Tezacaftor

The transport of charged ions across cell membranes is normally achieved through the actions of the cystic fibrosis transmembrane regulator (CFTR) protein. This protein acts as a channel and allows for the passage of chloride and sodium. This process affects the movement of water in and out of the tissues and impacts the production of mucus that lubricates and protects certain organs and body tissues, including the lungs. In the F508del mutation of the CFTR gene, one amino acid is deleted at the position 508, therefore, the CFTR channel function is compromised, resulting in thickened mucus secretions.

Tezacaftor is a CFTR corrector that aims to repair F508del cellular misprocessing. This is done by modulating the position of the CFTR protein on the cell surface to the correct position, allowing for adequate ion channel formation and increased in water and salt movement through the cell membrane. The concomitant use of ivacaftor is intended to maintain an open channel, increasing the transport of chloride, reducing thick mucus production.