Cult stocks do well in frothy bull markets, which helps explain MannKind's inclusion on this list. The next round of pivotal clinical trials for the fast-acting inhaled insulin Afrezza are due in August, following two FDA rejections already. With MannKind shares clearly running up in anticipation of the data and the worshipping of company founder Al Mann reaching a zenith, anything less than a stellar performance from Afrezza could hit the stock hard. http://www.thestreet.mobi/story/11946348/1/five-best-performing-biotech-stocks-of-2013-some-may-surprise-you.html?puc=yahoo&cm_ven=YAHOO