Study design (if review, criteria of inclusion for studies)
Interventional - Allocation: Randomized|Intervention Model: Parallel Assignment|Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)|Primary Purpose: Treatment
Participants
Cystic Fibrosis - 18 Years and older (Adult, Older Adult)
Interventions
Drug: VX-561|Drug: IVA|Drug: Placebo
Outcome measures
Absolute change in percent predicted forced expiratory volume in 1 second (ppFEV1)|Absolute change in sweat chloride concentrations|Maximum observed concentration (Cmax) of VX-561, IVA, and relevant metabolites|Area under the concentration versus time curve during a dosing interval (AUCtau) of VX-561, IVA, and relevant metabolites|Observed pre-dose concentration (Ctrough) of VX-561, IVA, and relevant metabolites|Safety and tolerability as assessed by number of subjects with adverse events (AEs) and serious adverse events (SAEs)