Wyeth's Schizophrenia Pill Is Rejected by FDA

(August 10, 2007) -- Wyeth's new schizophrenia drug was rejected by U.S. regulators because it wasn't shown to be effective.

The Food and Drug Administration needs more data showing that the medicine, bifeprunox, works before the agency will consider approval, the Madison, New Jersey-based company said today in a statement. The FDA also requested information on a patient who died while taking the drug.

The product may generate as much as $1 billion in annual revenue if cleared to enter the $16 billion-a-year market for antipsychotics, according to Wyeth. Bifeprunox doesn't cause weight gain, a safety concern with other schizophrenia remedies. Studies have shown the drug's side effects include nausea, and it is less effective than similar medicines such as Eli Lilly & Co.'s Zyprexa and Johnson & Johnson's Risperdal.

"Bifeprunox didn't work as well as Risperdal and Zyprexa in studies, and I can't see much reason to use this drug once generics of the others are available,'' Michael Krensavage, an analyst with Raymond James in New York , said in a telephone interview. Cheaper copies of Risperdal will be available next year, followed by generic Zyprexa in 2011.

Development of Bifeprunox To Continue

Wyeth will continue to develop bifeprunox for patients with chronic schizophrenia who need medicines to prevent future psychotic episodes, said Joseph Mahady, president of Wyeth Pharmaceuticals, in a conference call with investors.

"The FDA has ruled the real potential for the product approval to be in maintenance,'' and not for patients experiencing acute symptoms, Mahady said. Regulators didn't raise safety issues, he said.

Additional tests could take one to two years or longer, depending on whether regulators will review data from ongoing trials or require the company to begin a new study, Wyeth said.

One patient died of multiple organ failure during a bifeprunox trial. That person had fevers, urine in the blood and changes in liver and kidney function before falling into a coma and dying, Wyeth said. The FDA is investigating whether the death was related to bifeprunox or another cause.

Outlook for Bifeprunox

Jon LeCroy, of Natixis Bleichroeder, said even if the drug won approval for maintenance of schizophrenia, as opposed to acute treatment of the mental illness, such a market appeared limited.

"You're really looking at a case where you'd have to switch from an existing agent on someone who is already under control to this product, and physicians typically won't switch drugs when they're working," LeCroy said. "So I don't know who this would be appropriate for."

Schizophrenia

More than 1 percent of the world's population has schizophrenia, including more than 2 million Americans. Bifeprunox, Risperdal and Zyprexa are in a family of medicines known as atypical antipsychotics. These drugs, introduced in the last decade, are designed to cause fewer of the neurological side effects that made users of earlier medications, such as Haldol, tremble, doze off and jerk involuntarily.

Michael Poole, vice president of neuroscience research at Wyeth Pharmaceuticals, said earlier that bifeprunox "didn't perform as well on primary efficacy measures'' as Risperdal and Zyprexa in tests comparing each drug separately to a placebo.

Bifeprunox was more effective at controlling schizophrenia symptoms such as hallucinations and delusions than a placebo in two of three studies, Poole said during a presentation to investors in October.

The dose of bifeprunox needed to be increased gradually over at least a week to reduce nausea, "a difficult practical problem when you're treating acutely psychotic patients,'' Poole said during the presentation. "Patients usually need to have their symptoms brought under control as rapidly as possible to prevent them from being a harm to themselves and others.''

advertisement

Patients using Wyeth's bifeprunox in one study lost an average of 5.1 pounds over six weeks compared with a gain of 5.3 pounds on Zyprexa. Another report found bifeprunox users lost 2.2 pounds compared with a 2.6-pound gain for Risperdal. The data were presented in March at the International Congress on Schizophrenia Research in Colorado Springs .

By Lisa Rapaport
Source: Bloomberg.com

Last updated: 08/07

top ~ next ~ news table of contents ~ send page to a friend

We subscribe to the HONcode principles. Verify here.