This is a Phase 3, parallel group, multicenter, rollover study in participants with CF who are homozygous or heterozygous for the F508del CFTR mutation and who previously participated in Study 103 (Study VX12-809-103, NCT01807923), Study 104 (Study VX12-809-104, NCT01807949), or Cohort 4 of Study 102 (Study VX09-809-102, NCT01225211).