Thursday's After-Hours Movers: Sohu, Western Union, Insys Therapeutics, Affymetrix

Shares of Insys Therapeutics Inc INSY are up 1.41 percent in after-hours, following a pretty much flat day. No particular news seems to have triggered the surge; in fact, it looks like an overall positive sentiment in relation to the stock is driving the rise. The specialty pharma company has managed to widely outperform the market year-to-date, having returned about 68 percent, versus the Nasdaq’s 5.74 percent surge.

Affymetrix, Inc. AFFX continues to tumble after the bell. Following a 1.7 percent fall during the trading day, the stock is down an extra 1.73 percent in after-hours – on low volume, though. Thursday’s decline comes after Zacks downgraded the stock on Wednesday, from a “Strong Buy” rating to a “Hold” rating.

Also on the move late-Thursday is Sohu.com Inc SOHU, which lost 0.31 percent since the bell rang, after gaining 1.46 percent over the day. The Chinese gaming company’s stock is currently trading at $58.55. Once again, no particular events seem to be moving the stock, but volume is considerable for after-hours trading.

The Western Union Company WU, which fell 6.87 percent during the day, following PayPal’s acquisition of competitor Xoom Corp XOOM and the resulting downgrade of Western Union’s stock by Evercore Partners. However, the transaction and payments services company’s stock is recuperating in after-hours trading, having surged 1.25 percent already.

Year-to-date, Western Union has managed to return 6.03 percent, versus the S&P 500’s 0.84 percent surge.