Dr. Ronald Petersen, director of the Mayo Clinic's Alzheimer's Disease Research Center, agreed.
"The concern with this study is there has been attrition over time," so the people left in the study are the ones who did well whereas others may have died, he said. These early results "will just whet our appetites" for the bigger study's results, he said.
That 400-patient study, headed by Relkin, will end late this year, and results are expected early next year. Treating Alzheimer's with IVIG would cost $2,000 to $5,000 every two weeks, depending on the patient's weight, he estimated.
"We want to make clear that this is not an approved treatment as yet and we're not making any sensational claims," Relkin said.
Two other experimental Alzheimer's drugs are in late-stage studies that just ended; results are being analyzed now. They are:
—Bapineuzumab (bap-ih-NOOZ-uh-mab), by Pfizer Inc. and Johnson & Johnson's Janssen Alzheimer Immunotherapy unit.
—Solanezumab (sol-ah-NAYZ-uh-mab), by Eli Lilly & Co.
On Tuesday, J&J announced that results of two studies testing bapineuzumab will be presented at a neurology conference in Sweden in September. The main result is expected to be announced before then, as soon as it is known.
Alzheimer's info: http://www.alzheimers.gov
Alzheimer's Association: http://www.alz.org
Alzheimer's Association International Conference: http://www.alz.org/aaic/overview.asp
Marilynn Marchione can be followed at http://twitter.com/MMarchioneAP
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