CClinicalTrials.gg
Sign In
Status unknownNCT02983071Updated Feb 15, 2023

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

A Phase 1/2 interventional study of G1T38 and Fulvestrant in Carcinoma, Ductal, Breast, Breast Cancer and Breast Neoplasm, sponsored by G1 Therapeutics, Inc.. Status unknown at 8 sites in 4 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2023-02-15.

Sponsored by G1 Therapeutics, Inc. · Phase 1/2, Interventional, and Treatment

The sponsor has not verified this record recently (last verified Feb 2023), so the status shown — last known as Active, not recruiting — may be out of date.
Phase
Phase 1/2
Study type
Interventional
Enrollment
102
Allocation
Non-randomized
Ages
18 Years and older
Sex
All
01

Study summary

This is a study to investigate the potential clinical benefit of G1T38 as an oral therapy in combination with fulvestrant in patients with hormone receptor-positive, HER2-negative metastatic breast cancer.

The study is an open-label design, consists of 2 parts: dose-finding portion (Part 1), and expansion portion (Part 2). Both parts include 3 study phases: Screening Phase, Treatment Phase, and Survival Follow-up Phase. The Treatment Phase begins on the day of first dose with study treatment and completes at the Post-Treatment Visit. Approximately, 102 patients will be enrolled in the study.

02

Conditions studied

  • Carcinoma, Ductal, Breast
  • Breast Cancer
  • Breast Neoplasm

Keywords

  • Breast Cancer
  • CDK 4/6 Inhibitor
  • HER2-Negative
  • HR-Positive
  • HR+
  • HER2-
  • HER2 -ve
  • HER2 +ve
03

In context

Breast Neoplasms

12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.

This study's planned enrollment of 102 is above the median of 72 across 9,303 interventional studies indexed under Breast Neoplasms.

Browse Breast Neoplasms studies →

Lead sponsor

G1 Therapeutics, Inc. is the lead sponsor of 16 studies on the registry; none are open to participants now.

Of its 12 completed or terminated interventional studies of FDA-regulated products, 10 (83%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

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

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
05

Study design

Phase
Phase 1 / Phase 2
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
102 participants (estimated)

Study arms

  • Experimental
    Once-Daily G1T38 Dosing

    G1T38 (lerociclib) orally (once daily) in combination with fulvestrant.

    Drug: G1T38 · Drug: Fulvestrant

  • Experimental
    Twice-Daily G1T38 Dosing

    G1T38 (lerociclib) orally (twice daily) in combination with fulvestrant.

    Drug: G1T38 · Drug: Fulvestrant

Interventions

  • DrugG1T38

    Also known as: lerociclib

  • DrugFulvestrant

    Also known as: Faslodex

06

What researchers measure

Primary outcomes

  1. Dose Limiting Toxicity

    Time frame: Week 1 Day 1-Week 5 Day 1

  2. Recommended Phase 2 dose

    Time frame: 14 months

  3. Recommended Phase 2 dose interval

    Twice-Daily or Once-Daily dosing

    Time frame: 14 months

  4. Number of Treatment Related Adverse Event, including Abnormal Laboratory Events

    All AEs, including clinical laboratory, vitals signs, physical examinations and ECGs will be analyzed in all patients receiving study drug from the signing of the informed consent until 30 days after the last dose of study medication up to 36 months

    Time frame: 36 months

Secondary outcomes

  1. Tumor response based on RECIST, Version 1.1

    Time frame: 30 months

  2. Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Maximum Plasma Concentration (Cmax)

    Time frame: Week 1 Day 1-Week 9 Day 1

  3. Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Area under Curve - plasma concentration (AUC)

    Time frame: Week 1 Day 1-Week 9 Day 1

  4. Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Plasma: terminal half life (T1/2)

    Time frame: Week 1 Day 1-Week 9 Day 1

  5. Pharmacokinetics of G1T38, Fulvestrant, and Goserelin: Plasma - Volume of distribution

    Time frame: Week 1 Day 1-Week 9 Day 1

  6. Progression free survival (PFS)

    Time frame: 36 months

  7. Overall survival (OS)

    Time frame: 48 months

07

Study locations

8 sites
  • MHAT for Womens Health - Nadezhda OOD
    Sofia, 1330, Bulgaria
  • Special Hospital For Active Treatment In Oncology
    Sofia, 1756, Bulgaria
  • ARENSIA Exploratory Medicine LLC
    Tbilisi, 0112, Georgia
  • The Institute of Oncology
    Chisinau, 2025, Moldova, Republic of
  • Cambridge University
    Cambridge, CB2 0QQ, United Kingdom
  • University College London Hospital (UCLH)
    London, NW1 2BU, United Kingdom
  • Sarah Cannon Research Institute
    London, W1G 6AD, United Kingdom
  • The Christie NHS Foundation
    Manchester, M20 4BX, United Kingdom
08

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Feb 15, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
09

Registry details

Key details

Study ID
NCT02983071
Lead sponsor
G1 Therapeutics, Inc.
Responsible party
Sponsor
First posted
Dec 6, 2016
Start date
Jan 2017
Primary completion
Jun 2023 (estimated)
Completion
Oct 2023 (estimated)
Last update
Feb 15, 2023

Study contacts

Clinical Contact
study director · G1 Therapeutics, Inc.

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is status unknown, as verified in Feb 2023. You cannot join it, but the record below documents what was studied.

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Other studies in this condition

Breast Neoplasms→

Other studies from this sponsor

G1 Therapeutics, Inc.

Start the discussion