IBS drug linked to five deaths may soon be back

A drug for irritable bowel syndrome (IBS) which was linked to the deaths of at least five patients, within nine months of being licensed, may soon be back on the market.

An advisory panel to the Food and Drug Administration (FDA), the American drug regulator, is recommending the reintroduction of Lotronex (alosetron hydrochloride), manufactured by GlaxoSmithKline.

The panel says that there should be restrictions on who can prescribe it, and patients need to be carefully followed up. The FDA may not endorse the panel’s recommendations, but it is likely to do so.

Lotronex was withdrawn in November 2000 – just nine months after it received a licence – following reports of five deaths and 70 cases of serious adverse reactions. These reactions included ischaemic colitis (fever and gut pain caused by an insufficient blood supply) and severe constipation.

Peter Traber, chief medical officer of the drug company, described the panel’s recommendation as ‘a very positive step forward for patients who need this drug’. This view was countered by Sidney Wolfe, of Public Citizen’s Health Research Group, a medical watchdog group in the States, who said the decision would ‘lead to more cases of ischaemic colitis and more deaths’.

Lotronex was the first drug required to come with a full treatment guide under ‘patient-power’ regulation. The guide warned that the principal side-effect revealed in trials was constipation.

Hailed as ‘a promising aid for irritable bowel syndrome’ (Drug Infoline, December 1999), a 12-week trial of 370 IBS sufferers found that the drug was effective in women compared with a placebo.

As well as being a drug intended only for women, it was also only supposed to treat the diarrhoea form of IBS.

However, the trial didn’t pick up the serious adverse reactions with Lotronex that were soon reported to the FDA. These included cases of intestinal damage due to a reduced blood flow, and severely obstructed or ruptured bowels as a complication of severe constipation.

Within four months of its launch, six women needed hospital treatment and three of those underwent surgery after taking the drug.

By the time GlaxoWellcome agreed to withdraw it, 34 patients had been treated in hospital, 10 others had undergone surgery and three had died (Lancet, 2002; 359: 1491-2).