AMT gains orphan designation for LPL therapy

The treatment, if approved, will be the first to tackle, the rare LPL genetic disorder that causes the accumulation of large quantities of fat in blood. Gene therapy specialist AMT presented promising results from Phase I/II clinical trials at last week's 10th Annual Meeting of the American Society of Gene Therapy in Seattle, US. The study showed that AMT 011 was safe and effective in all eight subjects with LPL Deficiency involved in the trial. LPL deficiency is an inherited condition caused by a mutation in a gene that codes for the enzyme LPL that clears of triglycerides from the bloodstream. The dysregulation of this enzyme leaves LPL patients with extremely high triglyceride (TG) levels in their blood plasma which can lead to (potentially lethal) pancreatitis as well as predisposing sufferers to cardiovascular diseases. Exact data on the prevalence of LPL deficiency are not available, but AMT estimates the worldwide population of LPL deficiency is around 4,000 patients. Currently, the only effective treatment for these patients is a severe reduction in the consumption of fat, a regimen to which many patients have difficulty adhering. AMT 011 is an adeno-associated viral (AAV) vector, which can substitute normal genes for genes containing disease-causing mutations. This sort of vector is not linked to human disease and is therefore considered relatively safe. AAVs are regarded as one of the most exciting approaches to gene therapy. To fight LPL deficiency, AMT 011 expresses the missing LPL enzyme, thus enabling the clearance of trglycerides from bloodstream. If AMT 011 makes it into the market, it will be the first commercially available AAV-based treatment on the market. The technology that AMT is using has been developed by Targeted Genetics, a Seattle-based company. Last December AMT acquired a non-exclusive licence to two patents developed by Targeted Genetics covering adeno-associated virus vectors. Although AAV vectors were originally developed for use in the treatment of diseases resulting from gene mutations, Targeted Genetics has leveraged its AAV technology platform into additional indications with significant market potential. The company hopes that AAV-based delivery of genes encoding therapeutic proteins will present an attractive alternative or complement to systemic protein therapy AMT has found its potential niche in the development of drugs to treat orphan diseases, which are those that affect less than 200, 000 people in the world. Biotech companies are starting to focus on rare diseases due to the special laws that are in place for orphan drug development. These permit companies to apply for special licenses that guarantee exclusive rights - and the ability to charge high prices. "The market for orphan drugs in terms of money is very interesting due to its high return on investment",​ said Hans Herklots, a spokesperson for AMT. In March 2004, AMT 011 obtained the Orphan Drug Designation from the European Medicine Agency, which guarantees 10 years of marketing exclusivity in Europe. In the US, the designation of orphan drugs, apart from the 7 years of exclusive rights, also allows AMT to apply for research funding and tax credits for clinical studies. "These designations are key to our strategic focus on rare disease and underpin our business model​," said Ronals Lorijn, CEO of AMT. The company expect to file for market authorization in Europe in the first quarter of 2008, followed by filings in the US and Canada. The Orphan Drug Designation in the US came two days before the company said yesterday they are going to launch an Initial Public Offering (IPO) on Euronext Amsterdam. The company expects to obtain around $450m from the public offering.