C57BL/6 male mice (8 to 10 weeks of age) were infected i.t. with 1 x 10⁶ CFUs of MDR-RP73 embedded in agar beads. Mice (11 per group of treatment) were treated by gavage with roflumilast (5 mg/Kg/day) or placebo (4,4% DMSO in saline), with the starting dose administered two hours before infection and the last 2 hours before sacrifice. Five days post infection, mice were sacrificed, BALF was collected and mouse lungs were recovered, homogenized and plated to determine the bacterial load. Counts of total cells, neutrophils and macrophages, as well as levels of cytokines and total protein were evaluated in BALF. Statistical differences between Roflumilast- and vehicle-treated animals were analysed by Student-t test.