Abstract
PC-904 (sodium (2S, 5R, 6R)-6-[(R)-2-(4-hydroxy-1, 5-naphthyridine-3-carboxamido)-2-phenylacetamido]-3, 3-dimethy1-7-oxo-4-thia-1-azabicyclo [3. 2. 0.] heptane-2-carboxylate) is a new semisynthetic penicillin. We studied its antibacterial activity against some clinically isolated bacteria and its clinical effectiveness.
The results obtained were as follows.
1) MIC values of PC-904 against 7 strains E. coli out of 10 were distributed 0.9 to 12.5 μg/mI. Those against Ps. aeruginosa 10 strains and Prot. mirabilis 6 strains were all less than 3.12 μg/ml. Three of the 5 strains of Kleb. pneumoniae and all of the 3 strains of Serratia marcescens were resistant to PC-904.
2) The antibacterial activities of PC-904 against Ps. aeruginosa and Prot. mirabilis were superior to CBPC and GM. Those against E. coli were superior to CBPC but inferior to GM:
3) PC-904 was administered intravenously to 9 patients (urinary infection 6 cases and pulmonary infection 3 cases) at daily dose 2.0-4.0 g, and good responses were obtained in 7 cases.
4) As a side effect, the transient falling of arterior blood pressure after intravenous injection was observed in 1 patient.
