London - Britain's state-run health service will get a partial rebate from GlaxoSmithKline if the company's new kidney cancer drug Votrient does not match up to a rival medicine in a head-to-head clinical trial.
The unusual deal, the first of its kind, hints at the type of complex arrangements that could become commonplace as Britain moves to a system of value-based drug pricing from the end of 2013.
Draft guidance from cost-effectiveness watchdog the National Institute for Health and Clinical Excellence (NICE) on Friday recommends Votrient for use on the National Health Service (NHS), as long as GSK offers the special price scheme.
The deal provides for a straight 12.5% discount to bring the cost of Votrient to the NHS into line with that of Pfizer's Sutent, and also guarantees a financial rebate if Votrient proves inferior to Sutent in the clinical trial.
The results of the study will not be known until mid-2012.
"If we fail to confirm that they are comparable in efficacy - which we do not expect - then we provide a rebate back to the NHS as a result," GSK's head of British operations, Simon Jose, told Reuters.
"We are moving in the direction where price is driven by value and value is driven by evidence, and therefore we can start to construct different sorts of arrangements where we can balance this off."
The exact scale of the potential rebate has not been disclosed. The monthly cost of Votrient and Sutent - both of which are tablets - is just under £2 000 per patient.
Carole Longson, NICE's health technology evaluation centre director, said the rebate scheme made Votrient a cost-effective proposition. The drug offers patients an additional option and, for some, a more favourable side effect profile, she said.
NICE expects to issue final guidance on Votrient in February 2011.
Votrient, also known by its chemical name pazopanib, is seen as a modest seller for GSK in the next few years, with global sales expected to reach $314m in 2014, according to consensus forecasts from Thomson Reuters Pharma.
Both Votrient and Sutent are so-called protein kinase inhibitors, a relatively new class of targeted cancer treatment. Other new drugs for kidney cancer have been rejected by NICE and GSK has previously failed to persuade NICE to endorse its Tyverb drug for breast cancer.
Jose said it was often difficult to demonstrate the full value of new cancer medicines initially and the idea of linking prices to longer-term scientific evidence could be a model for future negotiations between government and industry.
The British government outlined plans last week for a radical shake-up of medicines policy from the end of 2013, after which it will introduce a system of "value-based" pricing.