Combination of caspofungin with inhibitors of the calcineurin pathway attenuates growth in vitro in Aspergillus species

Work in Saccharomyces cerevisiae and Cryptococcus neoformans suggests that caspofungin could interact with the calcineurin pathway. We examined the in vitro interaction of caspofungin with calcineurin inhibitors (FK506, cyclosporin, FK520 and L685,818) and the TOR inhibitor rapamycin in 13 isolates of Aspergillus species. Caspofungin activity was enhanced by calcineurin/TOR inhibitors for all Aspergillus isolates studied. Further investigation of this pathway is warranted.