Canadians affected by Huntington's disease are cautiously celebrating a breakthrough trial of a drug that safely lowers levels of the harmful huntingtin protein.

Bev Heim-Myers, CEO of the Huntington Society of Canada, said trials in B.C., Germany and the U.K. showed the drug IONIS-HTTRx safely tackles the protein that causes the fatal disease.

"For a long time, we've known what to do, and that is lower the Huntington mutation, but this study has actually proven that we can lower it. That's a very exciting step," she told CBC News Wednesday.

Drug passes Phase 1 trial

The society says people are born with the neurodegenerative illness that has physical, cognitive and emotional symptoms. A genetic mutation makes the protein huntingtin, which eventually causes parts of the brain to die.

People who have it usually start showing symptoms in their 30s to 50s. Heim-Myers said it finally steals people's ability to think and talk.

"It's devastating. From the time a person starts to show symptoms, it can take ten to 15 years for them to die from the impact of the disease."

Bev Heim-Myers said the disease blights families, who now have new reasons for hope. (Huntingtonsociety.ca)

On Monday, researchers at the University College London announced the drug has made it through Phase 1 of the clinical trial. Some 46 patients with early Huntington's disease participated in the study. Dr. Sarah Tabrizi of UCL's Huntington's Disease Centre said they will next run a larger trial to see if the drug slows the disease's progression.

Heim-Myer said that could happen in 2018.

She said it's hard to forecast beyond that, but if all continues to go well, the drug could be widely available in five years. Health Canada has already approved the drug for the clinical trial, which would expedite getting it to the wider public should tests continue to show the drug works.

"Because it's a genetic disease, it impacts generations of the family. There are young people who have seen their grandparent die from this disease; they're now being a loving caregiver with their parent, and dealing with their own risk, and their children's risk. It's devastating and news like this is incredibly promising for this community," she said.

"It's a good time in the history of this disease because we have a lot of hope."

'I am at risk'

In Halifax, Brittany Carmichael greeted the news with restrained hope. Her father Steven started developing symptoms of Huntington's disease when he was about 30; she was two. When she was five, he had to stop working. When she was six, he had to stop driving. When she was 24, he died.

"He was sick most of my life. He moved into long-term care when I was 12 or 13," she said. "It's been a huge part of my life."

Children of people who have the disease face a 50-50 chance of having it themselves.

"I am at risk. I haven't been tested for the gene myself. My brother is also at risk as well."

Carmichael said she and her brother are excited, but cautious. Some media reports made it sound like a cure, she said.

"We're really hopeful it's going to be something that is going to possibly treat Huntington's in the future," she told CBC News.

"We do know there's a long ways to go before we can really celebrate the end of Huntington's disease. We've been dealing and praying for so long. My father's hope was always so strong in a treatment or some sort of help. He's always been hopeful and we're hopeful and we're continuing to hope that this is going to turn into something really tangible."

One day at a time

Carmichael said it's the most significant breakthrough since American geneticist Nancy Wexler found the gene that causes the disease in 1993.

The Carmichaels have found "a sense of peace" about living with Huntington's.

"Our philosophy has always been one day at a time. No future is guaranteed, even in lives that aren't affected by Huntington's disease. So if today is a good day and we're healthy and we're happy, and we're together, then we enjoy this moment," she said.

"We take on tomorrow once it's here. That's how my father lived his life and that's how my brother and I live ours."

Meanwhile, she recently finished her bachelor's degree in psychology and has applied to do a master's degree in social work.

"This is lighting a real fire under everyone to do fundraising and getting things organized in their own lives like testing, talking about it with their family. Because it's sort of on a high note now, rather than a dark one. It's an encouraging time altogether."