Edaravone, sold under the brand name Radicava among others, is a

medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...

used to treat stroke and

amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or Lou Gehrig's disease, is a neurodegenerative disease that results in the progressive loss of motor neurons that control voluntary muscles. ALS is the most comm ...

(ALS). It is given by

intravenous infusion Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...

and

by mouth Oral administration is a route of administration where a substance is taken through the mouth. Per os abbreviated to P.O. is sometimes used as a direction for medication to be taken orally. Many medications are taken orally because they are i ...

. The most common side effects include bruising (contusions), problems walking (gait disturbances), and headaches. The mechanism by which edaravone might be effective is unknown. The medication is known to be an antioxidant, and

oxidative stress Oxidative stress reflects an imbalance between the systemic manifestation of reactive oxygen species and a biological system's ability to readily Detoxification, detoxify the reactive intermediates or to repair the resulting damage. Disturbances ...

has been hypothesized to be part of the process that kills neurons in people with ALS. The U.S.

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA) considers it to be a

first-in-class medication A first-in-class medication is a pharmaceutical that uses a "new and unique mechanism of action" to treat a particular medical condition. While the Food and Drug Administration's Center for Drug Evaluation and Research tracks first-in-class medicat ...

Medical uses

Edaravone is used to help people recover from stroke in Japan, and is used to treat ALS in the US and Japan.

Adverse effects

The label carries a warning about the potential for hypersensitivity reactions to edaravone, and adverse effects include bruising, gait disturbances, headache, skin inflammation, eczema, problems breathing, excess sugar in urine, and fungal skin infections. The following adverse effects in at least 2% more people given the medication than were given placebo: bruising, gait disturbances, headache, skin inflammation, eczema, problems breathing, excess sugar in urine, and fungal skin infections. There is no data on whether it is safe for pregnant women to take, and it is unknown if edaravone is secreted in breast milk.

Pharmacology

The mechanism by which edaravone might be effective in ALS is unknown. The medication is known to be an antioxidant, and oxidative stress has been hypothesized to be part of the process that kills neurons in people with ALS. The half-life of edaravone is 4.5 to 6 hours and the half-lives of its metabolites are 2 to 3 hours. It is metabolized to a sulfate conjugate and a

glucuronide A glucuronide, also known as glucuronoside, is any substance produced by linking glucuronic acid to another substance via a glycosidic bond. The glucuronides belong to the glycosides. Glucuronidation, the conversion of chemical compounds to glucur ...

conjugate, neither of which are active. It is primarily excreted in urine as the glucuronide conjugate form.

History

Researchers first developed the free radical scavenger edaravone in late 1980s as a treatment for stroke. The approach, introduced by Koji Abe, now at Okayama University Hospital in Japan, aimed to prevent the swelling of the brain which may occur after a stroke. It has been marketed in Japan by

Mitsubishi Pharma Mitsubishi Tanabe Pharma Corporation is a Japanese pharmaceuticals company from Osaka, a subsidiary of Mitsubishi Chemical Holdings Corporation. was formed in 2001 from the merger of Mitsubishi-Tokyo Pharmaceuticals and Welfide Corporation. On ...

for stroke since 2001 and is now generic. Mitsubishi Tanabe started a phase III clinical trial in ALS in 2011, in Japan, and by June 2015, it had been approved for that use in Japan. The company had received Orphan Drug Designation for edaravone from the FDA and EU by 2016. It was approved for ALS in the US in 2017, based on a small randomized controlled clinical trial with people who had early-stage ALS in Japan, who were administered the medication for 6 months; it had failed two earlier trials in people with all stages of ALS. In May 2017, I.V. edaravone was approved by the FDA to treat people with

(ALS) in the United States. The FDA approval was conditioned on Mitsubishi Tanabe completing several additional studies to clarify the risks of cancer and liver disease, among other effects of the medication. Formulation of edaravone by mouth called TW001 (mixture of the edaravone and SBE-HP-βCD ) has been under development by Treeway for ALS; as of 2015, it had successfully completed Phase I trial and had received orphan status in the US and in the European Union. An oral formulation of edaravone was approved for medical use in the United States in May 2022. The effectiveness of oral edaravone is based on a study that showed comparable levels of oral edaravone in the bloodstream to the levels from the IV formulation of edaravone. The efficacy of edaravone for the treatment of ALS was previously demonstrated in a six-month clinical trial that served as the basis for approval in 2017. In that trial, 137 participants were randomized to receive edaravone or placebo. At week 24, individuals receiving edaravone declined less on a clinical assessment of daily functioning compared to those receiving placebo. An analysis of real-world data of 194 patients from 12 ALS clinics, failed to reproduce the effect.

Society and culture

Economics

The price for the medication when it launched in Japan for stroke in 2001, was set by the Japanese government at 9,931 yen/ampule. When the medication launched in Japan for ALS in 2001, the price was $35,000; the price in Japan in 2017 was $5,000, the US price at launch was around $145,000. In the US the medication was approved for all people with ALS but it was unclear at approval whether insurers would agree to pay for the medication for all people with ALS, or only people in the early stages of the disease. There are three filed trials for edaravone, demonstrating it may work in less than 5% of all ALS population.

Brand names

Brand names include Radicut, ラジカット, Radicava, Xavron.

References

External links

* {{Portal bar , Medicine Antioxidants Pyrazolones Lactams Neuroprotective agents Nootropics Orphan drugs