• Allocation Method: NA
• Intervention Model: SEQUENTIAL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: NONE

Study Groups

Encaleret

Participants will receive encaleret dosing in Period 1 (6 days), Period 2 (20 weeks) and Period 3 (4 weeks). Following completion of Period 3, participants will have the option to enter a long-term extension (LTE) to continue encaleret for an additional approximately 24 months or until the sponsor decides to end the study, whichever occurs first.

Group Type: EXPERIMENTAL

Encaleret

Intervention Type: DRUG

Oral tablets, age-appropriate pediatric formulation (currently under development).

Interventions

Encaleret

Oral tablets, age-appropriate pediatric formulation (currently under development).

Intervention Type: DRUG

Eligibility Criteria

Inclusion Criteria

• Provide written informed consent (if legally permitted), or have written informed consent from a parent/legal guardian and provide assent (where required and as appropriate per local requirements)
• Have a documented pathogenic or likely pathogenic activating variant, or variant of uncertain significance of the calcium-sensing receptor (CASR), associated with biochemical findings of hypoparathyroidism at screening or a documented history of hypoparathyroidism as manifested by hypocalcemia and intact parathyroid hormone (PTH) <40 picogram per milliliter (pg/mL) (4.2 picomoles per liter [pmol/L])
• Have at least 1 symptom or sign of hypoparathyroidism at screening or a documented history of symptoms or signs of hypoparathyroidism
• Be on ADH1 treatment for at least 6 months before screening for cohorts 1 to 3, or for at least 3 months before screening for cohort 4

Exclusion Criteria

• History of thyroid or parathyroid surgery
• History of renal transplantation
• History of cancer (except thyroid cancer, basal cell skin cancer, or squamous cell skin cancer), skeletal malignancies, bone metastases, irradiation (radiotherapy) to the skeleton, chemotherapy with alkylating agents, Paget disease, fibrous dysplasia, chronic osteomyelitis, bone infarcts, benign bone tumors with curettage and bone grafts, retinoblastoma, or Li-Fraumeni syndrome within 5 years before screening
• Received any investigational medicinal product within 30 days or 5 half-lives before Day 1, whichever is longer, or is in follow-up for another interventional clinical study during screening
• Treatment with a strong P-glycoprotein (P-gp) inhibitor within 300 days before screening for amiodarone or within 30 days before screening for any other strong P-gp inhibitor
• Treatment with cardiac glycosides, or is being breastfed while the participant's nursing mother is treated with cardiac glycosides, within 30 days before screening
• Presence or history of any disease or condition (eg, drug or alcohol dependence) that would affect the participant's safety, treatment compliance, or ability to complete the study, in the opinion of the investigator

• Minimum Eligible Age: 0 Years
• Maximum Eligible Age: 17 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Calcilytix Therapeutics, Inc., a BridgeBio company

INDUSTRY

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Calcilytix Medical Director

Role: STUDY_DIRECTOR

Calcilytix Therapeutics, Inc., a BridgeBio company

Locations

The Children's Hospital of Philadelphia

Philadelphia, Pennsylvania, United States

Site Status: RECRUITING

Countries

United States

Central Contacts

Medical Information

Role: CONTACT

MedInfo@bridgebio.com

650-600-3610

Other Identifiers

CLTX-305-303

Identifier Type: -

Identifier Source: org_study_id