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A Phase Ib Study of GB491 Plus Letrozole in Patients With Advanced Breast Cancer

Phase 1
Conditions
Advanced Breast Cancer
Interventions
Drug: GB491+Letrozole
Registration Number
NCT05337657
Lead Sponsor
Genor Biopharma Co., Ltd.
Brief Summary

GB491-005 is a multicenter, open-label, phase Ib Clinical Trial study to evaluate the safety, pharmacokinetic (PK), pharmacodynamic (PD) activity, and preliminary anti-tumor activity of GB491 in combination with Letrozole in Previously Untreated Patients with HR-positive, HER2-negative Advanced Breast Cancer

Detailed Description

Not available

Recruitment & Eligibility

Status
UNKNOWN
Sex
Female
Target Recruitment
10
Inclusion Criteria
  1. Females of 18 years of age or older at study screening
  2. Histologically or cytologically confirmed locally advanced or advanced metastatic breast cancer that is not amenable to curative surgical resection or radiation therapy
  3. The subject has been diagnosed with ER-positive breast cancer in the local laboratory
  4. The subject has HER2-negative breast cancer in the local laboratory
  5. Menopausal status is not limited (including Premenopausal/perimenopausal/postmenopausal state)
  6. No previous systemic anti-tumor treatment for locally advanced or metastatic breast cancer;
  7. According to RECIST V1.1, the patient has at least one measurable lesion that has not been irradiated by radiotherapy and can be evaluated by CT/MRI; If only bone metastases are present, there must be at least one osteolytic bone lesion that can be evaluated by CT/MRI
  8. ECOG performance status of 0 or 1
  9. Adequate organ and marrow function.
  10. The subject of childbearing potential must use one highly effective birth control method from the total duration of the study and 6 months after the last dose of study intervention.
  11. Provide informed consent
Exclusion Criteria
  1. Previous treatment with CDK4/6 inhibitors
  2. Subjects with known hypersensitivity to any component of GB491 or Letrozole
  3. Patients with disease progression or recurrence during or within 1 year after completion of previous endocrine neoadjuvant or adjuvant therapy
  4. Known active, uncontrolled, or symptomatic central nervous system metastasis, carcinomatous meningitis, or clinically manifested leptomeningeal disease, cerebral edema, spinal compression or/and tumor progressive growth
  5. Visceral crisis
  6. Patients with skin lesion only and radiographically non-measurable at baseline
  7. Persistent toxicities (CTCAE Grade ≥ 2) caused by previous anticancer therapy, excluding alopecia
  8. Major surgical procedure within 4 weeks of the first dose of study treatment or an anticipated need for major surgery, chemotherapy, radiotherapy, any other investigational drug or other anti-cancer therapy during the study
  9. Patients who have been on bisphosphonates and denosumab therapy at a stable dose for less than 14 days prior to randomization
  10. Patients who have received limited field radiotherapy in 2 weeks or extended field radiotherapy in 4 weeks before randomization or radiation with more than 30% of the bone marrow
  11. Subjects use drugs or fruits containing strong inducers or inhibitors of CYP3A4/5, or drugs with narrow therapeutic window that are mainly metabolized by CYP3A4/5 in 14 days before randomization
  12. Patients with long-term systematic use of corticosteroids
  13. Any severe and/or uncontrollable medical conditions
  14. Patients with severely impaired lung function
  15. Known history of HIV infection or history of HIV seropositivity
  16. Resting QTcF > 480 msec or there is a medical history of QTcF prolongation
  17. Subjects have significant hepatic disease
  18. Coagulation abnormalities
  19. Refractory nausea and vomiting, inability to swallow the formulated product, or other disease or clinical status would preclude adequate absorption, distribution, metabolism, or excretion of GB491
  20. Previous allogeneic bone marrow transplant
  21. Inflammatory breast cancer;
  22. Subjects with a history of other primary malignancies, except for non-melanoma skin cancer and cervical cancer in situ disease-free status ≥ 3 years
  23. Lactating women
  24. Unlikely to comply with study procedures, restrictions, and requirements
  25. Judgment by the investigator that the patient should not participate into the study

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
GB491+LetrozoleGB491+Letrozole-
Primary Outcome Measures
NameTimeMethod
DLTDuring Cycle 1 (up to 28 days)

Number of Participants with Dose-Limiting Toxicities for GB491 in Combination with Letrozole

AEFrom Baseline until 30 days after the last treatment

Number of Participants with Adverse Events by Severity, According to National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI-CTCAE v5.0)

Secondary Outcome Measures
NameTimeMethod
PFSApproximately 2 years

To assess the progression free survival assessed by investigator

ORRApproximately 2 years

To assess the objective response rate for GB491 in Combination with Letrozole

DORApproximately 2 years

To assess the duration of response for GB491 in Combination with Letrozole

DCRApproximately 2 years

To assess the disease control rate for GB491 in Combination with Letrozole

CBRApproximately 2 years

To assess the clinical benefit rate for GB491 in Combination with Letrozole by investigator

Plasma Concentration of GB491At predefined intervals from Cycle 1, Day 1 & Day 15; Cycle 2, Day 1 (each cycle is 28 days)

Plasma Concentration of GB491 Over Time

Plasma Concentration of LetrozoleAt predefined intervals from Cycle 1, Day 1 & Day 15; Cycle 2, Day 1 (each cycle is 28 days)

Plasma Concentration of Letrozole Over Time

Trial Locations

Locations (1)

Fudan University Shanghai Cancer Center

🇨🇳

Shanghai, Shanghai, China

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