[Review [new antibiotics series III]: micronomicin (author's transl)]

Micronomicin is a new aminoglycosidic antibiotic discovered and developed by Kyowa Hakko Kogyo Co., Ltd. It is produced by Micromonospora sagamiensis var. nonreducans. Investigation of micronomicin performed in 134 research facilities in Japan led to the following results. 1) Micronomicin showed a broad antibacterial spectrum against Gram positive and Gram negative bacteria. 2) In susceptibility tests of clinical isolates, micronomicin was almost similarly active to GM. 3) Bactericidal activity of micronomicin against Pseudomonas aeruginosa and E. coli was higher than those of TOB and DKB. 4) Micronomicin showed a synergistic antibacterial activity against Pseudomonas aeruginosa and E. coli with CBPC and SBPC. 5) The therapeutic activity of micronomicin in mice infected with Pseudomonas aeruginosa and Serratia sp. was in high correlation with in vitro antibacterial activity similarly to that of GM. 6) Micronomicin was confirmed to be stable against aminoglycoside 6'-acetyltransferase of Pseudomonas aeruginosa and to be not inactivated. 7) Pharmacokinetics of micronomicin was almost similar to those of GM with respect to the concentrations in the serum, urine and tissues. 8) Ototoxicity of micronomicin in guinea pigs was found to be approximately four times less than that of GM. 9) Nephrotoxicity of micronomicin in rabbits was estimated to be less than those of GM and DKB. In rats, nephrotoxicity of micronomicin was approximately 4 times less than that of GM. 10) Micronomicin was effective on 964 cases out of 1,469 cases from 127 research facilities in Japan (65.6%), suggesting its favorable activity against respiratory tract infections and against urinary tract infections. 11) Side effects with the drug were observed in 43 cases out of 1,532 cases (2.81%). Abnormalities in laboratory findings were also recognized, but transient without severe cases. 12) In conclusion, micronomicin is a favorable drug having lesser ototoxicity and nephrotoxicity as well as antibacterial and bactericidal activity of aminoglycosidic antibiotics usually used.