Rethinking Early Airway Clearence Therapies

Health outcomes among people with cystic fibrosis (CF) have been steadily improving for decades through guideline-directed multi-disciplinary clinical care models, expanding CF-specific therapies, and, most recently, the advent of highly effective modulator therapies (HEMT). Chronic therapies such as hypertonic saline (HS) and dornase alfa (DA) were associated with improved outcomes in the pre-modulator era but are also burdensome and costly. Now that almost 90% of the North American CF population is being treated with elexacaftor/tezacaftor/ivacaftor (ETI) or vanzacaftor/tezacaftor/deutivacaftor (VTD), many in the CF community are asking if chronic inhaled therapies such as HS or DA can be stopped or not started (in young children). Indeed, many people with CF stably on ETI are already stopping or reducing these chronic inhaled mucoactive therapies (CIMT) without an evidence base to guide shared decision-making.

The REACT trial is a platform trial consisting of two parallel prospective, multicenter, randomized, open-label studies: the Hypertonic Saline (HS) Study and the Dornase Alfa (DA) Study. In the Hypertonic Saline (HS) Study, participants will be randomized to twice-daily inhaled HS or as-needed HS (with acute respiratory illnesses, if considered indicated) for one year. In the Dornase Alfa (DA) Study, participants will be randomized to daily inhaled DA or as-needed DA (with acute respiratory illnesses, if considered indicated) for one year.

Study participation will begin with a 6-week run-in period, during which participants who currently use HS, DA, or both will be instructed to stop these therapies; those who do not use chronic inhaled mucoactive therapies (CIMT) will be instructed to remain off these therapies. At the end of the run-in, eligible participants will be enrolled and assigned first to the HS or DA Study and then randomized to study arm. Participants who use only HS or no CIMT at study entry will be assigned to the HS Study. Those who use DA only at study entry will be assigned to the DA Study. Those who use both HS and DA will be randomly assigned to the HS or DA Study. Participants will be instructed to continue their mechanical airway clearance and inhaled antibiotics (if applicable) as prescribed at study entry. Those who were on both HS and DA at study entry will be instructed to only use the inhaled mucoactive agent to which they have been assigned (HS or DA). Participants randomized to the as-needed arm will be allowed to use the study inhaled agent (HS or DA) temporarily, if considered indicated, with acute respiratory illnesses. Participants in either arm will be allowed to (re)introduce chronic daily therapy if felt to be indicated by the treating physician.

• Absolute Change in Percent Predicted Forced Expiratory Volume in 1 Second (ppFEV1) through Week 52, Relative to Week 0, in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]
• Rate of Protocol-Defined Pulmonary Exacerbations (PEx) through Week 52 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]
• Absolute Change in Respiratory Symptoms, as Measured by the Cystic Fibrosis Questionnaire - Revised Respiratory Domain (CFQ-R RD), through Week 52, Relative to Week 0, in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms [Time frame: 52 weeks]
• Absolute Change in Lung Clearance Index (LCI) from Week 0 to Week 6 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 6 weeks]
• Absolute Change in Percent Predicted Forced Expiratory Volume in 1 Second (ppFEV1) from Week 0 to Week 6 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 6 weeks]
• Absolute Change in Respiratory Symptoms, as Measured by the Cystic Fibrosis Questionnaire - Revised Respiratory Domain (CFQ-R RD), from Week 0 to Week 6 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 6 weeks]
• Absolute Change in Treatment Burden, as Measured by the Cystic Fibrosis Questionnaire - Revised Treatment Burden Domain, through Week 52, Relative to Week 0, in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]
• Absolute Change in Family Impact, as Measured by the Pediatric Quality of Life Inventory (PedsQL) Family Impact Module, through Week 52, Relative to Week 0, in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]
• Healthcare Resource Utilization (HCRU) through Week 52 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]
• Incremental cost-effectiveness ratios (ICERs) through Week 52 in Hypertonic Saline (HS Study) and Dornase Alfa (DA Study) Therapy Arms. [Time frame: 52 weeks]