Saskatchewan is the third province in Canada to fully fund a new multiple sclerosis drug under the provincial drug plan, according to the Saskatchewan branch of the Multiple Sclerosis Society of Canada (MSSC).

The drug is called Ocrevus. It's typically delivered by IV every six months into patients with two of the four types of multiple sclerosis (MS): primary progressive MS and relapsing remitting MS.

It's the first ever drug approved by Health Canada to treat the primary progressive type of MS, which is the most aggressive form of the disease.Ocrevus is listed as covered by Quebec and Alberta's drug plans.

MS is an unpredictable and debilitating autoimmune disease that affects the brain, spinal cord and optic nerves. The drug targets a protein that is found in white blood cells in an effort to block the inflammation that drives the disease, according to the MSSC.

Jessica MacPherson, director of government relations and communications for the MSSC's Saskatchewan branch, said life with primary progressive MS varies from person to person, but told CBC what that diagnosis could entail.

"Maybe the loss of their mobility, it could have serious impacts on cognitive function and really on the quality of life that they live. Without any effective treatment for that, it's a process where people, their entire lives as they know it often change," MacPherson said.

Ocrevus is only prescribed for the early subset of primary progressive, which means only a small portion of the population is eligible to use it, she said.

Still, the MS society got a warm response when it put out a call for public feedback in late 2017, before the drug was approved federally.

"It helps to offer hope. It shows that things are moving forward and really allows people to know that they can expect greater advancement in years to come," MacPherson said.

The drug offers a treatment option that could slow down the progression of the disease and improve the quality of life for people with it, Jim Reiter, Saskatchewan's health minister, said in a statement.

"Our government is committed to providing Saskatchewan residents with better access to innovative new treatment options," he said.

MacPherson said the announcement is welcome news in a world where medication can be pricey.

Ocrevus reduces the number of treatments that people with relapsing remitting MS — the most common type — have to get. After two initial doses of Ocrevus, patients only need to do one IV treatment every six months.

According to the company's website, other common treatments require doses of at least a pill per day, three injections per week or one IV treatment every four weeks.

The side effects of the drug can be serious. They include severe skin reactions, depression, feelings of self harm and suicide, respiratory and other infections and depression, according to the MSSC.

The feedback the MS society received from patients acknowledged that Ocrevus is not without its risks, MacPherson said.

"Even if there are side effects to taking medications, people still want to be able to have the choice. And that's important that they have the choice to access something that might improve their lives," she said.

There are around 3,700 people in Saskatchewan who have been diagnosed with MS.