This post is a game of two halves.
The first half will explain the concept of a surgical procedure for Parkinson’s called ‘subthalamic deep brain stimulation‘, in which doctors permenantly implant electrodes into the brain to stimulate a region – the subthalamic nucleus. By stimulating this region with electrical impulses, doctors can provide a better quality of life (in most cases) to people with severe features of Parkinson’s.
In the second half of this post, we will look at an approach to doing the same thing,… but without the electrodes.
Rather, researchers are using gene therapy.
In today’s post, we will discuss what deep brain stimulation is, what gene therapy is, and how the gene therapy approach is having a different kind of impact on the brain to that of deep brain stimulation.
Welcome to the first half of today’s post.
It begins with you asking the question:
What is deep brain stimulation?
Deep brain stimulation (or DBS) is a treatment method that involves embedding electrodes into the brain to help modulate the brain activity involved in movement.
It is a prodcedure that is usually offered to people with Parkinson’s who have excessive tremor or debilitating dyskinesias.
First introduced in 1987, deep brain stimulation consists of three components: the pulse generator, an extension wire, and the leads (which the electrodes are attached to). All of these components are implanted inside the body. The system is turned on, programmed and turned off remotely.
This week a biotech company called Voyager Therapeutics provided an update regarding a gene therapy approach for people with severe Parkinson’s.
Gene therapy is an experimental therapeutic approach that involves inserting new DNA into cells using a virus. The introduced DNA can help a cell to produce proteins that it usually wouldn’t produce, and this can help to alleviate the motor features of Parkinson’s.
In today’s post we will discuss what gene therapy is, what Voyager Therapeutics is trying to do, and outline what their update reported.
There are 4 phases to the clinical trial process of testing new treatment for use in humans:
- Phase I determines if a treatment is safe in humans (this is conducted in an ‘open label’ manner)
- Phase II ‘double blindly’ assesses in a small cohort of subjects if the treatment is effective
- Phase III involves randomly and blindly testing the treatment in a very large cohort of patients
- Phase IV (often called Post Marketing Surveillance Trials) are studies conducted after the treatment has been approved for clinical use
(‘Open label’ refers to both the investigator and the participants in a study knowing what treatment is being administered; while ‘double blind’ testing refers to studies in which the participants and the investigators do not know whether the participant is receiving the active treatment or an inert control treatment until the end of the study).
Based on the successful completion of their Phase I clinical trials for their gene therapy treatment called VY-AADC (Click here to read more about this), Boston-based biotech firm Voyager Therapeutics approached the US Food and Drug Administration (FDA) with the goal of shifting their clinical trial programme into Phase II testing.
What is gene therapy?
Today biotech company Voyager Therapeutics announced an update on their ongoing phase Ib clinical trial. The trial is evaluating the safety and tolerance of a gene therapy approach for people with advanced Parkinson’s.
Gene therapy is a technique that involves inserting new DNA into a cell using viruses. In this clinical trial, the virally delivered DNA helps the infected cell to produce dopamine in order to alleviate the motor features of Parkinson’s.
In today’s post we will discuss what gene therapy is, review the new results mentioned in the update, and look at other gene therapy approaches for Parkinson’s.
Voyager Therapeutics is a clinical-stage gene therapy company that is focused on treatments for neurological conditions, such as Parkinson’s. Today the company announced an update of their ongoing Phase 1b trial of their product VY-AADC01 (Click here to see the press release).
VY-AADC01 represents a new class of treatment for Parkinson’s, as it is a form of gene therapy.
What is gene therapy?
The gene therapy involves introducing a piece of DNA into a cell which will cause the cell to produce proteins that they usually do not (either by nature or by mutation). The DNA is artificially inserted into cells and the cell’s protein producing machinery does the rest.
How does gene therapy work?
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
Last week, as everyone was preparing for Christmas celebrations, researchers at the pharmaceutic company Novartis published new research on a gene that is involved with Parkinson’s, called PARKIN (or PARK2).
They used a new gene editing technology – called CRISPR – to conduct a large screening study to identify proteins that are involved with the activation of PARKIN.
In today’s post we will look at what PARKIN does, review the research report, and discuss how these results could be very beneficial for the Parkinson’s community.
As many people within the Parkinson’s community will be aware, 2017 represented the 200th anniversary of the first report of Parkinson’s disease by James Parkinson.
It also the 20th anniversary of the discovery of first genetic mutation (or variant) that increases the risk of developing Parkinson’s. That genetic variation occurs in a region of DNA (a gene) called ‘alpha synuclein’. Yes, that same alpha synuclein that seems to play such a critical role in Parkinson’s (Click here to read more about the 20th anniversary).
In 2018, we will be observing the 20th anniversary of the second genetic variation associated with Parkinson.
That gene is called PARKIN:
Title: Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism.
Authors: Kitada T, Asakawa S, Hattori N, Matsumine H, Yamamura Y, Minoshima S, Yokochi M, Mizuno Y, Shimizu N
Journal: Nature. 1998 Apr 9; 392(6676):605-8
In 1998, Japanese researchers published this report based on 5 individuals from 4 Japanese families who were affected by juvenile-onset Parkinson’s. In family 1, the affected individual was a female, 43 years old, born of first-cousin parents, and her two younger brothers are healthy. Her condition was diagnosed in her teens and it had then progressed very slowly afterwards. Her response to L-dopa was very positive, but L-dopa-induced dyskinesia were frequent. In family 2-4, affected individuals (born to unrelated parents) exhibited very similar clinical features to the subject in family 1. The age of onset was between 18 to 27 years of age.
