Professor Marie Scully is a professor of haemostasis and thrombosis at UCL and a Consultant Haematologist working in non-malignant haematology at UCLH. Professor Scully has recently received a grant of around £360,000 grant from LifeArc for a phase 2 study to investigate the impact of COVID-19 on thrombosis and a potential mitigation therapy through plasma exchange.

What changes does COVID-19 cause in the blood and what does this mean for patients?

COVID-19 is a relatively new disorder that we knew very little about. Information that we had from severely affected countries like China and Italy was given to us in real time, and it became quickly evident that patients with severe symptoms showed two main effects: Inflammation, a reactive process, and thrombosis, a clotting process. As my main area of specialisation is in platelet disorders, immune conditions and in particular a very rare condition called thrombotic thrombocytopenic purpura (TTP), by background, in conjunction with our ICU colleagues, we were in a position to undertake and understand both of those two pathways in relation to COVID-19.

We had to spend time looking at all the thrombotic potentials and factors. Initially, it was thought that there were many blood clotting factors affected, however we were able to quickly disprove this internally because of the wealth of patients we had. What we noticed, was that all the blood clotting factors are essentially normal other than it would appear, one of them – von Willebrand factor (VWF), one of the biggest proteins in our body. These were found to be very high, which we would expect in patients who are severely unwell.

One of the specific factors that we look at in our disease area of TTP is something called ADAMTS13, an enzyme which is important in slicing up and controlling von Willebrand factor. This is crucial in ensuring that when we bleed, we have enough von Willebrand factor at the right length with platelets to stem bleeding in our body, but conversely if the VWF levels are very high and you have long types of the protein, it increases thrombotic risks. We were able to demonstrate in patients with severe COVID, that their VWF and ADAMTS13 levels were disproportionate, so that we were getting a very high ratio.

Furthermore, there were other groups that undertook histopathology and they demonstrated in patients who died from severe COVID, there was evidence of small clots in the blood vessels particularly in the lungs. It was thought that is, in conjunction with the increased thrombotic tendency, was highly significant and contributory.

Later, there was also a suggestion that other organs are affected, including the kidneys, brain and heart. It was on the basis of the inflammatory and thrombotic risk in severe COVID-19 patients, that we undertook a feasibility study to see the role of plasma exchange.

What is plasma exchange and what does the process involve?

Plasma exchange is an intervention that we primarily undertake in extremely sick patients. For us, it’s often in TTP, but it is used in many other areas of medicine. Plasma exchange is a procedure using a machine not dissimilar to a dialysis type machine, where the patient’s blood is removed from their body and the plasma, the straw coloured part of the blood, is taken away and the red cells and platelets are put back in. We then replace plasma with that collected from healthy, non-COVID donors. Patients don’t normally become unwell during this procedure as such, as there is no change in the fluid levels. Risks from it are that you can have reaction to the plasma, but this is extremely low risk given the type of plasma we use in the UK – we use specially treated plasma which prevents reactions and is very protective from viruses and other pathogens.

Why have you identified plasma exchange as a suitable therapeutic option to explore for COVID-19?

We undertook a feasibility exercise, to identify in those patients who had very severe lung injury who were on CPAP, or looked like they may need to be put onto a ventilator because their disease was so progressive. We undertook a daily   plasma exchange for 5 days. This involved the removal of a patient’s blood volume.

During this 5 day period, we were able to demonstrate that we could reduce the inflammatory component of COVID-19, which was very important because the inflammation was a continuous process that causes ongoing damage to organ tissue, which requires lessening in order for patients to start to improve. It reduced the thrombotic component of COVID-19 and we were able to bring van Willebrand Factor and ADAMTS 13 levels from very high levels down to normal levels – and that’s only over a five day course.

