NCT05778071

Evaluation of the Safety and Efficacy of Eneboparatide (AZP-3601) in Patients With Chronic Hypoparathyroidism

A Phase 3 Multicenter, Randomized, Placebo-controlled, Double-blind Study to Evaluate the Efficacy and Safety of Eneboparatide (AZP-3601), a Parathyroid Hormone Receptor Agonist, in Patients With Chronic Hypoparathyroidism (CALYPSO)

• Status: Active Not Recruiting
• Phase: Phase 3
• Study type: Interventional
• Enrollment: 165 (estimated)
• Sponsor: Alexion Pharmaceuticals, Inc. · Industry
• Sex: All
• Age: 18 Years – 80 Years
• Healthy volunteers: Not accepted

Summary

This study is investigating the safety and efficacy of eneboparatide (AZP-3601) in patients with chronic hypoparathyroidism (cHP). During the first 24 weeks of the trial, participants will be randomized to receive eneboparatide or placebo. Study treatment is blinded: patients and doctors will not know which group each patient has been randomized to. All patients will start with a fixed dose of study treatment (eneboparatide or placebo), administered subcutaneously with a pre-filled pen. Study treatment will be individually titrated. After completion of the first 24 weeks, patients will be treated in the open label extension part of the study for 132 weeks. During this phase, all patients (including patients that were in the placebo group) will receive eneboparatide.

Conditions

• Chronic Hypoparathyroidism
• Endocrine System Diseases
• Parathyroid Diseases

Interventions

Type	Name	Description
COMBINATION_PRODUCT	eneboparatide	Supplied as a solution (concentration of 250 mcg/mL or 500 mcg/mL) in single-patient-use prefilled pens
COMBINATION_PRODUCT	Placebo	Placebo is supplied as a solution (containing the excipient solution for eneboparatide) in single-patient-use prefilled pens

Timeline

• Start date: 2023-06-07
• Primary completion: 2024-11-15
• Completion: 2027-06-16
• First posted: 2023-03-21
• Last updated: 2025-09-29

Locations

54 sites across 13 countries: United States, Canada, Denmark, France, Germany, Hungary, Italy, Japan, Netherlands, Poland, Portugal, Spain, United Kingdom

Regulatory

• FDA-regulated drug study