G1 Therapeutics Granted Priority Review of Potential Lung Cancer Therapy

G1 Therapeutics, a clinical-stage oncology company based in Research Triangle Park, has reached an important regulatory milestone for its potential therapy for small cell lung cancer.

The U.S. Food and Drug Administration accepted G1’s New Drug Application for trilaciclib and granted Priority Review of the therapy with an action date of Feb. 15, 2021, the company announced in a news release.

Trilaciclib is a first-in-class investigational therapy designed to preserve bone marrow and immune system function during chemotherapy and improve patient outcomes.

“There are currently no available therapies to protect patients from chemotherapy-induced toxicities before they occur,” said Raj Malik, M.D., G1’s chief medical officer and senior vice president of R&D. “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.”

The FDA grants Priority Review to applications for potential therapies that, if approved, would be significant improvements compared to currently available therapies.

‘Compelling’ clinical data

The trilaciclib NDA was supported by “compelling” myelopreservation data from three randomized, double-blind, placebo-controlled clinical trials in which trilaciclib was administered prior to chemotherapy treatment in patients with small cell lung cancer, according to G1.

“While undergoing chemotherapy, many patients experience significant myelosuppression, become fatigued and susceptible to infection, and often require transfusions and growth factor administrations,” said Jared Weiss, M.D., of the Lineberger Comprehensive Cancer Center at the University of North Carolina at Chapel Hill. “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.”

Myelosuppression is the result of damage to bone marrow stem cells and is a common side effect of chemotherapy. Myelosuppression can lead to serious conditions such as anemia, neutropenia or thrombocytopenia, which have broad-ranging clinical, patient experience and economic impacts on cancer treatment and outcomes.

In clinical trials, trilaciclib significantly reduced chemotherapy-induced myelosuppression, and patients receiving trilaciclib experienced fewer dose delays/reductions, infections, hospitalizations, and need for rescue therapies compared to patients receiving chemotherapy alone, the company reported.

Expanded access granted

Through the FDA’s expanded access program, G1 is making trilaciclib available to small cell lung cancer patients in the U.S. who are unable to enter clinical trials and for whom there are no appropriate alternative treatments while the trilaciclib NDA is under regulatory review.

Trilaciclib received FDA Breakthrough Therapy Designation in 2019. The designation expedites the development and review of drugs that treat a serious condition and show preliminary clinical evidence of improvement over currently available therapies.

In June 2020, G1 announced a co-promotion agreement with Boehringer Ingelheim for trilaciclib in small cell lung cancer in the U.S. and Puerto Rico. If the therapy is approved, G1 will lead marketing, market access and medical engagement for trilaciclib while Boehringer Ingelheim will lead sales force engagement.

G1 is evaluating trilaciclib for the treatment of additional cancers including breast cancer and colorectal cancer.

In a randomized trial of women with metastatic triple-negative breast cancer, preliminary data showed that trilaciclib improved overall survival when administered in combination with chemotherapy compared with chemotherapy alone. The company plans to present final overall survival data from this trial in the fourth quarter of 2020.

Trilaciclib is also being evaluated in neoadjuvant breast cancer as part of the I-SPY 2 TRIAL.

G1 said it expected to initiate a Phase 3 trial in patients treated with chemotherapy for colorectal cancer in the fourth quarter of 2020.

Other therapies advancing

In addition to trilaciclib, G1 is developing rintodestrant, a potential best-in-class oral selective estrogen receptor degrader for the treatment of estrogen receptor-positive breast cancer.

This summer the company out-licensed global development and commercialization rights to another potential cancer therapy, lerociclib, its differentiated oral CDK4/6 inhibitor. Lerociclib is being developed for use in combination with other targeted therapies in certain types of breast and lung cancer.

EQRx, based in Cambridge, Mass., gained exclusive rights to lerociclib in the United States, Europe, Japan and all other global markets, excluding the Asia-Pacific region (except Japan). Genor Biopharma, a biopharmaceutical company based in Shanghai, gained rights to lerociclib in the Asia-Pacific region (excluding Japan).

G1 is a 2008 spin-out of the University of North Carolina at Chapel Hill. The company raised $108 million in an initial public offering of stock in 2017 after receiving more than $95 million in three rounds of venture capital funding. The North Carolina Biotechnology Center provided two early stage loans totaling $500,000.

G1’s stock is traded on the Nasdaq Global Select Market under the ticker symbol GTHX.