Shares of the rare disease drugmaker are already up more than 40% over the past year.Except for the last several days, the past 12 months have been pretty good for stocks across the board and especially successful for Vertex Pharmaceuticals (VRTX -3.55%). Shares of the biotech stock surged by 42% during the 12 months ended Aug 5.Now that it's already risen a great deal, investors are wondering if they've missed the boat on this stock.Can Vertex Pharmaceuticals stock keep rising in the years ahead or is it t ...