The safe slimming pill will bring fat profits

Obesity is an epidemic. A cure would be a goldmine, writes Sameena Ahmad

Take your weight in kilograms and divide it by the square of your height in metres. If the result is over 25, you are overweight. If it is over 30, you are obese. Don't panic - you are not alone.

According to recent statements by the World Health Organisation, we are in the throes of an obesity epidemic. The number of fatties world-wide has doubled in the past 10 years. Around 120 million people are classified as obese. The USA is the biggest culprit. A staggering one in three adult Americans is either obese or severely overweight. In Europe, a fifth of Italians and Germans are obese. The British are almost as bad, with 18 per cent ready for the fat farm.

The consequences are more than just a reduced quality of life. Obesity leads to a host of serious medical problems such as heart disease, cancer, diabetes, arthritis, infertility, back pain, depression and even gallstones.

The costs are huge. In the US, complications of obesity account for $45bn a year, or nearly 10 per cent of total healthcare spending. More than just overindulgence or weak will, obesity is increasingly being seen as an illness which can kill. The US drug regulator, the FDA, now classifies the condition as a disease - enabling sufferers to get anti- obesity drugs on prescription.

Even so, obesity is poorly treated at present, opening up a huge opportunity for the pharmaceutical industry.

Current drugs are limited to two kinds: amphetamines or phentermines, which speed up metabolism; and the newer serotonin uptake inhibitors or fenfluramines, which dampen appetite and which include some anti-depressants. Eli Lilly's happy pill Prozac is increasingly being prescribed for weight loss.

Among approved amphetamines in the US are Ionamin, Medeva's second-biggest selling product, SmithKline Beecham's aptly named Fastin and a whole range of cheap generics. The market-leading fat pill in the US is Redux, the serotonin drug developed by Servier of France and marketed by American Home Products. BASF is finally close to launching Meridia in the US, another serotonin drug initially rejected by the FDA last year because of fears it damaged the heart.

Indeed because both classes of drug act on the brain, side-effects can be serious. Long-term use of amphetamines can be addictive and there is little data on either type of drug to determine the effects of long-term use.

Dr Didier Renno from the Wilkerson Group, a management consultancy specialising in healthcare, says the risks of side-effects have restricted the size of the market in prescription anti-obesity drugs to $380m world-wide, tiny by pharmaceutical standards. In contrast, Americans alone spend $33bn a year on over-the-counter slimming aids. "People who are seriously overweight are desperate for a safe treatment. The potential is huge for a company which can make a such a drug," says Dr Renno.

Plenty of companies are trying. According to NatWest Securities, which estimates that there are nearly 30 anti-obesity drugs in clinical development, the prescription market could be worth $9bn in 10 years.

The biggest immediate hope is Roche's Xenical, due for launch in the US in a few months. The Swiss group's pill does not act on the brain, but locally to stop the stomach absorbing fat. Taken three times a day with meals, this treatment blocks almost a third of fat ingested with food, reducing weight by about 10 per cent in a year.

"For someone who is severely obese, the medical benefits of that loss can be substantial. And Xenical has a completely different safety profile from other drugs," said a Roche spokesman. Crucially for the FDA, which has given Xenical fast-track approval, Roche has long-term clinical data over two years on over 7,000 patients to prove its safety claims.

Kevin Scotcher at NatWest estimates the drug could be a blockbuster, worth $800m at peak. Alizyme, the UK listed group, is working on a similar drug which stops the gut absorbing fat and sugars, though it has not started clinical trials. Dr Richard Palmer, chief executive at Alizyme, says: "Obesity is a serious problem and is beginning to be seen in younger age groups. A safe drug is potentially worth millions."

A new generation of safe drugs could mean popping pills for obesity will become as standard as long-term treatment for hypertension. That could turn into a goldmine for the pharmaceutical industry.