Zyprexa vs. Risperdal Test Results

Eli Lilly & Co.'s new schizophrenia drug Zyprexa came out on top in a rare head-to-head scientific matchup with the market leader, Johnson & Johnson's Risperdal.

A study of the two drugs released Thursday showed Zyprexa worked only slightly better than Risperdal, but was much less likely to trigger the bizarre side effects often caused by anti-psychotic drugs.

The effects, including uncontrolled tremors, facial ticks and muscle rigidity, are a big problem for many of the 1 million to 2 million Americans who suffer from schizophrenia. Often patients are forced to abandon drugs that otherwise helped them lead more normal lives.

Securities analysts said if the research holds up under scientific review over the coming months, Lilly can use it as a sales weapon in a market estimated at $1.5 billion. Even so, the analysts agreed Risperdal could still thrive because the overall market is growing

The study was paid for by Lilly, a common practice in the industry. J&J dismissed the study, saying the research was flawed and the results biased.

J&J introduced Risperdal two years ago. It was the first drug in decades to treat a broad range of symptoms and reduce side effects. Zyprexa was approved by the Food and Drug Administration in October.

Unlike many older drugs, both treat so-called positive symptoms such as delusions, hallucinations and disorganized thinking, and negative symptoms such as apathy, social withdrawal and a sense of isolation.

Drug companies rarely undertake comparison studies with competitors because of the chance they will lose.

Lilly's study was reported in San Juan, Puerto Rico at a meeting of the American College of Neuropsychopharmacology, a prominent organization of doctors who use drugs to treat mental disorders.

The results covered 297 patients who had taken the drugs between eight and 28 weeks.

After 28 weeks, 21.1 percent of patients on Risperdal reported involuntary tremors or movements similar to Parkinson's disease, compared with 11.2 percent on Zyprexa.

In another common side effect, 29.8 percent of Risperdal patients suffered from an inability to sit still, compared with 15.6 percent of those on Zyprexa.

Dr. Bruce Given, vice president of the J&J subsidiary Janssen Pharmaceutica, said the researchers used inordinately high dosages of Risperdal, which would prompt higher side effects.

Given also said Lilly may have plucked results from the study that showed Zyprexa in the best light, leaving other data out.

In addition, the study runs contrary to all previous research, he said.

"I've never seen a situation where one drug won every single measurement. Pure statistical chance says that shouldn't happen."

Lilly spokeswoman Lori Roberts said high dosages of Zyprexa were also used. She said the study was designed according to the treatment protocols specified by the manufacturers and denied it was biased.

Christina Heuer, an analyst at Smith Barney in New York, said the results are a surprisingly big win for Lilly.

"It was like a football game where you not only shut out your opponent, but hold them to a handful of first downs and knock their quarterback out of the ball game."

Analyst Hemant Shah in Warren, N.J. added: "They're going to submit this to the FDA and if it approves, they are going to aggressively use it (in their marketing),"

Heuer added that there is plenty of room for both drugs, as psychiatrists switch their patients from older, problematic drugs such as Sandoz's Clozaril, J&J's Haldol and and SmithKline Beecham's Thorazine.

Others pointed out that Risperdal is usually less expensive than Zyprexa. List prices show a daily dose of Risperdal is roughly $4 to $6 compared with $6 to $8 for Zyprexa. Older drugs cost less than $1 a day.

Dr. Robert Conley, an assistant research professor at the University of Maryland School of Medicine in Baltimore, said some aspects of the study design might favor Lilly, but more detailed review is needed before he could say whether it is valid.

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