The great ice hockey player Wayne Gretzky once said “A good hockey player plays where the puck is. A great hockey player plays where the puck is going to be” (the original quote actually came from his father, Walter).
At the start of each year, it is a useful practise to layout what is planned for the next 12 months. This can help us better anticipate where ‘the puck’ will be, and allow us to prepare for things further ahead.
2017 was an incredible year for Parkinson’s research, and there is a lot already in place to suggest that 2018 is going to be just as good (if not better).
In this post, we will lay out what we can expect over the next 12 months with regards to the Parkinson’s-related clinical trials research of new therapies.
Charlie Munger (left) and Warren Buffett. Source: Youtube
Many readers will be familiar with the name Warren Buffett.
The charming, folksy “Oracle of Omaha” is one of the wealthiest men in the world. And he is well known for his witticisms about investing, business and life in general.
Warren Buffett. Source: Quickmeme
He regularly provides great one liners like:
“We look for three things [in good business leaders]: intelligence, energy, and integrity. If they don’t have the latter, then you should hope they don’t have the first two either. If someone doesn’t have integrity, then you want them to be dumb and lazy”
“Work for an organisation of people you admire, because it will turn you on. I always worry about people who say, ‘I’m going to do this for ten years; and if I really don’t like it very much, then I’ll do something else….’ That’s a little like saving up sex for your old age. Not a very good idea”
“Choosing your heroes is very important. Associate well, marry up and hope you find someone who doesn’t mind marrying down. It was a huge help to me”
Mr Buffett is wise and a very likeable chap.
Few people, however, are familiar with his business partner, Charlie Munger. And Charlie is my favourite of the pair.
At the end of each year, it is a useful practise to review the triumphs (and failures) of the past 12 months. It is an exercise of putting everything into perspective.
2017 has been an incredible year for Parkinson’s research.
And while I appreciate that statements like that will not bring much comfort to those living with the condition, it is still important to consider and appreciate what has been achieved over the last 12 months.
In this post, we will try to provide a summary of the Parkinson’s-related research that has taken place in 2017 (Be warned: this is a VERY long post!)
The number of research reports and clinical trial studies per year since 1817
As everyone in the Parkinson’s community is aware, in 2017 we were observing the 200th anniversary of the first description of the condition by James Parkinson (1817). But what a lot of people fail to appreciate is how little research was actually done on the condition during the first 180 years of that period.
The graphs above highlight the number of Parkinson’s-related research reports published (top graph) and the number of clinical study reports published (bottom graph) during each of the last 200 years (according to the online research search engine Pubmed – as determined by searching for the term “Parkinson’s“).
PLEASE NOTE, however, that of the approximately 97,000 “Parkinson’s“-related research reports published during the last 200 years, just under 74,000 of them have been published in the last 20 years.
That means that 3/4 of all the published research on Parkinson’s has been conducted in just the last 2 decades.
And a huge chunk of that (almost 10% – 7321 publications) has been done in 2017 only.
So what happened in 2017? Continue reading
In the 1990, scientists identified some fruits that they suspected could give people Parkinson’s.
These fruit are bad, they reported.
More recently, researchers have identified chemicals in that exist in those same fruits that could potential be used to treat Parkinson’s.
These fruit are good, they announce.
In today’s post, we will explain why you should avoid eating certain members of the Annonaceae plant family and we will also look at the stream of research those plants have given rise to which could provide a novel therapy for Parkinson’s.
Guadeloupe. Source: Bluefoottravel
In the late 1990s, researchers noticed something really odd in the French West Indies.
It had a very strange distribution of Parkinsonisms.
What are Parkinsonisms?
‘Parkinsonisms’ refer to a group of neurological conditions that cause movement features similar to those observed in Parkinson’s disease, such as tremors, slow movement and stiffness. The name ‘Parkinsonisms’ is often used as an umbrella term that covers Parkinson’s disease and all of the other ‘Parkinsonisms’.
Parkinsonisms are generally divided into three groups:
- Classical idiopathic Parkinson’s disease (the spontaneous form of the condition)
- Atypical Parkinson’s (such as multiple system atrophy (MSA) and Progressive supranuclear palsy (PSP))
- Secondary Parkinson’s (which can be brought on by mini strokes (aka Vascular Parkinson’s), drugs, head trauma, etc)
Some forms of Parkinsonisms that at associated with genetic risk factors, such as juvenile onset Parkinson’s, are considered atypical. But as our understanding of the genetics risk factors increases, we may find that an increasing number of idiopathic Parkinson’s cases have an underlying genetic component (especially where there is a long family history of the condition) which could alter the structure of our list of Parkinsonisms.
