PaTHway CHINA TRIAL: A Trial to Investigating the Safety, Tolerability and Efficacy of TransCon PTH in Adults With Hypoparathyroidism

NCT05387070 | Completed Phase 3

• 2 other identifiers: TCP-306CTR20212047
• Study Type: interventional
• Target: 81
• Locations: 1 country
• Sites: 1

Brief Summary

This study is limited to conduct in China only. The primary objective is to assess the treatment effect of daily TransCon PTH on serum calcium (sCa) levels within the normal range and stopping from therapeutic doses of active vitamin D (calcitriol) or active vitamin D analogue (alfacalcidol) and calcium at 26 weeks of treatment. All subjects will start with 18 mcg of study drug and will be individually and progressively titrated to an optimal dose over a 26-week double blind period, followed by an open label extension period up to 156 weeks. TransCon PTH or placebo will be administered as a subcutaneous injection using a pre-filled injection pen. Neither trial participants nor their doctors will know who has been assigned to each group. After the 26 weeks, participants will continue in the trial as part of a long-term extension study. During the extension, all participants will receive TransCon PTH, with the dose adjusted to their individual needs.

Conditions

Hypoparathyroidism; Parathyroid Hormone Deficiency; Endocrine System Diseases; Parathyroid Diseases

Keywords

Hypoparathyroidism; TransCon PTH; Parathyroid Hormone deficiency; PTH1-34

Outcome Measures

Primary Outcomes (1)

• The proportion of subjects who meet primary efficacy endpoint at 26 weeks of treatment

  The proportion of subjects with albumin-adjusted sCa within the normal range, and independence from active vitamin D, and independence from therapeutic doses of calcium (i.e., taking calcium supplements ≤600 mg/day), and no increase in prescribed study drug within 4 weeks prior to Week 26 visit

  26 weeks

Secondary Outcomes (1)

• Change from baseline in HPES Symptom - Physical Domain score

  26 weeks

Other Outcomes (4)

• Change from baseline in HPES Symptom - Cognitive Domain score

  26 weeks

• Change from baseline in HPES Impact - Physical Functioning Domain score

  26 weeks

• Change from baseline in HPES Impact - Daily Life Domain score

  26 weeks

Study Arms (2)

TransCon PTH

EXPERIMENTAL

TransCon PTH at a starting dose of 18 mcg delivered once daily by subcutaneous injection

Drug: TransCon PTH

placebo

PLACEBO COMPARATOR

Placebo for TransCon PTH at a starting dose of 18 mcg delivered once daily by subcutaneous injection

Drug: placebo

Interventions

TransCon PTH DRUG

TransCon PTH is supplied as a solution with a concentration of 0.3 mg PTH(1-34)/mL in a single-patient-use prefilled pen intended for SC injection.

TransCon PTH

placebo DRUG

Placebo is supplied as a solution containing the formulation buffer for TransCon PTH in a single-patient-use prefilled pen intended for subcutaneous injection.

placebo

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Males and females, ≥18 years of age
• Subjects with postsurgical chronic HP, or auto-immune, genetic, or idiopathic HP for at least 26 weeks. Diagnosis of HP is established based on historic hypocalcemia in the setting of inappropriately low (below the ULN of local laboratory) serum PTH levels.
• Requirement for doses of SoC (e.g., calcitriol, alfacalcidol, calcium supplements) at or above a minimum threshold:
• requirement for a dose of calcitriol ≥0.5 μg/day, or alfacalcidol ≥1.0 μg/day and (elemental) calcium ≥800 mg/day (e.g., calcium citrate, calcium carbonate etc.) for at least 12 weeks prior to Screening. In addition, the dose of calcitriol, or alfacalcidol, and calcium should be stable for at least 5 weeks prior to Screening
• Optimization of supplements prior to randomization to achieve the target serum levels of:
• (OH) vitamin D levels of 10-100 ng/mL (25-250 nmol/L) and
• Magnesium level in the normal range, or just below the normal range i.e.: ≥1.3 mg/dL (0.53 mmol/L) and
• Albumin-adjusted sCa level in the normal range, or just below the normal range, i.e.: 7.8-10.6 mg/dL (or 1.95-2.64 mmol/L)
• The subject demonstrates a 24-hour uCa excretion of ≥125 mg/24h (on a sample collected within 52 weeks prior to Screening or during the Screening Period)
• BMI 17- 40 kg/m2 at Screening
• If ≤25 years of age, radiological evidence of epiphyseal closure based on X-ray of non-dominant wrist and hand
• 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/L
• If treated with thyroid hormone replacement therapy, the dose must have been stable for at least 5 weeks prior to Screening
• eGFR ≥30 mL/min/1.73 m2 during Screening
• Able to perform daily SC self-injections of study drug (or have a designee to perform injections) via a pre-filled injection pen

