For 18% of a group of 974 cancer drugs now in clinical development, there is “a probability” that they will reach the market, according to a survey conducted by researchers at the charity Cancer Research UK.

In the past, such studies have suggested that only 5% of cancer drugs in development go on to become standard treatments, say the researchers, who publish their findings in the current issue of Nature Reviews Drug Discovery.

The study also shows that during 1995-2007, the kinase inhibitors, a family of molecularly targeted drugs which include Genentech/Roche’s breast cancer therapy Herceptin (trastuzumab) and Novartis’s Glivec (imatinib) for leukaemia, were almost three times more likely to reach the market than other types of anti-cancer drug.

A better understanding of the basic biology of cancer has enabled the development of kinase inhibitors, which have fewer unpleasant side effects that traditional chemotherapy drugs, they say. Also contributing to the better success rates are improved drug discovery processes and advances in medicinal chemistry, while clinical trial design has also improved, due to better understanding of a patient’s genetic make-up and how they will respond to certain drugs.

"This analysis clearly demonstrates the benefits of developing molecularly targeted treatments for cancer,” said Dr Ian Walker, licensing manager at the charity’s commercial development arm Cancer Research Technology. “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. It’s clear that further significant achievements in cancer drug development will be dependent on continued research into new and relevant molecular targets,” he added.

Professor Herbie Newell, director of translational research at Cancer Research UK and co-author of the report, said the findings show that now is “a really exciting time for cancer drug discovery,” and he called on industry and academia to 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,” he emphasized.