Athena Neurosciences Inc. is introducing today the first diagnostictests specific to Alzheimer's disease, giving neurologists the tools totell whether a patient has the disease.
"For the first time there is a test that can specifically diagnoseAlzheimer's by a process of inclusion as opposed to ruling out the 50other causes of dementia," said Eric Liebler, director of externalrelations at Athena and product manager for the tests, called theADmark Assays. "We're very excited to see the first fruits of ourscientific efforts in Alzheimer's become available to neurologists."
The ADmark Assays are two separate tests, each of which works in60 percent or more of diagnoses. One test determines the levels of theTau protein and beta-amyloid peptide (Ab42) in cerebrospinal fluid.The other diagnostic determines the Apolipoprotein (ApoE)genotype. The tests aren't meant to be predictive; rather they areuseful only in symptomatic patients.
If the first test shows high levels of Tau and low Ab42, "it means youdo indeed have Alzheimer's disease," Liebler said. "If there is highAb42 and low Tau, Alzheimer's disease is not the cause ofdementia." Both are accurate at least 95 percent of the time, he said.Tests revealing low-low or high-high levels of the proteins do notprovide diagnostic benefit.
Tau levels correlate to neurofibrillary tangles and Ab42 to plaques inthe brain, the pathological hallmarks of Alzheimer's.
The ApoE test determines the genotype _ expressed as E2, E3 orE4 _ inherited from each parent. In patients with dementia an E3-E4or particularly E4-E4 genotype indicates strongly that the condition iscaused by Alzheimer's.
Athena, of South San Francisco, is announcing the introduction of theproducts today in San Francisco at the American Academy ofNeurology's Annual Conference. The company's 54-person salesforce will actively target about 4,000 of the 7,000 U.S. neurologists.
There are about 4 million people with the degenerative brain disorderin the U.S. and another 500,000 people who get the disease eachyear. Alzheimer's leads to progressive dementia, characterized bymemory loss and impaired judgment, thinking, speech andorientation.
Currently physicians determine dementia is caused by Alzheimer'sfirst by ruling out other potential causes, which produce similarsymptoms. Confirmation is available only though an autopsy or brainbiopsy. ADmark Assays together can rule in or out Alzheimer's with95 percent accuracy in 60 percent of patients older than 60 who havedementia.
The ApoE test will sell for $195. The Tau and Ab42 test for $390.Together the tests run $495.
While there is no treatment for Alzheimer's, knowing someone'sdementia is caused by the disease will benefit the patient, physiciansand family members, Liebler said. Additional diagnostic tests couldbe avoided, neurologists could better manage a patient's treatment,drug reaction problems would be reduced and family members wouldbe more certain of the medical and financial burdens they face. It alsowould help identify those best suited to participate in clinical trials.
Alzheimer's disease has been the focus of Athena since its founding10 years ago. The company has a transgenic mouse model of thedisease and a research collaboration with Indianapolis-based Eli Lillyand Co. dating to 1988, as well as other programs in the area.
Liebler said the first candidates from the Lilly collaboration may beselected by the end of the year.
Last week Athena and Athlone, Ireland-based Elan Corp. plcannounced a deal in which Athena agreed to a buyout by Elan formore than $600 million. n
-- Jim Shrine
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