Alzheimer's drugs aim to change course of disease

Alzheimer's researchers are cautiously hopeful that three new drugs undergoing clinical trials will slow the course of the mind-robbing disease.

At this week's Alzheimer's Association International Conference in Vancouver, 4,000 experts will hear about three drugs that have taken nearly $1 billion and 20 years to reach the stage 3 clinical trial phase. The research follows more than a decade of failed attempts to stop Alzheimer's in its tracks.

The new drugs all aim to get rid of the amyloid protein suspected of being involved in the death of brain cells. Current medications help with symptoms temporarily.

"It would for the first time give us a medication that changes the course of Alzheimer's disease," said Bill Thies, scientific director of the Alzheimer's Association.

Researchers testing one drug, Baxter International Inc.'s Gammagard, are expected to provide a detailed progress report on 16 of 24 patients who were enrolled in an earlier study.

"Their cognitive function, their memory function has remained stable over that period of time," said Thies. "That's something we would not expect for people with Alzheimer's disease."

Drug infusions

Gammagard is intravenous immune globulin, or IVIG, that uses multiple antibodies from blood.

Treating Alzheimer's with IVIG would cost $2,000 US to $5,000 US every two weeks, depending on the patient's weight, said Dr. Norman Relkin, head of a memory disorders program at New York-Presbyterian Hospital/Weill Cornell Medical Center. He consults for some drug makers and has patents ontests that measure amyloid.

Neurologist Dr. Howard Feldman of the University of British Columbia in Vancouver said he'd interpret the Gammagard results very cautiously because they may not be statistically significant.

"We may not have the right drug, we may not have the right timing, but we're on the right pathway," Feldman said.

If not, Dr. Ronald Petersen, director of the Mayo Clinic's Alzheimer's Disease Research Center in Rochester, Minn., worries what could happento the field.

"If these studies are all flat, dead negative, then I think we're in trouble, the field is in trouble because I think a lot of other companies are going to bail on this notion," Pederson said.

Other drug results are expected next month.

Bapineuzumab (bap-ih-NOOZ-uh-mab), by Pfizer Inc. and Johnson & Johnson's Janssen Alzheimer Immunotherapy unit, and solanezumab (sol-ah-NAYZ-uh-mab), by Eli Lilly & Co, arealso undergoing testing. Like Gammagard, they're given by periodic intravenous infusions.

Researchers are testing for memory and cognitive improvements and they're using brain imaging and spinal fluid tests to check if the drugs are hitting their target, Petersen said.