FDA backs Kalydeco for eight additional mutations that cause cystic fibrosis

The US Food and Drug Administration (FDA) approved biotech firm Vertex Pharmaceuticals’ (Nasdaq: VRTX) supplemental New Drug Application for Kalydeco (ivacaftor) for people with cystic fibrosis (CF) aged six and older who have one of eight additional mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene.

Kalydeco was first approved in January 2012 for people with CF aged six and older who have at least one copy of the G551D mutation. With the approval of the sNDA, Kalydeco is now approved for use in people with CF with the following nine mutations: G551D, G178R, S549N, S549R, G551S, G1244E, S1251N, S1255P and G1349D. In the USA, about150 people aged six and older have one of the additional eight mutations for which Kalydeco is now approved.

CF is caused by defective or missing CFTR proteins that result from mutations in the CFTR gene. The defective function or absence of CFTR proteins in people with CF results in poor flow of salt and water into and out of the cell in a number of organs, including the lungs. Ivacaftor facilitates increased chloride transport by potentiating the channel-open probability (or gating) of the CFTR protein.