This is a multicenter, multi-country, Phase 2, three parallel-cohort study of galicaftor, navocaftor, and ABBV-119 or ABBV-576 combination therapy for 28 days in adult CF subjects who are homozygous or heterozygous for the F508del mutation, including subjects already on stable CFTR modulator therapy. This study is designed as a proof-of-concept study to evaluate the safety, tolerability, target engagement, and efficacy for galicaftor/navocaftor/ABBV-119 and galicaftor/navocaftor/ABBV-576 combination therapies administered at fixed doses. Cohort 3, the only cohort that our site is participating in for this study, is for those homozygous for F508del mutation, where this mutation is present on both copies of the CFTR gene; or heterozygous for the F508del mutation, where the F508del mutation is only present in one copy of the CFTR gene, and the other copy of the CFTR gene carries another mutation that is different from F508del. Cohort 3 is open label, meaning there is no placebo and both the patient and the study doctor will know what study treatment and what dose you are receiving. Approximately 40 subjects will be enrolled in Cohort 3, 20 subjects who are homozygous for the F508del mutation and up to 20 subjects who are heterozygous for the F508del mutation.