By: Clay Wirestone
And wouldn’t it be great if that pill weren’t something advertised on late-night TV, but rather a legitimate treatment? A drug called rimonabant, introduced in Europe, seemed to fit the bill at first, but it was pulled from the market in late 2008 due to concerns about psychiatric side effects.
The story doesn’t end there, though. New research on animals suggests that a second generation of drugs may treat obesity without those side effects. A presentation at the International Congress on Obesity in Stockholm, Sweden, revealed a treatment that has the same weight-loss effect as rimonabant, but without impacting the brain.
What’s different? The new drug, currently called TM38837, does not affect peripheral organs and tissues. Rimonabant, however, didn’t discriminate. According to earlier research, rimonabant doubled the risk of disorders such as depression and suicide.
In their new work, scientists tried the second-generation drug on mice and rats. After a five-week course of treatment, the mice had lost 22 to 26 percent more weight than mice in a control group. The rats had lost 14 percent more than the controls. In both cases, weight loss from TM38837 was the same as weight loss from rimonabant. Separate studies, including dissections and behavioral tests, showed that the drug was less likely to impact the brains of test animals.
In a human study, the new drug was well tolerated by test subjects, with only a handful of mild side effects, including abdominal discomfort and diarrhea. Given the promising results, the scientists are continuing their work, and more information could be released in the fall.
“These findings, together with what we have seen in our first human study regarding the safety and tolerability, make this drug candidate a promising therapy for obesity and diabetes,” said Christian Elling, vice president of 7TM Pharma A/S in Denmark. “The lack of significant exposure in the brain seen in our preclinical experiments provides optimism” that the drug’s mechanism — targeting a specific cell receptor — is safe and effective.
As far as the researchers know, this is the first such drug candidate being tested in humans, “and these results indicate its development as a potential new treatment should be advanced,” said Elling, who presented the work at the obesity conference.
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news.bbc.co.uk/2/hi/health/7687311.stm (about earlier drug)