Modern cancer drugs more likely to get to market

LONDON (Reuters) - Nearly one in five cancer drugs entering development now reach the market, a remarkably good success rate given the high level of failures in other disease areas, British researchers said on Friday.

A study by Cancer Research UK, based on 974 cancer drugs starting initial Phase I clinical trials since 1995, calculated there was an 18 percent probability that those in human tests would make it to commercial registration.

The last time this was measured, in 2004, the figure was estimated at 5 percent.

The sharp improvement is due to more targeted "intelligent" drug development based on a better knowledge of the biology of cancer, according to Herbie Newell, the British cancer charity's director of translational research.

"These findings highlight the fact that we are working in a really exciting time for cancer drug discovery," he said.

In the past, most cancer drugs were cytotoxic agents, designed to kill cancer cells. Such cytotoxic drugs also kill healthy cells that multiply rapidly, resulting in serious side effects such as sickness, hair loss and risk of infection.

By contrast, modern drugs are much more precise weapons because they target specific molecular switches involved in tumor growth, giving rise to fewer side effects.

The new research, published in the journal Nature Reviews Drug Discovery, found a family of molecularly targeted drugs called kinase inhibitors were almost three times more likely to reach patients than other types of anti-cancer drug.

Well-known examples of kinase inhibitors include Roche and Genentech's breast cancer drug Herceptin and Novartis's Glivec for leukemia.

Oncology is the fastest-growing section of the global pharmaceuticals market, with sales expected to increase by 15 to 16 percent in 2009, against just 4.5 to 5.5 percent for the drugs market as a whole, according to IMS Health.

Scientific advances in cancer treatment have encouraged many large drug companies to step up their investment in cancer research in recent years, resulting in a rapidly expanding line-up of targeted therapies.

Other notable products include Roche/Genentech's Avastin, Amgen's Vectibix, GlaxoSmithKline's Tykerb, ImClone's Erbitux and Pfizer's Sutent.

The arrival of such targeted treatments has extended lives for many cancer patients but their high cost - typically running into tens of thousands of dollars - means they can be a strain for cash-strapped healthcare budgets.

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