Researchers who have found a way to bypass the legal patent on an expensive drug say others should follow suit.
Hepatitis C is carried in blood cells
Imperial College experts have developed a potentially cheaper version of an existing Hepatitis C drug by altering the molecular structure.
They have also called on other universities and charities to retain the rights to new discoveries, rather than sell them to big drugs companies.
The industry warned any such 'new' drug may need dedicated safety trials.
The work of Professor Sunil Shaunak, an expert on infectious diseases, and his colleague, Steve Brocchini, from the London School of Pharmacy, was funded by, among others, the Department of Trade and Industry and the Wellcome Trust.
The most effective drug treatment for the Hepatitis C virus is a version of a naturally-occurring molecule called interferon, which has been modified by coating it with sugar to allow it to remain in the body for longer.
The patent for the resulting drug - pegylated interferon - ruled out any other pharmaceutical which involved interferon coated with sugar.
However, the Imperial team found a way to place the necessary sugar elsewhere on the interferon molecule instead, effectively creating a new medicine not covered by the patent.
They plan to find a way to develop and market this alternative without involving pharmaceutical firms, at a fraction of the cost of the original medicine.
Professor Shaunak said: "As far as we're concerned, the end-game is the cure - you can get to the end-game in several different ways, and we have found a different way of doing it."
"What we have to recognise is that we have a real opportunity to cure infectious diseases in the developing world.
"At the current price, only a fraction of the number of people who could benefit from the drug will actually receive it."
Success for sale
Currently, many of the scientific advances which eventually lead to effective treatments are developed within universities or by researchers working for charities, but that 'intellectual property' is then sold to pharmaceutical companies who bring the product to market.
Professor Shaunak called for a different approach - for academic institutions to go into competition for cures with 'big pharma'.
"We in academic medicine can either choose to use our ideas to make large sums of money for small numbers of people, or to look outwards to the global community and make affordable medicines."
A spokesman for the Association of the British Pharmaceutical Industry said that should this prove to be a 'new' medicine, then the same costly and time-consuming safety trials would need to be undergone before the drug could be marketed.
"Even if these are successful, you'd have to invest in commercial development to manufacture, distribute and promote the usage of your drug."
He said that pharmaceutical companies were already working hard to ensure medicines get to patients in the developing world, and often chose not to enforce patents.
The pharmaceutical company Roche, which produced the original version of pegylated interferon, said that it sought patents in order to guarantee the resources to re-invest in further 'cutting edge advances'.
A spokesman added: "Roche is committed to ensuring that as many people as possible can gain access to our medicines, many of which have transformed once deadly diseases into manageable and even curable conditions."