Pridopidine is an investigational sigma-1 receptor agonist for the treatment of amyotrophic lateral sclerosis (ALS).

Teva Pharmaceuticals was originally developing the treatment — which exhibits potential neuroprotective effects with a favorable safety profile — but Prilenia Therapeutics has since acquired the rights to further develop it.

How does pridopidine work?

Pridopidine is a small molecule that binds to the sigma-1 receptor on nerve and glial cells, which are the cells that support nerve cells. Scientists think that the sigma-1 receptor may play a role in protecting the nervous system against neurodegenerative diseases, including ALS.

Research has shown that pridopidine can affect the sigma-1 receptor pathway and provide protection for nerve cells against injury. It also has been found to enhance the secretion of brain-derived neurotrophic factor, known as BDNF, and glial cell line-derived neurotrophic factor, called GDNF. BDNF and GDNF are proteins that help keep nerve cells healthy. They also promote the growth and development of nerve cells.

In addition, the molecule has been shown to help restore the function of synapses, which are the connections between nerve cells and nerve cells and muscles.

Pridopidine in clinical trials

A Phase 2/3 clinical trial, called the HEALEY ALS Platform – Regimen D Pridopidine (NCT04615923), currently is investigating pridopidine as a treatment for ALS. The study is enrolling roughly 160 adults with ALS, by invitation, at one of 54 locations in the U.S.

It’s part of the HEALEY ALS platform trial (NCT04297683), which is investigating different treatments in patients with ALS at the same time to try and speed up their development.

During the Regimen D Pridopidine study, patients will receive either 45 mg capsules of pridopidine or a placebo twice a day for 24 weeks (nearly one year). Investigators will then assign them to the treatment or placebo group in a 3:1 ratio. At the end of 24 weeks, they will compare the change in score on the ALS functional rating scale-revised (ALSFRS-R) from baseline (the study’s start) between patients receiving the medication and those on the placebo to see how the disease has progressed.

Changes also will be assessed in a number of other functional outcomes. These include bulbar function, speech, respiratory function, muscle strength, and survival.

The trial has enrolled its first patient in the pridopidine arm. Researchers estimate to complete it in September 2022.

Additional information

Pridopidine also is being assessed in clinical trials for Huntington’s disease. In addition, researchers are investigating the medication in preclinical studies for neurodegenerative eye disease, Parkinson’s disease, Rett syndrome, fragile X syndrome, and Alzheimer’s disease.


Last updated: Feb. 10, 2021


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