More than 1,900 mutations have been identified in the CF gene. Although the biological effects of many CFTR mutations are known, there continue to be mutations for which we have incomplete knowledge of their health effects. The most common CFTR mutation is a deletion of just three DNA nucleotides, which leads to the deletion of an amino acid (phenylalanine) at position 508 of the protein sequence. This is denoted as ΔF508, and is found in around 85% of CF patients.
In 2012, the FDA approved Kalydeco (Ivacaftor) from Vertex Pharmaceuticals (VRTX), for patients having the specific G551D mutation (a Class III mutation) in their CFTR gene. Kalydeco is the first drug which treats the underlying cause of the illness instead of the symptoms. Unfortunately, patients with that mutation (G551D) only represent 3% of all CF patients. There is a need to find novel molecules that will have an effect on other CFTR mutations and especially one called ΔF508a. Therefore, we have identified and are developing a more active corrector that acts in synergy with Vertex' VX-809 on ΔF508CFTR.