The S&P 500 soared more than 32% in 2013, and several big pharma companies, namely Bristol-Myers Squibb (NYSE:BMY), AbbVie (NYSE:ABBV), Roche (NASDAQOTH:RHHBY), Johnson & Johnson (NYSE:JNJ), and AstraZeneca (NYSE:AZN) also performed extraordinarily well. The following slideshow reveals why these companies beat out their big pharma peers and what drove their strong performances in 2013.