Ivacaftor benzenesulfonate, used for cystic fibrosis treatment, is an orally bioavailable CFTR potentiator.

Ivacaftor, at a concentration of 10 μM, significantly enhances CFTR activity in cells expressing the W1282X mutation, showing superior efficacy compared to cells with the R1162X mutation. It exhibits negligible activity towards 160 other targets, including the GABAA benzodiazepine receptor. Additionally, ivacaftor notably enhances chloride secretion, demonstrating a 10-fold increase in potency with an EC50 of 0.236 ± 0.200 μM compared to F508del HBEs. In recombinant cells, VX-770 (ivacaftor) markedly improves the CFTR channel's open probability (Po) in the presence of both F508del processing and G551D gating mutations, and amplifies forskolin-stimulated IT in temperature-corrected F508del-FRT cells approximately 6-fold at an EC50 of 25 nM. Ivacaftor triples PC secretion activity for the ABCB4-G535D mutation and significantly amplifies it for ABCB4-G536R (13.7-fold), ABCB4-S1076C (6.7-fold), ABCB4-S1176L (9.4-fold), and ABCB4-G1178S (5.7-fold), effectively correcting the functional defects of these ABCB4 mutations.

Ivacaftor (1-200 mg/kg, p.o.) demonstrates high oral bioavailability in rats.