Using previous research and various techniques the investigators were able to isolate genetic variations that were shared between the 5 affected individuals. They ultimately narrowed down their search to a section of DNA containing 2,960 base pairs, which encoded a protein of 465 amino acids.
They decided to call that protein PARKIN.
PARKIN Protein. Source: Wikipedia
How much of Parkinson’s is genetic?
Gene therapy involves treating medical conditions at the level of DNA – that is, altering or enhancing the genetic code inside cells to provide therapeutic benefits rather than simply administering drugs. Usually this approach utilises specially engineered viruses to deliver the new DNA to particular cells in the body.
For Parkinson’s, gene therapy techniques have all involved direct injections of these engineered viruses into the brain – a procedure that requires brain surgery. This year, however, we have seen the EXTREMELY rapid development of a non-invasive approach to gene therapy for neurological condition, which could ultimately see viruses being injected in the arm and then travelling up to the brain where they will infect just the desired population of cells.
Last week, however, this approach hit a rather significant obstacle.
In today’s post, we will have a look at this gene therapy technology and review the new research that may slow down efforts to use this approach to help to cure Parkinson’s.
Gene therapy. Source: rdmag
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 begun to see more and more 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.
A good 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 – 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?
Recently a Parkinson’s-associated research report was published that was the first of many to come.
It involves the use of a genetic screening experiment that incorporates new technology called ‘CRISPR’.
There is an absolute tidal wave of CRISPR-related Parkinson’s disease research coming down the pipe towards us, and it is important that the Parkinson’s community understands how this powerful technology works.
In today’s post we will look at what the CRISPR technology is, how it works, what the new research report actually reported, and discuss how this technology can be used to tackle a condition like Parkinson’s.
Me and my mother (and yes, the image is to scale). Source: Openclipart
My mother: Simon, what is all this new ‘crispy’ research for Parkinson’s I heard about on the news?
Me: Huh? (I was not really paying attention to the question. Terrible to ignore one’s mother I know, but what can I say – I am the black sheep of the family)
My mother: Yes, something about ‘crispy’ and Parkinson’s.
Me: Oh! You mean CRISPR. Yeah, it’s really cool stuff.
My mother: Ok, well, can you explain it all to me please, this ‘Crisper’ stuff?
CRISPR.101 (or CRISPR for beginners)
In almost every cell of your body, there is a nucleus.
It is the command centre for the cell – issuing orders and receiving information concerning everything going on inside and around the cell. The nucleus is also a storage bank for the genetic blueprint that provides most of the instructions for making a physical copy of you. Those grand plans are kept bundled up in 23 pairs of chromosomes, which are densely coiled strings of a molecule called Deoxyribonucleic acid (or DNA).
DNA’s place inside the cell. Source: Kids.Britannica
In addition to looking at current Parkinson’s disease research on this website, I like to look at where technological advances are taking us with regards to future therapies.
In July of this year, I wrote about a new class of engineered viruses that could potentially allow us to treat conditions like Parkinson’s disease using a non-invasive, gene therapy approach (Click here to read that post). At the time I considered this technology way off at some point in the distant future. Blue sky research. “Let’s wait and see” – sort of thing.
So imagine my surprise when an Italian research group last weekend published a new research report in which they used this futurist technology to correct a mouse model of Parkinson’s disease. Suddenly the distant future is feeling not so ‘distant’.
In today’s post we will review and discuss the results, and look at what happens next.
Technological progress – looking inside the brain. Source: Digitial Trends
I have said several times in the past that the pace of Parkinson’s disease research at the moment is overwhelming.
So much is happening so quickly that it is quite simply difficult to keep up. Not just here on the blog, but also with regards to the ever increasing number of research articles in the “need to read” pile on my desk. It’s mad. It’s crazy. Just as I manage to digest something new from one area of research, two or three other publications pop up in different areas.
But it is the shear speed with which things are moving now in the field of Parkinson’s research that is really mind boggling!
Take for example the case of Squalamine.
In February of this year, researchers published an article outlining how a drug derived from the spiny dogfish could completely suppress the toxic effect of the Parkinson’s associated protein Alpha Synuclein (Click here to read that post).
The humble dogfish. Source: Discovery
And then in May (JUST 3 MONTHS LATER!!!), a biotech company called Enterin Inc. announced that they had just enrolled their first patient in the RASMET study: a Phase 1/2a randomised, controlled, multi-center clinical study evaluating a synthetic version of squalamine (called MSI-1436) in people with Parkinson’s disease. The study will enrol 50 patients over a 9-to-12-month period (Click here for the press release).
Wow! That is fast.
Yeah, I thought so too, but then this last weekend a group in Italy published new research that completely changed my ideas on the meaning of the word ‘fast’. Regular readers will recall that in July I discussed amazing new technology that may one day allow us to inject a virus into a person’s arm and then that virus will make it’s way up to the brain and only infect the cells that we want to have a treatment delivered to. This represents non-invasive (as no surgery is required), gene therapy (correcting a medical condition with the delivery of DNA rather than medication). This new study used the same virus we discussed in July.
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: