Recent analysis of blood samples collected during the Phase II clinical trial of Exenatide in Parkinson’s has uncovered a very interesting finding that could have major implications for not only Parkinson’s, but for many different neurological conditions.
Exenatide is a treatment that helps to control glucose levels in people with diabetes. More recently, however, it has been suggested that this drug may also have beneficial effects in Parkinson’s. A collection of clinical trials in Parkinson’s are currently unway to test this idea.
The researchers who conducted a Phase II clinical trial of Exenatide in Parkinson’s have analysed ‘exosomes‘ collected from the blood of participants, and they found something rather remarkable.
In today’s post we will discuss what exosomes are, what the researchers found, and why their discovery could have major implications for all of neurological research.
This week, however, researchers involved in the study reported yet another really interesting finding from the trial. And this one could have profound consequences for how we study not only Parkinson’s, but many other neurological conditions.
What did they find?
Last week this report was published:
Title: Utility of Neuronal-Derived Exosomes to Examine Molecular Mechanisms That Affect Motor Function in Patients With Parkinson Disease: A Secondary Analysis of the Exenatide-PD Trial.
Authors: Athauda D, Gulyani S, Karnati H, Li Y, Tweedie D, Mustapic M, Chawla S, Chowdhury K, Skene SS, Greig NH, Kapogiannis D, Foltynie T.
Journal: JAMA Neurol. 2019 Jan 14. doi: 10.1001/jamaneurol.2018.4304. [Epub ahead of print]
In the Exenatide Phase II clinical trial, 60 people with moderate Parkinson’s were randomly assigned to receive either 2mg of Exenatide or placebo once weekly for 48 weeks followed by a 12-week washout (no treatment) period. The results suggested a stablisation of motor features over the 48 weeks of the study in the treated group (while the condition in the placebo group continued to progress).
During the study (which was conducted between June 2014 – June 2016), blood samples were collected at each assessement.
From those blood samples, serum was collected and analysed.
Remind me again, what is serum?
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?
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
The title of today’s post is written in jest – my job as a researcher scientist is to find a cure for Parkinson’s disease…which will ultimately make my job redundant! But all joking aside, today was a REALLY good day for the Parkinson’s community.
Last night (3rd August) at 23:30, a research report outlining the results of the Exenatide Phase II clinical trial for Parkinson’s disease was published on the Lancet website.
And the results of the study are good:while the motor symptoms of Parkinson’s disease subject taking the placebo drug proceeded to get worse over the study, the Exenatide treated individuals did not.
The study represents an important step forward for Parkinson’s disease research. In today’s post we will discuss what Exenatide is, what the results of the trial actually say, and where things go from here.
Last night, the results of the Phase II clinical trial of Exenatide in Parkinson’s disease were published on the Lancet website. In the study, 62 people with Parkinson’s disease (average time since diagnosis was approximately 6 years) were randomly assigned to one of two groups, Exenatide or placebo (32 and 30 people, respectively). The participants were given their treatment once per week for 48 weeks (in addition to their usual medication) and then followed for another 12-weeks without Exenatide (or placebo) in what is called a ‘washout period’. Neither the participants nor the researchers knew who was receiving which treatment.
At the trial was completed (60 weeks post baseline), the off-medication motor scores (as measured by MDS-UPDRS) had improved by 1·0 points in the Exenatide group and worsened by 2·1 points in the placebo group, providing a statistically significant result (p=0·0318). As you can see in the graph below, placebo group increased their UPDRS motor score over time (indicating a worsening of motor symptoms), while Exenatide group (the blue bar) demonstrated improvements (or a lowering of motor score).
Reduction in motor scores in Exenatide group. Source: Lancet
This is a tremendous result for Prof Thomas Foltynie and his team at University College London Institute of Neurology, and for the Michael J Fox Foundation for Parkinson’s Research who funded the trial. Not only do the results lay down the foundations for a novel range of future treatments for Parkinson’s disease, but they also validate the repurposing of clinically available drug for this condition.
In this post we will review what we know thus far. And to do that, let’s start at the very beginning with the obvious question:
So what is Exenatide?
In October 2015, researchers from Georgetown University announced the results of a small clinical trial that got the Parkinson’s community very excited. The study involved a cancer drug called Nilotinib, and the results were rather spectacular.
What happened next, however, was a bizarre sequence of disagreements over exactly what should happen next and who should be taking the drug forward. This caused delays to subsequent clinical trials and confusion for the entire Parkinson’s community who were so keenly awaiting fresh news about the drug.
Earlier this year, Georgetown University announced their own follow up phase II clinical trial and this week a second phase II clinical trial funded by a group led by the Michael J Fox foundation was initiated.
In todays post we will look at what Nilotinib is, how it apparently works for Parkinson’s disease, what is planned with the new trial, and how it differs from the ongoing Georgetown Phase II trial.
The FDA. Source: Vaporb2b
This week the U.S. Food and Drug Administration (FDA) has given approval for a multi-centre, double-blind, randomised, placebo-controlled Phase IIa clinical trial to be conducted, testing the safety and tolerability of Nilotinib (Tasigna) in Parkinson’s disease.
This is exciting and welcomed news.
What is Nilotinib?
