On July 18, Vertex Pharmaceuticals announced dramatic results from triple-drug combinations that could potentially treat almost 90% of people with cystic fibrosis (CF). The three triple-agent combinations are the first investigational regimens to show a lung function benefit in individuals with both F508del mutations and minimal function mutations (F508del/min), a vast improvement in the proportion of CF patients amenable to treatment. Vertex's first CF drug Kalydeco (ivacaftor) is approved to treat mutations in the gene that gives rise to CF, present in 6.7% of the global CF population, including those with certain residual function mutations (Nat. Biotechnol. 35, 606, 2017). Vertex's other approved CF drug, Orkambi (lumacaftor), counters defects caused by two copies of the F508del mutation present in about 50% of the patient population, although clinical improvements with this drug are modest. CF results from genetic alterations in the cystic fibrosis transmembrane conductance (CFTR) gene, which codes for a protein involved in ion transport across epithelial cell membranes. Kalydeco facilitates ion channel function on the cell surface, whereas Vertex's investigational agent tezacaftor improves the defective CFTR protein's positioning on the cell surface. Phase 3 studies with Kalydeco–tezacaftor combinations released in March 2017 were encouraging, but patients with minimal-function mutations, who have little-to-no functioning CFTR protein, failed to respond. In the latest studies, to target this group of patients, the Boston-based biotech added one of three experimental drugs that target minimal-function mutations (VX-445, VX-659 or VX-152) to the Kalydeco–tezacaftor combination. In the phase 2 studies with the triple combinations using VX-152 or VX-440 with Kalydeco–tezacaftor, the data revealed a 9.7% and 12.0% benefit, respectively, in lung function as measured by mean absolute improvements in percent predicted forced expiratory volume in one second (ppFEV1). A phase 1 study of VX-659 in a triple combination showed a 9.6% lung function improvement. The safety and efficacy data are “clear and compelling, indicating significant benefit for people with CF from each of these three different triple combination regimens,” Vertex executive vice president and chief medical officer Jeffrey Chodakewitz said in a press release.Vertex's stock jumped 21% on the news. Geoffrey Porges, biotech analyst with Leerink Research in New York, said that, “Within a year or two we cannot see any reason why 100% of the CF patient population who carry a F508del allele (roughly 87% of the total prevalent pool of patients) will not be on one of these medicines.”