In vitro activity: Moxifloxacin exerts its effects by trapping a DNA drug enzyme complex and specifically inhibiting ATP-dependent enzymes topoisomerase II (DNA gyrase) and topoisomerase IV. Moxifloxacin shows in-vitro potency against M. tuberculosis H37Rv with MIC of 0.177 μg/mL. Moxifloxacin has broad Grampositive and Gram-negative activity. Moxifloxacin shows in vitro and clinical efficacy against Staphylococcus aureus, Streptococcus pneumoniae, Str. pyogenes, Haemophilus influenzae, H. parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydia pneumoniae and Mycoplasma pneumoniae. Moxifloxacin has activity against mycobacteria in addition to M. tuberculosis; Moxifloxacin is more active against M. kansasii than M. aviumcomplex: specifically MIC90 for M. avium > M. intracellulare > M. kansasii at 4, 2 and 2 μg/mL, respectively. MIC90 for M. chelonae > M. fortuitum at 16 and 0.5 μg/mL, respectively.

Cell Assay: Moxifloxacin (Hydrochloride) is a synthetic fluoroquinolone antibiotic agent. Antibacterial Moxifloxacin is an extended-spectrum fluoroquinolone which has improved coverage against gram-positive cocci and atypical pathogens compared with older fluoroquinolone agents, while retaining good activity against gram-negative bacteria. The antibacterial spectrum of moxifloxacin includes all major upper and lower respiratory tract pathogens; it is one of the most active fluoroquinolones against pneumococci, including penicillin- and macrolide-resistant strains. Moxifloxacin has limited phototoxic potential. In clinical trials, moxifloxacin had clinical success rates of 88-97% and bacteriologic eradication rates of 90-97%. Moxifloxacin is a safe and effective antimicrobial that will be useful for treating acute sinusitis, acute bacterial exacerbations of chronic bronchitis, and community-acquired pneumonia. Moxifloxacin possibly stimulates lipid peroxidation and enhances phagocytosis, as depicted by MDA production and survival prolongation, without being toxic as depicted by white blood cell count. Clinical indications: Abdominal abscess; Acute bronchitis; Acute sinusitis; Bacterial infection Toxicity: Symptoms of overdose include CNS and gastrointestinal effects such as decreased activity, somnolence, tremor, convulsions, vomiting, and diarrhea. The minimal lethal intravenous dose in mice and rats is 100 mg/kg.