FDA Grants Priority Review to Trilaciclib in Chemotherapy-Treated Small Cell Lung Cancer

The FDA granted Priority Review to the New Drug Application for trilaciclib for the treatment of patients with small cell lung cancer who are receiving chemotherapy.

The FDA has granted Priority Review to the New Drug Application (NDA) for trilaciclib (G1T28) for the treatment of patients with small cell lung cancer (SCLC) who are receiving chemotherapy, G1 Therapeutics announced in a press release. The Prescription Drug User Fee Act has an action date of February 15, 2021.

“There are currently no available therapies to protect patients from chemotherapy-induced toxicities before they occur,” said Raj Malik, MD, chief medical officer and senior vice president, R&D, in a statement. “If approved, trilaciclib would be the first proactively administered myelopreservation therapy that is intended to make chemotherapy safer and reduce the need for rescue interventions, such as growth factor administrations and blood transfusions.”

Trilaciclib, the first-in-class investigational agent, is used to preserve bone marrow and immune system function during chemotherapy treatment in order to improve outcomes for patients with SCLC. Myelosuppression, which occurs as a result of damage to bone marrow stem cells, is 1 of the most common side effects of chemotherapy and can lead to serious conditions, including anemia, neutropenia, or thrombocytopenia. This can have broad-ranging clinical patient experience and economic impacts on ongoing treatment and outcomes.

If this treatment is approved, it would be a significant improvement in the safety and effectiveness of the treatment, diagnosis, or prevention of serious conditions when compared with standard treatments. The NDA is supported by data from 3 randomized clinical trials in which trilaciclib was administered to patients prior to receiving chemotherapy.

Trilaciclib significantly reduced chemotherapy-induced myelosuppression in clinical trials. Patients who receive this treatment also experience fewer dose delays, reductions, infections, hospitalizations, and need for rescue therapies compared with patients who receive chemotherapy alone.

Although this NDA is under regulatory review, the company is making trilaciclib available to patients with SCLC who are ineligible to enter clinical trials and have no other appropriate alternative treatment options under the FDA’s expanded access program. G1 Therapeutics is collaborating with Bionical Emas to facilitate this access.

“Complications from myelosuppression have been a long-standing challenge when treating patients with SCLC,” stated Malik. “Establishing an expanded access program provides qualified patients in serious need with access to trilaciclib while the NDA is under review.”

In a randomized phase 2 clinical trial (NCT02978716) in which women with metastatic triple-negative breast cancer were treated with trilaciclib, overall survival (OS) was improved when the agent was given in combination with chemotherapy compared with chemotherapy alone.

Overall, 102 patients were enrolled and randomized to receive chemotherapy alone or in combination with trilaciclib. The study was conducted in 2 phases, including the screening phase, treatment phase, and survival follow-up phase. The primary end point was the number of treatment-related adverse events, and secondary end points included tumor response, progression-free survival, and OS, among others. The final OS data from this trial are expected to be shared in the fourth quarter of 2020.

The agent is also under evaluation as neoadjuvant treatment of patients with breast cancer in the I-SPY 2 study (NCT01042379). A phase 3 clinical trial will also evaluate trilaciclib as treatment of patients with colorectal cancer later this year.

“While undergoing chemotherapy, many patients experience significant myelosuppression, become fatigued and susceptible to infection, and often require transfusions and growth factor administrations,” stated Jared Weiss, MD, Lineberger Comprehensive Cancer Center, University of North Carolina Chapel Hill, NC. “Preventing bone marrow damage proactively is an opportunity to improve the quality of life of patients receiving chemotherapy for small cell lung cancer and reduce costly rescue interventions.”

Trilaciclib was previously granted a Breakthrough Therapy Designation by the FDA in 2019, and the FDA also stated in the NDA acceptance letter that there are no plans to hold an advisory committee meeting to discuss the application.


G1 Therapeutics Announces Acceptance and Priority Review of NDA for Trilaciclib for Patients With Small Cell Lung Cancer. News Release. G1 Therapeutics. August 17, 2020. Accessed August 17, 2020. https://bit.ly/2YaUek1