Today a committee from the FDA is meeting to deliberate on the drug Exelon. It is already approved for treating mild dementia in people with Alzheimer’s disease. Thousands of prescriptions will be filled for it today. The big question is should the FDA approve it for people with Parkinson’s who have mild dementia?
This meeting is apt to take the better part of the day. Prior to the meeting, participants reviewed a “Briefing Document” of 202 pages, a “Background Document” of 16 pages, a “Clinical Review” of 93 pages and a “Statistical Review and Evaluation” of 93 pages. It is safe to say that there will be plenty to talk about.
Why are they going to all of this trouble? Usually, to get a drug approved for a new use, the FDA requires two distinct studies proving the drug is effective. Exelon’s manufacturer, Novartis, only has one so far. It is a convincing study. People with Parkinson’s related dementia improved significantly when they took Exelon. People on the placebo did not. However, the FDA is lacking a second study. Second studies are important. They help flush out biases and exaggerations that occurred in the first study.
So, do you leave the Parkinson’s population without an option for mild dementia, while you wait for the study? Right now they currently have no approved options. (Doctors can prescribe the drug “off label” but many will not.) In contrast, there are a few different drugs approved for Alzheimer’s.
Part II of the problem: Dementia is complex. There are many causes for dementia in Parkinson’s disease. Some of the causes overlap with dementia seen in Alzheimer’s. However, some PD dementia comes from phenomenon that is rare in Alzheimer’s. Furthermore, people with Alzheimer’s experience dementia in different ways then do people with Parkinson’s. So, the medical community it not sure how appropriate Exelon is for people with Parkinson’s.
Of course people with Parkinson’s, their family members and their physicians want a drug to treat mild dementia. There isn't one for PD right now. However, they want a solution that will be effective for most people. So, let’s wait and see what we learn. We will likely post more information in the next 24 hours about the conclusions of the meeting.
Other PD News
Right now a hot topic in Parkinson’s research is the relationship between mitochondria damage in neurons and Parkinson’s disease. Mitochondria are kind of like the battery pack that provides energy to cells. Last week a post addressed a genetic event within mitochondria that could be part of the sequence of events that causes Parkinson’s disease. This story about findings at the University of Virginia introduces a new idea. We say “idea”, because it is one of those theories that may pan out. Or in the words of one of the researchers, "Such treatment is hypothetical at this point, but it is rational."
The theory is that oxygen free radicals damage the mitochondria. "If we could soak up the free radicals in mitochondria, then [it] could repair itself," says University of Virginia neurologist, Jim Bennett.
Finally, there is a good article about stem cells today at this link. However, we need to cover stem cells in a different blog, and in a more complete manner. A lot of interesting stuff is happening here. There is also a good amount of confusion about whether it is legal to do research with stem cells. Short answer: It is legal to do research with stem cells and to create stem cells. However, federal funds are only available to a small group of stem cell lines or collections.
As always, we encourage your email at mnilsen@myparkinsonsinfo.com. We read each one, and respond to most of them as well. We enjoy the dialogue.