Pirbenicillin-a semi-synthetic penicillin with antipseudomonal activity

Abstract

Pirbenidihin, a semi-synthetic penicillin, structurally related to ampicillin, was investigated as to its in vitro activity. The drug was found to exhibit a higher degree of activity against Pseudomonas aeruginosa, being approximately eight times more active than carbenicillin and four times more active than ticarcillin. The new drug was about fourfold more active than carbenicillin against other Entero bacteriaceae with the exception of Proteus spp. The drug is somewhat more stable in serum than carbenicfflin. Pirbenicillin does not appear to inactivate gentamicin as rapidly as carbenicillin.