Posaconazole

Posaconazole is a triazole antifungal drug marketed in the United States, the European Union, and in other countries by Schering-Plough under the trade name Noxafil. In Canada, posaconazole is marketed by Schering-Plough under the trade name Posanol.

Pharmacology

Mode of action

Posaconazole works by disrupting the close packing of acyl chains of phospholipids, impairing the functions of certain membrane-bound enzyme systems such as ATPase and enzymes of the electron transport system, thus inhibiting growth of the fungi. It does this by blocking the synthesis of ergosterol by inhibiting of the enzyme lanosterol 14α-demethylase and accumulation of methylated sterol precursors. Posaconazole is significantly more potent at inhibiting 14-alpha demethylase than itraconazole.

Microbiology

Posaconazole is active against the following microorganisms:

Pharmacokinetics

Posaconazole is absorbed within three to five hours. It is predominately eliminated through the liver, and has a half life of about 35 hours. Oral administration of posaconazole taken with a high-fat meal exceeds 90% bioavailability and increases the concentration by four times compared to fasting state.