So what was happening in the French West Indies?
Antidepressants are an important class of drugs in modern medicine, providing people with relief from the crippling effects of depression.
Recently, research has suggested that some of these drugs may also provide benefits to people suffering from Parkinson’s disease. But by saying this we are not talking about the depression that can sometimes be associated with this condition.
This new research suggests anti-depressants are actual providing neuroprotective benefits.
In today’s post we will discuss depression and its treatment, outline the recent research, and look at whether antidepressants could be useful for people with Parkinson’s disease.
It is estimated that 30 to 40% of people with Parkinson’s disease will suffer from some form of depression during the course of the condition, with 17% demonstrating major depression and 22% having minor depression (Click here to read more on this).
This is a very important issue for the Parkinson’s community.
Depression in Parkinson’s disease is associated with a variety of poor outcomes not only for the individuals, but also for their families/carers. These outcomes can include greater disability, less ability to care for oneself, faster disease progression, reduced cognitive performance, reduced adherence to treatment, worsening quality of life, and increased mortality. All of which causes higher levels of caregiver distress for those supporting the affected individual (Click here to read more about the impact of depression in early Parkinson’s).
What is depression?
Wikipedia defines depression as a “state of low mood and aversion to activity that can affect a person’s thoughts, behaviour, feelings, and sense of well-being” (Source). It is a common mental state that causes people to experience loss of interest or pleasure, feelings of guilt or low self-worth, disturbed sleep or appetite, low energy, and poor concentration.
Importantly, depression can vary significantly in severity, from simply causing a sense of melancholy to confining people to their beds.
What causes depression?
Recently I was invited to speak at the 6th Annual East Midlands Parkinson’s Research Support Network meeting at the Link Hotel, in Loughborough. The group is organised and run by the local Parkinson’s community and supported by Parkinson’s UK. It was a fantastic event and I was very grateful to the organisers for the invitation.
They kindly gave me two sessions (20 minutes each) which I divided into two talks: “Where we are now with Parkinson’s research?” and “Where we are going with Parkinson’s research?”. Since giving the talk, I have been asked by several attendees if I could make the slides available.
The slides from the first talk can be found by clicking here.
I have also made a video of the first talk with a commentary that I added afterwards. But be warned: my delivery of this second version of the talk is a bit dry. Apologies. It has none of my usual dynamic charm or energetic charisma. Who knew that talking into a dictaphone could leave one sounding so flat.
Anyways, here is the talk – enjoy!
I hope you find it interesting. When I have time I’ll post the second talk.
Nuclear receptor related 1 protein (or NURR1) is a protein that is critical to the development and survival of dopamine neurons – the cells in the brain that are affected in Parkinson’s disease.
Given the importance of this protein for the survival of these cells, a lot of research has been conducted on finding activators of NURR1.
In today’s post we will look at this research, discuss the results, and consider issues with regards to using these activators in Parkinson’s disease.
Comet Hale–Bopp. Source: Physics.smu.edu
Back in 1997, 10 days after Comet Hale–Bopp passed perihelion (April 1, 1997 – no joke; perihelion being the the point in the orbit of a comet when it is nearest to the sun) and just two days before golfer Tiger Woods won his first Masters Tournament, some researchers in Stockholm (Sweden) published the results of a study that would have a major impact on our understanding of how to keep dopamine neurons alive.
Dopamine neurons are one group of cells in the brain that are severely affected by Parkinson’s disease. By the time a person begins to exhibit the movement symptoms of the condition, they will have lost 40-60% of the dopamine neurons in a region called the substantia nigra. In the image below, there are two sections of brain – cut on a horizontal plane through the midbrain at the level of the substantia nigra – one displaying a normal compliment of dopamine neurons and the other from a person who passed away with Parkinson’s demonstrating a reduction in this cell population.
The dark pigmented dopamine neurons in the substantia nigra are reduced in the Parkinson’s disease brain (right). Source:Memorangapp
The researchers in Sweden had made an amazing discovery – they had identified a single gene that was critical to the survival of dopamine neurons. When they artificially mutated the section of DNA where this gene lives – an action which resulted in no protein for this gene being produced – they generated genetically engineered mice with no dopamine neurons:
Title: Dopamine neuron agenesis in Nurr1-deficient mice
Authors: Zetterström RH, Solomin L, Jansson L, Hoffer BJ, Olson L, Perlmann T.
