Trilaciclib (G1T28) in Patients With Previously Treated Extensive Stage SCLC Receiving Topotecan Chemotherapy
This was a study to investigate the potential clinical benefit of trilaciclib (G1T28), a Cyclin Dependent Kinase (CDK) 4/6 inhibitor, in preserving the bone marrow and the immune system, in order to decrease chemotherapy-induced myelosuppression and improve anti-tumor efficacy when administered prior to topotecan in patients previously treated for extensive-stage SCLC. The study consisted of 2 parts: a limited open-label, dose-finding portion (Part 1), and a randomized double-blind portion (Part 2). Both parts included 3 study phases: Screening Phase, Treatment Phase, and Survival Follow-up Phase. The Treatment Phase began on the day of first dose with study treatment and completes at the Post-Treatment Visit.
Ask AI to explain this studyKey things to know
This describes the study’s primary purpose.
Plus 1 other study approaches.
These are broad labels—not an eligibility decision.
Checked against the public recordLast updated Sep 25, 2025 · Source: ClinicalTrials.gov
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Interventional
Locations may change over time.
Study sponsor
What this study is about
- Purpose
- Treatment
- Study type
- Interventional
- Phase
- Phase 1 / Phase 2
- Sponsor
- G1 Therapeutics, Inc.
- Interventions being studied
- Drug: Trilaciclib; Drug: Placebo; Drug: Topotecan
How this study is categorized
These labels come from structured fields and exact terms in the public record.
Who may be able to participate
The sponsor separates these requirements into two groups. You do not need to interpret them alone—use them to guide a conversation with the study team.
- Key
- Male or female subjects aged ≥18 years
- Confirmed diagnosis of SCLC by histology or cytology, preferably including the presence of neuroendocrine features by immunohistochemistry
- Progression during or after prior first- or second-line chemotherapy and eligible to receive topotecan therapy
- At least 1 target lesion that is measurable by RECIST, Version 1.1
- Eastern Cooperative Oncology Group (ECOG) performance status of 0 - 2
- Adequate organ function Key
- Presence of brain metastases requiring immediate treatment with radiation therapy or steroids.
- Uncontrolled ischemic heart disease or uncontrolled symptomatic congestive heart failure
- Known history of stroke or cerebrovascular accident within 6 months prior to enrollment
- Other uncontrolled serious chronic disease or conditions that in the investigator's opinion could affect compliance or follow-up in the protocol
- Concurrent radiotherapy to any site or radiotherapy within 2 weeks prior to enrollment or previous radiotherapy to the target lesion sites
- Receipt of any systemic chemotherapy regimen within 4 weeks prior to enrollment or a noncytotoxic investigational medication within 2 weeks prior to enrollment
- History of topotecan treatment for SCLC
Important: This is the sponsor’s public criteria, not a determination of eligibility. The study team must review your individual situation.
U.S. locations
- Genesis Cancer CenterHot Springs, Arkansas
- Highlands Oncology GroupRogers, Arkansas
- Compassionate Cancer Care Medical Group, Inc.Corona, California
- Sutter Medical GroupSacramento, California
- The Oncology Institute of Hope and InnovationWhittier, California
- Memorial Hospital - University of Colorado HealthColorado Springs, Colorado
- Rocky Mountain Cancer CentersDenver, Colorado
- University of Colorado Health, Oncology Clinical Research Northern RegionFort Collins, Colorado
- Florida Cancer Specialists - SouthFort Myers, Florida
- Florida Cancer Specialists - NorthTavares, Florida
- University Cancer and Blood Center, LLCAthens, Georgia
- Emory UniversityAtlanta, Georgia
Source and freshness
Processed from ClinicalTrials.gov. Last public update: Sep 25, 2025. Always confirm current availability with the study team.