The Phase I Clinical trial units, through individual contracts with academic centers and organizations that provide resources for the development and implementation of Phase I trials, will investigate therapeutic agents for the treatment of infectious diseases. The units will investigate therapeutic agents for viral (other than HIV), bacterial, fungal and parasitic diseases including NIAID priority biodefense pathogens and emerging and re-emerging diseases. The Phase I units provide an invaluable vehicle for the investigation of new therapeutic and immunomodulatory agents for the treatment of infectious disease.