GB491 + letrozole

GB491 + letrozole is a combination therapy under investigation for the treatment of hormone receptor-positive breast cancer in postmenopausal women. Letrozole is a third-generation nonsteroidal aromatase inhibitor that works by competitively inhibiting the aromatase enzyme (CYP19A1), thereby reducing estrogen biosynthesis in all tissues. This reduction in estrogen levels slows or stops the growth of certain types of breast cancer cells that require estrogen to grow[1][3][6]. Letrozole is approved for use as adjuvant and first-line therapy in postmenopausal women with hormone receptor-positive early or advanced breast cancer[7]. GB491 (also known as lerociclib) is an investigational oral cyclin-dependent kinase 4/6 (CDK4/6) inhibitor developed to be used in combination with endocrine therapies such as letrozole for enhanced antitumor activity. The combination aims to provide synergistic inhibition of tumor cell proliferation by targeting both hormonal and cell cycle pathways.

Other names

CGS 20267CGS20267CGS-20267