Blood drug test

Investors reacted to the news through driving down Wyeth’s shares $5.01, or 11.1 percent, in after-hours trading.

Company scientists reported fuller data on the drug, bapineuzumab, on Tuesday at the International Conference on Alzheimer’s Disease in Chicago behind announcing mixed results in June.

Scientists and analysts have been scrutinizing the experimental drug for its potential to slow Alzheimer’s disease in place of just treating its symptoms as current drugs do.

Bapineuzumab also works in a novel way, by enlisting the immune system to clear out the sticky beta-amyloid clumps that clog the brain and kill nerve cells. It is given intravenously every three months, and the study was testing three doses versus dummy infusions.

The drug’s developers — New Jersey-based Wyeth and the Irish company Elan Corp. PLC — previously said that the 240-patient study missed its main conduit goal of improving patients’ mental performance at 18 months.

But the companies rest a silver lining — the drug appeared to help the roughly 60 percent of people in the study who did not have a gene that can make Alzheimer’s ailment more severe.

In those study participants, bapineuzumab raised scores by five points without interruption a widely used 70-point scale of ideal function, said Wyeth scientist Dr. Ron Black.

Two other measures of mental performance furthermore improved in these patients, and MRI images showed real changes as well. There was not any signifying benefit to participants with the apoE-4 gene; roughly half of all Alzheimer’s patients have it.

“Those are good verse. It looks approve it’s in operation,” Dr. R. Scott Turner, incoming director of the memory disorders program at Georgetown University Medical Center, said of the results.

However, 12 cases of a type of brain swelling, vasogenic edema, occurred in those in continuance bapineuzumab and none in the placebo group. It caused few if any symptoms, company scientists said, but Turner said it may have contributed to other side effects that occurred.

These were two or more times more usual in those on bapineuzumab than those given the dummy drug: anxiety, 11 versus 4 percent; paranoia, 7 versus 1 percent; vomiting, 10 versus 4 percent; high blood pressure, 8 versus 4 percent; weight loss, 7 versus 2 percent; and back pain, 12 versus 6 percent.

Three deaths occurred among the 124 patients given bapineuzumab, but they were not related to the put drugs into, said Dr. Sid Gilman of the University of Michigan, who headed the study’session data preservation monitoring board.

One demise was due to pneumonia and brace others to worsening Alzheimer’s disease. Still, the deaths from worsening sickness “sounds ominous,” because none occurred in the placebo group, Turner said.

The results justify going forward by testing the drug, said Dr. Sam Gandy of Mount Sinai School of Medicine in New York, head of the Alzheimer’sitting Association’session according to principles advisory array.

The companies have before that time said they will proceed with late-stage testing in more than 4,000 patients.

The fact the drug did not meet its main goal is “worrying,” before-mentioned Marcelle Morrison-Bogorad, director of Alzheimer’s research at the National Institute on Aging.

“But I think we need to give it a chance,” she said.

Neil Buckholz, a neuroscientist at the federal agency, called the results “very exciting.”

Side effects are always a concern, but “it depends if they are manageable or not, and it appears that they were,” he said.