A gene therapy company that started life at the University of Oxford has signed an $842.5m (£627.3m) deal with an American start-up to commercialise a promising injectable treatment for Parkinson's Disease, sending its shares up by 20pc.

Oxford Biomedica will get an upfront payment of $30m when it transfers the drug to Axovant Sciences, a US company founded just three years ago by 32-year-old hedge fund manager-turned-biotech entrepreneur Vivek Ramaswamy.

There will be further payments when the gene therapy reaches certain milestones, such as completing clinical trials or gaining regulatory approval, to a possible total of $842.5m.

The agreement is significant for Oxford Biomedica, which made £37.6m in sales last year but is still loss-making and has a market capitalisation of just £565m.

A major part of the company's strategy is to sell or license out pre-clinical drug candidates to third parties, who then go on to develop and commercialise them. It has done deals like this in the past, but this is the first one in nearly a decade.