Mesdopetam (IRL790)

Mesdopetam (IRL790) is a dopamine D3-receptor antagonist being developed for the treatment of levodopa-induced dyskinesias (LIDs), a severe form of troublesome involuntary movements commonly occurring in Parkinson’s disease. Mesdopetam also has potential in treating Parkinson’s disease Psychosis (PD-P).

Mesdopetam has a wide clinical potential for unmet medical needs in neurology. Firstly, the drug candidate is intended to treat people with Parkinson’s who develop LIDs, which is more than 30 percent of all people living with Parkinson’s. In the eight major markets worldwide, this equates to one million affected individuals.

Mesdopetam also has potential in treating Parkinson’s disease Psychosis (PD-P), which affects about 1.5 million people with Parkinson’s across the eight major markets worldwide.

Following a successful Phase Ib study, a completed Phase IIa study with 75 patients demonstrated compelling proof-of-concept with potential for superior efficacy, improving daily hours of ON-time without troublesome dyskinesias, versus current treatment options.

A Phase IIb study with 125 patients was completed with top-line results reported in January 2023. Mesdopetam demonstrated significant anti-dyskinetic effects as measured by UDysRS, a comprehensive scale measuring ON-phase dyskinesia with objective physician ratings and patient ratings. Additionally, mesdopetam displayed an adverse event and tolerability profile similar to placebo.

In early 2024, the company successfully completed an End-of-Phase 2 meeting with the American pharmaceutical authority, FDA, and has also received scientific advice from the European pharmaceutical authority EMA (February 2025). Both authorities consider that the studies and the data generated so far are adequate to move the program into Phase III.

About the recommended INN, mesdopetam

Since early 2020, IRL790 goes by the International Nonproprietary Name (INN), mesdopetam. The World Health Organization (WHO) concluded that IRL790 is unique in its mechanism of action and assigned a new INN, mesdopetam, that can become a new substance class in the existing classification system for pharmaceutical substances. The INN will serve to identify the active pharmaceutical substance of mesdopetam during its lifetime worldwide.

Solid intellectual property rights

Exclusivity based on patents

Mesdopetam is protected by a family of granted substance patents (composition of matter) in all major markets worldwide. Provided regulatory requirements are met, and potential grants of supplementary protection certificate (SPC) or patent term extension (PTE), exclusivity for mesdopetam can be prolonged well into the 2040s in all major markets.*

Exclusivity based on regulatory data protection

Independent of the patent-based exclusivity periods mesdopetam will also enjoy customary market exclusivity, for ten years from market approval in Europe and five years from market approval in the US, based on regulatory data exclusivity as a new chemical entity (NCE).

* A medicinal product can only be granted an SPC/PTE extension for one patent.