Caspofungin acetate (Cancidas) is the first of a new class of antifungal drugs (echinocandins). It works by interfering with the mechanism a fungus uses to build its cell wall which is quite different to all other antifungal drugs which mostly work by inhibiting cell membrane synthesis. This makes it particularly useful when other drugs have been tried and failed as it attacks a different target - there would be little point in using an antifungal which tried to 'hit' the same target when inhibiting that target molecule has already failed.
As with most drugs approval is often granted in stages as research confirms or denies the efficacy of that drug in different patient groups. Caspofungin has been approved for some time for adult patients that had been treated and failed with other antifungals, but this new approval now allows use in children from 3 months to 17 years of age for the following conditions:
invasive aspergillosis in patients refractory or intolerant of other therapies. It also may be used as empiric therapy for presumed fungus infection in patients with fever and neutropenia.Caspofungin was found to be superior to established drugs in particular circumstances in children in two separate papers and was thus granted approval for the US by the FDA.