Discontinued drugs in 2008: anti-infectives.

Of the many drugs dropped from development in 2008, 27 were under development for therapy or prophylaxis of infectious diseases. The majority of these were for diseases of viral etiology (15 agents), while nine were antibacterials and the remaining three were directed against fungal and protozoan pathogens. The antiviral agents were primarily against HIV and hepatitis C virus, together with agents against hepatitis B virus and West Nile virus. The antibacterial agents were mostly from known classes (carbapenems, fluoroquinolones, oxazolidinones), but also included several novel compounds and approaches. With regard to drug type, 19 were small-molecule therapeutics, seven were biologics comprising five vaccines and two antibodies, and one was a high-molecular-weight polymer. Each of these agents is briefly reviewed and the reasons for failure are discussed.