Immunotherapy is a breakthrough technology that scientists hope will one day lead to cures for previously untreatable cancers.

Businesses are now competing to bring drugs to market - it's a process that requires huge amounts of investment.

This is part of the BBC's Disruptors series. You can read the full article here.

Producers: Rebecca Fordham, Philippa Goodrich; Camera: Peter Page, Tracey Langford; Video editor: Sara Hegarty