Hello and welcome back to my podcast.
My name is Eric Valor and today I have a few different subjects to cover. I will cover the new ALS treatment recently approved by the FDA, the latest message from Hope Now For ALS, MAGIC in yeast cells, and trouble for stem cell therapies.
But first, I would like to make a personal announcement. Some of you may already know this, but I was recently accepted to the Academy of Neurology as a researcher. It’s not a huge deal but it’s nevertheless something I am proud to have on my CV.
Now, to business. My first item on the board is the first drug to be approved for ALS in 22 years.
In May of 2017, the FDA approved edaravone, also called Radicut or Radicava, for use in the United States. Edaravone was developed and originally approved for use in Japan in 2001 for protection from the effects of a type of stroke. Its MOA, or method of action, is as a scavenger of free radicals. These molecules have an unpaired electron in one of their atoms, making them extremely reactive with other molecules. The radicals at subject are called reactive oxygen species or ROS, produced as a byproduct of the mitochondria creating energy for the motor neurons. These molecules, when not properly controlled, cause significant damage to cellular structures. There have been many attempts to eliminate these ROSs as a treatment for ALS, but all previous attempts have failed.
There are some side effects resembling allergic reactions, from redness and itching up to anaphylaxis, which requires immediate emergency medical assistance or the person can perish). The incidence of serious adverse effects (SAEs) was low, with the most common, dysphagia or difficulty swallowing, occurring in 12% of patients. Milder adverse events occurred at the same rate as placebo.
The dosing regimen is 14 days of one infusion per day of 100 milliliters administered over one hour followed by 14 days with no infusions. Subsequent cycles are 10 days of infusions followed by 14 days without. Edaravone showed up to 33% slower progression in patients who were fewer than 2 years post-diagnosis, were still ambulatory, and could still feed, dress, and bathe themselves. Three out of four clinical trials of edaravone for ALS failed to meet clinical endpoints, but the fourth, when restricted to the PALS described previously, met its endpoints. What that means is that it seems effective only in people very early on in progression.
The second item on the agenda is the recent update which Hope NOW for ALS posted about its activity. On May 10, 2017, HNFA released a statement describing their May 1, 2017 meeting with key officials at FDA CDER. The statement also mentioned the approval of Radicava and how it is the first drug approved to treat ALS in 22 years. The main point of the HNFA statement was to indicate willingness by the FDA to consider updated clinical trial methods to make clinical trials more accurate and humane. It’s a hopeful message and indicates, along with the new approval of a treatment for ALS, that the FDA may be really changing how it sees and deals with life-threatening or fatal conditions.
Third, the ALZ Forum has a nice article on mitochondria making MAGIC. In a study published in the March 1st edition of Nature, a team from Johns Hopkins University describe mitochondria in yeast cells untangling misfolded cellular proteins before tearing them apart for recycling the components. The process was termed “mitochondria as guardian in cytosol” or MAGIC. Aggregated or misfolded proteins which become tangled in each other are known to be torn apart in cellular machinery called proteasomes. Without mechanisms for breaking down these aggregated proteins they would clog the entire cell like the white of a boiled egg. You can see the same process happen as you fry your breakfast in the morning. That would be very bad for the cell and ultimately us.
In MAGIC, these same aggregated proteins are imported into the intermembrane area, a small space between the outer and inner membranes of the mitochondria. There the proteins are untangled from each other, then passed into the inner mitochondria where the individual proteins are chopped up. When heat shock proteins in the cytosol of the cell aren’t working properly this puts more stress on the mitochondria which are already very hard at work creating energy for the neuron. Think of it like hauling a heavy trailer up a mountain road in your car. Your engine strains under the load, getting hotter and pumping more smoke out of the tailpipe. The “smoke” from the mitochondria is the ROSs. The authors further reported that this process also happens in human cells. If those holds true then it would tie together two critical factors of neurodegenerative disease: protein aggregation and mitochondrial dysfunction. That’s would be an important finding as it would further elucidate the mystery of ALS, Alzheimer’s, and Parkinson’s.
In another story, again from the ALZ Forum, it appears that significant efficacy differences exist between clinical-grade stem cell lines and their research-grade counterparts. The differences may explain why some clinical trials fail. Two studies in the February 14 edition of Stem Cell Reports (study 1 and study 2) suggest that the outcomes could have been anticipated if the production lines were animal-tested the same way as in preclinical studies. The two subject studies looked at the unsuccessful trials by StemCells Inc. of spinal injury treatment using neural precursor cells. The company reported that the cells remyelination and motor recovery in mice with spinal injury.
But in two different trials with the same cells expanded using the Good Manufacturing Process (GMP) standard, required for production for use in humans, the cells failed to demonstrate efficacy. When the same lines were later tested in mice for the subject studies, they matured at about half the rate as the research-grade cells and largely remained as undifferentiated clumps. In one study about 4 percent of the grafted cells continued to divide and in some cases extended neurites into the surrounding tissue. Obviously injecting undifferentiated stem cells is a very bad idea and no two stem cell lines are identical. Together these studies provide strong evidence for preclinical testing of clinical-grade cells prior to use in humans.
Finally, another announcement: Beginning with this podcast (and retroactively back to the prior podcast) the video portion will be included at the bottom of the transcript. This will make viewing easier for my blog readers.
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