Vertex gains nearly $4B in market cap on positive cystic fibrosis data

Shares of Vertex Pharmaceuticals surged Tuesday evening after the Boston drugmaker reported positive results from two closely watched trials of a combination treatment for cystic fibrosis, moving the company closer to its goal of treating nearly all patients with the lung disease. Vertex (Nasdaq: VRTX) said that a combination of its blockbuster drug Kalydeco and another cystic fibrosis treatment called tezacaftor had helped patients in both Phase 3 trials improve lung function. Shares of Vertex…