Orlistat cuts pounds, cholesterol levels: study

The prescription weight-loss drug orlistat helps obese adults shed pounds and lower their cholesterol levels - including those with diabetes or other risk factors for heart disease, according to a research review.

Orlistat, sold as Xenica by the drug company Roche, works by blocking the body's absorption of fat from food. Some studies have suggested that besides aiding in weight loss, the drug can cut high cholesterol levels and lower the risk of type 2 diabetes - two key contributors to heart disease.

The new review, of 28 clinical trials looking at orlistat coupled with a reduced-calorie diet, found that across studies, orlistat patients were 66 percent more likely than placebo patients to lose 5 percent of their body weight. They were 90 percent more likely to drop 10 percent of their initial weight.

Of the 28 studies, there were 17 one-year trials involving more than 10,000 patients who were randomly assigned to take daily doses of either orlistat or inactive pills, coupled with a fat- and calorie-restricted diet.

Pooled data from these studies showed that orlistat patients were twice as likely as those in the comparison groups to lose 10 percent of their body weight. They also showed generally better cholesterol levels, regardless of whether they had co-existing conditions such as diabetes, according to results published in the American Journal of Clinical Nutrition.

Drs. Brian Hutton and Dean Fergusson of the Ottawa Health Research Institute in Canada conducted the review. In the report, they state no financial interests in the findings.

A number of the studies the researchers reviewed focused on obese patients with type 2 diabetes or other risk factors for heart disease, including high cholesterol and high blood pressure. The benefits of orlistat on weight and cholesterol levels were seen in these patients as well.

"The positive and consistent findings of the included studies suggest that orlistat is highly effective in helping adults achieve greater weight loss than with a (calorie-restricted) diet and lifestyle changes alone," Hutton and Fergusson conclude.

Because orlistat blocks the body's absorption of a portion of the fat from foods, it can cause uncomfortable side effects such as gas, diarrhea and incontinence, particularly in the first weeks of treatment. In the one-year trials Hutton and Fergusson reviewed, the risk of gastrointestinal problems was 46 percent higher in orlistat patients.

The researchers also note that there is a "paucity" of studies comparing orlistat with other weight-loss agents.

"Such studies are needed to determine the relative effectiveness of therapies compared with one another," they write, "and would most ideally be performed by parties having no affiliation with the drug's patent holder."