We also demonstrated that the patient’s respiratory function improved significantly over the five days in comparison to patients that were on intensive care at the time. We were also able to increase the understanding with regards to other organ involvement which was less clear at that time, for our patients that received plasma exchange, all of them had completely steady renal function. In the patients comparably on the intensive care unit that did not have plasma exchange, their renal function deteriorated and some required kidney support via dialysis. Therefore, we were able to show that we were protecting and improving not only the respiratory system, but also other organs, and that was by reducing the inflammatory and thrombotic component of COVID-19 – the effect of the virus hyper stimulating cells.

Please provide an overview of the work you are doing at UCLH for this LifeArc funded project.

The feasibility study was important in demonstrating the benefit of plasma exchange, especially so as plasma exchange is a very expensive and intensive therapy to consider without sufficient data to support its benefit. The data provided from our feasibility study was reviewed by LifeArc, who have supported a phase 2 study.

It is very important, in particularly in a very severe disease like COVID-19, to be able to demonstrate that a therapy is better or comparable in a randomized study to standard of care; we must demonstrate significant efficacy. LifeArc is funding this work through the phase 2 study, where we will investigate the role of plasma exchange compared to not having the treatment, in patients who have severe COVID-19. If we are able to demonstrate benefit of patient outcomes and prevent the need for ventilation and end organ damage, this can be published and replicated by any site in any country.

How will you access appropriate patients for this study?

We are looking at patients with severe COVID-19, which is  a very select group of patients who require hospital admission and organ support, primarily the lungs, which may include intubation and ventilation.

Patients must fulfil a certain level of what we call inclusion criteria, which are parameters they have to meet before we can offer them the opportunity to go into the study. This includes being aged between 18-70 and having specific levels of respiratory function.

The review of patients with COVID-19 that would be appropriate for our clinical trials is undertaken on a daily basis at UCLH, so we can identify in real time patients with COVID-19, the disease severity, and we can monitor that and if they meet the criteria, they will be offered access to this clinical study.

How have UCL TRO supported you in this project?

Initially on the back of the feasibility study, we were put in contact with the Translational Research Office (TRO), which is not an area of UCL that I had been familiar with. It was an absolute pleasure to work with Dr Pamela Tranter (Head, Translational Research Group) from the Translational Research Office, who made sure that the project was documented to cover everybody’s needs including the reviewer’s. The whole process really was very straight forward, in regards to accepting the work we had done and the benefit of the work, to supporting the funding application and liaising with LifeArc to see if they would be interested in funding the phase two study. Given that there was likely to be a phase 2 study to directly impact the UK, the time pressure was acknowledged by all, making the process very quick, both with the TRO and with LifeArc who asked the right questions and reviewed the protocol. It was a very fluid and receptive process, and the response we got with regards to funding the phase 2 was really an exceptional award.

Contact the UCL Translational Research Office

What are the next steps for your work?

Now that the study is open and available nationally to whoever wants to take part, I’m eager to complete the study in a very timely manner. This will of course depend on the number of patients that come through but we are pleased to have now started treating patients.

About Professor Marie Scully

Professor Marie Scully is a Consultant Haematologist at University College London Hospitals (UCLH) and Professor of haemostasis and thrombosis at UCL. Professor Scully’s particular area of interest is acquired haemostasis and platelet disorders, specifically Immune Thrombocytopenic Purpura (ITP).

Professor Scully runs specialist ITP and TTP clinics and works on obstetric haematology, as part of a team that specialises in treating varied and complex thrombosis, acquired and inherited bleeding disorders.

In the next interview as part of the Early Career Innovators series, acknowledging the amazing translational work being done by early career researchers within the UCL Therapeutic Innovation Networks, Dr Athina Dritsoula and Dr Carlotta Camilli highlight their joint Biologics TIN Pilot Data Fund awarded project focusing on the effect of LRG1 blockade in pancreatic cancer.

How did this joint project come about?

CC: Athina and I both arrived at the Institute of Ophthalmology to do our post-docs where, weirdly enough, we don’t do eye-related research but explore vessel behaviour using ex-vivo models of angiogenesis and in vivo models of solid tumours.

What is the title of your project and what does it involve?

