Trilaciclib Increases Pool of Memory T Cells in the Tumor Microenvironment Responsible for Long Term Immune Surveillance and Efficacy
RESEARCH TRIANGLE PARK, N.C., June 04, 2023 (GLOBE NEWSWIRE) -- G1 Therapeutics, Inc. (Nasdaq: GTHX), a commercial-stage oncology company, today presented results from 24 patients enrolled in its Phase 2, single arm mechanism of action study of trilaciclib administered as a single agent to patients with early-stage triple-negative breast cancer (TNBC) prior to receiving trilaciclib and neoadjuvant therapy. These results highlight the potential for trilaciclib to enhance long term immune surveillance by increasing T cell function and generation of certain memory T cells and demonstrate gene expression profiles that may be associated with improved clinical outcome. These data support earlier findings from this Phase 2 trial demonstrating an increase in the ratio of CD8+ T cells to regulatory T cells (Tregs); a high ratio of CD8+ T cell to Tregs is predictive of overall survival (OS) and is associated with pathologic complete response (pCR). As expected, high rates of pCR were observed in patients with PD-L1(+) tumors and in patients with inflamed tumor immune microenvironments.
- As expected, high rates of pCR were observed in patients with PD-L1(+) tumors and in patients with inflamed tumor immune microenvironments.
- Data published by G1 and others show that trilaciclib can promote trafficking of immune cells out of the stroma and into the tumor microenvironment via chemokine release, thus leading to an inflamed tumor immune microenvironment status.
- Trilaciclib was shown to enhance the number and function of CD8+ T cells in the tumor microenvironment.
- These results help confirm the role of trilaciclib in increasing the pool of functional memory T cells that could contribute to long-term immune surveillance and efficacy, as measured by longer term endpoints like OS.