Study of TST002 Injection in Postmenopausal Women With Osteoporosis or Low Bone Mass

NCT07806331 | Not Yet Recruiting Phase 2

• 1 other identifier: TST002-1001
• Study Type: interventional
• Target: 110
• Locations: 0 countries
• Sites: N/A

Brief Summary

This is a randomized, double-blind, placebo- and active-controlled Phase II study evaluating the efficacy and safety of TST002 injection (a humanized monoclonal antibody) in postmenopausal women with osteoporosis or low bone mass, aged 45-80 years. Approximately 110 participants will be randomized 1:1:1:1:1 (stratified by baseline BMD T-score) to one of five arms: TST002 400 mg every 8 weeks (Q8W), TST002 800 mg Q8W, TST002 1200 mg every 12 weeks (Q12W), placebo, or open-label denosumab 60 mg subcutaneously every 24 weeks. The study includes a screening period (Day -28 to Day -1), a main study period (Week 0-24), and an extension period (Week 25-52), with all participants followed through Week 52 (Day 365). The primary objective is to evaluate the effect of repeated IV TST002 infusions on lumbar spine bone mineral density (BMD). Secondary objectives include characterization of pharmacokinetics, pharmacodynamics, immunogenicity, safety, and tolerability.

Conditions

Postmenopausal Osteoporosis; Low Bone Mass

Keywords

TST002; bone mineral density; postmenopausal osteoporosis; low bone mass; sclerostin; monoclonal antibody; DXA

Outcome Measures

Primary Outcomes (1)

• Percent change from baseline in lumbar spine Bone Mineral Density (BMD)

  Lumbar spine (L1-L4) bone mineral density, central imaging read (DXA)

  Baseline to Week 24

Secondary Outcomes (19)

• Percent change from baseline in lumbar spine Bone Mineral Density (BMD)

  Weeks 12 and 52

• Percent change from baseline in total hip Bone Mineral Density (BMD)

  Weeks 12, 24, and 52

• Percent change from baseline in femoral neck Bone Mineral Density (BMD)

  Weeks 12, 24 and 52

• TST002 plasma concentration

  Up to 52 weeks

• Percent change from baseline in bone turnover markers

  Up to 52 weeks

Study Arms (5)

TST002 400 mg Q12W

EXPERIMENTAL

IV infusion 400 mg on D1(W0), W8, W16, W24, W32, W40, W48; placebo infusion at W12, W24, W36, W48

Drug: Placebo

TST002 800 mg Q12W

EXPERIMENTAL

IV infusion 800 mg on D1(W0), W8, W16, W24, W32, W40, W48; placebo infusion at W12, W24, W36, W48

Drug: Placebo

TST002 1200 mg Q12W

EXPERIMENTAL

TST002 1200 mg D1(W0), W12, W24, W36, W48; placebo infusion at W12, W24, W36, W48

Drug: Placebo

Placebo

PLACEBO COMPARATOR

IV placebo on D1(W0), W12, W24, W36, W48; crosses over to open-label TST002 in extension phase (dose per primary analysis)

Drug: Denosumab

Denosumab

ACTIVE COMPARATOR

Denosumab 60 mg subcutaneous injection at D1(W0) and W24 (open-label)

Drug: Placebo

Interventions

Placebo DRUG

Vehicle Placebo

Denosumab; TST002 1200 mg Q12W; TST002 400 mg Q12W; TST002 800 mg Q12W

Denosumab DRUG

Active comparator

Placebo

Eligibility Criteria

• Age: 45 Years - 80 Years
• Gender Eligibility Details: Postmenopausal females
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Voluntary signed informed consent; able to walk freely; willing/able to complete all study procedures.
• BMI 18.0-30.0 kg/m² (inclusive); body weight ≥45 kg.
• Postmenopausal women aged 45-80 years (inclusive) at screening, postmenopausal ≥2 years (≥12 consecutive months without spontaneous vaginal bleeding/spotting).
• BMD T-score \<-2.00 at lumbar spine (L1-L4 total), total hip, or femoral neck at screening; OR history of fragility fracture with T-score \<-1.00 at one of these sites (central imaging read).
• At least 2 contiguous evaluable vertebrae (L1-L4) and at least one evaluable hip for DXA assessment.
• No disease, per investigator history/exam/workup, likely to significantly affect the study or increase health risk (documented exceptions permitted with justification).

You may not qualify if:

• BMD T-score ≤-3.50 at lumbar spine, total hip, or femoral neck at screening.
• Prior hip fracture.
• ≥2 vertebral fractures on screening lateral spine X-ray (investigator-assessed).
• Known skeletal, endocrine, or rheumatic disease that could confound results (e.g., Paget's disease, osteomalacia, osteopetrosis, osteogenesis imperfecta, sclerosteosis, rheumatoid arthritis, ankylosing spondylitis, Cushing's disease, hyperprolactinemia, uncontrolled thyroid disease, hyper-/hypoparathyroidism, or CN VIII compression hearing loss).
• Prior osteoporosis therapy (incl. trial participation) within protocol-specified washout windows (IV bisphosphonates, oral bisphosphonates, denosumab/cathepsin K inhibitors, tibolone/cinacalcet/calcitonin, teriparatide/PTH analogs, systemic estrogen/SERMs, strontium ranelate/fluoride, hormonal castration therapy, systemic glucocorticoids ≥5 mg/day prednisone-equivalent for \>14 days) - see protocol for exact windows per agent.
• History of TMJ disorder, TMJ osteonecrosis, or atypical fracture.
• Hypercalcemia or hypocalcemia (albumin-corrected) at screening.
• Serum 25(OH)D \<20 ng/mL at screening.
• History of MI, or serious cardiac disease (CAD, NYHA class II-IV heart failure) within 6 months before screening.
• History of stroke (cerebral infarction, ischemic or hemorrhagic).
• ALT/AST \>3× ULN; ALP \>2.5× ULN; total bilirubin or creatinine \>1.5× ULN at screening.
• Multiple myeloma, primary/metastatic bone malignancy, or history of skeletal radiotherapy.
• Malignancy within 5 years before screening (except cured skin squamous/basal cell carcinoma or documented cured in situ cervical cancer, no recurrence ≥3 months before dosing).
• Known hypersensitivity to study drug.
• History of solid organ or bone marrow transplant.

Sponsors & Collaborators

• Transcenta Therapeutics (Hangzhou) Co., Ltd.: lead

MeSH Terms

Conditions

Osteoporosis, Postmenopausal; Sclerosteosis

Interventions

Denosumab

Condition Hierarchy (Ancestors)

Osteoporosis; Bone Diseases, Metabolic; Bone Diseases; Musculoskeletal Diseases; Metabolic Diseases; Nutritional and Metabolic Diseases

Intervention Hierarchy (Ancestors)

Antibodies, Monoclonal, Humanized; Antibodies, Monoclonal; Antibodies; Immunoglobulins; Immunoproteins; Blood Proteins; Proteins; Amino Acids, Peptides, and Proteins; Serum Globulins; Globulins

Central Study Contacts

Vicky Zhong

CONTACT

+86-0571-28279502; vicky.zhong@transcenta.com

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Double-blind (Participant, Investigator) TST002 doses or placebo; denosumab arm open-label

Study Record Dates

• First Submitted: August 20, 2026
• First Posted: September 8, 2026
• Study Start (Estimated): October 31, 2026
• Primary Completion (Estimated): April 30, 2027
• Study Completion (Estimated): October 31, 2028
• Last Updated: September 11, 2026

Record last verified: 2026-09

Data Sharing

• IPD Sharing: Will not share