AD: The interest of our lab is focused on the LRG1 protein, which is involved in pathological angiogenesis, but we don’t know much about its normal function. Based on our research, we believe that blocking the function of the LRG1 protein by using a specific monoclonal antibody that we have developed in the lab will be beneficial in conditions with abnormal angiogenesis like cancer. In fact, LRG1 is upregulated in pancreatic cancer, which is a type of cancer with minimal survival that remains untreated. So, Carlotta and I designed this project to study the effect of LRG1 blockade in pancreatic cancer.

What is the motivation behind your project/therapeutic?

CC: Pancreatic cancer is a leading cause of deaths from cancer that kills about half a million people worldwide each year. The current standard of care involves combination cytotoxic chemotherapy, which often fails due to the complex tumour microenvironment. So, there is a great need for developing novel therapeutic strategies that will target new molecules and pathways, and we believe that our anti-LRG1 antibody could be a great novel therapeutic candidate.

Why did you want to apply to the Biologics TIN Pilot Data Fund?

AD: We both thought that the Biologics TIN Programme is a great opportunity to get enough funding to support a short 6-month project that would allow us to a) test our hypothesis and b) generate pilot data to design a bigger project in future if (a) proves right.

Join the Biologics TIN

What do you hope to achieve in the 6 months duration of your project?

CC: Well, we hope that we will manage to prove that our hypothesis is correct, and COVID-19 situation allowing, generate data to apply for more funding and get this project further. Our -very ambitious – aim is to get our antibody into clinical trials for pancreatic cancer in a few years’ time!

What are your next steps from now?

AD: Hope that our orders will be delivered on time and that our experiments will work as planned! We need to complete the project before a second lock down crushes.

Do you have any top-tips for applicants currently going through the application process for the other TIN Pilot Data Funds?

AD: The 10 minutes Dragons’ Den round felt much longer than it was! Be well prepared for all types of questions, and maybe have a mock interview with your PI, if possible.

CC: Spend enough time to prepare the slide presentation. It might seem easy but it’s not, as it needs to be very concise and straight forward!

About Dr Athina Dritsoula

Dr Dritsoula studied an undergraduate degree in Molecular Biology and Genetics in Greece over a decade ago before arriving in the UK for a Master’s and PhD, and UCL has been home to Dr Dritsoula since. Although human genetics was Dr Dritsoula’s first love, Dr Dritsoula quickly found her “forte” in vascular biology – studying the biology of big human vessels during a PhD, and then smaller vessels stability and angiogenesis during post-doc.

About Dr Carlotta Camilli

After completing a Master’s in Medical Biotechnology, Dr Camilli left Italy to start a PhD at UCL focusing on the use of vascular progenitors for the development of a bioengineered muscle.

However, Dr Camilli’s broad interest in translational medicine pushed her to explore a different pathological context during post-doc, namely the tumour angiogenesis. Dr Camilli found jumping on this new field a difficult but exciting challenge!

In the second interview as part of the new Early Career Innovators series, acknowledging the amazing translational work being done by early career researchers within the UCL Therapeutic Innovation Networks, Dr Anais Cassaignau highlights her Biologics TIN Pilot Data Fund awarded project “Developing an scFv binder against nascent huntingtin” and presents some advice for future applicants.

Please provide an overview of your Biologics project.

This project entitled “Developing an scFv binder against nascent huntingtin” is looking to exploit the unique features of nascent proteins, i.e. the shapes they form while they are being made. I am currently pursuing the novel disease angle that is the focus of this award.

Relative to the fully formed protein, the nascent protein is typically protected against misfolding /aggregation. We are looking to show that this entity may be a tractable therapeutic target in Huntington’s Disease.

What is the motivation behind your project/therapeutic?

I am interested in understanding how proteins fold while they are being synthesised by the ribosome, and how the ribosome itself regulates and modulates this process¹. The correct folding of proteins in the cell is vital to all forms of life, and scientists are increasingly recognising that many diseases bear protein misfolding hallmarks including devastating neurodegenerative illnesses, several cancers and also diabetes.

