In this article, we will discuss Enzalutamide (Mechanism of Action). So, let’s get started.
Enzalutamide is an androgen receptor inhibitor. The chemical name is 4-{3-[4-cyano-3-(trifluoromethyl)phenyl]-5,5-dimethyl-4-oxo-2-sulfanylideneimidazolidin-1-yl}-2-fluoro-N-methylbenzamide. The molecular weight is 464.44 and molecular formula is C21H16F4N4O2S.
Enzalutamide (XTANDI®) is a white crystalline non-hygroscopic solid. It is practically insoluble in water.
Enzalutamide (XTANDI®) is provided as liquid-filled soft gelatin capsules for oral administration. Each capsule contains 40 mg of enzalutamide as a solution in caprylocaproyl polyoxylglycerides. The inactive ingredients are caprylocaproyl
polyoxylglycerides, butylated hydroxyanisole, butylated hydroxytoluene, gelatin, sorbitol sorbitan solution, glycerin, purified water, titanium dioxide, and black iron oxide.
Mechanism of Action
Enzalutamide is an androgen receptor inhibitor that acts on different steps in the androgen receptor signaling pathway. Enzalutamide has been shown to competitively inhibit androgen binding to androgen receptors, and consequently, inhibits nuclear translocation of androgen receptors and their interaction with DNA. A major metabolite, N-desmethyl enzalutamide, exhibited similar in vitro activity to enzalutamide. Enzalutamide decreased proliferation and induced cell death of prostate cancer cells in vitro, and decreased tumor volume in a mouse prostate cancer xenograft model.
Pharmacodynamics
Cardiac Electrophysiology
The effect of enzalutamide 160 mg/day at steady-state on the QTc interval was evaluated in 796 patients with metastatic CRPC. No large difference (i.e-greater than 20 ms) was observed between the mean QTc interval change from baseline in patients treated with Enzalutamide (XTANDI®) and that in patients treated with placebo, based on the Fridericia correction method. However, small increases in the mean QTc interval (i.e., less than 10 ms) due to enzalutamide cannot be excluded due to limitations of the study design.