A weight-loss drug popular in Europe failed to slow heart disease by a key measure in obese patients with fat around the middle, and it significantly raised the risk of anxiety and depression, U.S. researchers said on Tuesday.
More than 40 percent of patients who took rimonabant, sold as Acomplia in Europe, developed psychiatric problems, and one committed suicide, the researchers told an American College of Cardiology meeting in Chicago.
However, they said patients who got rimonabant did show signs of improvement in a secondary measurement of coronary artery disease, suggesting the drug should be studied further.
Rimonabant, manufactured by Sanofi-Aventis SA, is not available in the United States after an expert panel last year recommended against its approval because of concerns over psychiatric risks.
"What you have here is some mixed evidence for a slowing of progression and a definite increase in psychiatric adverse events," the study's leader, Dr. Steven Nissen of the Cleveland Clinic, said in an interview.
Nissen's team studied the drug in obese patients with heart disease to see if it could slow the progression of atherosclerosis, the buildup of fat, calcium and other deposits in the arteries.
They specifically studied patients with abdominal obesity, as this buildup of fat around the middle and the internal organs is linked with the most health dangers.
The study, published in the Journal of the American Medical Association, involved 839 patients in North America, Europe and Australia who got either rimonabant or a placebo for 18 months. Researchers used intravascular ultrasound to directly measure fatty deposits inside the arteries.
Drug improved weight loss, cholesterol
Patients who got the drug lost about 9.5 pounds and 1.8 inches from their waists. They also saw a 22.4 percent increase in high-density lipoprotein or HDL, the so-called good cholesterol, and improvements in other measures of heart disease.
But the study failed to meet its main goal of reducing the Percent Atheroma Volume, a measure of plaque in a cross-section of the arteries. It did, however, reduce the Total Atheroma Volume, a measurement of the total amount of plaque in the coronary artery.
To assess concerns that the drug increased the risk of psychiatric side effects, the researchers included patients with a history of such problems in both the treatment and placebo groups.
They found 43.4 percent of patients who got the drug had psychiatric side effects such as depression and anxiety, compared with 28.4 percent of patients who took the dummy pill.
There was little difference in the incidence of serious psychiatric side effects, they said. One patient in the placebo group attempted suicide during the study, and one in the treatment group committed suicide.
Trials to continue
Given the serious nature of the obesity epidemic, Nissen and colleagues think the drug deserves more research, and trials are currently underway.
Dr. John Rumsfeld of the Denver Veterans Affairs Medical Center and Dr. Brahmajee Nallamothu of the Ann Arbor Veterans Affairs Medical Center and the University of Michigan were less hopeful.
"While this promise remains, it certainly has faded," they wrote in a commentary in the journal.
Pending data from ongoing studies, they wrote: "The potential benefits are offset by the very real risks of depression and anxiety."