Amphotericin B is an antibiotic produced by a species of Streptomyces. It appears to have no important antibacterial properties, but possesses highly significant activity against those yeast-like fungi which produce deep mycotic infection in man. Table 1 contains the in vitro sensitivities of the major producers of deep mycotic infection in man as determined by various investigators.1-3 Our own findings, on Sabouraud's dextrose agar at pH 7, are indicated in the Table.
Studies in experimental animals2,3 have indicated a good correlation between in vivo effectiveness and in vitro sensitivity to amphotericin B. Animal toxicity studies carried out by the Squibb Institute for Medical Research indicated that amphotericin B had a therapeutic index sufficient to justify clinical trial in human mycotic infections. Several reports 4-6 of its use in histoplasmosis and cryptococcosis have already appeared in the American literature.
Routes of Administration and Toxicity
The insolubility of crystalline or