Medical Research; FDA Approves "Amyvid" to Help Diagnose Alzheimer's Disease.

This blog reviews the data discussed on the April 13, 2012 Let's Talk Medical with Doctor Gigi.  You can check out the podcast via if you prefer the spoken word.

Medical Research:

Skip noted that he had heard advertisements for healthy subjects to do cancer-related research, & wondered how in depth the research could be if they simply wanted "healthy" subjects.  In all fairness, some research is done simply to look for trends or even for genetic markers, so they do need large groups of people to participate, & generally all they need is a blood sample &/or a questionnaire completed.  Others trials involve medications or equipment, thus they are more stringent.  All participation in trials is considered voluntary, as no one can make you participate in medical research!

Regardless of the study, all clinical trials are over-seen by the FDA, which is of course a part of our government.  They don't care what is done to a patient or person during a trial, but they do care that the patient's rights & welfare are protected.  To that end, they care mostly about the "Informed Consent."  This is the paper which tells you who sponsors the study, who the doctors are & how to contact them in case of an emergency, what the drug(s) is that is under study, what the known side-effects of that drug are, what is required in the way of appointments & data collection, as well as blood collections & procedures that are to be done.  After reading this informed consent, the FDA considers you to be educated or informed, & after you sign it, they consider that you have given consent to proceed in the trial.  Thus the paper is called an "informed consent."  As stated before, the FDA doesn't care so much about the specifics of a study (or what we do to you), but they do want to be sure you knew what we planned to do to you & that with knowledge you agree to continue.  Of course, you can always leave a study at any time by "withdrawing consent," which means you no longer wish to be in the study.  The doctor tries hard to select people who will complete the trial, as usually data is not useful unless the patient completes the study.  Those who do not complete are a financial loss to the pharmaceutical company, but of course everybody has the right to leave a study at any time... and of course, as a physician, my job is to take care of the patient first, & the study second.  This means that my primary responsibility is to the patient's health, not to the pharmaceutical company!

To get into any trial, the patient must have all the inclusion criteria & none of the exclusion criteria.  These are a variety of factors which vary from study to study & which help identify appropriate people for the trial.  All information given to the study staff is evaluated to see if you can be included or need to be excluded.  These criteria are written in stone, & the study staff & doctor cannot make exceptions.  In fact we get in big trouble if we mess up on inclusion & exclusion criteria, so please be honest with all of your answers to our questions, especially as these criteria help protect you by keeping you out of studies which might be bad for your health!

Lastly, remember that if you decide to participate in a clinical trial, do your best to do everything exactly as they ask you to.  The FDA expects perfection, both from the patient & from the study staff.  To do less than that is to potentially get a bad drug to the market, or perhaps keep a good drug off the market!

FDA Approves "Amyvid" to Help Diagnose Alzheimer's Disease:

Speaking of clinical trials, as many of you know, I do clinical trials part-time.  I am proud to see that one of our clinical trials seems to have helped get a new PET scan dye to the market!  The FDA just approved Amyvid which is a product we studied at Meridien Research in St. Petersburg.

First, to understand the excitement surrounding this product you must first understand that Alzheimer's disease is not only very common, but it is a "diagnosis of exclusion."  This means that we cannot verify the diagnosis with a test, so instead we seek to exclude other diseases, & if none of them are present we presume that the patient has Alzheimer's.  Truly, the only way to confirm the diagnosis of Alzheimer's is to do an autopsy... not a very good option to say the least as it is then too late to treat the patient!  At autopsy they should find beta-amyloid which produces hard plaques which degrade the nerve cells (=neurons) of the brain.  This beta-amyloid is not found exclusively in Alzheimer's patient's brains, but it is considered a hallmark finding of the disease.

Amyvid is a dye which lights up beta-amyloid when given in conjunction with a PET scan.  Thus a PET scan with Amyvid can potentially differentiate Alzheimer's disease from other forms of dementia by identifying the hallmark abnormality noted in that disease.  Thus if the test shows beta-amyloid, the diagnosis of Alzheimer's is likely, whereas an absence of beta-amyloid would require further evaluation for other diseases.

As a side note, remember that if a person cannot hear or see properly this can make him appear demented or confused.  So be sure to check your loved ones' hearing & vision if you feel he is getting confused or forgetful!

Thanks again for your interest in what I have to say, & if you find it helpful, please share with your friends & family.  Also, consider being a "follower" so you will get further blogs when completed!  And don't forget the radio show on Fridays at 1:00PM Eastern time on WTAN 1340-AM in the St. Petersburg/Tampa area.  If you can't catch the station, find us on the web via where you can listen live, or check out the podcasts at any time!  We also need your questions & input, so get in touch with me:  If you feel the desire to talk to me live, call during the show:  (727)-441-3000 or toll-free at (866)-TAN-1340.

Have a great week, & here's to our health!

Doctor Gigi