In April 2011, Mpex Pharmaceuticals was acquired by Axcan. The firm had functioned ias a clinical stage biopharmaceutical company developing important new therapies to combat the growing issue of antibiotic resistance. While much of the attention in the medical community has been focused on resistance in gram-positive pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), increasing antibiotic resistance in gram-negative organisms such as Pseudomonas aeruginosa represents a significant threat, with far fewer treatment options available. Ccurrent focus is on improving treatments for gram-negative pathogens. Mpex is using its deep understanding of the sources of antibiotic resistance to design innovative approaches for overcoming bacterial escape mechanisms. These approaches include proprietary antibiotic formulations, novel pharmacokinetic and pharmacodynamic development strategies, and newly discovered compounds that potentiate the activity of antimicrobial agents. By combining these approaches with proven existing antibiotics, Mpex's products under development can potentially overcome or directly inhibit bacterial resistance. Mpex's lead product candidate, MP-376, is a novel aerosol formulation of a powerful antibiotic that has been widely used in patients for over a decade. MP-376 is currently in Phase 1b clinical trials for the treatment of chronic infections due to Pseudomonas aeruginosa in patients with cystic fibrosis. This novel formulation coupled with a high-efficiency nebulizer is projected to enable delivery of drug directly to the lungs to produce greater antibacterial effects with a lower propensity for drug resistance. The Company is also a world leader in the discovery and development of inhibitors of bacterial multi-drug resistant efflux pumps. Efflux pumps have been shown to be a primary source of drug resistance in many gram-negative pathogens. Mpex has identified a number of lead efflux pump inhibitors (EPIs) for optimization, and has developed an extensive intellectual property portfolio. Mpex scientists have shown in preclinical studies that EPIs can restore the potency of numerous antibiotics against drug-resistant gram-negative organisms. These novel EPI compounds are being further profiled in preclinical studies, and may be candidates for clinical development in combination with antibiotics previously proven to be safe and effective in a variety of clinical indications