PeptideCompareEdaravone — EU research guide.
Edaravone is a synthetic pyrazolone free-radical scavenger approved as a medicine for ALS in the United States (and, reportedly, Japan) and for acute ischemic stroke in Japan. Its EU marketing application was withdrawn in 2019.
What is Edaravone?
Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one, also known as MCI-186) is a synthetic pyrazolone developed by Mitsubishi Tanabe Pharma. It is an approved medicine in Japan (acute ischemic stroke 2001, as Radicut; ALS reportedly 2015) and in the United States (ALS: intravenous form 2017, oral suspension 2022, as Radicava). It is described as a free-radical scavenger that may reduce oxidative damage to neurons; the FDA label states that the exact mechanism of its effect in ALS is not known. These approvals cover the licensed products only. A research vial from a vendor is not the licensed medicine.
What does the research show?
The main ALS evidence is one positive phase 3 trial in a narrowly selected group. In MCI186-19 (Japan, 24 weeks) 137 patients were randomised (69 edaravone, 68 placebo) and 134 were analysed. The ALSFRS-R score fell by 5.01 points on edaravone and 7.50 on placebo, a difference of 2.49 points (95% CI 0.99 to 3.98; p=0.0013). An earlier Japanese phase 3 study (MCI186-16) did not meet its primary endpoint, and a study in more advanced (grade 3) ALS (MCI186-18, about 25 patients according to a secondary source) showed no effect on ALSFRS-R. For acute ischemic stroke, the pivotal Japanese trial reported a modified Rankin Scale benefit (p=0.0382), mainly in patients treated within 24 hours, according to a 2010 critical review. Efficacy in ALS beyond the selected trial population is debated.
EU legal status
Not authorised in the EU. Mitsubishi Tanabe Pharma GmbH withdrew its centralised marketing authorisation application for Radicava (edaravone) in ALS on 24 May 2019, after the CHMP's provisional view that the benefits did not outweigh the risks. EMA's Q&A cites concerns including the small main study (137 patients), the 24-week duration, baseline imbalances favouring the treatment group and unclear long-term benefit. Approved medicines exist in the US and Japan. Edaravone was not found in a copy of the 2026 WADA Prohibited List; this was read with a page-reading tool, not by a manual search. Some secondary sources mention an EU orphan designation, which is not an authorisation.
Molecular information
Pharmacokinetics
Potency retained over time
Each line is one storage condition: it starts at 100% and falls as potency is lost. Above the dashed 80% line the material is considered reliable — hover for exact values.
⚠ Modelled per compound from molecular structure — chain length, cyclisation, oxidation- and deamidation-prone residues and light sensitivity. Indicative only, not lab-measured per batch.
Edaravone across EU suppliers
COA-verified EU vendors · Updated monthly
References
- Phase 3 trial MCI186-19: 137 randomised, 134 analysed, ALSFRS-R change of -5.01 vs -7.50 (difference 2.49; 95% CI 0.99 to 3.98; p=0.0013) and adverse-event data. Writing Group on behalf of the Edaravone (MCI-186) ALS 19 Study Group. Safety and efficacy of edaravone in well defined patients with amyotrophic lateral sclerosis: a randomised, double-blind, placebo-controlled trial. Lancet Neurol 2017. DOIPubMed 28522181
- Earlier phase 3 study (MCI186-16) that did not meet its primary endpoint; the title is confirmed, but the abstract was not read. Confirmatory double-blind, parallel-group, placebo-controlled study of efficacy and safety of edaravone (MCI-186) in amyotrophic lateral sclerosis patients (study MCI186-16). Amyotroph Lateral Scler Frontotemporal Degener 2014. DOI
- US prescribing information: formula, molecular weight, half-life, adverse reactions, hypersensitivity and sulfite warnings, and US approval history (2017; oral suspension 2022). RADICAVA (edaravone injection) and RADICAVA ORS (edaravone oral suspension) prescribing information. US FDA, revised 2022. Source
- EMA questions and answers on the withdrawal of the EU application on 24 May 2019 and the CHMP's concerns. Questions and answers on the withdrawal of the marketing authorisation application for Radicava (edaravone). European Medicines Agency, 2019. Source
- Critical review of the edaravone stroke trials, including the 2001 Japanese approval (Radicut), the pivotal trial result and the free-radical scavenger mechanism. Lapchak PA. A critical assessment of edaravone acute ischemic stroke efficacy trials: is edaravone an effective neuroprotective therapy? Expert Opin Pharmacother 2010. DOIPubMed 20491547
- Independent overview: MCI186-19 results, MCI186-16 and MCI186-17 missing their primary endpoints, MCI186-18 in grade 3 ALS without effect, and common adverse effects. Edaravone for amyotrophic lateral sclerosis. Aust Prescr 2025. DOI