Gel capsules that partially fill the stomach before a meal can help people lose weight and keep it off, the European Obesity Congress was briefed on Sunday.
The hydrogel capsule was first reported in 2010, when it was called Attiva. Now, like Plenity, it has been tested on over 400 people. It worked in only 59% of people, but in those, doubled their chances of losing 5% to 10% of their body weight.
Diet pills have had a checkered history and only one has been approved for use by the NHS in the UK – Xenical – which is not very popular because of its mode of operation. It prevents the fat from being absorbed, so that it passes directly through the body and can cause problems in the stomach or intestine.
Plenity, manufactured by the US company Gelesis, is technically a medical device and not a drug, so it does not require such extensive testing. The capsules contain hydrogel made of cellulose, which is found in fruits and vegetables and citric acid. Three capsules are taken with two glasses of water 20 minutes before a meal. They absorb water and swell in the stomach.
"What happens is that these small particles are released into your stomach and turn into a gel. This gel takes up about 250ml of your stomach – about a quarter of its volume, "said Dr. Harry Leider, medical director of Gelesis.
"This gel – it's like a chewed vegetable – mixes with the food. This makes you feel fuller when you eat, not to eat as much. This is the main mechanism. "
The gel is not absorbed. It passes through the small intestine, then reaches the colon where it is broken down, the water is reabsorbed and what is left in the faeces.
"As there is no chemical interaction with the body, it is not absorbed, it is mostly mechanical. It has a really good safety and tolerability profile, "he said. "That is why it is regulated as a device and not as a medicine.
"It is recommended that it be a help in weight control in conjunction with diet and exercise. We encourage patients to contribute to diet prudently and to focus on exercise because we know this will help people succeed. Nothing is the silver bullet. This is a new tool in our arsenal. "
The study involved 436 people, half of whom took the capsules while the other half had a placebo. Everyone was overweight or moderately obese and trying to lose weight through diet and exercise. The average starting weight was about 100 kg 15st 10lb). Those in the placebo group lost 4.4% of body weight and those who took the active capsules lost 6.4%. But adjusting the differences, including initial weight, age and sex, Leider said, there was a 2% weight loss over placebo.
Obesity experts said the capsules, which could be available at pharmacies next year, may be helpful.
"I would warn against magic bullets, but for a certain group of consumers who are doing the right things in terms of diet and exercise, this can help keep them on track," said Professor Jason Halford of the University of Liverpool, at the Glasgow meeting. where the test results were presented.
"This could be a great help to millions of people. It is well tolerated and increases satiety for people to eat less. You do not need a surgeon to do it, just buy it in a box and swallow a pill. It seems easy and effective, so millions could benefit, "said Dr. Nathalie Farpour-Lambert, president of the European Association for the Study of Obesity.
But Professor Helen Stokes-Lampard, president of the Royal College of GPs, issued a note of caution. "This certainly sounds like an interesting development and the non-invasive nature of a pill would be appealing to many patients and health professionals," she said.
"But we should caution ourselves to think of this as a miracle cure for weight loss, since non-medical approaches to a healthy lifestyle should always be explored in the first instance so that as a society we do not become dependent on medical treatment . interventions. "