Functional evaluation of VX-445-based combinations on F508del/F508del human bronchial epithelial cells. (A) Representative traces of the effect of vehicle alone (DMSO) or VX-445 (3 µM), VX-809 (3 µM), or VX-661 (10 µM) as single agents or combinations in F508del/F508del bronchial epithelial cells (BE91 and BE86) with the short-circuit current technique. (B) Summary of results obtained from short-circuit current recordings on F508del/F508del bronchial epithelial cells derived from four different CF patients. Data reported are the amplitude of the current blocked by 10 µM inh-172 (ITOT; mean ± SD, n = 5). Asterisks indicate the statistical significance of single correctors vs. control (DMSO-treated): *, p < 0.05; ***, p < 0.001. Other symbols indicate the statistical significance of combinations of correctors vs. VX-445 alone: §, p < 0.05; ns, not significant.