Journal: Science. 1997 Apr 11;276(5310):248-50.
The researchers who conducted this study found that the mice with no NURR1 protein exhibited very little movement and did not survive long after birth. And this result was very quickly replicated by other research groups (Click here and here to see examples)
So what was this amazing gene called?
This week a biotech company called Voyager Therapeutics announced the results of their ongoing phase Ib clinical trial. The trial is investigating a gene therapy approach for people with severe Parkinson’s disease.
Gene therapy is a technique that involves inserting new DNA into a cell using a virus. The DNA can help the cell to produce beneficial proteins that go on help to alleviate the motor features of Parkinson’s disease.
In today’s post we will discuss gene therapy, review the new results and consider what they mean for the Parkinson’s community.
On 25th August 2012, the Voyager 1 space craft became the first human-made object to exit our solar system.
After 35 years and 11 billion miles of travel, this explorer has finally left the heliosphere (which encompasses our solar system) and it has crossed into the a region of space called the heliosheath – the boundary area that separates our solar system from interstellar space. Next stop on the journey of Voyager 1 will be the Oort cloud, which it will reach in approximately 300 years and it will take the tiny craft about 30,000 years to pass through it.
Where is Voyager 1? Source: Tampabay
Where is Voyager actually going? Well, eventually it will pass within 1 light year of a star called AC +79 3888 (also known as Gliese 445), which lies 17.6 light-years from Earth. It will achieve this goal on a Tuesday afternoon in 40,000 years time.
Gliese 445 (circled). Source: Wikipedia
Remarkably, the Gliese 445 star itself is actually coming towards us. Rather rapidly as well. It is approaching with a current velocity of 119 km/sec – nearly 7 times as fast as Voyager 1 is travelling towards it (the current speed of the craft is 38,000 mph (61,000 km/h).
Interesting, but what does any of that have to do with Parkinson’s disease?
Well closer to home, another ‘Voyager’ is also ‘going boldly where no man has gone before’ (sort of).
In this post I review recently published research describing interesting new gene therapy tools.
“Gene therapy” involved using genetics, rather than medication to treat conditions like Parkinson’s disease. By replacing faulty sections of DNA (or genes) or providing supportive genes, doctors hope to better treat certain diseases.
While we have ample knowledge regarding how to correct or insert genes effectively, the problem has always been delivery: getting the new DNA into the right types of cells while avoiding all of the other cells.
Now, researchers at the California Institute of Technology may be on the verge of solving this issue with specially engineered viruses.
Gene therapy. Source: yourgenome
When you get sick, the usual solution is to visit your doctor. They will prescribe a medication for you to take, and then all things going well (fingers crossed/knock on wood) you will start to feel better. It is a rather simple and straight forward process, and it has largely worked well for most of us for quite some time.
As the overall population has started to live longer, however, we have become more and more exposed to chronic conditions which require long-term treatment regimes. The “long-term” aspect of this means that some people are regularly taking medication as part of their daily lives. In many cases, these medications are taken multiple times per day.
An example of this is Levodopa (also known as Sinemet or Madopar) which is the most common treatment for the chronic condition of Parkinson’s disease. When you swallow your Levodopa pill, it is broken down in the gut, absorbed through the wall of the intestines, transported to the brain via our blood system, where it is converted into the chemical dopamine – the chemical that is lost in Parkinson’s disease. This conversion of Levodopa increases the levels of dopamine in your brain, which helps to alleviate the motor issues associated with Parkinson’s disease.
Levodopa. Source: Drugs
This pill form of treating a disease is only a temporary solution though. People with Parkinson’s disease – like other chronic conditions – need to take multiple tablets of Levodopa every day to keep their motor features under control. And long term this approach can result in other complications, such as Levodopa-induced dyskinesias in the case of Parkinson’s.
Yeah, but is there a better approach?
Some researchers believe there is. But we are not quite there yet with the application of that approach. Let me explain:
Exciting new last week from a small biotech company called Voyager Therapeutics which is using gene therapy to treat neurodegenerative disease. Their primary product (VY-AADC01) is focused on Parkinson’s disease and the initial results look very positive.
The press release has indicates that the treatment is well tolerated and has beneficial effects on the subject’s motor functions. This last part is very interesting as the trial is being conducted on people with advanced Parkinson’s disease.
In today’s post, we’ll review the technology and what the results mean.
