The much anticipated Phase III data for the combination of lumacaftor and Kalydeco ivacaftor from Vertex Pharmaceuticals Inc. didn't disappoint. Investors boosted the biotech's market cap by $6.4 billion, or 40%, on data that could substantially increase Vertex's penetration of the CF market. The improvements in FEV1 were relatively small but could add up over time and yield long-term benefit for patients.

Last week, Vertex said that in two identical Phase III studies, TRAFFIC and TRANSPORT, Kalydeco and lumacaftor met the primary endpoint of statistically significant improvements in percent predicted forced expiratory volume in one second (ppFEV1) at 24 weeks. The trials enrolled patients ages 12 and older who were homozygous for the delta F508 mutation in the CF transmembrane conductance regulator (CFTR) gene.