Closely watched experimental Parkinson's drug fails key clinical trial

Results deal blow to patient community and to drug developers Biogen, Denali Therapeutics

On Thursday, Biogen and Denali Therapeutics announced that their experimental treatment for Parkinson's disease did not demonstrate the ability to slow the progression of the neurodegenerative condition in a randomized clinical trial. This outcome represents a considerable setback to a scientific strategy that had generated significant enthusiasm among both advocates and researchers in the field.

The clinical trial involved 648 adults diagnosed with Parkinson's disease, who were randomly assigned to receive either a placebo or a medication aimed at inhibiting a protein known as LRRK2. The link between mutations in the LRRK2 gene and a rare, inherited form of Parkinson's was identified by researchers in 2004. Furthermore, in 2018, another group of scientists posited that inhibiting this protein could potentially provide benefits to all individuals suffering from Parkinson's disease.

The findings from Thursday's trial represent a notable retreat from the previously optimistic perspective regarding this therapeutic approach.