Gene therapy. Source: HuffingtonPost
In Parkinson’s disease, we often talk about the loss of the dopamine neurons in the midbrain as a cardinal feature of the disease. When people are diagnosed with Parkinson’s disease, they have usually lost approximately 50-60% of the dopamine neurons in an area of the brain called the substantia nigra.
The dark pigmented dopamine neurons in the substantia nigra are reduced in the Parkinson’s disease brain (right). Source: Memorangapp
The midbrain is – as the label suggests – in the middle of the brain, just above the brainstem (see image below). The substantia nigra dopamine neurons reside there.
Location of the substantia nigra in the midbrain. Source: Memorylossonline
The dopamine neurons of the substantia nigra generate dopamine and release that chemical in different areas of the brain. The primary regions of that release are areas of the brain called the putamen and the Caudate nucleus. The dopamine neurons of the substantia nigra have long projections (or axons) that extend a long way across the brain to the putamen and caudate nucleus, so that dopamine can be released there.
The projections of the substantia nigra dopamine neurons. Source: MyBrainNotes
In Parkinson’s disease, these ‘axon’ extensions that project to the putamen and caudate nucleus gradually disappear as the dopamine neurons of the substantia nigra are lost. When one looks at brain sections of the putamen after the axons have been labelled with a dark staining technique, this reduction in axons is very apparent over time, especially when compared to a healthy control brain.
The putamen in Parkinson’s disease (across time). Source: Brain
Previously we have discussed replacing the loss dopamine by transplanting dopamine producing cells into the putamen (click here to read that post), but some researchers now believe that this is not necessary. Instead they have proposed using gene therapy for Parkinson’s disease.
What is gene therapy?
The gene therapy involves inducing cells to produce proteins that they usually do not. This is usually done using genetically modified viruses which have had all the disease causing component removed, allowing us to use the virus as an efficient delivery system. Viruses by their very nature are very good at infecting cells, so if we remove the disease causing components, what is left is a very effective delivery system. Taking this approach one step further, we could next take genes involved with dopamine synthesis and insert them into our empty virus. By then injecting this virus into the brain, we could produce dopamine in any infected cells (it’s slightly more complicated than that, but you get the basic idea).
Gene therapy for Parkinson’s disease. Source: Wiki.Epfl
This approach demonstrated amazing results in preclinical studies in the lab, but the transition to the clinic has not been easy (click here for a good review of the field).
What has been done in the clinic for gene therapy and Parkinson’s disease?
The first clinical attempt at gene therapy for Parkinson’s disease involved injecting a virus containing a gene called glutamic acid decarboxylase (GAD), which is an enzyme involved in the production of a chemical called GABA. The virus was injected into an area of the brain called the subthalamic nucleus, which becomes over-active in Parkinson’s disease. By ectopically producing GAD in the subthalamic nucleus, researchers were able to reduce the level of activity (this is similar to deep brain stimulation in Parkinson’s disease which modulates the activity of the subthalamic nucleus). The clinical trials for GAD produced modest results. The virus was well tolerated, but the clinical effect was limited.
Another clinical trial attempted to cause cells in the putamen to produce a chemical called neurturin (which is very similar to GDNF – we have previously written about GDNF, click here to read that post). The goal of the study was to prove neuroprotection and regeneration to the remaining dopamine neurons, by releasing neurturin in the putamen. Subjects were injected in the putamen with the virus and then the participants were followed for 15 months. Unfortunately, this study failed to demonstrate any meaningful improvement in subjects with Parkinson’s disease.
So what were the results of the trial?
Voyager Therapeutics‘s gene therapy product, VY-AADC01 is an adeno associated virus that carries a gene called Aromatic L-amino acid decarboxylase (or AADC).
AAV Viruses. Source: HuffingtonPost
Yeah, I know: what is AADC?
AADC is the enzyme that converts L-dopa into dopamine. L-dopa can be naturally produced in the brain from Tyrosine that is absorbed from the blood. It is also the basic component of many treatments for Parkinson’s disease.
The production of dopamine. Source: Slideplayer
By injecting VY-AADC01 into the putamen of people with advanced Parkinson’s disease, Voyager is hoping to alleviate the motor features of the condition by allowing the brain to produce a constant supply of dopamine in the exact location that is missing the dopamine (remember, the putamen is where dopamine is released). This approach will not cure the disease, but it may make life a lot easier for those affected by it.
The phase 1b clinical trial was designed to assess whether the virus had any negative side effects in humans. After the subjects were injected in the brain with VY-AADC01, they were assessed at six and twelve months after the surgery. The results suggest that the virus was well tolerated and resulted in increased AADC enzyme activity, enhanced response to L-dopa treatment, and clinically meaningful improvements in various measures of patients’ motor function (44% improvement in ‘off medication’ measures and 55% improvement in ‘on medication’ measures).