Huntington’s is a devastating neurodegenerative disease, designated as an incurable disease with only symptomatic treatment currently available, and which often involves invasive delivery e.g. via spinal chord injections.  This is despite seminal work in the field that underpins much of what we understand regarding the pathological underlying processes and in particular how the causative agent, huntingtin, forms aggregates. I hope to be part of devising new therapeutic strategies that involve targeting the mutant form of huntingtin at the earliest point of biosynthesis – an angle which has not previously been explored in this manner.

Why did you want to apply to the Biologics TIN Pilot Data Fund?

I wanted to initiate a crucially needed orthogonal extension to the research I have been undertaking; building upon the wealth of collective knowledge that the entire lab and myself have been building together over years about how proteins are made and how they fold, and applying these paradigms to develop relevant disease-related models.

What do you hope to achieve in the 6 months duration of your project?

I want to demonstrate that targeting a nascent protein is possible, through binding an antibody and scFv to a nascent huntingtin during biosynthesis and monitoring how this modulates the folding/misfolding outcomes for this protein.

What are your next steps from now?

Finessing of assays and the production of samples of the nascent huntingtin. The protein will be translationally-arrested (a “snapshot” of biosynthesis) and then we will test the interaction of our antibody and scFv to it, and see how this influences the fate of this aggregation-prone protein.

Do you have any top-tips for applicants currently going through the application process for the other TIN Pilot Data Funds?

I would strongly encourage prospective applicants to reach out to the members of their respective TIN as the first step; their expertise will help you to appropriately refine your initial ideas and define the key questions in order to apply. Finally… Make a list of all the things you don’t know and read about them one by one.

Join the UCL Therapeutic Innovation Networks

About Dr Anais Cassaignau

Dr Cassaignau became interested in protein folding on the ribosome during her final year of BSc Biochemistry at UCL. Following this, Dr Cassaignau initiated a project within the Research department of Structural and Molecular Biology and has not left since, undertaking a Wellcome Trust-funded PhD and postdoc with John Christodoulou.

1. How does the ribosome fold the proteome? Cassaignau, AME, et al Ann. Rev. Biochem, 2020, 89, 389-415.  https://www.annualreviews.org/doi/abs/10.1146/annurev-biochem-062917-012226 

Dr Ahad Rahim is an Associate Professor of Translational Neuroscience and Associate Director of Research at the UCL School of Pharmacy. Dr Rahim’s group works on the development of novel therapies for neurodegenerative diseases and recently at the end of 2019, received an MRC DPFS grant of £654,904 to develop gene therapy for infantile neuroaxonal dystrophy (INAD).

Please provide an overview of infantile neuroaxonal dystrophy (INAD) and the need to develop a new therapy.

INAD is a devastating inherited neurodegenerative condition that affects children. It’s caused by mutations in a gene called PLA2G6 that encodes for an enzyme known as Phospholipase A2, which leads to neurodegeneration in the nervous system of patients accompanied by an inflammatory response. The downstream effect of that is cognitive decline and progressive motor disorder, which leads to death in the first decade of life.

The symptoms usually present between 6 months and 3 years of age, and patients are completely dependent on family, carers and the healthcare system for the duration of their lives. This, of course, has a very significant emotional and social burden.

Palliative care is currently the only way to respond to INAD, with there being no clinical treatment available for the condition. Therefore, there’s an overwhelming need to develop a new and effective therapy for INAD.

We work closely with Professor Manju Kurian at the UCL Great Ormond Street (GOS) Institute of Child Health and she is the clinical lead for patients with this disease. She sees patients living with the condition and is invaluable to our work. Professor Kurian and I have been working together for the last 4/5 years to provide proof of concept studies supportive of gene therapy for INAD.

Why have you identified gene therapy as a good treatment potential for INAD?

The theory of gene therapy has been around for quite a while but has taken almost a generation for it to develop into something that is clinical viable. UCL now proudly has many success stories of gene therapy clinical trials leading to spinout companies.

