A high dose of Teva Pharmaceutical Industries Ltd.‘s multiple sclerosis drug Copaxone is more effective at limiting relapses and brain lesions than the standard dose, without more side effects, researchers said on Wednesday.

“For some people a higher dose may work better,” said Dr. Jeffrey Cohen of the Cleveland Clinic’s MS research center and lead investigator of a small nine-month trial comparing the two doses.

The study, funded by Israel-based Teva, found that a 40-milligram injection of Copaxone reduced inflammatory disease activity 38 percent more than a 20 mg dose.

Rates of side effects, mainly injection site reactions, were unchanged, Cohen said.

Sales of Copaxone, co-marketed by Sanofi-Aventis, grew 26 percent globally in 2005. Teva Vice President Rivka Kreitman attributed the trend to increased awareness of the drug’s effectiveness.

Copaxone is approved to treat relapsing-remitting multiple sclerosis, the most common form of the disease, which causes a progressive disability that can include blurred vision, weakness, poor muscle coordination and loss of memory and mental function as nerves lose their insulating sheath.

The study of 90 patients not previously treated with the drug also showed that the double dose reduced relapse rates by 77 percent compared to rates before the trial, while the lower dose cut relapses by 62 percent.

The time to the first relapse was stretched to 213 days from 80 days, Teva said.

The company said it plans to launch in the second half of this year a large-scale Phase III study designed to confirm the findings, which were presented at a San Diego meeting of the American Academy of Neurology.

Those results are expected in 2008, Kreitman said.

The Teva drug competes with MS treatments from Switzerland’s Serono SA, the U.S.‘s Biogen Idec and Germany’s Schering AG.

Current MS drugs are only partially effective, suppressing disease symptoms by about 30 percent, Cohen said.

“Patients continue to have disease activity despite being on medication ... we are very encouraged by these results suggesting that a higher dose of Copaxone may be more effective,” he said.

The drug’s sales totaled $1.18 billion in 2005, of which $782 million were in the United States, where Copaxone increased its market share to more than 34 percent of new prescriptions, Teva has said.

The drug sells for about $20,000 a year in the United States, according to Kreitman.

Copaxone’s use is up amid wariness over risks of interferons, like Serono’s Rebif and Biogen’s Avonex, which can include development of neutralizing antibodies that render the drugs ineffective, Cohen said.

Teva and partner Lunbeck A/S in March halted development of an oral version of Copaxone, saying the formulation never lived up to expectations.

Kreitman said Teva expects to announce toward the end of this year results from a mid-stage trial of its experimental oral MS drug called Laquinimod.