| Manufacturer || Mitsubishi Tanabe
| Disease || ALS
| Indication || ALS
| Mode of Action || Radical scavenger
| Approval Status || FDA approved (USA); PMDA approved (JAP)
| CAS Number || 89-25-8
| HS Code || 29331990
| Strength || 30 mg / 20 mL (vials), 30 mg / 100 mL (infusion bags)
Who is edaravone for?
Edaravone is indicated for:
- Patients with amyotrophic lateral sclerosis (ALS) .
- Patients affected by neurological symptoms, disorder of activities of daily living, and functional disorder associated with acute ischaemic stroke .
Edaravone is approved in Japan under the name Radicut for both indications 
and in the USA under the name Radicava for the treatment of ALS 
. Radicava and Radicut contain the same active ingredient edaravone.
Complete information about edaravone dosage and administration can be found here for Radicut: 
(an unofficial translation can be found here: 
); and here for Radicava: .
The standard dosage for adult patients affected by disorders associated with ischaemic stroke
- 30 mg of edaravone diluted with an appropriate volume of physiological saline, etc., which is administered intravenously over 30 minutes twice a day in the morning and the evening.
- Administration of this product should be initiated within 24 hours after the onset of the disease, and the duration of administration should be within 14 days.
The standard dosage for adult patients with ALS
- 60 mg of edaravone administered intravenously over 60 minutes once a day.
- First cycle: daily dosing for 14 days followed by a 14-day drug-free period
- Subsequent treatment cycles: daily dosing for 10 days out of 14-day periods, followed by 14-day drug-free periods.
Radicut, distributed by MT Pharma Japan, is supplied in two formats:
- Single-dose infusion bags containing 30 mg / 100 mL clear, colorless, sterile solution. The infusion bags are ready for use. No dilution is required. Two infusion bags are needed for one infusion.
- Single-dose vials containing 30 mg / 20 mL clear, colorless, sterile solution. Before the infusion, it should be diluted with an appropriate volume of physiological saline. Two vials are needed for one infusion .
Radicava, distributed by MT Pharma America, Inc, is supplied in single-dose polypropylene bags containing 30 mg / 100 mL clear, colourless, sterile solution for intravenous infusion (no dilution needed). Each 60 mg dose should be administered as two consecutive 30 mg intravenous infusion bags over a total of 60 minutes (infusion rate approximately 1 mg per minute ) 
What is edaravone and how does it work?
Edaravone is a radical scavenger used to treat patients with ALS 
or ischaemic stroke 
Free radicals such as hydroxyl radical (-OH) play a major causative role in the development of cerebral vascular disorder resulting from ischaemia. During ischaemia or ischaemic reperfusion, the production of free radicals increases which leads to cell membrane injury and ultimately to cerebral dysfunction 
Although the etiology of development and disease progress of amyotrophic lateral sclerosis (ALS) are unknown, a possible involvement of oxidative stress caused by free radicals is suggested 
The mechanism by which edaravone exerts its therapeutic effect in patients with ALS is unknown 
. It is expected that edaravone scavenges free radicals and prevents oxidative damage to brain cells (vascular endothelial cells/nerve cells). In the case of amyotrophic lateral sclerosis (ALS), this product is expected to suppress the disease progression by exerting its inhibitory effects against the development of oxidative damage to nerve cells 
What is edaravone's approval status?
Edaravone was approved by:
- PMDA (JAP) as Radicut:
- in June 2001 for acute ischemic stroke .
- in June 2015 for the treatment of ALS .
- FDA (USA) on May 5, 2017, as Radicava for the treatment of ALS .
