Still searching upwards. Drug trial blow a bitter pill to...

Still searching upwards.

Drug trial blow a bitter pill to swallow
BY NYSSA SKILTONMEDICAL AND TECHNOLOGY REPORTER

15/12/2008 6:38:00 AM

One of Australia's leading immunologists has spoken out against drug development practices after a pharmaceutical company axed trials of a potentially lifesaving cancer drug.

Professor Chris Parish, who leads the cancer and vascular biology group at the Australian National University's John Curtin School of Medical Research, spent 20 years developing the drug, PI-88.

PI-88 was at phase 3 of clinical trials the last major hurdle before a drug is available to the public when its sponsor Progen Pharmaceuticals announced in July that it was terminating the trials.

The Australian-based drug company said a number of factors ''that impacted the commercial return'' for the trial triggered the termination.

But analysts say the cash-rich company has not given any valid reason for dropping the trial.

PI-88 is a sugar-based drug which inhibits the growth and spread of tumours. It is a ''double hit'' anti-cancer drug: it prevents growth of new blood vessels that supply a solid tumour and it blocks enzymes called heparanase to inhibit the spread of cancer throughout the body.

Professor Parish said PI-88 was a new class of anti-cancer drug and trials showed it worked.

The most promising results were for liver cancer.

Liver cancer is the fourth most common cancer in the world. Treatment usually involves surgery and there are few options for post-operative treatment. About 50 per cent of these patients have recurrent cancer within 12 months and most do not survive beyond three years.

When patients received PI-88 after surgery during the phase2 trial, there was a 35 to 40 per cent reduction in cancer recurrence during the following 12 months.

In April last year, Progen chief executive Justus Homburg said ''they were excited with the strong results PI-88 demonstrated''.

''These data give us the confidence to aggressively pursue the development of PI-88 towards registration and commercialisation.''

PI-88 was due for release in 2010.

Professor Parish said he heard about Progen axing the trial from a friend who read about it on the internet.

''It was bloody awful. It was devastating actually,'' he said.

''It's 20 years of work and if it was on scientific grounds, that's fine [but] the reasons for terminating the phase 3 trial were based on logistics.''

Progen had spent tens of millions of dollars developing the drug over 10 years.

The company blamed ''slower than expected'' recruitment of patients for the trial and slower than expected regulatory processes in China, Korea and Vietnam where the trial was to take place.

It also blamed the launch of a competitive phase 3 trial of Bayer and Onyx's drug Nexavar.

Progen would not respond to questions from The Canberra Times.

Bioshares analyst David Blake said Progen had not sufficiently explained the demise of the trial.

He said he understood Progen had two licensing opportunities with the drug, but the company had rejected them.

''I don't think there is any future for PI-88. I don't think it's worth a cracker,'' he said.

Professor Parish said it was ''unbelievably frustrating'' to try to take the drug further while Progen owned the intellectual property rights on his work.

''If the intellectual property is just held by someone, and not utilised properly, then no one else can actually benefit from that intellectual property,'' he said.

''I think we need an alternative route for developing new drugs.''

http://www.canberratimes.com.au/news/local/news/general/drug-trial-blow-a-bitter-pill-to-swallow/1386153.aspx?storypage=2