Cutting Edge Companies: Cyberonics

By Heidi Vanni, CFA
Portfolio Manager




This column highlights companies in the business of providing solutions to social and environmental challenges. Featured companies are typically held in the Small Cap Innovations portfolios offered to Walden clients.

Convulsions, twitching or jerking muscles, and even loss of consciousness: The characteristics of an epileptic seizure are well-known. A seizure may persist for up to several minutes and can be a difficult episode to endure. Epilepsy is a disorder in which neurons in the brain, the cells responsible for processing and relaying information in the nervous system, are subject to abnormal neurotransmitter levels leading to disturbed neuronal activity. Epilepsy is the fourth most common neurological disease after migraine, stroke, and Alzheimer’s. There are currently nine million people living with epilepsy in the United States, Europe, and Japan. The majority of patients with epilepsy rely primarily on anti-epileptic drugs to manage the disease; however, more than 30 percent of patients continue to experience seizures in spite of multiple pharmacological treatments.

Texas-based Cyberonics has developed a medical device utilizing vagus nerve stimulation (VNS) therapy for the long-term treatment of epilepsy. Cyberonics’ VNS Therapy system received FDA approval in 1997 as an adjunctive therapy for reducing the frequency of seizures. Known as a refractory therapy, VNS Therapy is appropriate for individuals who do not respond to pharmacological treatment.


   Source: Cyberonics, Inc.
The vagus nerve originates in the brainstem and travels down the body through the neck. It is responsible for many key parasympathetic activities including heart rate. VNS Therapy is conducted by implanting a pacemaker device (and associated leads) into the chest. Mild pulses applied to the vagus nerve in the neck send signals to the brain. It is believed that the regular electrical pulses delivered to the vagus nerve assist in regulating neurotransmitter activity in the brain, but the exact mechanism is unknown. The devices provide adjustable, automatic intermittent stimulation. The frequency of electrical impulses is specific to each patient and doctors customize the therapy to achieve optimal seizure reduction.

There is strong clinical evidence in support of VNS Therapy (1,200 publications). In comparison to second-generation anti-epileptic drugs, VNS Therapy has demonstrated similar efficacy with approximately 40 percent of VNS responders experiencing a greater than 50 percent reduction in seizure frequency. Moreover, devices have fewer unwanted side effects than anti-epileptic drugs (though they are obviously more invasive). Perhaps the most powerful argument in favor of these devices is evidenced by the decision patients are making related to “re-implanting” the device. When the battery life of Cyberonics’ device expires (typically after five to seven years), patients choose to re-implant the device approximately 90 percent of the time.

For people with epilepsy, every day can be a challenge. Cyberonics’ VNS Therapy system offers a mechanism to improve seizure control and quality of life without adding a pharmacological burden.

From the Summer 2014 Edition of Values