tezacaftor

Tezacaftor is a small-molecule medication that acts as a cystic fibrosis transmembrane conductance regulator (CFTR) corrector. In cystic fibrosis (CF), certain CFTR gene mutations produce misfolded CFTR protein that is degraded before reaching the cell surface. Tezacaftor binds to CFTR during biosynthesis and improves folding and trafficking, increasing the amount of functional CFTR at the cell surface.

Tezacaftor is used in combination regimens to treat CF. It is co-formulated with ivacaftor, a CFTR potentiator, as tezacaftor/ivacaftor under the brand name Symdeko. This combination is indicated for patients aged 12 years and older with CF who have either two copies of the F508del mutation or one F508del plus a responsive mutation. Tezacaftor is also a component of a triple therapy, elexacaftor/tezacaftor/ivacaftor (brand Trikafta), which is indicated for a broader CF population, including patients with at least one F508del mutation.

Administration and pharmacokinetics: Tezacaftor and its combinations are taken by mouth, typically with a fat-containing meal to aid absorption. They are primarily metabolized in the liver by CYP3A enzymes; concomitant use with strong CYP3A inhibitors or inducers can affect exposure and may require dose adjustments or avoidance.

Safety: Common adverse effects include headache, nausea, dizziness, nasopharyngitis, and abdominal pain. Elevations in liver enzymes and rash have been reported; patients are monitored for hepatic safety and drug interactions.