G1 Therapeutics

G1 Therapeutics was an American biopharmaceutical company established in 2008 to discover, develop, and commercialize small-molecule medicines for cancer care. The company was founded by Norman Sharpless, a cancer researcher who later became director of the U.S. National Cancer Institute, and Kwok-Kin Wong. Its early research was connected with discoveries made in Sharpless's laboratory at the University of North Carolina at Chapel Hill, which G1 licensed for further development. Early financial backers included Hatteras Venture Partners, Fred Eshelman, MedImmune Ventures, and Cormorant Asset Management. The company's central scientific focus was the use of cyclin-dependent kinase, or CDK, inhibition to improve cancer treatment. Its lead program, trilaciclib, was designed as a transient CDK4/6 inhibitor administered before chemotherapy. Rather than functioning primarily as a direct anticancer agent, trilaciclib was developed to temporarily protect bone-marrow and immune-system precursor cells from chemotherapy-related damage. This approach, known as myelopreservation, was intended to reduce chemotherapy-induced myelosuppression, including severe neutropenia, anemia, and thrombocytopenia, while potentially supporting treatment delivery and immune function. G1 became a publicly traded company on the Nasdaq in May 2017 under the symbol GTHX. Trilaciclib advanced through randomized clinical studies in patients with small-cell lung cancer and other solid tumors. In June 2020, G1 submitted a New Drug Application to the U.S. Food and Drug Administration. The application received priority review, and the company created an expanded-access program while regulatory review was under way. On February 12, 2021, the FDA approved trilaciclib under the brand name Cosela for reducing the frequency of chemotherapy-induced myelosuppression in adults receiving certain chemotherapy regimens for extensive-stage small-cell lung cancer. The product became the principal commercial offering associated with G1 Therapeutics and was subsequently included in relevant National Comprehensive Cancer Network guidance as a prophylactic option in the indicated treatment setting. G1 also pursued development of trilaciclib in metastatic colorectal cancer, triple-negative breast cancer, non-small-cell lung cancer, bladder cancer, and breast cancer research conducted through the I-SPY program. Beyond trilaciclib, its pipeline included rintodestrant, an oral selective estrogen receptor degrader for estrogen-receptor-positive, HER2-negative advanced breast cancer, and lerociclib, an oral CDK4/6 inhibitor designed for continuous dosing and a potentially differentiated safety profile. The company entered licensing and collaboration arrangements covering these programs, including agreements with Boehringer Ingelheim, Simcere Pharmaceuticals, Pfizer, EQRx, Genor Biopharma, and ARC Therapeutics. Leadership changed during the company's transition from development-stage biotechnology business to commercial oncology company. In September 2020, G1 announced that chief executive Mark Velleca would step down at the beginning of 2021 and that Jack Bailey, formerly president of U.S. pharmaceuticals and vaccines at GlaxoSmithKline, would succeed him. In September 2024, Pharmacosmos announced completion of its purchase of G1 Therapeutics. As a result, G1's status changed from an independent Nasdaq-listed company to an acquired biopharmaceutical business within the Pharmacosmos group. Its identity remains principally associated with Cosela and with the development of oncology-supportive therapies based on transient CDK inhibition.

