Despite one segment that finished the second quarter in the red, all market cap groups are still up for the year. In 2Q13, the sector was led by large caps, which closed up 4%, marking four straight quarters in the black.

Vertex Pharmaceuticals Inc. led the large caps. The company's 46% jump during the quarter was driven by positive data from a Phase II trial of VX-661 to treat cystic fibrosis (CF).