Laboratory and clinical studies on biapenem

Abstract

A newly developed broad-spectrum carbapenem, biapenem (BIPM), was evaluated in vitro and in vivo. The results were as follows;
1. Antimicrobial activity: Minimal inhibitory concentrations (MICs) against 515 clinical isolates including 16 different species were determined by the microbroth dilution method and were compared with those of imipenem, cefuzonam, ceftazidime and piperacillin. BIPM showed exellent antimicrobial activity against gram-positive and negative bacteria.
bacteria. 2. BIPM concentrations in plasma and sputum: A patient with acute bronchitis was given 600mg of BIPM intravenously and its concentrations in plasma and sputum were measured at intervals using bioassay. A peak concentration in plasma was observed immediately after the infusion, and achieved 36.8μg/ml. Whereas, a peak sputum level of 3.92μg/ml was observed 2 3 hours after the infusion. This suggested that BIPM has rapid and good penetration into the lung.
3. Clinical efficacy and adverse reaction: Thirty patients with respiratory tract infections and urinary tract infections were treated with BIPM. An overall efficacy rate was 96.2%(excellent in 9 cases, good in 16, poor in 1, and unevaluable 4). Diarrhea and abdominal discomfort were observed in 3 cases as the adverse reaction. As the laboratory abnormal findings, elevation of GOT and/or GPT in 3 cases, eosinophilia in 1 case and hyponatremia in 1 case were observed. All of these were mild and improved rapidly after completion of BIPM, indicating that BIPM is a quite safety agent. From these results, BIPM was thought to be highly useful for the treatment of respiratory tract infections and urinary tract infections.