Mepartricin, a new semisynthetic heptene, was given for systemic Candida infections to 11 immunocompromised patients. All patients were undergoing bone marrow transplantation or treatment with antilymphocytic globulin: 6 had acute leukemia, 4 aplastic anemia and 1 had Wiskott-Aldrich syndrome. In all patients systemic Candida infection was diagnosed on the basis of fungemia or positive cultures from at least three different sites, two of which were outside the gut. Mepartricin was given intravenously as a slow drip, at the dose of 100-700 U/kg/day for a total of 198 patient-days (range 9-36, mean +/- SD 18 +/- 8). Patients had to be premedicated with steroids and antihistamines to avoid reactions such as chills and fever. The treatment was well tolerated in all patients, and renal function tests were unchanged during therapy. There was a complete resolution of the fungal infection in 10 of the 11 patients.