Ivacaftor potentiation of multiple CFTR channels with gating mutations.

Background: The investigational CFTR potentiator ivacaftor (VX-770) increased CFTR channel activity and improved lung function in subjects with CF who have the G551D CFTR gating mutation. The aim of this in vitro study was to determine whether ivacaftor potentiates mutant CFTR with gating defects caused by other CFTR gating mutations.

Methods: The effects of ivacaftor on CFTR channel open probability and chloride transport were tested in electrophysiological studies using Fischer rat thyroid (FRT) cells expressing different CFTR gating mutations.