Laboratory and Clinical Evaluation of DQ-2556

The newly developed cephalosporin antibiotic agent, DQ-2556, was evaluated in vitro and in vivo. The results were as follows; 1. Antimicrobial activity: Minimal inhibitory concentrations (MICs) against 480 clinical isolates including 15 different species were determined and compared with those of cefotiam, ceftizoxime, ceftazidime and cefzonam. DQ-2556 showed excellent antimicrobial activity against gram-positive bacteria including methicillin-resistant Staphylococcus aureus and gram-negative bacteria. The MICs of DQ-2556 were almost equal to those of the other cephalosporins or were lower. 2. DQ-2556 concentrations in serum and sputum: A patient with diffuse panbronchiolitis was given 1 g of DQ-2556 intravenously and its concentrations in serum and sputum were measured at intervals by HPLC. A peak concentration in serum was observed immediately after the infusion, and reached 69.7 μg/ml. A peak sputum level of 1.8μg/ml was observed 3~4 hours after the infusion. This suggests that DQ-2556 has rapid and good penetration into the lung. 3. Clinical efficacy and adverse reactions: Fourteen patients with respiratory tract infections were treated with DQ-2556. An overall efficacy rate was 78.6% (excellent in 1 case, good in 10, fair in 2, poor in 1). Fever and rash were observed in 1 case as an adverse reaction. With regards to abnormal laboratory findings, neutrocytophilia and elevation of LDH in 1 case, and elevation of GOT and GPT in another case were observed. All of these were mild and improved rapidly after completion of DQ-2556, indicating that DQ-2556 is a safe agent.