Background:

Ritonavir, previously known as ABT-538, is a potent inhibitor of human immunodeficiency virus type 1 (HIV-1) protease that exhibits potent in vitro inhibition against HIV-1 strain as well as HIV-2 strain with 50% effective concentration EC₅₀values of 0.022 μM and 0.16 μM respectively. Ritonavir binds to the HIV-1 protease inactivating its function to cleave the Gag and Gag-Pol polyproteins into the core proteins and viral enzymes, which results in the formation of noninfectious viral particles. X-ray crystallographic analysis reveals a hydrophobic cluster between the isopropyl substituent on the P3 thiazolyl group of ritonavir and the side chains of Pro-81 and Val-82 of HIV-1 protease within the complex of ritonavir/HIV-1 protease.

Reference

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