NZ study supports banned drug

About 17,000 people have taken Reductil in New Zealand. Photo / Herald on Sunday

New Zealand researchers have found a popular weight-loss drug to be safer than reported by an overseas trial that led to it being banned in Europe.

"The results are quite reassuring for the New Zealand population," said one of the researchers on the study, Dr Mira Harrison-Woolrych.

Sibutramine, sold under the brand Reductil, was originally developed as an anti-depressant, but it also reduces the appetite.

Despite the European ban, it remains available in New Zealand.

In the first three years from going on sale in this country in 2001, sibutramine was prescribed to about 17,000 overweight or obese patients, mainly women.

The intensive Medicines Monitoring Programme at Otago University followed up nearly 16,000 patients for a study that was published in the international journal Drug Safety.

This followed the overseas study, the Sibutramine Cardiovascular Outcome Trial (Scout), which produced preliminary results showing an increased risk of serious, non-fatal cardiovascular events among patients taking the drug.

But the trial was based on patients already at high risk of problems such as heart attack and stroke, a group specifically excluded under the drug's New Zealand licence.

Dr Harrison-Woolrychm - the Otago programme's director - and her colleagues say in their journal paper that the Scout study reported an overall risk of death 10-fold higher than was found in the study here.

The death rate in the New Zealand study - a general population with an average body mass index of 34 (the middle of the obese range) - was also much lower than in a study of more than 1 million overweight or obese Americans.

Dr Harrison-Woolrych said the lower New Zealand death rate might be partly because the Scout study's median age of patients was 63 - 20 years older than in the New Zealand study.

Being old is an independent risk factor for heart disease and stroke.

The Ministry of Health's Medsafe unit is reviewing sibutramine in light of the European suspension.

In January Medsafe reminded doctors not to prescribe the drug to patients who have had any of a range of heart conditions or a stroke.

Medsafe group manager Dr Stewart Jessamine said the Otago University study showed sibutramine was safer than had been found in previous studies.

"It still shows a small increase in risk, just not as large as others."

However, Medsafe had to evaluate the totality of evidence, not one study in isolation, Dr Jessamine said.

He was awaiting advice from the Medicines Adverse Reactions Committee, which considered sibutramine this month.

A commentary article in Drug Safety says the New Zealand study is not enough to resolve debate over the drug's safety.

"We have to wait for the final complete results of Scout and of other post-marketing surveillance systems before drawing definite conclusions and recommendations," said Andre Scheen of Liege University in Belgium.