EUDRAGIT E100 POTENTIATES ACTIVITY OF OFLOXACIN AGAINST FQ-RESISTANT Pseudomonas aeruginosa

ROMERO, VERÓNICA L; MANZO, RUBEN H.; ALOVERO, FABIANA L.

Tandil, Bs. As.

Congreso; 40° Reunion Anual de Sociedad Argentina de Farmacología Experimental (SAFE),; 2008

Sociedad Argentina de Farmacología Experimental

Fluoroquinolones (FQs) resistance is a clinically significant issue. Efforts to improve the efficacy of existing FQs could be an alternative to restrict the development of FQ-resistant bacteria prolonging their future utility. Eudragit E100 (Eu) is a cationic polyelectrolyte able to react with the acidic group of OFLOXACIN yielding Eu-OFLOx complexes where OFLO neutralizes 20-50% of the basic groups of Eu. The addition of a second counterion (Cl-) turns the complexes water soluble giving clear dispersions (Eu-Cl50-OFLOx) with positive electrokinetic potential () and pHs 6.4-6.5. The activity against FQ-R P.aeruginosa was enhanced exhibiting MICs two or four-fold lower than free OFLO and improved bactericidal effect. Eu-Cl50 without OFLO exhibits an initial antibacterial effect reversible along the time while Eu-Cl50-OFLOx exhibits enhanced effect leading complete bacterial eradication at concentrations or time assays where free OFLO does not show it. This behaviour could be attributed to the improved drugbacterial cell interaction, topic in which the high of Eu- Cl50-OFLOx could play a preponderant role.