The IBB (biotech ETF) has been taking a sizeable hit lately. The IBB started a downward trend in July 2015, and actually slowed a slight reversal in July fo 2016. More recently, however, there has been a downward trend once again. One interesting note is that the downward pattern is largely due to 10 large cap biotech stocks. Small- to mid-cap stocks are actually performing better. In this interview, CNBC interviews trading experts about the downward trend in biotech stocks, and what they expect in the future.