ALS, also called Lou Gehrig’s disease, is a rapidly progressive and invariably fatal neurological disease. It attacks neurons responsible for controlling voluntary muscles. ALS results in muscle weakness, progressive disability and eventually death, typically from respiratory failure. Time from onset to mortality is typically short in the range of two to five years. However, ALS is a distinctly heterogeneous disease and the clinical course is variable, with some patients dying within one year from symptom onset and other living for more than a decade.
Muscle weakness results from progressive degeneration of motor neurons in different parts of the central nervous system, where upper and lower neurons selectively die. The cause of damage to the neurons is unknown, but several theories have been proposed, including glutamate toxicity, protein misfolding and oxidative stress.
Prevalence for ALS
The CDC (Centers for Disease Control and Prevention) estimates that there are approximately 16,000 prevalent cases of ALS in the United States and that approximately 5,000 new cases are diagnosed each year. The number of total cases for the largest five markets in the EU (Germany, France, Italy, Spain and the United Kingdom) is estimated to be slightly higher and for the broader European geography the estimate is approximately 40,000 prevalent cases. Hence, the conservatively estimated market for the United States and Europe is approximately 50,000 cases. In addition, Japan is a large market for ALS and is estimated to be between 8,000 and 14,000 cases.
sIBM is an acquired, rare and slowly progressing muscle disorder which becomes apparent during adulthood. Among individuals older than 50 years it is the most common muscle wasting disorder. The disease is generally characterised by progressive weakness and degeneration (atrophy) of the muscles, especially those of the arms and legs, particularly in the quadriceps. sIBM typically affects the ability to grab or manipulate objects, causes trouble walking or rising and can progress to cause severe disability. In addition, difficulty swallowing (dysphagia) due to weakness of throat muscles may occur. sIBM typically presents itself later in life with 87% of patients experiencing onset of symptoms at 50 years of age or more, and earlier symptoms usually only being recognized retrospectively. In most cases, the progression is slow and progresses over the next 10 to 15 years until the affected patient has lost mobility entirely.
Prevalence for sIBM
The size of the patient population in Europe and the United States is not fully elucidated but has been conservatively estimated to be between 7,000 and 15,000 individuals. However, the recent meta-analysis of sIBM prevalence estimates a patient population of approximately 24.8 per million or 17,000 individuals in the United States and the major European countries.
NPC disease is a rare, genetic and progressive disease that impairs the ability of the body to move cholesterol and other fatty substances (lipids) inside the cells. The result is an accumulation of lipids within the body’s tissue, including the brain tissue, causing damage to the affected areas. The symptoms upon onset of NPC vary from fatality during the first months after birth to a progressive disorder not diagnosed until adulthood. The disease affects neurologic and psychiatric functions as well as various internal organs. NPC is usually fatal and the majority of individuals with the disease die before the age of 20. Adults diagnosed with NPC are more likely to present with dementia or psychiatric symptoms.
Prevalence for NPC
Based on the prevalence described above the number of potential NPC patients in the United States and in the EU is conservatively estimated to between 1,000 and 2,000 individuals in total. Diagnostic challenges may affect the number of potential patients. However, a treatment option could also increase awareness of the disease and assist in identifying more cases.
About Gaucher DISEASE
Gaucher disease is a rare, inherited metabolic disorder causing certain sugar (glucose) containing fat (lipids and especially glycolipids) to abnormally accumulate in the lysosomes of cells, especially within the bone marrow, spleen and liver, due to the lack of a certain enzyme (glucocerebrosidase). The symptoms vary greatly from patient to patient with some patients having few or no symptoms while others may experience significant complications. The usual symptoms of Gaucher disease include an abnormally enlarged liver and/or spleen (hepatosplenomegaly), low levels of circulating red blood cells (anemia) and blood cells promoting clotting (thrombocytopenia) and skeletal abnormalities. Like NPC, Gaucher disease is an autosomal recessive disorder.
Prevalence for Gaucher disease
Based on the prevalence above the total number of Gaucher disease patients in the United States and EU is conservatively estimated at between 10,000 and 15,000 individuals. Of the total market, Orphazyme focuses on the 10-30% with Gaucher disease type 2 or type 3, as well as type 1 patients with neurological symptoms as the treatment needs of these groups are not met by current treatment options.