No miracle cure for cancer suffered by Gord Downie, but research offers hope

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Soon after I wrote about Gord Downie's terminal cancer diagnosis, the e-mails and tweets started. One reader wrote to me about a "revolutionary treatment" at North Carolina's Duke University "where they are actually curing the type of brain cancer Gord has." Another said he was "surprised that no one was talking about this new treatment in connection with Gord's diagnosis." Many others took to Twitter to urge Downie to go to the United States to get the "polio vaccine treatment."

They were referring to a new "breakthrough" treatment for glioblastoma, the deadly cancer the Tragically Hip frontman has, that had been profiled on the show 60 Minutes in 2015 and last month. The program focused on a research team at Duke who are using an engineered version of the polio virus – not the vaccine – to destroy the tumour. The show has generated buzz about a purported cure, especially after host Scott Pelley revealed on the recent show that the U.S. Food and Drug Administration had granted the treatment a "breakthrough therapy designation."

So, is this the beginning of the end of glioblastoma? If only things were that simple.

The background

Glioblastomas are typically treated with surgery to remove as much of the tumour as possible, followed by radiation and chemotherapy. The problem is, cancer cells find their way to other parts of the brain and are very hard to kill. Eventually, the cancer comes back. Median survival is about 14.6 months, according to the American Brain Tumor Association.

Researchers at Duke have been experimenting with an engineered version of the polio virus to destroy the cancer cells by igniting the body's own immune response. It's part of the burgeoning field known as immunotherapy, with researchers around the world testing other engineered viruses to see if they generate a cancer-fighting immune response. Last October, for instance, the FDA approved Imlygic, an engineered version of the herpes virus, for the treatment of the deadly skin cancer melanoma.

In the case of glioblastoma, Duke researchers have discovered that the polio virus breaks open the cancer cells, making them vulnerable to an attack. (The researchers were not available for an interview.) The virus itself also appears to directly kill cancer cells, said David Kroll, a former pharmaceutical sciences professor who is also an unpaid adjunct associate professor of general internal medicine at Duke.

Promises, hope and hype

60 Minutes focused on a handful of patients treated with this new approach. Two of the patients featured were given a clean bill of health after receiving the viral treatment, something that is pretty much unheard of when it comes to glioblastoma. So you might understand why the segment was peppered with words such as "cure" and "miracle."

But how did others fare? One woman didn't respond well to the treatment and died a painful death, saying into a camera from her nursing home bed that she "might not have done" the treatment if she could choose again.

The focal point of the segment, however, was the story of Nancy Justice, a wife and mother in her late 50s. After being treated, her tumour shrank in size and she appeared to thrive. But during last month's broadcast, it was revealed that Justice had suffered several setbacks. The cancer resumed growing, and there were eventually no options left. She died on April 6. The researchers said, however, that she lived nine months longer than she would have otherwise.

Defining a "breakthrough"

Nine months may not seem that much, but when you are dealing with one of the most aggressive, deadly forms of cancer, it's a remarkable achievement.

Still, it's premature to brand this polio-based treatment as a miracle or even a cure.

The FDA did grant the viral therapy breakthrough status, but that doesn't mean it's a surefire therapy that can be used on all patients. It means the treatment appears to offer a significant improvement compared with other options and that the FDA will "expedite the development and review" of the drug to figure out how well it works, what the risks are and who could benefit.

"This is an experimental treatment for an incredibly devastating tumour of the brain," Kroll said. "Anything that can make baby steps in the direction of giving people longer, better quality months and even years is certainly something you'd want to pursue."

The problem is that focusing too much on the two patients cured by the polio therapy may convey false hope about how well the treatment works in the general population. While some patients receiving polio therapy appear to improve, others do not.

Kroll also noted that only a small fraction of glioblastoma patients will likely be accepted into research trials looking into this therapy. Many people won't be eligible because of the location of the tumours in their brains, for instance.

Other advancements

The researchers at Duke aren't the only ones on the hunt for better glioblastoma treatments. In fact, Downie's hometown of Kingston, Ont., is home to a group of leading researchers studying this devastating disease.

Earlier this month, a Queen's University researcher presented important results from a new study that he believes will change how the disease is treated in older people. Until now, treatment options for patients 65 and older have been limited, as few studies have looked at whether that age group responds to chemotherapy. It's also well-known that radiation often causes cognitive side effects in seniors, so their overall survival rates aren't as long as those of other patients. But Chris O'Callaghan, a senior investigator with the Canadian Cancer Trials Group at Queen's, and his colleagues discovered that when seniors are given a chemotherapy drug and a reduced dose of radiation, their survival improves. Overall, they went from living an average of 7-1/2 months on radiation alone to 13- 1/2 months with the addition of chemotherapy.

"We think this is a new standard," O'Callaghan said.

What lies ahead

That's not to say there isn't reason to be excited about the possibilities of the polio virus therapy. But there is still a long road to travel, with many unanswered questions about the risks and the types of patients who will benefit. Many people consider a treatment a breakthrough only if it cures. But to patients, family members and researchers studying this disease, a drug that can provide even a few extra months of life to someone with this devastating disease would be a remarkable step forward.