Repurposed drug enters clinical trial for Lewy body dementia

The drug treatment, bosutinib, is currently used to treat a type of blood cancer called chronic myeloid leukaemia, but is now being repurposed in this new phase II, placebo-controlled trial. 30 people with Lewy body dementia will be recruited to the study, happening at Georgetown University Medical Center in Washington DC, US.

The connection between Lewy body dementia and Parkinson's

Lewy body dementia is the second most common type of dementia (after Alzheimer's) and is estimated to affect more than 100,000 people in the UK. As with Parkinson's, Lewy body dementia is linked to the presence of Lewy bodies - small clumps of protein (mainly alpha-synuclein) that form within brain cells.

Lewy body dementia and Parkinson's share similar symptoms but differ in how common and severe these symptoms are. For example, people with Lewy body dementia don't always experience the motor symptoms associated with Parkinson's. But for both conditions, it's hoped that targeting alpha-synuclein clumping will help to slow, or maybe even stop, progression.

Potential benefits of cancer treatments

Certain cancer treatments have attracted interest in recent years. In 2017, the leukaemia drug, nilotinib, entered a year-long phase II trial in people with Parkinson's after early research suggested it could reduce the levels of alpha-synuclein. And similar to nilotinib, bosutinib is believed to work by targeting the protein clumps that form in the brain, restoring dopamine levels, and reducing inflammation.

Dr Lynn Duffy, Senior Scientific Copy Writer at Parkinson's UK said:

"This new trial will be the first time that bosutinib has been tested in either Lewy body dementia or Parkinson's. The researchers will mainly be focusing on the safety of the drug, as well as looking at whether the treatment can change the levels of alpha-synuclein and dopamine in the blood and spinal fluid of the volunteers.

"There are currently no disease-modifying treatments available for these conditions. Trials such as this are vital if we are to find drugs that could help the many people across the world living with Lewy body dementia or Parkinson's. We'll be keeping a close eye on progress and reporting any developments."