Patients simultaneously receiving inhalative antibiotics and azithromycin (n=12) revealed lower baseline levels in all mediators measured except TIMP-1 and MMP-9 and significant lower levels in IL-6 and NE during stable phase and reduced NE levels during exacerbation compared to CF patients only receiving inhalative antibiotics (n=8). This evidence concerns the gene MMP9 and cystic fibrosis.