Background:

Raltegravir, formerly named MK-0518, is an HIV-1 integrase strand transfer inhibitor which has been shown to have activity against multidrug-resistant HIV-1 and both CCR5-trophic and CXCR4-trophic HIV-1 in vitro. Structural modifications on these molecules are made in order to maximize potency as HIV-integrase inhibitors against the wild type virus, a selection of mutants, and optimize the selectivity, pharmacokinetic, and metabolic profiles in preclinical species. Raltegravir derives from the evolution of 5,6-dihydroxypyrimidine-4-carboxamides and N-methyl-4-hydroxypyrimidinone-carboxamides. It has been shown to have potent antiretroviral effects, with a mean decrease from baseline in HIV-1 RNA concentrations of about 2 log10 copies per mL after 10 days of monotherapy.

Reference

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