Nilotinib (pronounced ‘nil-ot-in-ib’ and also known by its brand name Tasigna) is a small-molecule tyrosine kinase inhibitor, that has been approved for the treatment of imatinib-resistant chronic myelogenous leukemia (CML).
What does any that mean?
Basically, it is the drug that is used to treat a type of blood cancer (leukemia) when the other drugs have failed. It was approved for treating this cancer by the FDA in 2007.
Big news today from Georgetown University with the announcement that they will be starting a phase II trial for the cancer drug Nilotinib.
Click here to read the press release.
In this post we will discuss what has happened thus far and what the new trial will involve.
Georgetown University (Washington DC). Source: Wallpapercave
In October 2015, researchers from Georgetown University announced the results of a small clinical trial at the Society for Neuroscience conference in Chicago.
It is no understatement to say that the results of that study got the Parkinson’s community very excited.
The study (see the abstract here) was a small clinical trial (12 subjects; 6 month study) that was aiming to determine the safety and efficacy of a cancer drug, Nilotinib (Tasigna® by Novartis), in advanced Parkinson’s Disease and Lewy body dementia patients. In addition to checking the safety of the drug, the researchers also tested cognition, motor skills and non-motor function in these patients and found 10 of the 12 patients reported meaningful clinical improvements.
In their presentation at the conference in Chicago, the investigators reported that one individual who had been confined to a wheelchair was able to walk again; while three others who could not talk before the study began were able to hold conversations. They suggested that participants who were still in the early stages of the disease responded best, as did those who had been diagnosed with Lewy body dementia.
The study involved the cancer drug Nilotinib.
What is Nilotinib?
Nilotinib (pronounced ‘nil-ot-in-ib’ and also known by its brand name Tasigna) is a small-molecule tyrosine kinase inhibitor, that has been approved for the treatment of imatinib-resistant chronic myelogenous leukemia (CML). That is to say, it is a drug that can be used to treat a type of leukemia when the other drugs have failed. It was approved for this treating cancer by the FDA in 2007.
How does Nilotinib work?
The researchers behind the study suggest that Nilotinib works by turning on autophagy – the “garbage disposal machinery” inside each neuron. Autophagy is a process that clears waste and toxic proteins from inside cells, preventing them from accumulating and possibly causing the death of the cell.
The process of autophagy. Source: Wormbook
Waste material inside a cell is collected in membranes that form sacs (called vesicles). These vesicles then bind to another sac (called a lysosome) which contains enzymes that will breakdown and degrade the waste material.
The investigators believe that nilotinib may be helping in Parkinson’s disease, by clearing away the waste building up in cells – allowing the remaining cells to function more efficiently.
This is great, so what happened in 2016?
That’s a great question.
First, the results of the study being published (Click here to read those results). Second, the U.S. Food and Drug Administration (FDA) reviewed Georgetown’s investigational new drug application (IND) for nilotinib in Parkinson’s disease, and they informed the Georgetown University investigators that a new clinical trial could proceed.
But after that, there were whispers of issues and problems behind the scenes.
Back in August we wrote a post about the Phase II trial being delayed due to disagreements about the design of the study (Read that post by clicking here). Two separate research groups emerged from those disagreements (Georgetown University researchers themselves and a consortium including the Michael J Fox Foundation). Click here for the STAT website article outlining the background of the issues, and click here for the Michael J Fox Foundation statement regarding the situation. The Georgetown University team have a lot of leverage in this situation as they control the patent side of things (Click here to see the patent).
We are not sure what has happened since August, but the Georgetown University team has now announced that they are going to go ahead with a phase II trial to look at safety and efficacy of nilotinib in Parkinson’s disease.
What do we know about the new trial?
At the moment the details are basic:
The design of the study involves two parts:
In the first part of the study, one third of the participants receiving a low dose (150mg) of nilotinib, another third receiving a higher dose (300mg) of nilotinib and the final third will receive a placebo drug (a drug that has no bioactive effect to act as a control against the other two groups). The outcomes will be assessed clinically at six and 12 months by investigators who are blind to the treatment of each subject. These results will be compared to clinical assessments made at the start of the trial. (We are not sure if brain imaging – for example, a DATscan – will be included in the assessment, but it would be useful)
In the second part of the study, there will be a one-year open-label extension trial, in which all participants will be randomized given either the low dose (150mg) or high dose (300mg) of nilotinib. This extension is planned to start upon the completion of the first part (the placebo-controlled trial) to evaluate nilotinib’s long-term effects. (We are a little confused by this study design with regards to efficacy, but determining the safety issues of using nilotinib long term is important to establish).
We are not clear on how many subjects will be involved in the study or what the criteria for eligibility will be. All we can suggest is that if you are interested in finding out more about this new study, you can sign up here to receive more information as it becomes available.
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Summing up, this is welcomed news for the Parkinson’s community as we will finally be able to determine if nilotinib is having positive effects in Parkinson’s disease. There have been some concerns raised that the effects of the drug in the first clinical study may have been the result of removing additional Parkinsonian treatments during the study (Click here for more on this). This new study will hopefully help to clarify things.
And fingers crossed provide us with a useful new treatment for Parkinson’s disease.
The banner for today’s post was sourced from William-Jon