Biotech stocks outperformed the broader markets Wednesday with a few stocks moving on data.

The Nasdaq and Amex biotechnology indices were up 1.2% and 0.7%, respectively. The Amex Pharmaceutical index lagged and was flat on the day.

Sequenom ( SQNM) shares soared 35% to $27.76 after the company shared new data late Tuesday indicating that its prenatal test should be able to detect Down syndrome at week 10 or earlier. The company also said in the new first- and second-trimester samples, the test continued to demonstrate no false positives or negatives. Sequenom plans to launch the test in the first half of 2009.

On the weak side, Medicis ( MRX) shares were down 13% after the company announced that it will have to restate its earnings for 2003 through the second quarter of 2008. The company said the adjustment is due to a change in its interpretation of GAAP principles relating to its reserve calculations.

Also, abstracts were released for the American Association for the Study of Liver Disease, sending hepatitis C drug company Vertex ( VRTX - Get Report) up 16% to $31.66.

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Discovery Labs ( DSCO) was lower by 6.1% after saying it's completing the information for its complete response to an FDA letter on Surfaxin, its prospective drug for the prevention of respiratory distress syndrome in premature infants. The company said it expects to submit its response in the next four weeks and believes that it could be reviewed and approved by the agency before the end of the year.

Among analyst actions, Needham cut its rating for Natus ( BABY), which makes newborn-care products, to hold from buy, predicting a decline in hospital spending. The stock was off more than 8%.

JMP Securities initiated coverage on Anadys Pharma ( ANDS) with a market perform rating and a $6 price target, sending the shares up 7.9%.

Also, Robert W. Baird began tracking Regeneron ( REGN - Get Report) with a neutral rating and a $25 price target. Shares were down 0.6%.