The acetate salt of an antimycotic echinocandin lipopeptide, semisynthetically derived from a fermentation product of the fungus Glarea lozoyensis. Caspofungin inhibits 1,3-beta-glucan synthase, resulting in decreased synthesis of beta(1,3)-D-glucan (an essential component of the fungal cell wall), weakening of the fungal cell wall, and fungal cell wall rupture. This agent is active against Aspergillus and Candida species. OR A study that compares two groups of people: those with the disease or condition under study (cases) and a very similar group of people who do not have the disease or condition (controls). Researchers study the medical and lifestyle histories of the people in each group to learn what factors may be associated with the disease or condition. For example, one group may have been exposed to a particular substance that the other was not. Also called retrospective study.