Teva Pharmaceutical Industries rose more than 11% on Sunday after a U.S. court upheld Teva's patents for multiple sclerosis drug Copaxone well into 2015.

Israel-based Teva, the world's largest generic drugmaker, had filed a suit against Momenta Pharmaceuticals and Sandoz as well as Mylan Laboratories and Natco Pharmaceuticals for infringement of multiple patents for Copaxone, a branded drug that is expected to generate $3.8 billion of Teva's total revenue of $20-$21 billion in 2012.

A U.S. District Court judge on Friday rejected challenges to the Copaxone patents. Teva, which itself has battled the world's top drugmakers' patents, believes a generic version of Copaxone will not be allowed to be sold until after the last patent expires on Sept. 1, 2015.

The verdict was subject to appeal.

"The combination of winning the trial and being able to defend its longest patent was the best outcome for Teva," said Sabina Podval, an analyst at Leader Capital Markets. "This will support the stock and give Teva's management more time to prepare itself for the day Copaxone will go generic."

Podval raised her rating for Teva's shares to "buy" from "outperform" but maintained a $49 target for the company's New York Stock Exchange-listed shares.

Teva's shares had been close to 5% down since the beginning of the year after losing 17.5% in 2011. Investors had been worried about generic competition to Copaxone and how Teva would replace a drug that comprises some 20% of its sales.

Biogen is preparing to launch its experimental MS drug BG-12 in 2013.

Teva's shares suffered further when it cut its profit and revenue view for 2012 after new CEO Jeremy Levin, a former Bristol-Myers Squibb executive, took over last month. The reduced outlook largely stemmed from weakness in Europe.

Podval estimated that Teva will gain an additional $2.5 billion in profit from being able to keep its Copaxone patent through much of 2015. She noted that Teva had been expected to protect its Copaxone patent until May 2014 but it was a surprise when the judge upheld the patent for another 15 months.

Earlier this month, Teva said a Phase III clinical trial met a primary endpoint of reducing the annualised relapse rate by 34.4% compared to placebo in a 40 mg Copaxone dose administered three times a week. Copaxone is currently a 20 mg dose given daily.

"This (patent) win, along with the recently released positive data from the ... study suggests that the new formulation of Copaxone - requiring less frequent dosing - could be approved by mid year 2013 and Teva now has over two years to switch patients to this, making the franchise much more sustainable longer term," RBC Capital Markets analyst Shibani Malhotra, wrote in a note to clients.

"We currently expect at least 30% of the franchise will move to the new form of Copaxone," said Malhotra.