Anidulafungin is a semisynthetic echinocandin used as an antifungal drug. It has proven efficacy against esophageal candidiasis, but its main use will probably be in invasive Candida infection; it may also have application in treating invasive Aspergillus infection. It is a member of the class of antifungal drugs known as the echinocandins; its mechanism of action is by inhibition of (1→3)-β-D-glucan synthase, an enzyme important to the synthesis of the fungal cell wall. Anidulafungin significantly differs from other antifungals in that it undergoes chemical degradation to inactive forms at body pH and temperature. Because it does not rely on enzymatic degradation or hepatic or renal excretion, the drug is safe to use in patients with any degree of hepatic or renal impairment. Anidulafungin is manufactured via semi-synthesis. The starting material is echinocandin B, the fermentation product of Aspergillus nidulans, followed by three synthetic steps.