• Researchers at the Bionics Institute are developing an innovative, drug-free treatment for rheumatoid arthritis.
  • The treatment uses an electrical medical device to target the nervous system and trigger the body’s natural anti-inflammatory response.
  • This new treatment will help the large number of people with rheumatoid arthritis who do not respond to available treatments and suffer from ongoing pain and disability.

What is rheumatoid arthritis?

Rheumatoid arthritis is a chronic and debilitating condition that affects over 20 million people worldwide, including almost 500,000 Australians.

It can affect people of all ages but is more common between the ages of 30 and 50 years. Unlike osteoarthritis, which is caused by wear and tear, rheumatoid arthritis is an auto-immune disease.

It occurs when the body’s immune system attacks its own tissues, causing widespread damage to the lining of joints and painful swelling.

In severe cases it can lead to bone erosion and joint deformity, causing physical disabilities. Treatment includes immunosuppressant drugs that cause a range of side effects. In some cases, joint reconstruction surgery is required.

The issue with existing treatments

Currently there is no cure for rheumatoid arthritis. Although a range of drug treatments are available, they can cause unpleasant side effects, including fatigue, nausea, fainting and an impaired immune system.

To compound this issue, 40% of patients with rheumatoid arthritis don’t respond to treatment and continue to live with debilitating symptoms.

Treating rheumatoid arthritis with electricity

Electrical medical devices can be used to alter the activity of nerves to treat a wide range of diseases that don’t respond to drug treatments.

At the core of this ‘electric medicine’ research lies the vagus nerve, which has been harnessed extensively to treat epilepsy and depression.

Recently, researchers at the Bionics Institute invented a vagus nerve stimulation device to treat inflammatory bowel disease and this is now being adapted for use in rheumatoid arthritis.

Harnessing the vagus nerve

The vagus nerve, which runs from the brain to the gut with branches to almost every organ, including the heart, lungs, liver and pancreas, controls many processes in the body.

One of those processes is the body’s immune response. If the vagus nerve detects inflammation in the body, it transmits a signal to start an anti-inflammatory reflex response.

Bionics Institute researchers have found a way to stimulate the vagus nerve using a complex electrical medical device.

This stimulation activates an anti-inflammatory response in the body to suppress damaging inflammation in auto-immune diseases like rheumatoid arthritis.

What sets this treatment apart from the rest?

The beauty of this device is that it kick-starts the body’s natural mechanisms, which means it causes less side effects than drug treatments.

In addition, while other medical devices for rheumatoid arthritis, currently in clinical trials, are inserted at the neck level, the Bionics Institute has developed a device that can be inserted in the abdominal cavity.

This means that the heart and lungs are not adversely affected when the device is switched on.

Next steps for Bionics Institute researchers

Currently in the early stages of development, this device will eventually be implanted into people with drug-resistant rheumatoid arthritis using key-hole surgery.

The aim is to switch on stimulation on as needed to dampen down the body’s overactive immune response and prevent long-term damage to joints.

The vagus nerve stimulation device developed to treat inflammatory bowel disease has passed safety tests for use in humans and will be moving into clinical trials in 2021.

As the rheumatoid arthritis device uses the same therapeutic stimulation strategy, this approval for use in clinical trials will accelerate its development.

Our next steps are to consolidate preclinical data and start planning for a clinical trial with our clinical collaborator, Dr Evange Romas.

The research team

BI researchers: Dr Sophie Payne (PI), Associate Professor James Fallon (PI)

Clinical collaborator: Associate Professor Evange Romas (St. Vincent’s Hospital)

More information for researchers

Despite advances in pharmacological drug therapies, 40% of rheumatoid arthritis patients fail to respond to first order therapy, and 30% of those fail second order therapy (Bystrom et al., 2017).

Applying stimulation to the abdominal vagus nerve overcomes the two major limitations encountered during cervical stimulation. At the abdominal level, the vagus is closer to the spleen, consists of 99% C-fibres (Hoffman and Schnitzlein, 1961) and is distal to vagal branches that innervate the heart and lungs, resulting in no off-target effects to breathing and heart rate during stimulation (Payne et al., 2019).

A human version of the abdominal vagus nerve device is entering clinical trials for the treatment of inflammatory bowel disease later this year (2021, Austin Hospital). As such, if abdominal stimulation proves an effective treatment of experimental arthritis, the treatment will be translated into the clinic quickly with the support of the team’s clinical collaborator, rheumatologist, Associate Professor Evange Romas.

Publications

Payne et al., 2018 Nat Rev: Gastrol & Hep https://doi.org/10.1038/s41575-018-0078-6
Payne et al., 2019 Frontiers in Science. http://doi.org/10.3389/fnins.2019.00418