Medicilon Assisted Regor Therapeutics Group's New-generation Tumor-targeting Inhibitor RGT-419B Getting Approved for Clinical Use

On December 28, 2021, the new generation of CDK2/4/6 small molecule inhibitor RGT-419B independently developed by Regor Therapeutics Group (Regor) was approved by the U.S. Food and Drug Administration (FDA).  It is expected to improve the safety of currently approved CDK4/6 inhibitors and overcome resistance to these inhibitors.

As a collaborative partner of Regor, Shanghai Medicilon Inc. (Medicilon) provided RGT-419B with a toxicological DRF test that complies with GLP specifications to accelerate the project's R&D process.

RGT-419B has an optimized kinase activity profile, which is expected to improve the safety of currently approved CDK4/6 inhibitors and overcome resistance to these inhibitors.  These inhibitors are used in combination with endocrine therapy to treat patients with premenopausal/postmenopausal hormone receptor positive (HR+) and human epidermal growth factor receptor 2 negative (HER2-) advanced or metastatic breast cancer.

In the cell model experiments, RGT-419B showed single-drug activity, and compared with abemaciclib and palbociclib, it had a greater inhibitory effect on the growth of ER+ tumor cells.  In ER+ breast cancer cells resistant to currently approved CDK4/6 inhibitors, RGT-419B showed complete inhibition of cancer cell proliferation.  In these experiments, when RGT-419B is used in combination with selective estrogen receptor degradants or PI3K signaling pathway inhibitors, its inhibitory effect on tumor cells is further enhanced.

In the development of RGT-419B, Medicilon relied on 13 years of GLP good operating experience and 18 years of toxicological research experience to provide necessary and key toxicological test data for RGT-419B.  Efficient service and high-quality data helped Regor to increase the successful rate of declaration and reduce the cost of new drug research and development.

Medicilon congratulates Regor on the clinical approval of RGT-419B, and expects this new drug with great potential to benefit more cancer patients as soon as possible.  Medicilon also congratulates Regor on its milestone progress and successfully entering the field of tumor treatment.  Medicilon will continue to uphold the "innovation-driven, quality first" service concept to help more new drugs develop faster and to help more innovative biopharmaceutical companies to go global!