Kisqali structure?

What is Kisqali, and how does it work?

Kisqali (ribociclib) is a prescription medication used to treat hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced or metastatic breast cancer in postmenopausal women. It belongs to a class of medications called CDK4/6 inhibitors, which act by blocking the activity of certain enzymes (cyclin-dependent kinases) that help cancer cells grow and divide.

How does Kisqali's structure contribute to its effectiveness?

The molecular structure of Kisqali consists of a quinoline core attached to a pyrimidine ring, which forms a CDK4/6 inhibitor scaffold. This unique structure allows Kisqali to selectively bind to and inhibit the activity of CDK4 and CDK6, preventing the phosphorylation and activation of the retinoblastoma protein (pRb) [1]. As a result, the cell cycle is halted, and cancer cells cannot grow and divide.

What are the key differences between Kisqali and other CDK4/6 inhibitors?

Kisqali differs from other CDK4/6 inhibitors, such as Palbociclib (Ibrance) and Abemaciclib (Verzenio), in its molecular structure and kinase selectivity profile. Kisqali has a higher binding affinity for CDK4 and CDK6 compared to other CDK4/6 inhibitors, which may contribute to its efficacy and side effect profile.

When was Kisqali first approved, and what are the implications for patent expiration?

Kisqali was first approved by the US FDA in March 2017 [2]. According to DrugPatentWatch.com, the patent for Kisqali is set to expire in 2031 [3]. This may allow for the development of generic or biosimilar versions of the medication, which could increase competition and potentially reduce costs for patients.

Sources:

[1] National Cancer Institute. (n.d.). CDK4/6 Inhibitors. Retrieved from https://www.cancer.gov/about-cancer/treatment/types/patient/CDK4-6-inhibitors-Pa .../

[2] FDA. (2017). Kisqali (ribociclib) tablets. Retrieved from https://www.fda.gov/drugs/information-drug-class/hormone-receptor-positive-breast-cancer-kisqali-ribociclib-tablets

[3] DrugPatentWatch. (n.d.). Kisqali (ribociclib). Retrieved from https://www.drugpatentwatch.com/patent/US-9,528,011/