By: Thanesha Graham, PharmD Candidate c/o 2019

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Amyotrophic lateral sclerosis (ALS) is commonly referred to as Lou Gehrig’s disease. Gehrig was an American first baseman who played 17 seasons in Major League Baseball for the New York Yankees and passed away from ALS at the age of 37. According to the Centers for Disease Control and Prevention, approximately 12,000-15,000 Americans have ALS, a rare paralyzing disease.¹ ALS destroys the nerve cells that control voluntary muscles responsible for chewing, walking, breathing and talking.¹ Individuals with ALS struggle with these normal bodily functions because their nerves lose the ability to activate specific muscles.¹ These inactivated muscles become weak and soon after, paralyzed. ALS is a progressive disease with a grim prognosis because individuals become worse overtime.  Eventually, people who suffer from Lou Gehrig’s disease die from respiratory failure three to five years from the first onset of symptoms.1 The mean age of onset is 56 years in individuals with no known family history and 46 years in individuals with more than one affected family member.² Genetic testing plays a large role in the diagnosis of this disease because ALS can be inherited through a variety of ways including autosomal dominant, autosomal recessive, or X-linked genes.

Edaravone (Radicava™) is the first new drug approved by the FDA to treat ALS in 20 years.¹ Edaravone was initially widely used in Japan under the name Radicut® marketed by Mitsubishi Tanabe Pharma Corporation. After the United States worked with the Japanese drug developer and filed a marketing application, the treatment became available for use in the States.¹ Edaravone is an intravenous infusion that must be administered by a health care professional.¹ This drug is accompanied by a very specific dosing schedule, with an initial treatment cycle of daily dosing for 14 days, followed by a 14-day drug-free period and further cycles of dosing for 10-14 days followed by another 14 days drug-free.¹ Edaravone was proven to be efficacious after a six-month clinical trial in Japan called “Study of MCI- 186 for Treatment of Amyotrophic Lateral Sclerosis in Japan”.¹ After 24 weeks of treatment, individuals who received the drug declined less than those receiving placebo.¹ The adverse reactions observed with Radicava were bruising and gait disturbances.¹ There were also some serious risks associated with the drug requiring immediate care which included hives, swelling, shortness of breath, and allergic reactions to an ingredient in the drug, sodium bisulfite.¹ Although the drug has substantial benefits, it may not be a perfect fit for all ALS patients, due to the risks and adverse effects. In fact, sodium bisulfite may cause anaphylactic symptoms that are life threatening and possibly fatal.¹

Before edaravone, riluzole (Rilutek®) was the only other FDA-approved drug for ALS. Two other drugs such as tricyclic antidepressants and anti-cholinergics are used to reduce oral secretions in certain patients.² These drugs are used because patients with bulbar-type symptoms, named after the corticobulbar neurons affected by ALS, experience dysarthria and dysphagia.² Additionally, baclofen and benzodiazepines are used to relieve spasms and muscle cramps.² Edaravone works uniquely by reducing oxidative stress, one of the factors that contributes to the onset and progression of the disease. Patients with ALS show increases in oxidative stress biomarkers, which serves as a useful target for novel ALS drugs.³ Oxidative stress is the imbalance between the production of free radicals and the ability of the body to counteract or detoxify their harmful effects.³

Although treatment for Lou Gehrig’s disease is palliative, drugs such as edaravone help manage its life-altering symptoms. The development of this drug is a major step in finding stronger, more effective drug therapies for this fatal disease.

SOURCES:

1. Walsh S. FDA approves drug to treat ALS. U.S. Food and Drug Administration. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm557102.htm. Published 05/05/2017. Last Updated 05/08/2017.
2. Kinsley L, Siddique T. Amyotrophic Lateral Sclerosis Overview. In: Pagon RA, Adam MP, Ardinger HH, Wallace SE, Amemiya A, Bean LJH, Bird TD, Ledbetter N, Mefford HC, Smith RJH, Stephens K, editors. GeneReviews ® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2017. Published 03/23/2001.Updated 02/12/2015.
3. Drug and Device News. Pharmacy and Therapeutics. 2016;41(10):606-614.

Published by Rho Chi Post