NEW YORK ( TheStreet) -- Shares of Ironwood Pharmaceuticals ( IRWD) took off in extended trades late Monday after the company and partner Forest Laboratories ( FRX) reported positive top-line results for a clinical trial of a drug to treat patients suffering from irritable bowel syndrome with constipation.

Ironwood shares leapt 23% to $12 on volume of more than 72,000, according to Nasdaq.com following the news. The Cambridge, Mass.-based company completed its initial public offering in early February with the stock pricing at $11.25 per share.

In a statement, Ironwood and Forest said the positive top-line results relate to the safety and effectiveness of their investigational drug linaclotide in the first of two phase III clinical trials.

The companies said a second phase III trial of the drug for similar patients is ongoing with top-line results expected sometime in the fourth quarter.

In other news after the closing bell, video game maker THQ Inc. ( THQI) lowered its financial outlook after moving back the release date of its Red Faction Armageddon title to May 2011. It said in June that it would release the game in March 2011.

THQ now sees revenue of between $800 million and $825 million for its fiscal 2011 ending in March 2011 with a non-GAAP loss of 10 to 20 cents a share. Its previous view was for breakeven results on the year on sales ranging from $845 million to $865 million.

The stock closed Monday at $3.73, up 7%, with volume of 1.6 million vs. its usual churn of around 1 million. So far in 2010, however, the shares have fallen 31% through Monday's close.

On August 9, the company reported its first-quarter results, coming in with a non-GAAP loss of $14.4 million, or 21 cents a share, that was narrower than Wall Street expectations for a loss of 24 cents a share. The stock sold off in the wake of the report, however, tumbling from around $4.50 just prior to a scrape a 52-week low of $3.33 on August 13.

Also, GTSI Corp. ( GTSI) should be in focus again on Tuesday after the Herndon, Va.-based provider of technology products and services to government agencies said its board has rejected an unsolicited buyout proposal from Eyak Technology LLC.

GTSI shares surged 33% to $6.89 during Monday's session on news of the hostile bid from Eyak, which values GTSI shares at $7 each.

If you liked this article you might like

Ironwood Shares Jump on FDA Approval for Hyperuricemia Drug - Biotech Movers

5 Ways Allergan Can Keep Up Momentum

Premarket Biotech Movers: Ironwood Pharmaceuticals, Rigel Pharmaceuticals, FibroGen

Synergy Pharmaceuticals Secures Approval for Linzess Competitor

Ironwood Pharmaceuticals (IRWD): Today's Weak On High Volume Stock