Neurology Central

New orphan drug designation for the treatment of levodopa-induced dyskinesia associated with Parkinson’s disease

A recent announcement by Addex Therapeutics (Geneva, Switzerland) has highlighted the designation of dipraglurant by the US FDA as an orphan drug for the treatment of levodopa-induced dyskinesia associated with Parkinson’s disease (PD-LID). The development signals a key sign of support for the use of the drug in this rare disease.

Dipraglurant was developed as a small molecule inhibitor of the metabotropic glutamate receptor 5 (mGluR5), with the potential for use in combination with levodopa or dopamine agonists, or as a standalone treatment for Parkinson’s disease levodopa-induced dyskinesia, other motor and non-motor symptoms of Parkinson’s disease and other movement disorders.

To date, the drug has successfully completed Phase II proof-of-concept testing in Parkinson’s disease (PD) patients suffering from debilitating levodopa-induced dyskinesia (LID), which currently does not have any dedicated approved treatments. Results indicated a good safety and tolerability profile as well as a significant reduction in LID severity at both 50 and 100mg doses, including reduced dystonia severity and chorea.

“Orphan drug status for dipraglurant in PD-LID is an important regulatory milestone for us and recognizes the therapeutic benefits that dipraglurant can bring to PD patients,“ explained Sonia Poli (Addex Therapeutics). Addex will now receive a number of benefits associated with the designation of orphan drug status, including reductions in further development costs and 7 years US market exclusivity following the launch of the product.

The development team are now conducting an mGlu5 receptor occupancy clinical trial and hope to commence a Phase III pivotal trial in PD-LID in the near future.

Source: Addex Therapeutics press release