Australians living with the most common form of multiple sclerosis (MS) will gain access to a new treatment option with the listing of Zeposia (ozanimod) now on the Pharmaceutical Benefits Scheme (PBS).

Zeposia (ozanimod) is an oral treatment for adult patients with relapsing forms of MS. It is known as a disease-modifying therapy (DMT), which alters immune system activity to help reduce the frequency of attacks to the central nervous system, including the brain, spine and optic nerve.

The PBS listing coincides with the publication of an article in the Medical Journal of Australia's Insight.

Article author Clinical Associate Professor Todd Hardy said treatment for MS must be tailored to the individual, given the highly varying and unpredictable nature of the disease.

"MS affects how the body and brain communicates. The disease causes the immune system to attack the central nervous system, resulting in irreversible scarring on the nerves. This scarring causes messages that travel along the nerves from the brain to the body to be blocked or distorted, compromising physical and cognitive function.

"The symptoms of MS are extremely varied and unpredictable, depending on which part of the central nervous system is affected, and to what degree."

More than 25,600 Australians are currently living with MS, with an estimated 30 new people diagnosed each week.

Common physical symptoms can include fatigue, limb weakness, altered sensations, such as pins and needles or numbness, muscle spasms or tremors, neurological pain, slurred speech, visual disturbances, incontinence, and constipation.

MS can cause cognitive symptoms, including brain fog, slow thinking, and impaired memory and concentration, in addition to personal and emotional changes, anxiety, depression, and difficulties sleeping.