Tuesday April 16, 9:03 PM EDT
By Toni Clarke
NEW YORK, April 16 (Reuters) - Schering AG's (SCHG) multiple sclerosis drug Betaseron proved substantially more effective than Biogen Inc.'s (BGEN) market-leading Avonex in a two-year study, the trial's lead investigator said on Tuesday.
Dr. Luca Durelli, who presented his findings at the annual meeting of the American Academy of Neurology in Denver, said patients taking Betaseron were 42 percent more likely to remain relapse free than patients taking Avonex.
Magnetic resonance imaging showed that patients taking Betaseron were about 50 percent less likely to develop new brain lesions - an indicator of the disease's progression - than patients on Avonex.
"I think this is very impressive data," said Jack Burks, Medical Director of Washoe Institute for Neurosciences in Reno, Nevada. "The weakness in the trial is that the people who gave the medications knew what they were giving and patients knew what they were getting. Having said that, the MRI readings were blinded which acts as a check and gives the trial credibility."
While flawed in the view of some experts, the trial is the latest in a growing body of evidence showing that patients treated with higher doses of the infection-fighting protein interferon, at more frequent intervals, respond better than those treated with the lower dose regimen of Avonex, which is delivered once a week.
In January the American Academy of Neurology issued guidelines supporting the view that higher doses administered with greater frequency are more effective than lower doses with lower frequency. This is a potentially powerful marketing tool for Schering and for Serono AG's (SEOZ) rival drug Rebif, which is also delivered at higher doses than Avonex.
"The AAN is an incredibly well respected organization and it's relatively conservative, so for them to come down on the side of the high-dose more frequent interferons is significant," said Burks.
Durelli's findings, currently being reviewed by experts, are due to be published in a leading medical journal at the beginning of May, Durelli said. The news could represent a blow to Biogen, which is already fighting competition from Rebif.
In March U.S. regulators approved Rebif saying Rebif was clinically superior to Avonex based on data from a six-month trial. Data from 12 months, released in full on Tuesday, also showed Rebif to be superior, but the gap between the two drugs narrowed in the second six months.
In a bid to prove the gap could disappear entirely over time, Biogen on Tuesday said it plans to launch a five-year head-to-head study comparing Avonex with Rebif.
At stake is a market that analysts estimate could reach $4 billion by 2004. Avonex alone generates nearly $1 billion in sales a year. Serono, Europe's biggest biotechnology company, has said it aims to take about 25 percent of the U.S. multiple sclerosis market. The company will release U.S. sales data when it releases its earnings next week.
For Biogen the stakes are particularly high, since Avonex is its only marketed product. Data from the Rebif versus Avonex trial will likely give Rebif a boost among newly diagnosed patients, but not persuade physicians to transfer patients from Avonex to Rebif, physicians said earlier this year.
Combined with the Durelli trial, however, the evidence in favor of Betaseron and Rebif may become convincing enough to persuade physicians to switch patients to either Rebif or Betaseron. The Betaseron versus Avonex trial lasted two years.
Biogen dismissed Durelli's trial, saying it was biased from the start in favor of Betaseron.
"There were more men in the Avonex arm of the trial than in Betaseron arm and we know men less likely to benefit from treatment," said Mariska Kooijmans, director of clinical research at Biogen.
Encouraged by evidence suggesting its higher dose treatment may be more effective than Avonex, Schering said it plans to launch a late-stage trial of a new, higher dose version of Betaseron which it hopes will prove even more effective than its current drug.
"Existing studies have confirmed high doses deliver better effects," said Ludger Heeck, vice president of strategic marketing for specialized therapeutics at Schering. "If this is so, the question is does a drug with an even higher dose deliver even better results."
( New York Health Desk, 646-223-6030--))
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