Top Percentage Gainers and Losers as of 10am 4/15/11 (AGO, OPXA, MBI, AMLN, ABMD, CTCT, CRUS, GGC, OTIV, SFG, BAC, LLY, ALKS) - Assured Guaranty (NYSE:AGO)

Best

1) Opexa Therapeutics

OPXA

: Trading up 24% from yesterday's close to $2.27. A positive report emanating from a clinical trial of its drug Tovaxin has shares up. 2) Assured Guaranty

AGO

: Trading up 18.84% from yesterday's close to $16.84. Bank of America

BAC

has agreed to pay Assured $1.1 billion to buy back defective mortgages. 3) MBIA

MBI

: Trading up 12% from yesterday's close to $10.00. Soleil Securities reiterated its Buy rating on shares of the company. 4) Amylin Pharmaceuticals

AMLN

: Trading up 10.12% from yesterday's close to $12.40. A positive recommendation from European Union regulators regarding a diabetes drug developed by Amylin, Eli Lilly & Co

LLY

, and Alkermes

ALKS

has the stock up. 5) ABIOMED

ABMD

: Trading up 8.15% from yesterday's close to $16.32.

Worst

1) Constant Contact CTCT: Trading down 9.45% from yesterday's close to $31.08. The company was downgraded from Buy to Hold at Needham.

2) Cirrus Logic CRUS: Trading down 8.3% from yesterday's close to $16.59. Shares are sliding after the company lowered its margin outlook and reported manufacturing problems with one of its projects.

3) Georgia Gulf GGC: Trading down 7.8% from yesterday's close to $34.70.

4) On Track Innovations OTIV: Trading down 6.7% from yesterday's close to $2.51.

5) StancCorp Financial SFG: Trading down 5.8% from yesterday's close to $42.74.

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