There is provided 1-cyclopropyl-8-methyl-7-[5-methyl-6-(methylamino)-3-pyridinyl]-4-oxo-1,4-dihydro-3-quinolinecarboxylic acid selected from the group consistingofcitrate, hemi-fumarate, maleate, L-tartrate, mesylate, hydrochloride, hydrate,pharmaceutical composition comprising same and uses thereof for the treatmentorprevention of bacterial infections.