A trial of the drug fialuridine (FIAU) on hepatitis sufferers has been stopped after several died and others became seriously ill.

The trial was being managed by the US National Institutes of Health (NIH) with pharmaceutical giant Eli Lilly, which was marketing the new drug.

One man in the trial has started proceedings against the NIH and Oclassen Pharmaceuticals, a small drugs company based in California that developed the drug.

A lawsuit against Eli Lilly is pending, and more are expected.

Bristol Meyers dropped their license for the drug in 1988 after unsuccessful animal studies. Oclassen took it on after their research showed it could be developed to treat chronic hepatitis B. After a successful 10 day trial, the FDA granted Oclassen approval to carry out a four week trial among 24 patients without HIV infection. Various doses were administered; those on the middle doses showed a remarkable improvement. On the strength of that, Eli Lilly agreed to pay $7.5m to share the development and marketing rights.

However, four months after the trial ended, a 60 year old trial member died from liver failure. Another trial member reported tingling in his feet, and two more reported serious side effects.

Within a month, five more trial members had died, two after receiving liver transplants, and two more were gravely ill.

The FDA concluded that there was no possibility that these reactions could have been detected in animal studies or short studies on patients.