The sell-off in high-growth companies -- especially in tech and biotech names -- continued to snowball on Friday. What began last month with a single letter from three congressmen questioning the pricing of Gilead Sciences' Sovaldi has turned into a legitimate sell-off. Biogen Idec (NASDAQ:BIIB), Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX), and Broadcom Corp. (UNKNOWN:BRCM.DL) each ended in the dredges of the stock market today. The S&P 500 Index (SNPINDEX:^GSPC) lost 17 points, or 1%, to end at 1,815. 

Biogen Idec, a biotechnology company that offers treatments for ailments from hemophilia to MS, lost 4.7% today. The stock ended as the worst performer in the entire S&P 500 Index, as indiscriminate selling among peers in the industry hit shares where it hurts. The biotechnology industry was down an astounding 7.7% in all today, so many of Biogen's smaller peers posted even steeper losses on Friday. Investors will get a better glimpse on April 23 of whether the recent slump in share prices was warranted or not, when Biogen reports its quarterly earnings.

Source: Vertex Pharmaceuticals website

Shares of Vertex Pharmaceuticals also lagged the market, plunging 4% in trading today. Vertex's business is essentially reliant upon two drugs: Kalydeco, which treats cystic fibrosis, and Incivek, which treats hepatitis C. Kalydeco is seen as the growth engine of the future, as Incivek's sales have wound down from a blistering pace of $450 million a quarter in 2011 to $86 million a quarter and declining in recent periods. Consider the fact that the biotech space is in a freefall right now, and it's no wonder Vertex shares are reeling. 

Lastly, Broadcom Corp. finished as a major underperformer, losing 3.3% in trade. The company is already going through an adjustment period, as the cooling of the smartphone market has kept the share price of the chipmaker in check. With a P/E of 40, the dreaded label of being a technology company in a sector-specific sell-off, and recent downgrades by research outfits, Broadcom doesn't seem to have much going for it. Personally, while I do think the recent marketwide pullback is a healthy reality check, I don't think Wall Street's giving Broadcom a fair shake, and pessimism surrounding the company provides a good entry point for long-term investors.

John Divine has no position in any stocks mentioned. You can follow him on Twitter @divinebizkid and on Motley Fool CAPS @TMFDivine.

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