Comparative activities of the beta-lactamase inhibitors YTR 830, sodium clavulanate, and sulbactam combined with amoxicillin or ampicillin.

YTR 830, a new beta-lactamase inhibitor, was compared with clavulanic acid and sulbactam against aminopenicillin-resistant clinical isolates. At a concentration of 8 micrograms/ml, YTR 830 was as effective as clavulanate or sulbactam in reducing the aminopenicillin MICs. Combined with amoxicillin, YTR 830 is a potentially useful agent for therapy of many bacterial infections.