FDA Accepts New Drug Application for IRLAB’s Mesdopetam for Dyskinesia

The U.S. Food and Drug Administration (FDA) has accepted an investigational new drug application for mesdopetam (IRL790), an experimental therapy for reducing levodopa-induced dyskinesia, or involuntary movements, in people with Parkinson’s disease.

This move by the FDA will allow for the enrollment of U.S. patients in a planned Phase 2b/3 clinical trial (NCT04435431), in addition to enrolling in Europe, according to Integrative Research Laboratories (IRLAB), which is developing mesdopetam. Patient recruitment is anticipated to start by the end of the year.

“We are pleased to receive acceptance of the IND. The FDA clearance of the IND is a quality stamp on the mesdopetam project and validates mesdopetam as a safe and tolerable drug candidate,” Nicholas Waters, PhD, IRLAB’s CEO, said in a press release.

Parkinson’s disease is characterized by the loss of neurons, or nerve cells, that produce the neurotransmitter dopamine — a chemical messenger essential for muscle control. Levodopa, which is a precursor to dopamine, has long been one of the gold standards for Parkinson’s treatment.

However, as the disease progresses, patients typically need to gradually increase their levodopa dosage, resulting in a condition known as levodopa-induced dyskinesia, or LID, characterized by uncontrollable involuntary movements.

Mesdopetam is a potential treatment for LID. It works by blocking specific dopamine receptors called D3 receptors, which have been implicated in the development of LID. It is thought that, by blocking only D3 receptors, LID can be minimized while other beneficial effects of dopamine treatment can be maintained (through its action on other receptors).

The Phase 2b/3 trial will investigate the efficacy and safety of mesdopetam. Efficacy will be evaluated using patient diaries and measured by the amount of good “on-time” — when dopaminergic treatment is working and dyskinesia is not experienced.

It will include 140 patients who will be randomly assigned to receive one of three doses of mesdopetam or a placebo twice daily for 84 days.

Plans for the trial are based on the positive results from previous Phase 1, Phase 1b (NCT03531060), and Phase 2a (NCT03368170) studies, in which patients given 7.5 mg of mesodepetam twice daily showed significantly longer daily good on-time than those on the placebo.

“The treatment effects seen in the previous Phase 2a study exceeds the results for other treatment strategies in troublesome dyskinesias,” said Joakim Tedroff, PhD, IRLAB’s chief medical officer.

“When mesdopetam was given in addition to standard Parkinson medication, patients experienced considerably longer periods of good daily motor function without aggravated involuntary movements improving the daily function in these severely affected patients,” Tedroff said.

Along with the planning of the study, applications also are being prepared to submit to regulatory authorities and ethics committees in certain European countries.

“We believe that mesdopetam has a very good chance to offer a completely new and better treatment for the large group of Parkinson’s patients experiencing daily complications and reduced quality of life due to levodopa-induced dyskinesia,” Waters said.