Antifungal Drug Discovery, Six New Molecules Patented After 10 Years of Feast:Why do we Need New Patented Drugs Apart from New Strategies?

Abstract

After 10 years absence (between 1990-1999) of new antifungal agents and intensive research being introduced into clinical practice, 3 new azoles (Voriconazole - Pfizer, Posaconazole - Schering-Plough, Ravuconazole - Bristol-Myers Squibb) and 3 new echinocandins (Caspofungin - MSD, Anidulafungin - Astellas-Pfizer, Micafungin - Fujisawa) were patented. The question raises if we really need 6 new antifungal agents in such a short time? Perhaps, they are not here because we need them all, but because of at least fifteen years effort of many groups of investigators who successfully discovered, proved and introduced these agents to the drug market. Voriconazole (2000), Posaconazole (2005), Ravuconazole (2007) from the group of azoles; and Caspofungin (2002), Anidulafungin (2004) and Micafungin (2006) from the group of echinocandins, with unique mode(s) of action (cell wall synthesis inhibition) different from polyens, azoles, antimetabolites and new monoclonal antifungal antibody (Mycograb), were approved and introduced to the clinical practice. This paper contains some useful information regarding the recent patents on antifungal drug discovery, their current position in the strategy of treatment of invasive fungal infections is briefly reviewed.