A commonly used antiviral drug that's already used to fight hepatitis C and HIV could also be used to treat 30 per cent of cancer types, according to a new study conducted on patients in Canada.
Doctors in Montreal tested the antiviral drug ribavirin on 11 patients with acute myeloid leukemia (AML), who had undergone several other treatments that had previously failed.
Nine of the patients saw their conditions improve within a matter of months, with one achieving complete remission and two achieving partial remission, all with few side effects. The results are published online in the journal, Blood.
Frank Klamph was one of the patients who benefitted from the treatment. Last fall, he was weak and ill with AML. After taking part in the study to test the experimental treatment, he achieved complete remission and was even able to leave hospital and scuba dive in Florida.
"Within two short months, it was like a miracle," he told Â鶹´«Ã½. "I feel like the cancer is gone."
The researchers, led by Dr. Katherine Borden, at the Institute for Research in Immunology and Cancer (IRIC) of the Universit� de Montr�al, say that ribavirin works by suppressing activity of the eIF4E gene, which becomes overactive in 30 per cent of cancer types and overproduces a protein that helps turn cells cancerous.
"In several of the patients, we had remissions -- which is completely unheard of for these kinds of patients. And in another subgroup of patients, we had really dramatic drops in the number of leukemia cells they had, including patients where we could no longer or barely detect any leukemia in them anymore," Borden explained.
"To have patients who feel good and can go out and have a life, and not be in hospital sick all the time, which is often the normal course of leukemia, that was really exciting for us and that's why we're excited."
Dr. Brian Leber, one of the other IRIC investigators involved in the study, says what makes the results so exciting for him is that ribavirin is an already established drug.
"This has been obtained with a drug that has been available for probably a decade," he said. "So unlike a lot of extremely promising cancer therapies that are in earlier stages of development, this is a drug that we could use immediately.
Leber was also pleasantly surprised by how quickly the treatments seemed to have an effect on patients.
"This type of response rate in a wide variety of patients, who have pretty advanced leukemia, would be considered pretty remarkable for any drug," he said.
"Certainly, considering how well it was tolerated and the fact that it's a very convenient oral therapy that can be taken at home, when you put all this into the mix I think it is quite exciting results."
Dr. Borden says ribavirin is likely to show promise for other types of cancer associated with dysregulation of the eIF4E gene.
She says the next challenge is to combine the promising antiviral with chemotherapy, to improve its effectiveness.
She says they also need to work on ways to combat the development of resistance to the drug.
With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip
