FDA on new Alzheimer's test: No, or at least not yet
January 20th, 2011
06:11 PM ET

FDA on new Alzheimer's test: No, or at least not yet

A new test to detect or rule out Alzheimer’s is not quite ready for prime time, an FDA advisory panel said Thursday afternoon. The test, a type of PET scan developed by Avid Radiopharmaceuticals, is designed to detect the telltale buildups of amyloid plaque in the brain that signify Alzheimer’s disease. While PET scans aren’t new, this one uses a special radioactive marker known as florbetapir F 18 and developed under the brand name Amyvid. It’s meant to be used when a doctor suspects Alzheimer's; a negative test – meaning no detectable plaque – would tell the doctor to consider a different diagnosis.

While the test is considered safe, members of the FDA's Peripheral and Central Nervous System Drugs Advisory Committee said Avid needs to do more work training the medical professionals who would administer it. Panel members also voiced concern that there would be too many "false-positive" tests – in other words, too many patients told they have Alzheimer's when in fact they don't. Dr. James Tatum of the Hunter Holmes McGuire VA Hospital in Richmond cited data suggesting that in patients older than 80, as many as a third of "positive" test results would be wrong.

Tatum ended up voting in support of Amyvid, but by a vote of 16-3 his fellow panelists disagreed.

However, in a followup vote, by 16-0 (with three abstentions) the panel said the test should be approved if Avid can ensure proper training and labeling so that test results are consistent, as well as analyzed and interpreted accurately.

Maria Carrillo, senior director of medical and scientific relations at the Alzheimer's Association, said she expects the training concerns to be addressed and the test to be approved later this year. Carrillo said the test could could be a boon to research, as well as patient care.

"Right now we don't have evidence of what amyloid [plaque] in the brain means – when it starts, and when does it tip over into actual cognitive deficits," Carrillo said. "We need to follow people over time, and this could be the tool we use."

soundoff (32 Responses)
  1. varednek

    This is great

    January 21, 2011 at 08:12 | Report abuse | Reply
  2. bbbrooke

    I hope all you morons that are making jokes about this NEVER have to face the brutal truth of Alzheimers... although you deserve to see what you are mocking... it is a horrible, horrible disease.

    January 21, 2011 at 09:14 | Report abuse | Reply
    • Prophet

      it's a sad thing people... those who mock, I feel sorry for you, because it wont be you with the disease, it will be someone very dear and close to your heart, you'll see very soon.

      January 21, 2011 at 11:23 | Report abuse |
  3. Qi

    speaking of memory, why did G. Beck sell out and go over to the other side. Now he bows to Obama and sings his praises. Starts his news show with new world order music and will not even take calls on ground zero victory mosque. He has become a RINO!

    January 21, 2011 at 09:17 | Report abuse | Reply
  4. bluewhale

    I'm ecstatic! I'll be first in line to find out if I'm starting to have what has destroyed my mother's mind. I'm tired of looking over my shoulder every time I have a lapse of memory on anything. I'm 59 which is when my mother started showing signs. And for those who are going to say that I should simply live life to its fullest, you're naive, at best. My wife and I would surely change our life plans if we're going to have to face this disease.

    January 21, 2011 at 09:36 | Report abuse | Reply
  5. JasonB

    I wonder if this PET technique could be modified and used to study the progression of amyloid plaques over time. For the first time ever, we would be able to witness the progression of Alzheimer's from inside the brain and track which parts of the brain the plaques form and how they spread throughout brain tissue. Perhaps them we could learn to prevent aggregation if we were able to find a common denominator.

    January 21, 2011 at 10:20 | Report abuse | Reply
    • JM

      We actually know much of this already; I study AD right now and where plaques form the progression of plaque propagation is relatively well understood. Also, most humans die with amyloid plaques in their brain, and if you looked on autopsy at most people after they die they have AD pathology. The amount of plaques also poorly correlates or doesn't at all with the symptoms of AD, so it looks like whatever AD is, it is probably not only plaques.

      January 21, 2011 at 10:48 | Report abuse |
  6. Suzanne

    I really hope that this isn't just red-tape stalling. So often you hear rumors of big pharma deliberately holding back on life-saving drugs and tests because of the notion that curing a disease means you can make less money off of it.

    I hope that isn't true, and I hope – really do hope, as someone with a family history of Alzheimer's – that this test will be made available soon and that it will be accurate.

    January 21, 2011 at 10:23 | Report abuse | Reply
    • Joe

      I think, if anything, it's the government stalling, not pharma. The FDA has become so gun-shy because of the Celebrex fiasco that they require mountains of paperwork, regulation, etc to get things like this approved.

      What this type of test will do, while not curing or treating people with Alzheimer's, is hopefully identify people at the very early stages and allow patients and their families to make the necessary preparations for long-term care well in advance. Right now, it is still virtually impossible to treat AD once the plaques start to form.

      January 21, 2011 at 14:27 | Report abuse |
  7. Peter

    Why would pharma stall it if they don't really have any good meds now. They really are not making money on Alzheimer's yet.

    January 21, 2011 at 10:48 | Report abuse | Reply
  8. Ryan

    The problem, as mentioned, is there are people that will have a positive test that don't necessarily have Alzheimer's disease. It has nothing to do with any drug company holding off to make more money. If anything all the false positive tests will result in more meds being used that may not be needed and that may be a waste of money

    It is a huge step forward in Alzheimer's testing, but interpretation is not as straightforward as the mainstream media is making it out to be.

    January 21, 2011 at 10:50 | Report abuse | Reply
  9. Thatguy371

    This needs to be approved yesterday. Get with it FDA. We need early diagnosis and a cure. Don't wait until the baby boomers are heavy into retirement age, when by that time it will have become an epidemic. Do it now!

    January 21, 2011 at 10:50 | Report abuse | Reply
  10. Nik

    This is fantastic news in the research for Alzheimer's, we can finally have a true test for this disease! Coming from a family that has had to watch a loved one go through this horrible disease.

    January 21, 2011 at 10:56 | Report abuse | Reply
    • Nik

      with the hope of earlier detection, maybe they will be able to create better drugs to fight this.

      January 21, 2011 at 10:57 | Report abuse |
  11. Joe

    While this concept is great, and we do need a way to detect AD in it's early stages, I can see one major flaw. The presence of amyloid plaques does not necessarily mean a patient has AD. Everyone even those who are health produce amyloid within the brain. On top of that, if the presence of amyloid is found within the brain, there is no point to it. Once a patient begins to have plaque build up, it is too late to try to do anything. Presence of amyloid can only help to diagnose, but by looking for amyloid, you will not catch it early, rather amyloid is a late appearing plaque in the time course for AD.

    January 21, 2011 at 11:29 | Report abuse | Reply
  12. just a thought

    Without any availble treatments so far that slow the progression or cognitive decline in patients, I'm not sure I want to know whether I have amyloid in my brain. There are studies suggesting that stress plays a role in aggravating amyloid pathology so "knowing" about something that can't be stopped might be worse than ignorance.

    January 21, 2011 at 11:39 | Report abuse | Reply
    • bbbrooke

      I just read the book "Still Alice" and it talked about members of the family being tested to determine if they too carried the potential for AD. It really made me wonder if I would want to know or not. Like you said, if there is no cure or viable option to stall the progress of AD then would it be worth the anxiety of knowing... always wondering if forgetting something was just a normal "Oh crap" or if it was the early stages of AD.

      January 21, 2011 at 11:55 | Report abuse |
  13. bbbrooke

    It would be wonderful it they could come up with something to combat this disease. My father passed away in April after having fought AD. I watched him become a shell of who he was... he graduated top in his class at Princeton, ran his own business for years and up until AD took over he could still help my daughter with calculus and trig homework!

    January 21, 2011 at 11:46 | Report abuse | Reply
  14. Quekavayo

    Hope there is ever a cure for this devastating disease! hope that with this we come closer to a cure!

    January 21, 2011 at 12:02 | Report abuse | Reply
  15. Russ

    When it get approved, look for health insurance premiums to go up. The test will probably cost over $1000. Then, whatever is discovered, people will want treatment for. Additionally, a diagnosis of early Alzheimers will cause some to become depressed and others to take their lives. For some, it will be a positive thing, and they will get their lives in order. But, I fear, that for the vast majority, who discover they have Alzheimers, it's going to cause tremendous grief and family suffering. Some things are better not known until they manifest themselves.

    January 21, 2011 at 12:05 | Report abuse | Reply
  16. Joe

    The decision by the FDA to delay approval of this is yet another example of one of the major reasons that new medical technology and medications are more expensive. The need to satisfy every single requirement of Uncle Sam costs these companies millions of dollars, which ultimately is passed onto insurance companies and the consumer. It's the major reason that the vast majority of high-end medical research is done overseas.

    January 21, 2011 at 12:11 | Report abuse | Reply
  17. bbbrooke

    Must not have had preschool today jerk

    January 21, 2011 at 12:33 | Report abuse | Reply
  18. mirtelina


    January 21, 2011 at 15:07 | Report abuse | Reply
  19. No Moderators??

    It would be a nice change if CNN actually moderated these comments. Hopefully these morons will end up with the disease that they are making fun of... karma would really be pay back. But then again, their lives probably are better off not remembered any way.

    January 21, 2011 at 15:35 | Report abuse | Reply
  20. Supportthis

    This is wonderful. Together we can create the cure.

    January 23, 2011 at 17:46 | Report abuse | Reply
  21. Len Hudyma

    Just thought I would bring this to your attention…. The application is not seeking to have the scan used to confirm Alzheimer’s or dementia…. It is to indicate that there is no abeta plaque , which would indicate that the person DOES NOT have Alzheimer’s. This scan will have nothing to do with trying to get early screening for the disease, which is what the medical world is asking for. Here is the excerpt from the application.

    A closer examination of the application reveals a point that receives almost no mention elsewhere: that Avid's application actually does not seek approval to use the test to diagnose Alzheimer's disease. Rather, it seeks approval to use it to rule out the presence of amyloid plaques. If FDA eventually grants approval, presumably some doctors would use it for "off-label" purposes, such as testing people they already suspect have Alzheimer's or screening people with mild memory impairments.

    About Amyvid
    Amyvid is an imaging tool indicated for Positron Emission Tomography (PET) imaging of beta-amyloid plaque in the brain. It's being investigated for the potential use in ruling out Alzheimer's disease. The FDA Committee stated that a negative scan would be clinically useful in indicating that Alzheimer's pathology is unlikely to be the cause of a patient's cognitive decline.

    January 27, 2011 at 14:11 | Report abuse | Reply
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