Targeted Genetics has bought full rights to its preclinical Huntington’s disease programme from Merck & Co’s Sirna Therapeutics unit and, in return for the rights and intellectual property, will pay royalties on any future sales.

The two firms first partnered in 2005 to target the gene responsible for Huntington’s using the adenovirus vector approach to deliver expressed RNAi. Huntington’s is a neurodegenerative disease caused by a genetic mutation that produces a protein toxic to certain brain cells. The subsequent neuronal damage leads to the movement disorders, psychiatric disturbances and cognitive decline that characterise this disease, which appears in one in every 10,000 Americans alone.

Sirna has also handed over to Targeted Genetics a licensing agreement with Iowa University for the AAV vector programme. "This moves all of the key pieces of this programme to Targeted Genetics and gives us exclusive rights and direct involvement with the University of Iowa to expedite the programme," said H. Stewart Parker, president and chief executive officer of Targeted Genetics. "This programme is our primary proof of concept in the area of expressed RNAi, which we believe could present multiple product opportunities to help patients who currently have little hope for treatment, such as those with HD."

The firm says AAV vectors could show benefits over current methods of delivering genetic material because they express for long periods of time and therefore permit infrequent dosing – an advantage when administering a therapeutic directly to the brain. Lead compounds have been identified in animal studies and are being evaluated to take forward into man.

Additional terms of the deal were not disclosed.