The approval for the treatment of ALS was based on a study (MCI186-19) which compared the effect of edaravone with placebo on 137 ALS patients (69 patients on edaravone; 68 patients on placebo). The study consisted of 6 cycles. The comparison was based on the changes in the ALSFRS-R scores before and after the treatment. The ALSFRS-R scale consists of 12 questions that evaluate the fine motor, gross motor, bulbar, and respiratory function of patients with ALS in activities as speech, salivation, swallowing, handwriting, cutting food, dressing/hygiene, turning in bed, walking, climbing stairs, dyspnea, orthopnea, and respiratory insufficiency. Each item is scored from 0-4, with higher scores representing greater functional ability 
. Although rates of ALS progression can vary significantly, research shows that people with ALS lose an average of one point per month on the ALSFRS-R scale 
. The patients selected for the study had ALSFRS-R scores of minimum 2 on all 12 items; normal respiratory function (defined as percent-predicted forced vital capacity values of [%FVC] ≥80%); disease duration of maximum 2 years. The majority of patients (90%) in both groups were treated during the course of the study with another medicine named riluzole 
The decline in ALSFRS-R scores from baseline after 24 weeks was significantly less in the edaravone-treated patients (Mean ± Standard Error (95% CI) = - 5.01 ± 0.64) as compared to placebo (Mean ± Standard Error (95% CI) = - 7.50 ± 0.66) with a difference between edaravone and placebo on the ALSFRS-R scale of 2.49 (95 % CI = 0.99, 3.98) 
. This corresponds to a 33 % difference between the two groups 
As it is the case with every medicine, the effect of edaravone, although on average superior to placebo, was not the same for all patients. The distribution of change in ALSFRS-R scores from baseline to Week 24 by percent of patients can be found here: 
Additional results can be found here: 
The most common adverse reactions reported by clinical trial participants receiving edaravone were bruising (contusion) and gait disturbance. It is also associated with serious risks that require immediate medical care, such as hives, swelling, or shortness of breath, and allergic reactions to sodium bisulfite, an ingredient in the drug 
In December 2014, edaravone was granted orphan designation by the European Commission for the treatment of ALS 
. The European Medicine Agency (EMA) granted the orphan designation 
based on the following expected mechanism of action:
"Damage to nerve cells in ALS appears to have several causes but there is evidence that it may involve damage to nerves caused by toxic molecules containing oxygen. In some patients, this is associated with a defect in the gene responsible for producing the enzyme called superoxide dismutase (SOD), which causes the enzyme to clump together inside nerve cells. This leads to inflammation and kills the affected nerve cells. Edaravone is expected to act as an antioxidant, a molecule that can prevent damage to nerve cells caused by oxygen-containing molecules, and also blocks the clumping together of SOD in the nerves and so reduces inflammation..."
Summary of Product Characteristics [PMDA]: Radicut (edaravone), Mitsubishi Tanabe Pharma Corporation, June 2015. http://www.pmda.go.jp/PmdaSearch/iyakuDetail/ResultDataSetPDF/400315_1190401A1023_3_07
MT Pharma Press Release. MT Pharma Co. receives approval for additional indication for ALS in Japan. 26/06/2015. http://www.mt-pharma.co.jp/e/release/nr/2015/pdf/e_MTPC150626_2.pdf
Abe K., et al. Confirmatory double-blind, parallel-group, placebo-controlled study of efficacy and safety of edaravone (MCI-186) in amyotrophic lateral sclerosis patients. Amyotroph Lateral Scler Frontotemporal Degener. 2014 Dec; 15(7–8):610–7 https://www.ncbi.nlm.nih.gov/pubmed/25286015
Yoshino H. and Kimura A. Investigation of the therapeutic effects of edaravone, a free radical scavenger, on amyotrophic lateral sclerosis (Phase II study). Amyotroph Lateral Scler. 2006 Dec.; 7(4):241–5. https://www.ncbi.nlm.nih.gov/pubmed/17127563
EMA. Public summary of opinion on orphan designation. 23/02/2015. http://www.ema.europa.eu/docs/en_GB/document_library/Orphan_designation/2015/02/WC500183226.pdf
EMA. Orphan Designation. Cited on Jun. 2016. http://www.ema.europa.eu/ema/index.jsp?curl=pages/regulation/general/general_content_000029.jsp&mid=WC0b01ac05800240ce
FDA News Release: FDA approves drug to treat ALS, 05/05/2017. https://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm557102.htm
Summary of Product Characteristics [FDA]: Radicava (edaravone), MT Pharma America Inc., May 2017. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/209176lbl.pdf
Multivu.com. What is Radicava (edaravone)? Cited on May 2017. https://www.multivu.com/players/English/8047051-mt-pharma-america-radicava-fda-approval/docs/radicavaproductfs-1494020153658-192439555.pdf
Summary of Product Characteristics [Unofficial translation]: Radicut (edaravone), Jun. 2015. http://www.e-search.ne.jp/~jpr/PDF/MT18.PDF