You may not qualify if:

• Impaired responsiveness to PTH (pseudohypoparathyroidism) which is characterized as PTH-resistance, with elevated PTH levels in the setting of hypocalcemia
• Any disease that might affect calcium metabolism or calcium-phosphate homeostasis or PTH levels other than HP, such as active hyperthyroidism; Paget disease of bone; severe hypomagnesemia; type 1 diabetes mellitus or poorly controlled type 2 diabetes mellitus (HbA1C \>9%, documented HbA1C result drawn within 12 weeks prior to Screening is acceptable); severe and chronic liver, or renal disease; Cushing syndrome; multiple myeloma; active pancreatitis; malnutrition; rickets; recent prolonged immobility; active malignancy (other than low-risk well differentiated thyroid cancer or non-melanoma skin cancer); active hyperparathyroidism; parathyroid carcinoma within 5 years prior to Screening; acromegaly;or multiple endocrine neoplasia
• High risk thyroid cancer within 2 years, requiring suppression of TSH \<0.2 mIU/L
• Long term use of loop diuretics, phosphate binders (other than calcium supplements), digoxin, lithium, methotrexate, biotin \>30 µg/day, or systemic corticosteroids (other than as replacement therapy)
• Use of thiazide diuretic within 4 weeks prior to the 24-hour urine collection scheduled to occur within 1 week prior to Visit 1
• Use of PTH-like drugs (whether commercially available or through participation in an investigational trial), including PTH (1-84), PTH (1-34), or other N-terminal fragments or analogs of PTH or PTH-related protein, within 4 weeks prior to Screening
• 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
• Pregnant or lactating women
• Male who has a female partner who intends to become pregnant or is of childbearing potential and is unwilling to use adequate contraceptive methods during the trial
• Diagnosed drug or alcohol dependence within 3 years prior to Screening
• Disease processes that adversely affect gastrointestinal absorption, including but not limited to short bowel syndrome, significant small bowel resection, gastric bypass, tropical sprue, active celiac disease, active ulcerative colitis, active Crohn's disease, gastroparesis and AIRE gene mutations with malabsorption
• Cerebrovascular accident within 5 years prior to Screening

Sponsors & Collaborators

• Visen Pharmaceuticals (Shanghai) Co., Ltd.: lead

Study Sites (1)

Peking Union Medical College Hospital

Beijing, Beijing Municipality, 100730, China

Location

MeSH Terms

Conditions

Hypoparathyroidism; Endocrine System Diseases; Parathyroid Diseases

Study Officials

• Weibo Xia, MD

  Department of endocrinology, Peking Union Medical College Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 3
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Subjects will be randomized 3:1 to receive either TransCon PTH or placebo: * TransCon PTH 18 μg/day\* , co-administered with SoC * Placebo for TransCon PTH (excipient solution) 18 μg/day, co-administered with SoC

Study Record Dates

• First Submitted: May 18, 2022
• First Posted: May 24, 2022
• Study Start: July 28, 2021
• Primary Completion: January 4, 2023
• Study Completion: January 8, 2026
• Last Updated: January 16, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)