G1 Therapeutics was founded in 2008 by Norman Sharpless and Kwok-Kin Wong. The founders sought to translate small-molecule discoveries from Sharpless's University of North Carolina laboratory into medicines for cancer patients. The company's early financing came from venture and life-science investors including Hatteras Venture Partners, Fred Eshelman, MedImmune Ventures, and Cormorant Asset Management. G1's research centered on CDK4/6 inhibition. The company's principal candidate, trilaciclib, was developed as a short-acting, pre-chemotherapy treatment intended to temporarily arrest the cell cycle in vulnerable hematopoietic and immune cells. This mechanism was designed to protect bone marrow from chemotherapy-related injury, a strategy G1 described as myelopreservation. The candidate was also investigated for possible effects on immune function and antitumor treatment delivery. The company went public on May 17, 2017, trading on Nasdaq under GTHX. During the following years, it conducted clinical studies of trilaciclib in small-cell lung cancer and several other solid-tumor settings. In June 2020, G1 submitted a New Drug Application to the FDA. The application received priority review, and G1 opened an expanded-access program in September 2020 to provide eligible small-cell lung cancer patients access during the regulatory review period. On February 12, 2021, the FDA approved trilaciclib under the brand name Cosela. The approved use was to reduce the frequency of chemotherapy-induced myelosuppression in adults receiving certain chemotherapy regimens for extensive-stage small-cell lung cancer. In March 2021, the product was incorporated into NCCN Clinical Practice Guidelines as a prophylactic option in the relevant setting. Cosela became the company's principal commercial product. G1 continued to test trilaciclib in metastatic colorectal cancer, triple-negative breast cancer, metastatic non-small-cell lung cancer, and bladder cancer. It also participated in breast-cancer research through the I-SPY clinical-trial platform. The broader pipeline included rintodestrant, an oral selective estrogen receptor degrader for ER-positive, HER2-negative advanced breast cancer, and lerociclib, an oral CDK4/6 inhibitor intended for continuous dosing with less dose-limiting neutropenia than some alternatives. G1 also maintained a preclinical CDK2 inhibitor program. The company used licensing and collaboration agreements to expand development and commercialization. Boehringer Ingelheim received a role in co-promoting trilaciclib in the United States and Puerto Rico. Simcere Pharmaceuticals obtained rights for greater China. Pfizer supplied palbociclib for a clinical study involving rintodestrant. EQRx received rights to develop lerociclib in the United States, Europe, Japan, and other territories outside most of Asia-Pacific, while Genor Biopharma received Asia-Pacific rights. ARC Therapeutics licensed G1's preclinical CDK2 inhibitor program. In September 2020, G1 announced a chief executive transition: Mark Velleca was to step down on January 1, 2021, with Jack Bailey, a former senior GlaxoSmithKline pharmaceutical executive, succeeding him. In September 2024, Pharmacosmos completed its acquisition of G1 Therapeutics. That transaction moved the company from independent public-company status into the Pharmacosmos group and marked the latest major ownership change in G1's history.

• 2024

  Acquisition by Pharmacosmos completed

  [1]G1 Therapeuticsen.wikipedia.org

  Pharmacosmos completed its purchase of G1 Therapeutics, changing G1's ownership and corporate status.

• 2021

  Cosela approved by the FDA

  [1]G1 Therapeuticsen.wikipedia.org

  The FDA approved trilaciclib, marketed as Cosela, for reducing chemotherapy-induced myelosuppression in certain extensive-stage small-cell lung cancer patients.

• 2021

  Cosela included in NCCN guidelines

  [1]G1 Therapeuticsen.wikipedia.org

  NCCN guidance identified trilaciclib as an appropriate prophylactic option for reducing chemotherapy-induced myelosuppression in the relevant small-cell lung cancer treatment context.

• 2020

  Trilaciclib NDA submitted

  [1]G1 Therapeuticsen.wikipedia.org

  G1 submitted a New Drug Application for trilaciclib to the U.S. Food and Drug Administration, and the application received priority review.

• 2017

  Public-market listing

  [1]G1 Therapeuticsen.wikipedia.org

  G1 Therapeutics became publicly traded on Nasdaq under the symbol GTHX.

• 2008

  G1 Therapeutics founded

  [1]G1 Therapeuticsen.wikipedia.org

  Norman Sharpless and Kwok-Kin Wong co-founded G1 to develop small-molecule oncology medicines originating from research associated with Sharpless's laboratory at the University of North Carolina at Chapel Hill.

G1 Therapeutics positioned itself as an oncology biopharmaceutical company developing small-molecule medicines intended not only to treat tumors but also to protect patients from the damaging effects of chemotherapy. Its distinctive commercial and scientific proposition centered on myelopreservation through transient CDK4/6 inhibition, with Cosela serving as the principal marketed product.

