According to the European Organisation for Rare Disease, there are 20–30 million people in Europe alone who are affected by one of an estimated 6,000 rare diseases.
These include many rare genetic disorders, such as Duchenne’s muscular dystrophy, but also rare forms of cancer and auto-immune disease. The term rare can, therefore, be misleading as many diseases are entering this definition.
Rare disease is still considered a ‘Blue Ocean’ for biotech, so we decided to list a few of the diseases we’ve encountered – and who in Biotech we’ve found to be working on them.
This is not a comprehensive list (for sure), but just an example of some of the range of disease types and potential therapeutics out there.
Phenylketonuria (PKU) is a rare genetically conferred metabolic disease, where the amino acid phenylanaline (PHE) is not broken down properly. This leads to high PHE levels and causes a wide range of psychological symptoms, which patients need to manage with life-long controls on their diet.
Merck (Germany) opted to return its PKU candidates Kuvan and Peg-Pal back to BioMarin (US) from January 2016, which was a bit of a blow for patients.
However, Erytech (France) is still working on a drug-transportation system using red blood cells. US Rubius Therapeutics joined Erytech on this new approach to drug delivery to work on PKU, backed by the huge VC in the States; Flagship Ventures.
Fragile X Syndrome (FXS) is associated with an array of intellectual and emotional disabilities, and is, in fact, the most common inherited form of mental impairment and Autism Spectrum Disorder. Linked to a genetic mutation of the X Chromosome, the disease is caused by a decreased or absent level of fragile X mental retardation protein.
In October, Woodford Capital trust (the biggest VC in the UK) injected €25M into AMO Pharma for their pre-clinical ras-extracellular signal-regulated kinase pathway (Ras-ERK) inhibitor. This showed potential therapeutic benefits in mice, and plans for this therapy’s phase I/IIa trial were set for Q1 2016 (though clarity on their plans is needed).
Confluenc, on the other hand,d is an American biopharma focused on treatments for Fragile X Syndrome and Autism Spectrum Disorders, after Orphan Designation for both Europe and the US. Its lead product is partnered on with AOP Pharma (Austria).
Sanfilippo A Syndrome (also known as MPS-III) is a metabolic disease which affects fewer than 200,000 children in the US. A genetic mutation of a particular enzyme causes a toxic build up of heparin sulphates, which cause permanent tissue damage and paralysis. Read more on the National MPS Society website.
We interviewed the CEO of Lysogene (France) earlier this year, on her incredible journey to found this clinical stage Gene therapy biotech after her daughter, Ornella, was diagnosed with the syndrome (which has a median survival age of just 13…). Lysogene has since been given a ‘Priority Review Voucher’ (to be redeemed at a later date from the FDA) for their AAV Gene therapy.
UniQure (Netherlands) is also working on a gene therapy for type B of the syndrome, having been granted fast-track for phase III trials in collaboration with France’s Institut Pasteur in September.
Familial Primary HypoAlphalipoproteinemia (FPHA) is a rare syndrome characterized by the absence of or a severe deficiency of ‘good cholesterol’ in circulation. Due to either the impaired production/maturation or the premature destruction of HDL particles and the Reverse Lipid Transport (RLT) pathway, patients experience a rapid accumulation of bad cholesterol (being unable to clear it).
This build up in blood vessels often results in accelerated atherosclerosis (narrowing of arteries) and premature cardiovascular disease.
Cerenis Therapeutics (France) has a phase II drug CER-001 (an engineered human apoA-I-containing pre-beta HDL mimetic) which was granted Orphan Drug Designations from the EMA for cardiovascular diseases like FPHA.
Adult T-cell Leukemia/Lymphoma (ATL/L) is a super rare blood cancer of only a certain type of white cells – T-cells which have been infected by the Human T-Cell Lymphotropic Virus type 1 (HTLV-1). Approximately 5% of all patients infected with HTLV-1 will develop ATL/L, in their lifetime.
Patients are confronted with a lack of well-tolerated and/or performant treatment options which (to-date) include biological treatments with serious adverse reactions. There are also aggressive chemo and antiviral therapies or (when eligible) haematopoietic stem cell transplantations, but these can be time-consuming and uncertain.
Theravectys (France) has an experimental treatment composed of two lentiviral vectors (THV02) to be used in a prime/boost regimen in ATL/L patients infected by the HTLV-1 virus, for which it has Orphan drug designation.
Thrombocytopenic purpura (TTP) is an ultra-rare blood disorder which involves defective von-Willebrand factors (ultra-large vWF) in the hemostatis clotting cascade. This creates a severely low platelet count (thrombocytopenia) with symptoms of anaemia and risk of microthrombi forming within peripheral vessels (and therefore ischemic tissue damage). You can read more in this awesome explanatory blog.
Around 10% of cases are congenital, with the majority being acquired through an autoimmune response to the vWF cleavage enzyme ADAMTS13. Caplacizumab is an antibody from Ablynx (Belgium) which was given Orphan Drug designation by the EMA and FDA (in 2009), as the first therapy for the congenital and acquired types of TTP.
On the other hand, Suppremol (Germany), was acquired by Baxalta last year. It’s lead candidate SM101 is an investigational immunoregulator that has completed phase IIa studies in idiopathic TTP.
Mastocytosis is a rare disorder characterized by the abnormal accumulation of mast cells (cell types normally involved in healing and allergy and anaphylaxis) in the skin, bone marrow, and internal organs (liver, spleen, gastrointestinal tract and lymph nodes). You can read more on the symptoms and development of Mastocytosis by the National Organisation of Rare Diseases.
AB Science (France) has a propietary a tyrosine kinase inhibitor (Masitinib) which has already been registered for veterinary medicine in Europe and in the US. This human phase III trial enrolled 134 patients with severe systemic mastocytosis, results for which were published in December.
Who else is working on these diseases? And do you feel that Biotech is still as comprehensively invested in Orphan drug indications as it once was…?
Feature Image Credit: Remix of Graphics by Labiotech (Source: Rare Disease Day)