Cystic fibrosis (CF) is a genetic disease caused by any one of the more than 2,000 mutations identified in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. CFTR mutations lead to aberrant chloride transport in a variety of tissues, most notably the lungs and pancreas; as a result, CF patients generally suffer from pancreatic damage, which affects their metabolism and nutrient absorption. Chronic respiratory problems, such as persistent lung infection stemming from the accumulation of thick, viscous mucus in the lungs, can result in respiratory failure and is the leading cause of death in CF.
Historically, therapeutic options for CF were limited to symptomatic therapies. Recently, disease-modifying therapies (DMTs) have become a reality for a subset of CF patients with the market entry of Vertex’s franchise, including Kalydeco (ivacaftor), a small-molecule CFTR potentiator; Orkambi, a combination of Kalydeco and the CFTR corrector lumacaftor; and Symdeko, a combination of Kalydeco and a next-generation CFTR corrector (tezacaftor). Pipeline agents from Vertex and other companies (e.g., Galapagos/AbbVie) are poised to compete in this lucrative market by seeking to improve upon the performance of marketed DMTs or expand DMTs’ reach in the CF population.