Cidara Therapeutics, Inc., a San Deigo-based biotechnology company developing novel anti-infectives and immunotherapies to treat fungal and other infections, announced that the U.S. FDA has granted orphan drug designation to its antifungal drug candidate, CD101 IV, for the treatment of candidemia and invasive candidiasis.    Candida is the leading cause of bloodstream infections within U.S. hospitals.  Systemic Candida infections are considered to be serious and life-threatening, with up to 47 percent mortality.  Cidara is developing CD101 IV for the treatment and prevention of serious fungal infections that are associated with high mortality rates and rising drug resistance.  Current standards of care for invasive fungal infections, including azoles, have multiple limitations including drug interactions and dose-limiting toxicities.  First-generation echinocandins require daily IV dosing, limiting their use primarily to the inpatient setting.