• Oncology supportive care · 2021

  Cosela

  Cosela is the brand name for trilaciclib, a short-acting CDK4/6 inhibitor administered before certain chemotherapy regimens. It was developed to temporarily protect bone-marrow and immune precursor cells from chemotherapy-related damage, thereby reducing the frequency of chemotherapy-induced myelosuppression. The FDA approved Cosela in February 2021 for adults with extensive-stage small-cell lung cancer receiving specified chemotherapy. It is the principal approved and commercial product associated with G1 Therapeutics.

• CDK4/6 inhibitor

  Trilaciclib (G1T28)

  Trilaciclib is a small-molecule CDK4/6 inhibitor designed primarily for transient administration before chemotherapy. Its clinical-development rationale was myelopreservation: temporary cell-cycle inhibition in hematopoietic stem and progenitor cells could reduce chemotherapy-related marrow injury. G1 studied the candidate in small-cell lung cancer and additional solid tumors, including colorectal, breast, non-small-cell lung, and bladder cancers. Trilaciclib is marketed as Cosela in its approved indication.

• Selective estrogen receptor degrader

  Rintodestrant (G1T48)

  Rintodestrant is an oral selective estrogen receptor degrader developed for estrogen-receptor-positive, HER2-negative advanced breast cancer. G1 investigated it both as a monotherapy and in combination with palbociclib, a CDK4/6 inhibitor marketed by Pfizer as Ibrance. The program depended on clinical development rather than an approved commercial product in the supplied material.

• CDK4/6 inhibitor

  Lerociclib (G1T38)

  Lerociclib is an oral, selective CDK4/6 inhibitor. G1 characterized the program as potentially differentiated by a favorable safety profile and the possibility of continuous dosing with less dose-limiting neutropenia. Development and commercialization rights were licensed to EQRx for several global markets and to Genor Biopharma for the Asia-Pacific region, with the supplied material excluding Japan from the Asia-Pacific restriction.

• 2020Trilaciclib expanded access program

  United States

  G1 established an expanded-access program for eligible small-cell lung cancer patients while the FDA reviewed the trilaciclib application.

  Outcome. The FDA approved trilaciclib as Cosela in February 2021.

  Source

• 2024

  Accept acquisition by PharmacosmosM&A

  Background

  G1 remained an oncology-focused biopharmaceutical company with Cosela as its principal marketed product.

  Action taken

  Pharmacosmos completed its purchase of G1 Therapeutics.

  Aftermath

  G1 ceased to operate as an independent publicly traded company and became part of the Pharmacosmos group.

  Source

• 2020

  Submit trilaciclib for regulatory approvalProduct launch

  Background

  G1's lead candidate had generated clinical evidence in small-cell lung cancer for reducing chemotherapy-induced myelosuppression.

  Action taken

  The company submitted a New Drug Application to the FDA in June 2020. The application received priority review.

  Aftermath

  The FDA approved trilaciclib as Cosela on February 12, 2021.

  Source

• 2020

  Create an expanded-access route for trilaciclibStrategy

  Background

  Patients with small-cell lung cancer sought access to the investigational treatment while the FDA considered G1's application.

  Action taken

  G1 launched an expanded-access program in September 2020.

  Aftermath

  The program preceded commercial availability after regulatory approval of Cosela.

  Source

• 2020

  Broaden trilaciclib commercialization capabilitiesStrategy

  Background

  G1 was preparing to commercialize trilaciclib for small-cell lung cancer in the United States and Puerto Rico.

  Action taken

  The company entered a commercialization agreement with Boehringer Ingelheim to co-promote the product.

  Aftermath

  The agreement supported the commercial launch of Cosela after FDA approval.

  Source

• 2021.02.12

  Reported2021.02.13

  FDA approves COSELA[3]FDA批准COSELAfinance.yahoo.com

  G1 Therapeutics announced that the U.S. Food and Drug Administration approved COSELA (trilaciclib) for injection to decrease chemotherapy-induced myelosuppression in certain adult patients with extensive-stage small cell lung cancer.

Read more

1. 1G1 Therapeuticsen.wikipedia.org
2. 2G1 Therapeutics corporate informationg1therapeutics.com
3. 3FDA批准COSELAfinance.yahoo.com