Radicava (Edaravone)

Radicava (edaravone, previously MCI-186) is the first treatment for amyotrophic lateral sclerosis (ALS) that the U.S. Food and Drug Administration (FDA) approved in more than 20 years. An equivalent oral suspension formulation, called Radicava ORS and approved in May 2022, followed the FDA’s 2017 approval of the infusion therapy.

Developed by Mitsubishi Tanabe Pharma, the therapy slows physical function decline in people with ALS. Mitsubishi Tanabe Pharma America is marketing the treatment in the U.S.

The therapy also has been approved in Canada, where it is available under a number of different medication plans, including Veterans Affairs Canada (VAC), Indigenous Services Canada, and several provincial treatment programs.

How does Radicava work?

Radicava is a free-radical scavenger, meaning it helps remove reactive molecules that can cause oxidative stress.

Free radicals are byproducts of normal cellular processes that produce energy. Normally, the body quickly removes them. If they remain in the body, they can cause oxidative stress, leading to damage and cell death.

Researchers think that oxidative stress due to free radicals is one of the causes of nerve cell death in ALS. For example, in some patients with familial ALS, there is a mutation in the gene that encodes for an enzyme, SOD1, which normally removes free radicals. 

Radicava in clinical trials

The FDA’s approval of Radicava, in 2017, was based on the results of a double-blind, randomized, placebo-controlled Phase 3 clinical trial (NCT01492686) that evaluated the therapy’s safety and effectiveness in treating ALS. After a 12-week observation period, the researchers divided the 137 participants into two groups. Those in the first group received 60 mg of Radicava on a specified schedule for six months, while participants in the second group received a placebo. Neither the researchers nor the participants knew which group was receiving Radicava and which the placebo. 

The study’s primary objective was an improvement in participants’ scores on the ALS functional rating scale-revised (ALSFRS-R), a measure of disability progression. Although the rate of progression varies among patients, people with ALS lose an average of one point per month on this scale.

After six months of treatment, those who received Radicava experienced a 33% lower decline in the ALSFRS-R score than those in the placebo group. This was a statistically significant difference, which led researchers to conclude that Radicava significantly reduces the progression of disability in ALS patients.

The results were published in the scientific journal The Lancet Neurology.

The most common side effects, or adverse reactions, from the treatment were walking problems, bruises, and headaches.

Following the trial, Mitsubishi Tanabe Pharma also performed a post hoc analysis on its data. The goal was to investigate differences in ALSFRS-R scores between patients with bulbar-onset and limb-onset ALS. In bulbar onset-ALS, symptoms first appear as problems with speech or swallowing, while in limb-onset, the first manifestations appear as weakness in the arms and legs. A total of 30 study patients had bulbar-onset ALS and 107 had limb-onset.

Researchers also analyzed the data according to differences in patients’ breathing abilities. One group had a forced vital capacity (amount of air that they can exhale) of less than 80% (five patients); the other had viral capacity equal to or above 80% (21 patients). The company recently presented the results of the analysis at the American Association of Neuromuscular & Electrodiagnostic Medicine (AANEM) 2020 Virtual Annual Meeting.

Edaravone, the active ingredient in Radicava, also is being investigated as an oral formulation, called MT-1186, in a Phase 3 open-label clinical trial (NCT04165824). That trial has completed enrollment of about 185 patients at locations in the U.S., Europe, Canada, and Japan. Its primary goal is to investigate the safety and tolerability of the oral version of edaravone at the same treatment pattern as Radicava. The study also will record changes in the ALSFRS-R score over 48 weeks (nearly one year). Finally, it will record the time until death or a major surgical intervention, such as a tracheostomy or permanent mechanical ventilation, is needed to support breathing functions.

Other details

Radicava, as an infusion treatment, is administered into the bloodstream in 28-day cycles. The treatment starts with a patient receiving the therapy for 14 consecutive days, followed by a two-week treatment-free period. Patients then receive a daily infusion over 10 of the next 14 days, followed by a two-week treatment-free period.

The therapy dose is typically 60 mg, and each Radicava infusion takes about 60 minutes to administer.

Radicava ORS, the oral suspension formulation, is designed to offer the same efficacy as infused Radicava, while being more convenient. It follows the same dosing regimen, listed above, as the original formulation.

Radicava ORS comes in a portable bottle, includes a 5 mL oral syringe for accurate dosing, and can be self-administered at home. It should be taken orally or via feeding tube (5 mL/105 mg) in the morning after overnight fasting, and patients are advised to consume nothing but water for one hour after its administration.

It is important that healthcare providers are aware of other medical conditions that patients may have, such as asthma or allergies to other medicines, which could lead to complications. Clinicians also should know if the patient is pregnant or plans to become pregnant, or breastfeeding or planning to breastfeed.


Last updated: Aug. 16, 2022


ALS News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.