March 31 (Bloomberg) -- Takeda Pharmaceutical Co. and Abbott Laboratories won a ruling that will prevent Teva Pharmaceutical Industries Ltd. from selling a generic version of the heartburn drug Prevacid until May 2009.

U.S. District Judge Sue L. Robinson in Wilmington, Delaware, today said a patent on the drug is both valid and enforceable. Teva, which had conceded it infringed the patent, pledged to appeal.

The drug is made by TAP Pharmaceutical Products Inc., a venture between Takeda and Abbott. The companies earlier this month agreed to split the venture, with Takeda getting Prevacid. Analysts said today's decision will ensure that agreement goes as planned since a loss would have required a renegotiation between Abbott and Takeda.

The ruling ``will ease investor concerns regarding the pending split of the TAP joint venture between Abbott and Takeda,'' analyst Lawrence Keusch of Goldman Sachs said in a note to clients. ``The ruling should also keep generic competition at bay and allow Abbott to collect royalties on an intact Prevacid franchise prior to the patent expiration in 2009.''

Robinson upheld the validity of two patents on the medicine. She said Teva didn't infringe one, which expires in September. The patent that is infringed covers the compound lansoprazole, the key ingredient in Prevacid.

``We're obviously ecstatic, it's something we've been looking forward to and we're happy they upheld the validity and enforceability of the patents,'' said TAP spokeswoman Amy Martin.

Takeda, based in Osaka City, Japan, fell 110 yen to 4,990 in trading in Tokyo today. American depositary receipts of Petah Tikva, Israel-based Teva, each representing one ordinary share, rose 18 cents to $46.19 at 5:20 p.m. New York time in Nasdaq Stock Market composite trading.

Abbott Park, Illinois-based Abbott rose $2.08, or 3.9 percent, to $55.15 in New York Stock Exchange composite trading.

The case is Takeda v. Teva Pharmaceuticals USA, 06CV33, U.S. District Court, Delaware (Wilmington).

To contact the reporter on this story: Susan Decker in Washington at sdecker1@bloomberg.net; Phil Milford in Wilmington, Delaware, at pmilford@bloomberg.net.

Last Updated: March 31, 2008 18:09 EDT