Laboratory and clinical studies on sparfloxacin (SPFX)

The newly developed broad-spectrum fluoroquinolone, sparfloxacin (SPFX), was evaluated in vitro and in vivo in comparison with ciprofloxacin, ofloxacin, enoxacin and norfloxacin. The results were as follows ; 1. Antimicrobial activity : Minimal inhibitory concentrations (MIC_s) against 225 clinical isolates including 7 different species were determined by the microbroth dilution method. Sparfloxacin showed excellent antimicrobial activity against Gram-positive and negative bacteria. The MIC values of sparfloxacin for Gram-positive bacteria including MRSA were superior to those of the other quinolones tested. The MIC values of sparfloxacin for Gram-negative bacteria were comparable to those of ciprofloxacin and superior to those of ofloxacin, enoxacin and norfloxacin. The MIC value of sparfloxacin for Mycoplasma pneumoniae was superior to ofloxacin. 2. Sparfloxacin concentration in serum and sputum : Sparfloxacin was orally administered in a single dose of 200 mg or 300 mg to five patients with chronic lower respiratory diseases, and its concentrations in serum and sputum were measured at intervals by HPLC or bioassay. The mean peak concentrations of sparfloxacin in the serum and sputum of patients administered 200 mg were 0.54 and 0.88 μg/ml, respectively, and those of patients administered 300 mg were 2.59 and 2.67 μg/ml, respectively. From these data, it was suggested that sparfloxacin had good penetration into the lung. 3. Clinical efficacy and adverse reactions : Thirty-five patients with respiratory tract infections were treated with sparfloxacin, and the overall efficacy ratio was 85.7% (excellent in 8 cases, good in 22, fair in 3, and poor in 2). As the side effect, heart burn in one case was observed. Although the eosinophilia in 3 cases, the elevation of GOT and GPT in 2 cases, the elevation of GPT and LDH in 1, and the elevation of amylase in 1 were observed as laboratory abnormal findings, they were mild and transient, and improved rapidly after completion of sparfloxacin treatment.