A cancer charity has unveiled plans to revive research into promising drugs whose development has been shelved.
Many drugs are never fully examined
Cancer Research UK plans to carry out new clinical trials of anti-cancer agents whose development has not been pursued by the pharmaceutical industry.
It is hoped the initiative will ultimately see effective new drugs reaching the market.
Drug companies have a large pool of potential anti-cancer molecules - but prioritise only the most promising.
This leaves potentially effective treatments on pharmaceutical companies' shelves.
Cancer Research UK has set up the Clinical Development Partnerships (CDP) as a joint initiative with its commercialisation arm to re-investigate their potential.
Effectively, the charity will "borrow" a drug from a company and conduct early clinical trials at no cost to the company.
If the drug looks promising, the company retains the option to develop and market the drug, but with the charity receiving a share of any revenues.
Harpal Kumar, chief operating officer of Cancer Research UK, said: "Cancer Research UK has set an ambitious target to double its drug development activity over the next five years and we are seizing an opportunity to seek out new treatments that otherwise might not get developed."
There are many reasons why potential treatments do not make it to market.
Science has progressed so rapidly in recent years that there are more compounds available than commercial resources to investigate them.
Drug development is time-consuming and expensive - a new anti-cancer drug can take in excess of 10 years and £500 million to develop.
Therefore, anything that does not look extremely promising is not developed by a pharmaceutical company.
Mr Kumar said: "The drug companies have these potential treatments trapped in their pipelines and we have the expertise and capacity to release this potential."
Dr Richard Tiner, medical director of the Association of the British Pharmaceutical Industry, said: "This is a simple, rapid and cost-effective way in which pharmaceutical companies can boost their product lines.
"Companies will retain intellectual property rights to their original molecules and first option to view the trial data, so should have no reservations about loaning these compounds for further investigation."
Professor Alex Markham, chief executive of Cancer Research UK, said: "Making the leap from something that looks promising in the laboratory to testing it in patients is one of the most challenging steps in drug development.
"There is a real potential here for us to develop a raft of new anti-cancer drugs.
"This may include new medicines to tackle the rarer cancers - those that tend to be lower down a business' priority list because they are less profitable."