Visit the UCL Therapeutic Innovation Networks (UCL TINs) website for more gene therapy case studies.

So overall, we have a very good track record of gene therapy at UCL.

Gene therapy is revolutionising the way that we think about treating genetic diseases and although it has taken a while to get to this point, there have been some really pioneering clinical trials in neurological diseases similar to INAD. One example is spinal muscular atrophy where gene therapy has had life-saving effects. This success story in a neurological condition with gene therapy, have led us to investigate the use of gene therapy for other neurological diseases – INAD being one of them. We know which gene is defective in INAD, so we can investigate the use of gene therapy to deliver a healthy version of that gene to compensate for the defective version. We do this in the hope that this would cure the patient.

Therefore the three overwhelming considerations that make us think that INAD is a good candidate for gene therapy are: we know what the effected gene is, there is no other option available to the patient, and gene therapy has had a good effect in another genetic neurological condition.

What is AAV-mediated gene therapy?

Adeno-associated viruses (AAV) occur naturally; we have all been infected with AAV at some point and since they are non-pathogenic, you won’t even know you have it. AAV-mediated therapy involves delivering a gene for therapeutic purposes using a modified and safe AAV virus.

Getting genes into cells is not an easy task because our cells are designed with defensive mechanisms in place to prevent exogenous DNA from coming in and corrupting its own DNA. Therefore to be able to get your therapeutic gene into the right part of the cell that you want to correct, you need a vehicle or mechanism for it to get in – that’s where we use viruses like AAV.

Viruses are at the top of the food chain in terms of being able to deliver their genetic material into a cell. In order to exploit this ability for gene therapy, we take viruses like AAV, remove the bits which are potentially harmful, toxic or we don’t need, and we replace that with therapeutic genetic material – in the instance of INAD, it’s the PLA2G6 gene. We then use the virus as a trojan horse, as it now carries our therapeutic gene and delivers it into the cell effectively.

How will you optimise AAV9-mediated gene therapy for INAD as part of this DPFS project?

In mouse models, we have been able to show that AAV-9 gene therapy is effective by rescuing the mouse from premature death and reducing the loss of neurons in the brain. However, as always, there’s room for improvement in the vector. It is important to remember that due to size differences between a mouse brain and human brain, what you do in a mouse, is very different to what you do in a human being. What we want to do is give ourselves the best chance of therapeutic effect in that much bigger brain – and that is a challenge.

In this grant, we want to modify the AAV vector by improving elements of it. This includes the optimising how the gene is expressed once it’s delivered into the cell. We’re also looking at the best way of administering this AAV9 vector via different routes of administration to give the best coverage in a larger brain.

Can you describe the results from your proof-of-concept data that demonstrates therapeutic efficacy of this approach?

Over the past 4 years we’ve been working on a mouse model that has a mutation in the PLA2G6 gene. The model has very similar symptoms, levels of neurodegeneration and inflammatory response in the brain as human INAD patients do. This is important because what we don’t want to do, is study a mouse model that is not faithful to what happens in human beings. We have been able to confirm that that is a good model to be able to test future novel therapy on.

We then designed an AAV9 vector which carried the therapeutic human PLA2G6 gene and we administered this into the PLA2G6 deficient mice. We looked to see if there was an improvement in lifespan, locomotor function, behaviour and neuropathology.

We were pleased to find a significant improvement in all of the markers of therapeutic efficacy that we were looking for which showed benefit from the AAV9 gene therapy. That’s quite promising in such an aggressive model of neurodegeneration.

It was on the basis of that preliminary data that we applied to the MRC asking for funding to be able to take this further towards the clinic. If we make the AAV9 vector better, can we administer it in a way that is more efficacious and would be most beneficial one day in human beings?

What stage are you up to with your work?

Now that we have shown proof-of-concept in our work, we want to make further improvements on survival, locomotor function and neuropathology in the mice so that we develop the very best therapy in human beings and we know that there is room for improvement in the vector to achieve this.

