Apalcillin

Apalcillin (PC-904) in combination with Ro 48-1220, a penam sulfone β-lactamase inhibitor, demonstrated broad-spectrum activity against gram-negative aerobic and anaerobic bacteria, excluding Klebsiella oxytoca. It exhibited potent activity against β-lactamase-producing Moraxella catarrhalis, Haemophilus influenzae, and Neisseria gonorrhoeae, with effective MICs (11 μg/mL). The combination also inhibited Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Acinetobacter species at low MICs (0.25 to 4 μg/mL). However, its efficacy against oxacillin-resistant staphylococci and certain gram-positive organisms was limited. Apalcillin/Ro 48-1220 showed comparable efficacy to piperacillin/tazobactam against some extended-spectrum β-lactamase-producing Escherichia coli but was less effective against SHV-type β-lactamases^[1].