The company currently has 2 groups of subjects injected with the virus (two different concentrations) and they are looking to have a third group injected in early 2017. Phase 2 trials are planned to begin in late 2017.
What does it all mean?
They are also interesting results because the subjects involved in the study all have advanced Parkinson’s disease (the average time since diagnosis in the subject was 10 years). So it is very positive news to see beneficial effects in later stage subjects.
Our ability to delivery of genes to different locations is a symbol of how far we have come with our understanding of biology. The fact that this knowledge is now having a positive impact in the medical world is very exciting. Gene therapy is one treatment approach that we here at SoPD are very excited about and watching very closely.
The banner for today’s post was sourced from Voyager Therapeutics
We learned today that the phase 2 GDNF clinical trial in Bristol (UK) has failed to meet the primary efficacy end point. That is to say, the initial results suggest that the drug has not worked. In this post we will review what we know and discuss what will happen next.
GDNF was pumped into the striatum (green area). Source: Bankiewicz lab
We have previously discussed GDNF and Parkinson’s disease (Click here to read that post). This drug was considered the great hope for Parkinson’s disease and a lot was riding on the results. Today’s announcement is extremely unwelcomed news, but it is not necessarily the end of the road for GDNF.
What is GDNF?
Glial cell-derived neurotrophic factor (or GDNF) is a neurotrophic factor (neurotrophic = Greek: neuron – nerve; trophikós – pertaining to food/to feed). It is a chemical produced in the brain. GDNF has previously been found to have miraculous effects on some of the neurons in the brain that are most affected by Parkinson’s disease (particularly the dopamine neurons).
Given the amazing results in laboratories around the world, clinical trials were set up for people with Parkinson’s disease. The first study had astounding results, but a larger follow up study failed to replicate those results and so a third GDNF clinical trial was initiated: the Bristol GDNF study
What is the Bristol GDNF study?
The Bristol GDNF study run by the the North Bristol NHS Trust, was funded by Parkinson’s UK, with support from The Cure Parkinson’s Trust. The company MedGenesis Therapeutix supplied the GDNF and additional project resources/funding. MedGenesis Therapeutix itself has funding support from the Michael J. Fox Foundation for Parkinson’s Research.
The study involved participants having GDNF (or a placebo drug) pumped directly into their brains, into an area called the putamen. The putamen is where the greatest loss of dopamine occurs in people with Parkinson’s disease.
All together there were 41 people with Parkinson’s disease enrolled in the clinical trial. The trial was divided into two phases and the first of those is now complete. During the first phase 35 participants received either GDNF or a placebo drug over 9-months in a double blind fashion
What does double blind mean?
It means that neither the researchers nor the participants know which drug they are receiving. Everyone is ‘blind’ to the treatment. Single blind studies involve the researchers being aware of the treatment allocation, but the participants are blind. Single blind studies can be affected by what is called ‘investigator bias’ – where the investigators start to think that they see an effect when there may not be an effect. Double blind is considered the gold standard, but there are problems with this type of study as well.
If phase one has finished what is phase two of the trial?
The second phase of the study will involve all participants receiving GDNF. This part is already underway.
What was the “primary efficacy end point”?
The press release from the company behind the study, MedGenesis, suggested that:
‘The primary endpoint of the study is the percentage change from baseline in the practically defined OFF-state Unified Parkinson’s Disease Rating Scale (UPDRS) motor score (part III) after nine months of double-blind treatment’
With the limited information we currently have, we are assuming that the researchers were looking for a significant improvement in the motor symptoms rating scale (‘UPDRS’) of the subjects when compared to how they were at the start of the trial (‘baseline’). The subject’s motor features were assessed during periods when they were not taking their medication (‘OFF-state’), and the initial indications are that the researchers failed to see any improvement.
Is this negative result the end of the world?
NO. Most definitely not.
There are many reasons why the trial may have failed to achieve its primary end point, and the researchers have emphasized that they need time to analyse all of the results. It will be interesting to see the final analysis (and we will summarise it here when it is available – end of 2016 apparently).
It will also be important to follow up the participants to determine if there are any delayed positive outcomes. It may take longer than 9 months to see improvements (fetal transplant studies, for example, usually require 2-3 years before improvements are observed).
Maybe GDNF just needs a bit more time. We will keep you updated as more information comes to hand.