Proteostasis have identified multiple compounds that improve the folding and trafficking of F508del.

These compounds have a similar level of activity to VX809, and when added to VX809, approx 40% of normal CFTR function is reached.

Trials are planned to start in 2015.

Pfizer are focussing on identifying compounds that help restore folding of the F508del protein.

Pfizer aim to move one or more potential medications into clinical trials by the end of the multi-year collaboration.

The CFF have also collaborated with Vertex, Genzyme and Proteostasis.