Two of the world’s largest pharmaceutical groups on Thursday said they would spin out their entire portfolios of HIV medicines into a jointly controlled company, heralding a radical new approach to the sale and development of drugs.

GlaxoSmithKline and Pfizer will contribute 11 marketed medicines and a further six that are currently being tested in patients into the new company with initial gross assets of £250m, annual sales of £1.6bn and operating profits of £870m, and a 19 per cent market share.