Completed

PaTHwayTransCon PTH for Hypoparathyroidism Treatment

Study Aim

This phase 3 study aims to evaluate the effectiveness of TransCon PTH treatment in managing hypoparathyroidism by measuring the percentage of participants who achieve normal serum calcium levels, independence from active vitamin D and therapeutic doses of calcium, and no increase in prescribed study drug within 4 weeks prior to the 26-week visit.

What is being tested

TransCon PTH

+ Placebo

Combination Product

Who is being recruted

Endocrine System Diseases

+ Hypoparathyroidism

+ Parathyroid Diseases

Over 18 Years

+39 Eligibility Criteria

See all eligibility criteria

How is the trial designed

Treatment Study

Placebo-ControlledPhase 3

Interventional

Study Start: February 2021

See protocol details

Summary

Principal SponsorAscendis Pharma Bone Diseases A/S

Last updated: February 10, 2026

Sourced from a government-validated database.Claim as a partner

Study start date: February 16, 2021

Actual date on which the first participant was enrolled.

The PaTHway Trial is a global study exploring the safety, tolerability, and effectiveness of a drug called TransCon PTH in adults with hypoparathyroidism, a condition where the body produces insufficient parathyroid hormone. The trial is in its third phase and aims to address this unmet need by evaluating TransCon PTH as a potential treatment. This study is significant as it could pave the way for improved care and management of hypoparathyroidism. During the first 26 weeks, participants are randomly split into two groups. One group receives TransCon PTH, while the other receives a placebo. Both are administered daily as a subcutaneous injection using a pre-filled pen, starting with a dose of 18 mcg/day. This dose can be gradually increased in increments of 3 mcg/day to find the optimal dose for each individual. Neither the participants nor their doctors know who is receiving the drug or the placebo. After 26 weeks, all participants receive TransCon PTH, with the dose adjusted to their individual needs, as part of a long-term extension study.

Official TitlePaTHway TRIAL: A Phase 3, Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Trial, With an Open-Label Extension, Investigating the Safety, Tolerability and Efficacy of TransCon PTH Administered Subcutaneously Daily in Adults With Hypoparathyroidism

NCT04701203

Principal SponsorAscendis Pharma Bone Diseases A/S

Last updated: February 10, 2026

Sourced from a government-validated database.Claim as a partner

Protocol

This section provides details of the study plan, including how the study is designed and what the study is measuring.

Design Details

84 patients to be enrolled

Total number of participants that the clinical trial aims to recruit.

Treatment Study

These studies test new ways to treat a disease, condition, or health issue. The goal is to see if a new drug, therapy, or approach works better or has fewer side effects than existing options.

Eligibility

Researchers look for people who fit a certain description, called eligibility criteria: person's general health condition or prior treatments.

Conditions

Criteria

Any sex

Biological sex of participants that are eligible to enroll.

Over 18 Years

Range of ages for which participants are eligible to join.

Healthy volunteers not allowed

If individuals who are healthy and do not have the condition being studied can participate.

Conditions

Pathology

Endocrine System DiseasesHypoparathyroidismParathyroid Diseases

Criteria

17 inclusion criteria required to participate

Males and females, ≥18 years of age

Optimization of supplements prior to randomization to achieve the target serum levels of:

Able to perform daily subcutaneous self-injections of study drug (or have a designee to perform injections) via a pre-filled injection pen

Thyroid-stimulating hormone (TSH) within normal laboratory limits within the 6 weeks prior to Visit 1; if on suppressive therapy for a history of thyroid cancer, TSH level must be ≥0.2 mIU/mL

Show More Criteria

22 exclusion criteria prevent from participating

Use of other drugs known to influence calcium and bone metabolism, such as calcitonin, fluoride tablets (>0.5 mg/day), strontium, or cinacalcet hydrochloride, within 12 weeks prior to Screening

Use of osteoporosis therapies known to influence calcium and bone metabolism, i.e., bisphosphonate (oral or intravenous [IV]), denosumab, raloxifene, or romosozumab therapies within 2 years prior to Screening

Non-hypocalcemic seizure disorder with a history of a seizure within 26 weeks prior to Screening

Increased risk for osteosarcoma, such as those with Paget's disease of bone or unexplained elevations of alkaline phosphatase, hereditary disorders predisposing to osteosarcoma, or with a prior history of substantial external beam or implant radiation therapy involving the skeleton

Show More Criteria

Study Plan

Find out more about all the medication administered in this study, their detailed description and what they involve.

Treatment Groups

Study Objectives

2 intervention groups are designated in this study

50% chance of being blinded to the placebo group

Treatment Groups

Group I

Experimental

TransCon PTH at a starting dose of 18 mcg delivered once daily by subcutaneous injection and titrated to an optimal dose

Group II

Placebo

Placebo for TransCon PTH delivered once daily by subcutaneous injection

Study Objectives

Primary Objectives

Secondary Objectives

Study Centers

These are the hospitals, clinics, or research facilities where the trial is being conducted. You can find the location closest to you and its status.

This study has 21 locations

Suspended

Ascendis Pharma Investigational Site

San Francisco, United StatesOpen Ascendis Pharma Investigational Site in Google Maps

Suspended

Ascendis Pharma Investigational Site

Chicago, United States

Suspended

Ascendis Pharma Investigational Site

Rochester, United States

Suspended

Ascendis Pharma Investigational Site

Reno, United States

Completed21 Study Centers