Data Presented at ASCO Demonstrate Trilaciclib Helps Protect Against Severe Neutropenia, Severe Anemia, and Severe Thrombocytopenia When Given to Extensive-Stage Small Cell Lung Cancer (ES-SCLC) Patients Prior to Chemotherapy

  – Patients Receiving Trilaciclib Experienced a Lower Incidence of Single-Lineage and Multilineage Chemotherapy-Induced Myelosuppressive Events Compared with Patients Receiving Placebo –

– Total Number of Patients Experiencing a Myelosuppressive Event was Lower with Trilaciclib Compared to Placebo –

RESEARCH TRIANGLE PARK, N.C., June 02, 2022 (GLOBE NEWSWIRE) — G1 Therapeutics, Inc. (Nasdaq: GTHX), a commercial-stage oncology company, today announced results of a post-hoc study analysis showing that ES-SCLC patients who received trilaciclib prior to chemotherapy had a lower incidence of single- and multilineage myelosuppressive events—fewer cases of severe neutropenia, severe anemia, and severe thrombocytopenia—compared to patients receiving placebo. Moreover, the proportion of patients who experienced at least one multilineage myelosuppressive event was lower in the trilaciclib arm compared to the placebo arm. The data, derived from a post-hoc analysis of Phase 2 trials, were presented in a poster at the 2022 American Society of Clinical Oncology (ASCO) annual meeting.

“Myelosuppression is a major toxicity of chemotherapy treatment for patients with extensive-stage small cell lung cancer that often results in chemotherapy dose delays and dose reductions, both of which can compromise clinical outcomes,” said Jerome Goldschmidt, M.D., medical oncologist with Blue Ridge Cancer Care in Blacksburg, VA, and lead author of the poster. “Both the patients and the healthcare system at large bear the complications of myelosuppressive events such as neutropenia, anemia, and thrombocytopenia, so it is imperative that we achieve clinically meaningful reductions in myelosuppression in multiple cell lineages and its consequences utilizing novel therapies such as trilaciclib.”

In the analysis, the researchers calculated the number of patients who experienced single lineage and multilineage myelosuppressive events as well as the total number of events each person experienced in both first-line and second/third-line chemotherapy settings. Only severe grade events (grade ≥ 3 per the National Cancer Institute) were included in the analysis, and 75 percent of patients were in the first-line setting.

Results of the analysis showed that throughout cycles one through four of first-line therapy, fewer patients treated with trilaciclib experienced single-lineage (neutrophil, red blood cell or platelet lineages) and multilineage myelosuppressive events—and fewer events occurred per person—than patients who received placebo.

Specifically, analyses of the pooled data showed that patients receiving trilaciclib in the first-line setting experienced fewer single-lineage myelosuppressive events, including:

• a 75% reduction (56.7% to 14.4%) in severe neutropenia compared to patients receiving placebo
• a 50% reduction (17.8% to 8.9%) in severe anemia compared to patients receiving placebo
• a 100% reduction (12.2% to 0.0%) in severe thrombocytopenia compared to patients receiving placebo

Additionally, analyses of the pooled data showed that patients receiving trilaciclib in the first-line setting experienced fewer concurrent, multilineage myelosuppressive events, including:

• a 100% reduction (2.2% to 0.0%) in concurrent severe anemia, severe neutropenia, severe thrombocytopenia compared to patients receiving placebo.
• a 100% reduction (13.3% to 0.0%) in concurrent severe neutropenia and severe thrombocytopenia compared to patients receiving placebo
• a 50% reduction (4.4% to 2.2%) in concurrent severe neutropenia and severe anemia compared to patients receiving placebo
• a 33% reduction (3.3% to 2.2%) in concurrent severe anemia and severe thrombocytopenia compared to patients receiving placebo

Concurrent events were defined as having two or three lineage-specific myelosuppressive events overlap for at least one day.

The ASCO poster, titled, “Impact of Trilaciclib on Multilineage Chemotherapy-Induced Myelosuppression Events in Patients with Extensive-Stage Small-Cell Lung Cancer: Post-Hoc Analyses of Data from Randomized Clinical Trials,” can be found here.

About Small Cell Lung Cancer

In the United States, approximately 30,000 small cell lung cancer patients are treated annually. SCLC, one of the two main types of lung cancer, accounts for about 10% to 15% of all lung cancers. SCLC is an aggressive disease and tends to grow and spread faster than NSCLC. It is usually asymptomatic; once symptoms do appear, it often indicates that the cancer has spread to other parts of the body. About 70% of people with SCLC will have cancer that has metastasized at the time they are diagnosed. The severity of symptoms usually increases with increased cancer growth and spread. From the time of diagnosis, the general 5-year survival rate for people with SCLC is 6%. The five-year survival rates for limited-stage (the cancer is confined to one side of the chest) SCLC is 12% to 15%, and for extensive stage (cancer has spread to the other lung and beyond), survival rates are less than 2%. Chemotherapy is the most common treatment for ES-SCLC. A majority (>90%) of ES-SCLC patients receive first-line chemotherapy at the time of treatment initiation.

About G1 Therapeutics
G1 Therapeutics, Inc. is a commercial-stage biopharmaceutical company focused on the development and commercialization of next generation therapies that improve the lives of those affected by cancer, including the Company’s first commercial product, COSELA® (trilaciclib). G1 has a deep clinical pipeline and is executing a tumor-agnostic development plan evaluating trilaciclib in a variety of solid tumors, including colorectal, breast, lung, and bladder cancers. G1 Therapeutics is based in Research Triangle Park, N.C. For additional information, please visit www.g1therapeutics.com and follow us on Twitter @G1Therapeutics.

G1 Therapeutics™ and the G1 Therapeutics logo and COSELA® and the COSELA logo are trademarks of G1 Therapeutics, Inc.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “may,” “will,” “expect,” “plan,” “anticipate,” “estimate,” “intend” and similar expressions (as well as other words or expressions referencing future events, conditions or circumstances) are intended to identify forward-looking statements. Forward-looking statements in this press release include, but are not limited to the potential value of, and need for, myeloprotective interventions such as trilaciclib in the management of multilineage myelosuppression, are based on the company’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements involves risks and uncertainties. Factors that may cause the company’s actual results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in the company’s filings with the U.S. Securities and Exchange Commission, including the “Risk Factors” sections contained therein and include, but are not limited to, the company’s ability to complete a successful commercial launch for COSELA (trilaciclib); the company’s ability to complete clinical trials for, obtain approvals for and commercialize any of its product candidates other than COSELA (trilaciclib); the company’s initial success in ongoing clinical trials may not be indicative of results obtained when these trials are completed or in later stage trials; the inherent uncertainties associated with developing new products or technologies and operating as a commercial-stage company; and market conditions. Except as required by law, the company assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available.

G1 Therapeutics Contacts:

Will Roberts
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919-907-1944
wroberts@g1therapeutics.com

Rebecca Levine
Director, Corporate Communications and Public Relations
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rlevine@g1therapeutics.com