The NHS could save £84m a year by using a cheaper drug to treat a leading cause of blindness, research suggests.

NHS-funded research says both Lucentis and Avastin have a similar effect in preventing loss of sight when used for wet age-related macular degeneration.

Lucentis costs about £700 an injection and Avastin £60 - but Avastin is not officially approved for eye conditions.

Novartis, which markets Lucentis in the UK, is taking legal action against four NHS trusts for using the cheaper drug.

Aaron Osborne, global medical director of Novartis, told the Today programme that if the cheaper drug was used it would undermine the regulatory process.

When pressed by Today presenter Evan Davis over whether the NHS should save money and opt for the cheaper version, Mr Osborne said the debate is a "difficult one".

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