Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX) is today’s top market gainer midday, followed by William Lyon Homes (NYSE:WLH) and Novacopper Inc (NYSEMKT:NCQ). The biggest losers this Tuesday are Senomyx Inc. (NASDAQ:SNMX), AuRico Gold Inc (NYSE:AUQ) and Chicago Bridge & Iron Company N.V. (NYSE:CBI).

Vertex Pharmaceuticals

Vertex Pharmaceuticals Surges

Vertex Pharmaceuticals Incorporated (NASDAQ:VRTX) soared +40.87% today, rendering it this Tuesday’s top midday gainer. The small molecule drug developer said this morning that a combination of two of its drugs has successfully treated cystic fibrosis in clinical trials – a major piece of news. Billionaire investor George Soros isn’t likely regretting his decision to pick up 10,000 shares of the biotech company during the first quarter of the year.

William Lyon Homes (NYSE:WLH) jumped +6.04% following yesterday’s announcement that it will purchase the residential home-building operations of Polygon Northwest Co. LLC. In John Paulson’s portfolio across four consecutive quarters, WLH is up +24.42 YTD.

Novacopper Inc (NYSEMKT:NCQ) climbed +6.01% midday. Its share price has increased a total +15.22% over the past five days. Billionaire Seth Klarman has held a position in the base metals exploration company across several quarters, as has John Paulson.

Senomyx Sales Lead to Losses

Senomyx Inc. (NASDAQ:SNMX) dipped -5.61%. Last week, company SVP Sharon Wicker unloaded 50,100 SNMX shares, the same day the firm’s VP, Donald Karanewsky, sold off 20,000 of his. While these sales may have some investors wary, the company is still up +70.16% YTD.

AuRico Gold Inc (NYSE:AUQ) slipped -4.98% midday. Like Senomyx, AuRico is a new Q1 acquisition for George Soros. The gold producer’s stock price is up a modest +15.03% in 2014.

Down -4.42, Chicago Bridge & Iron Company N.V. (NYSE:CBI) rounds out today’s list of middle-of-the-day losers. The company entered into oversold territory last week, and this week, new options began trading for an August 16th expiration. CBI has had a rough go in 2014, its price falling -21.39% since the start of the year. David Tepper and Warren Buffett, however, continue to bet on the infrastructure firm.