A new study on mice shows that the experimental drug ebselen may be able to treat bipolar disorder without the added side effects that come with lithium medications.
Researchers gave mice small doses of amphetamines in order to make them manic. They then gave them doses of ebselen and found that the mice were calmed again by the drug.
“In mice, ebselen works like lithium,” said Grant Churchill, researcher from the department of pharmacology at Britain’s Oxford University. “Now we urgently need to see if it works like lithium in people.”
For more than 60 years, lithium has been the most effective long-term treatment of bipolar disorder, as it is able to protect against mania and depression. Lithium however does have some side effects such as weight gain, thirst and kidney damage, which often cause people to stop taking their treatment and relapse into mania and depression.
“Ebselen is an experimental drug that has been tested in people for other conditions, and does not have problematic side effects like lithium does,” Churchill said.
Ebselen could be a potential treatment option for bipolar disorder without the added side effects. Churchhill, working with Sridhar Vasudevan, searched through the U.S. National Institutes of Health Clinical Collection, to find existing drugs that are safe but do not currently have a use. They screened the library and found that ebselen could be a potential lithium mimic, as it blocked the same enzyme that makes lithium effective in bipolar disorder patients.
“This is one of the first handful of examples of drug repurposing, where a new use has been found for an existing drug,” Vasudevan said.
Formerly, ebselen was in stage III clinical trials as a treatment for strokes, however never reached the market and is now out of patent.
In mice, ebselen showed similar effects to lithium in treating mania. Researchers have now started a small human study to see the effects on the brain functioning of healthy human volunteers. If this sample shows similar results to lithium, they intend to begin a second stage trial on patients with bipolar disorder.