(Adds comment from GlaxoSmithKline CEO, more on new market models)
DAVOS, Switzerland, Jan 21 (Reuters) - More than 80 international drug and biotech firms urged governments to work with them to combat drug-resistant superbugs which could kill tens of millions of people within decades unless progress is made and new antibiotics found.
In a declaration at the World Economic Forum in Davos, they called for coordinated efforts to cut unnecessary use of antibiotics and support development of new ones, including by creating new economic models and investing in research.
GlaxoSmithKline Chief Executive Andrew Witty said the difficulty of finding new antibiotics was highlighted by the fact that mass screenings of hundreds of millions of chemicals at GSK and two other large firms over nine years had yielded zero potential new drugs.
"That's not because we are all really stupid. It's because it is a really, really difficult space to make progress in," he said in Davos.
The 83 pharmaceutical companies urged governments around the world to commit money "to provide appropriate incentives".
Since new antibiotics will likely be kept in reserve for emergencies, possible new market models could include upfront payments that would delink profits from sales volumes.
Any use of antibiotics promotes the development and spread of so-called superbugs - multi-drug-resistant infections that can evade the medicines designed to kill them.
International alarm about the superbug threat is rising after the discovery in China of a gene called mcr-1 that makes bacteria resistant to all known antibiotics.
"For the world to continue to have new antibiotics, we need investments in basic science and novel incentive models for industry R&D, and to protect our existing treatments, we need new frameworks for appropriate use," said Paul Stoffels, chief scientific officer of Johnson & Johnson.
Former Goldman Sachs chief economist Jim O'Neill was asked in 2014 by Britain's prime minister to conduct a full review of the problem and suggest ways to combat it.
In his initial report, he estimated antibiotic and microbial resistance could kill an extra 10 million people a year and cost up to $100 trillion by 2050 if it is not brought under control.
While the problem of infectious bugs becoming drug-resistant has been a feature of medicine since the discovery of the first antibiotic, penicillin, in 1928, it has grown in recent years as drugmakers have cut back investment in the field.
In their Davos declaration, the companies pledged to encourage more appropriate use of new and existing antibiotics, including more judicious use of the drugs in livestock.
They also promised to increase investment in R&D "that meets global public health needs" and work to ensure affordable access to antibiotics all over the world, at all levels of income.
Other companies signing up to the declaration include Merck , Pfizer, Sanofi, Novartis and AstraZeneca. (Reporting by Kate Kelland in London and Ben Hirschler in Davos; Editing by Dominic Evans and Peter Graff)