The companies also used its "key opinion leaders" and charities they sponsor, including the Royal National Institute of Blind People (RNIB), to raise safety worries about the cheaper drug, an investigation by the British Medical Journal (BMJ) has found.
The General Medical Council (GMC) has played its part and has refused to issue guidance on using the cheaper drug, so leaving doctors confused and worried that they may be open to legal claims if they used the alternative.
The controversy centres on two AMD drugs, Lucentis (ranibizumab) and Avastin (bevacizumab). Both are manufactured by Roche, although Novartis has marketing rights for Lucentis in Europe. The difference in cost is staggering; the UK's NHS spends lb244m a year on Lucentis, but using Avastin would save it lb102m a year.
Although Avastin was once the preferred drug for AMD, it was always prescribed 'off-label', which means it was used for a condition for which it had not been licensed to treat, a common practice in medicine. It is still regularly used in Europe and the US.
(Source: BMJ, 2015; 350: h1654)