Biotech's strong run since the beginning of the year has hit some potholes, with last week's 5 percent fall in the BioCentury 100 Price Level index the third downtick in the past four weeks

When the BioCentury 100 peaked on Feb. 14 at 1337.17, it was up an impressive 11.5 percent on the year, compared with a 5.9 percent gain in the NASDAQ Composite, an 8.4 percent gain in the Dow Jones Industrials, and a 9.1 percent gain in the S&P 500. The 190 companies in the Carson Life Sciences Index of smaller cap companies (<$500 million) gained $3.5 billion in aggregate market capitalization (15.6 percent) in the year to Feb. 14, while the Large Cap group had added $700 million (2.3 percent).