The American Heart Association (AHA) accepted an $11 million donation from a drug company that produces a thrombolytic - a drug that breaks down blood clots - while preparing its guidelines on stroke management. The AHA recommends the drug, which is produced by Genentech, in its review.

This incident is cited in an editorial in the prestigious medical journal The Lancet as part of an argument that medicine is now badly tainted by commercial interests.

The journal also points to another example where the researchers completed trials for biotech products in which they had direct financial interests. Moreover, the researchers failed to tell the patients participating in the trials that other patients had died while using the same products, and that other, safer options were available.

Another study has discovered that 90 per cent of the authors of ‘best practice’ guidelines for drug companies had not revealed that they had either received research funding from the pharmaceutical industry or had acted as consultants to it.

These conflicts of interest happened just as multinational pharmaceutical companies reported their best-ever year for sales - with over $155 billion being spent on drugs in 2001, almost double the 1997 figure.

This pressure culminated in an agreement among the editors of the leading medical journals last year to prevent any further conflicts of interests among authors of research papers. The Lancet doubts if the agreement goes far enough, and suspects that it has simply been ignored by medicine.

'How tainted by commercial conflicts has medicine become? Heavily, and damagingly so, is the answer,' states the journal’s editorial. 'Do doctors have the courage to oppose practices that bring the whole of medicine into disrepute?' (Lancet, 2002; 359: 1167).