Interview conducted by April Cashin-Garbutt, BA Hons (Cantab)
Please can you give a brief introduction to lymphopenia?
Lymphopenia is when you lack the T cells of your immune system. T cells are very important for controlling infection. Probably the most known cause of lymphopenia is HIV. Human immunodeficiency virus attacks and kills T cells. In most patients, T cells are restored when you treat them with antiretroviral treatment for HIV, but in some patients they are not.
There are also a number of other conditions that can cause lymphopenia. For example, it can occur after bone marrow transplant and also with certain cancers. There is also a condition called idiopathic lymphopenia where patients suffer from a lack of T cells for an unknown reason.
Lymphopenia leaves you open to a variety of more or less serious consequences.
Are there different levels of lymphopenia?
There are certainly different levels or severities. You’re commonly held to have a healthy T cell immune system if you have more than 500 CD4 T cells, which are one of the main types of T cells.
Your risk of infections, and other illness and morbidities, increases fairly proportionally as you have less and less of these T cells. If you are below 100 you are severely lymphopenic and at high risk of many things including the main indication that we are going after which is Progressive multifocal leukoencephalopathy (PML).
What are the main causes of lymphopenia?
The main cause is HIV. But lymphopenia can also be caused by cancers themselves. It can be caused by drug treatments for cancer and also some other drug treatments as well.
Lymphopenia can also be caused by the treatments needed in preparation for bone marrow transplant, because they are ablative, i.e. they suppress the immune system purposefully in that case. Not everyone recovers from this immunosuppression and they remain lymphopenic.
There is also the idiopathic class, which is lymphopenia of unknown origin.
What types of diseases are driven by lymphopenia?
Depending on how severe your lymphopenia is, or how long lasting it is and other factors that are not fully understood, it causes you to get illness. These can be new viral infections, or reactivation of existing viral infections. These can be very hard to treat. We are talking about viral infections that don’t necessarily have effective treatments or any treatments at all.
There is a virus called the John Cunningham (JC) virus, which is actually endemic in the population: so you’ve probably got it, I’ve probably got it and so have many other people. But because we have a fully functioning immune system, the JC virus does not do anything to us. It is kept under control in reservoirs in the body. Essentially, your immune system keeps it dormant.
In some patients without a fully functioning immune system, the virus can reactivate. When the JC virus reactivates it attacks the Central Nervous System and strips nerves of myelin and causes big lesions and very serious neurological diseases and death.
It is a very rare disease, with around 4000 patients in the EU and the US per year, but it is very severe and there is no existing treatment for it.
Please can you outline Cytheris’ pipeline and products for lymphopenia driven diseases?
We are essentially a mono-product company. Our product is CYT107. It is a recombinant version of the human body’s own growth factor that promotes the production and the life and the function of T cells, which is a factor called interleukin 7. Our product is recombinant glycosylated human interleukin7.
We have now given this product to over 250 patients with different backgrounds and causes of lymphopenia. We have consistently seen a very nice improvement in the quantity and the quality of the T cell immune system.
Why have Cytheris refocused their pipeline to concentrate on orphan diseases and HIV-INR?
Basically because this is where we see, particularly in the orphan disease side, the greatest need and the shortest pathway to market. For any biotech company that is a very important factor.
Along with the fact that bringing treatments for diseases where there are no currently available treatments and the effect of the disease is very severe, is, of course, what both health systems and pharmaceutical companies are looking for. So clearly, it makes very good sense to target there. This is really where we are putting all of our focus now.
We will now only progress what we call the HIV-INR indication (reducing overall risk of illness and death to HIV patients whose HIV is controlled but who remain lymphopenic) with outside support, because it is a much wider and longer development. The medical need is certainly there, but it is not as urgent as for PML and other resistant viral infections that you might get in a lymphopenic situation.
What are Cytheris’ plans for the future?
Recently we have succeeded in obtaining our orphan drug designation for the PML indication in the US.
We have previously got a very similar designation in Europe and we have discussed the design of a single trial to register the product for the treatment of PML with European authorities. We are going to be discussing that design with the FDA before the end of the year.
The intention then is to launch the trial early next year and take the product through to the point where we will be able to register it in 2015 and have it on the market by the end of that year.
Where can readers find more information?
They can visit our website: http://www.cytheris.com
About Damian Marron
Damian Marron, 49, is a highly experienced executive with strong experience in orphan diseases. He was previously CEO of Trophos SA from June 2008. Under his tenure, Trophos spearheaded a major EU funded consortia of leading global experts and specialists working on orphan diseases including Amyotrophic Lateral Sclerosis (ALS). He has also pushed through a Phase III trial for ALS and was instrumental in attracting EUR 34 million in funding. This includes EUR ten million from Actelion Ltd for an exclusive option agreement to purchase Trophos for a price that could have reached up to EUR 195 million.
Damian has extensive experience in the biotechnology and international pharmaceutical industry, including financing, corporate development, product and technology licensing, research and development and sales and marketing.
Prior to Trophos, he was executive vice president corporate development at NicOx SA, where he was responsible for the establishment of major collaborations with Merck and Co. Inc. and Pfizer Inc. and participated in financing rounds raising in excess of EUR 175 million.
Previously, he held various business development and operational roles at 3M Pharmaceuticals, Orphan Europe, Rhone-Poulenc-Rorer and Glaxo.