Reduced toxicity of a new formulation--peplomycin adsorbed on activated carbon particles--in mice

We studied the acute toxicity and pathological effects of peplomycin adsorbed on fine activated carbon particles (PEP-CH) injected subcutaneously in mice. The 50% lethal dose value was 41.2 mg/kg in terms of peplomycin, which was 1.52 times that of the peplomycin aqueous solution (PEP-AQ) of 27.1 mg/kg. Deaths occurred from 5 to 31 days after administration of PEP-CH and from 5 to 22 days after administration of PEP-AQ solution. These figures are remarkably different from another report in which the mice given PEP-AQ died within 10 days.