G1T38, a CDK 4/6 Inhibitor, in Combination With Fulvestrant in Hormone Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer

• Register: ClinicalTrials.gov
• Last refreshed on: 27 February 2023
• Main ID: NCT02983071
• Date of registration: 29/11/2016
• Prospective Registration: Yes
• Primary sponsor: G1 Therapeutics, Inc.
• Public title: G1T38, a CDK 4/6 Inhibitor, in Combination With Fulvestrant in Hormone Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer
• Scientific title: Phase 1/2 Safety, Pharmacokinetic, and Antitumor Activity Study of G1T38 in Combination With Fulvestrant in Patients With Hormone Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer After Endocrine Failure
• Date of first enrolment: January 2017
• Target sample size: 102
• Recruitment status: Active, not recruiting
• URL: https://clinicaltrials.gov/show/NCT02983071
• Study type: Interventional
• Study design: Allocation: Non-Randomized. Intervention model: Parallel Assignment. Primary purpose: Treatment. Masking: None (Open Label).
• Phase: Phase 1/Phase 2

Countries of recruitment

Bulgaria, Czech Republic, Czechia, Georgia, Moldova, Republic of, Romania, United Kingdom

Contacts

• Name: Clinical Contact
• Affiliation: G1 Therapeutics, Inc.

Key inclusion & exclusion criteria

Inclusion Criteria:

- Confirmed diagnosis of HR-positive, HER2-negative breast cancer, not amenable to
curative therapy

- Pre- or perimenopausal women can be enrolled if amenable to be treated with goserelin

- Patients must satisfy 1 of the following criteria for prior therapy:

- Progressed during treatment or within 12 months of completion of adjuvant therapy
with an aromatase inhibitor or tamoxifen

- Progressed during treatment or within 2 months after the end of prior aromatase
inhibitor therapy for advanced/metastatic breast cancer, or prior endocrine
therapy for advanced/metastatic breast cancer

- Received = 2 chemotherapy regimens (Part 1) or = 1 chemotherapy regimen (Part 2)
for advanced/metastatic disease

- For Part 1, evaluable or measurable disease (bone only disease eligible for Part 1
only)

- For Part 2, measurable disease as defined by RECIST, Version 1.1

- ECOG performance status 0 to 1

- Adequate organ function

Exclusion Criteria:

- For Part 1, prior treatment with fulvestrant

- For Part 2, prior treatment with any CDK inhibitor or fulvestrant

- Active uncontrolled/symptomatic CNS metastases, carcinomatous meningitis, or
leptomeningeal disease

- Chemotherapy within 21 days of first G1T38 dose

- Investigational drug within 28 days of first G1T38 dose

- Concurrent radiotherapy, radiotherapy within 14 days of first G1T38 dose, previous
radiotherapy to the target lesion sites, or prior radiotherapy to > 25% of bone marrow

- Prior hematopoietic stem cell or bone marrow transplantation



Age minimum: 18 Years
Age maximum: N/A
Gender: All

Health Condition(s) or Problem(s) studied

Breast Neoplasm

Carcinoma, Ductal, Breast

Breast Cancer

Intervention(s)

Drug: Fulvestrant

Drug: G1T38

Primary Outcome(s)

Recommended Phase 2 dose interval [Time Frame: 14 months]

Dose Limiting Toxicity [Time Frame: Week 1 Day 1-Week 5 Day 1]

Number of Treatment Related Adverse Event, including Abnormal Laboratory Events [Time Frame: 36 months]

Recommended Phase 2 dose [Time Frame: 14 months]

Secondary Outcome(s)

Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Area under Curve - plasma concentration (AUC) [Time Frame: Week 1 Day 1-Week 9 Day 1]

Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Plasma - Volume of distribution [Time Frame: Week 1 Day 1-Week 9 Day 1]

Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Plasma: terminal half life (T1/2) [Time Frame: Week 1 Day 1-Week 9 Day 1]

Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Maximum Plasma Concentration (Cmax) [Time Frame: Week 1 Day 1-Week 9 Day 1]

Tumor response based on RECIST, Version 1.1 [Time Frame: 30 months]

Overall survival (OS) [Time Frame: 48 months]

Progression free survival (PFS) [Time Frame: 36 months]

Secondary ID(s)

2016-001485-29

G1T38-02

Source(s) of Monetary Support

Please refer to primary and secondary sponsors