Tezacaftor is a drug used in the treatment of cystic fibrosis. It is a cystic fibrosis transmembrane conductance regulator (CFTR) modulator that helps improve the function of the CFTR protein in people with certain mutations of the gene responsible for cystic fibrosis. Tezacaftor is often used in combination with ivacaftor, another CFTR modulator, to treat patients with cystic fibrosis. Research in this area focuses on the efficacy and safety of tezacaftor in improving lung function and quality of life for individuals with cystic fibrosis.