Genentech Inc. (DNA) and Roche Holding AG (ROG.VX) said a study examining the potential benefits of combining cancer drugs Tarceva and Avastin was stopped early because it became clear that people with lung cancer who received the treatment lived longer without their cancer getting worse, compared to those who received Avastin alone.

Genentech, based in South San Francisco, CA, and Roche, based in Basel, said this was the second late-stage study that demonstrated the benefits of daily pill Tarceva as an initial maintenance therapy, following inital treatment with Avastin. Genentech sells both drugs in the U.S., while Roche has the right to sell them in other markets. Avastin is one of the companies' fastest-growing products.

Shares of Genentech and OSI Pharmaceuticals Inc . (OSIP), which are selling Tarceva in the U.S. rose in after-hours trading Monday after Genentech gave details of the findings. Roche shares closed at CHF163.50 on Monday.

The Swiss drugmaker plans to take full control of Genentech, which developed many of the successful cancer drugs that are driving Roche's growth.

Last Friday, Roche launched a hostile bid to buy the roughly 44% of the U.S. biotech company that it doesn't already own, after its earlier friendly offer was rejected.

Company Web Site: http://www.roche.com

-By Anita Greil, Dow Jones Newswires; +41-43-4438044; anita.greil@dowjones.com

Click here to go to Dow Jones NewsPlus, a web front page of today's most important business and market news, analysis and commentary. You can use this link on the day this article is published and the following day.