Clinical outcomes from major clinical trials in CF
| Participants | Absolute change in ppFEV1 from baseline | Change in exacerbation rate | |
| DNase (Fuchs et al. [52], 1994) | ≥5 years ppFVC >40% | 5.8% (24 weeks) | 28% reduction |
| Nebulised tobramycin (Ramsey et al. [53], 1999) | ≥6 years ppFEV1 25–75% | 5% (20 weeks)# | 26% reduction |
| Azithromycin (Saiman et al. [54], 2003) | ≥6 years ppFEV1 ≥30% | 4.4% | Hazard ratio 0.65 |
| Hypertonic saline (Elkins et al. [55], 2006) | ≥6 years ppFEV1 ≥40% | 3.2% (4 to 48 weeks) | 56% reduction |
| Nebulised aztreonam (McCoy et al. [56], 2008) | ≥6 years ppFEV1 25–75% | 6.3% (4 weeks) | 45% reduction |
| Nebulised levofloxacin (Elborn et al. [57], 2015) | ≥12 years ppFEV1 25–85% | 0.1% (4 weeks) | 10.5% reduction |
| Ivacaftor (Ramsey et al. [11], 2011) | ≥12 years ppFEV1 40–90% At least one Gly551Asp | 10.1% (4 weeks) | 55% reduction |
| Elexacaftor/tezacaftor/ivacaftor (Middleton et al. [29], 2019) | ≥12 years ppFEV1 40–90% Phe508del MF | 13.8% (4 weeks) | 63% reduction |
ppFEV1: percentage predicted forced expiratory volume in 1 s; ppFVC: percentage predicted forced vital capacity. #: approximated using data from supplementary appendix on absolute change in ppFEV1 rather than change from baseline.