Splice mutations are abnormalities in the CFTR DNA code that result in either lower amounts of protein or a slightly altered (and therefore ineffective) CFTR protein. As a result, there is a significant reduction in the amount of CFTR protein that reaches the cell surface. In the U.S. there are more than 600 people ages 2 and older with one of these five mutations in the CFTR gene who are now eligible for treatment with ivacaftor (Kalydeco®).
Ivacaftor is a type of CFTR modulator called a potentiator that increases activity of the CFTR protein at the cell surface and has been shown in studies to improve lung function. The drug was developed by Vertex Pharmaceuticals Inc. with significant clinical, scientific, and financial support from the Cystic Fibrosis Foundation.
For additional information regarding today's news, please see the announcements from Vertex.
About Cystic Fibrosis Mutations
People with CF have two mutated copies of the CFTR gene -- one inherited from each parent. There are more than 1,700 mutations in the CFTR gene that cause CF.
With today's announcement by the FDA, ivacaftor is approved to treat the following mutations:
| E56K | G178R | S549R | K1060T | G1244E | 3272-26A->G |
| P67L | E193K | G551D | A1067T | S1251N | 711+3A->G |
| R74W | L206W | G551S | G1069R | S1255P | E831X |
| D110E | R347H | D579G | R1070Q | D1270N | |
| D110H | R352Q | S945L | R1070W | G1349D | |
| R117C | A455E | S977F | F1074L | 3849+10kbC->T | |
| R117H | S549N | F1052V | D1152H | 2789+5G->A |