'Intelligent' cancer-drug development has spurred a leap in the proportion of drugs reaching patients, according to a study by Cancer Research UK.
In a study published in Nature Reviews Drug Discovery, scientists studied 974 cancer drugs in clinical development and calculated there was an 18 per cent probability that those drugs entering the clinic would make it to market.
It was previously estimated that only five per cent of cancer drugs in the pipeline become standard treatments for the disease.
The research also indicated that between 1995 and 2007, a family of molecularly targeted drugs called kinase inhibitors were almost three times more likely to reach patients than other types of anti-cancer drugs.
The researchers believe that a better understanding of cancer's basic biology has enabled the development of this type of drug, which includes Herceptin for breast cancer and Glivec for leukaemia.
Molecularly targeted drugs are usually less toxic, resulting in fewer side effects.
They are also more successful in clinical trials.
Traditional chemotherapy drugs target cancer cells but also kill healthy cells, which is why they cause unpleasant side effects such as sickness, fatigue and hair loss.
Dr Ian Walker, licensing manager at Cancer Research Technology, Cancer Research UK's commercial development arm, said: 'This analysis clearly demonstrates the benefits of developing molecularly targeted treatments for cancer.
'It highlights the fact that understanding more about the basic biology of cancer is making a real difference to the success rate of new anti-cancer drug development.' Better understanding of a patient's genetic make-up and how they will respond to certain drugs has also led to improvements in clinical trial design.
As drug development continues to advance, minimising the number of drugs that fail to make it to market will be vital, as the cost of discovery and development of drugs that don't reach market is borne by those that do.
Professor Herbie Newell, co-author of the study and Cancer Research UK's director of translational research, added: 'We strongly believe that both industry and academia must improve the availability of data related to failed as well as successful drug development programmes.
'The sharing of such information can only be beneficial for clinical, scientific and commercial reasons and will help measure our progress as well as pinpoint areas for improvement.'
