rgt-419b + hormonal therapy

RGT-419B + hormonal therapy is an investigational drug combination currently being evaluated in clinical trials for **hormone receptor positive, HER2-negative advanced or metastatic breast cancer**. The combination consists of **RGT-419B**, a next-generation, orally administered small molecule inhibitor with selectivity for **Cyclin-dependent kinase 4 (CDK4)** and weaker inhibitory activity against **CDK2** and **CDK6**, alongside standard hormonal (endocrine) therapy for breast cancer, such as fulvestrant or aromatase inhibitors. RGT-419B is developed to overcome resistance to prior CDK4/6 inhibitors in patients previously treated with endocrine therapy, leveraging its differentiated activity profile. The primary indication under investigation is advanced breast cancer refractory to CDK4/6 inhibitors and endocrine therapies. RGT-419B shows promising partial responses and prolonged disease control in early-phase trials, with favorable safety characteristics (low grade 3+ toxicities). Current studies are being conducted as monotherapy as well as in combination with hormonal therapy (endocrine therapy) with the aim to improve outcomes in heavily pretreated HR+/HER2- breast cancer. Clinical trials are ongoing in the United States and China.

Other names

RGT-419B + hormonal therapy