The two year grant will allow us to do more preclinical studies – including large animal studies which will help give us a lot of information as to how it will work one day in humans.

Can you highlight any barriers to translation you have come across?

In the gene therapy community there are certain hurdles which exist as potential bottlenecks. As gene therapy is growing very quickly and is a massively expanding field, the availability of facilities to manufacture vectors for clinical use, is relatively few in number. They aren’t many places that can take a viral vector and produce it at the quantity, quality and purity that would be suitable to go into human beings.

If you think about the amount of gene therapy activity happening around the world – it’s a huge burden on those facilities, meaning that stakeholders are having to wait an extremely long time to get the vector manufactured at an acceptable grade which they can then use to run a clinical trial.

There needs to be more of these facilities and more people trained in gene therapy technology. I would say that we as academics, need to be training more people in gene therapy technology to provide the workforce for a field that is growing so quickly.

Another consideration is the business side of gene therapy. Sometimes there are patents on certain vectors or parts of a vector. This is a commercial necessity and you may need a license to use that particular technology. This is not a problem in itself, but is something else that we have to think ahead of when working in such a rapidly expanding field.

When you write MRC DPFS applications, there are very specific questions in the application around freedom to operate which UCLB were able to help us answer, including “What is the current IP issues around this?”, and “Do you foresee any problems in the future in terms of getting access commercially to these technologies?”. These are important questions to ask because the MRC want to be sure that whatever we are developing has a commercial exit strategy. It would be tragic if we develop a promising treatment but don’t have commercially viable routes to take it forward and get it to the number of patients that need it.

How has the UCL Translational Research Office (TRO) supported you in your work?

The TRO have helped a lot in many translational projects that have come out of my lab. I’ve worked with Translational Research Manager Dr Alethea Cope right from the beginning for every one of my projects, and she has been instrumental. Alethea has recently moved on from the TRO but I am fortunate to now have support from Dr Simon Eaglestone (UCL TRO Translational Research Manager) who has managed other gene therapy projects at GOS, which are now progressing to clinical trial.

These projects are often complex in the way that they are designed and lot of things that we’re doing are the first time anyone has tried them. Within our projects, it is a common need to contract out some of the work to contract research organisations (CRO’s) external to UCL.  This process requires a lot of time invested in terms of engaging with those CROs, making them understand what work we want to do, and getting quotes from them on very specialised/tailored work. Where the TRO have been really instrumental, is connecting me with the right CROs and allowing me to have that conversation with them.

The TRO are also very up to date and knowledgeable about what’s happening in general in the gene therapy field. They often know things that we don’t and so they are able to guide us in the right direction. For example, in the manufacturing of the clinical grade gene therapy vectors, the TRO know which facilities are perhaps in the best position to help us. Those nuggets of information are critical and are invaluable in helping us to succeed.

What are the next steps for this project?

Once this grant has ended, it will allow us to have more detailed conversations with the clinical community and with regulators who will assess our work and determine whether it’s safe for potential clinical translation. The link between my lab and clinicians like Professor Kurian is really important, and it will allow us to move along a well thought-out translational pathway and get this treatment to patients who badly need it.

About Dr Ahad Rahim

Dr Ahad Rahim is an Associate Professor in Translational Neuroscience and leads a research team at the UCL School of Pharmacy focussed on studying lethal or debilitating neurodegenerative disorders to evaluate disease mechanisms and develop novel therapies.

His team are involved in the pre-clinical testing of therapeutic modalities including gene and stem cell therapies, exosomes and small molecule neuroprotective drugs. Diseases and conditions being studied in Dr Rahim’s laboratory include Niemann-Pick disease type C, Gaucher disease, PLA2G6-associated infantile neuroaxonal dystrophy (INAD), Batten disease (CLN2, CLN3, CLN5, CLN6 and CLN7), Parkinson’s disease, neonatal hypoxic-ischemic encephalopathy and peripheral nerve damage.