Their results, published in the Lancet journal, showed that those who were given the drug rather than a placebo had an average of seven lesions, or damaged sites, compared with 12 in those given a placebo.
There was no significant difference in the overall size of the damaged area, but this may have been because there were too few patients to notice a clear difference.
Prof Peter Weissberg, medical director of the British Heart Foundation, said the treatment could have a major impact on patients undergoing a host pf procedures, if its benefits are proven in further studies.
He said: "The important thing is that this is just one procedure in which we know some brain damage is caused, so it is a good one in which to test the drug.
"If it turns out that this protects the brain, we could use it on umpteen procedures on the brain, so it might have a much broader umpact than just these patients."
Prof Michael Hill of the University of Calgary, who led the study, said safe drugs to protect the brain during operations that restrict blood flow to the brain was a "major unmet need in stroke treatment".
"Our research, which builds on existing animal studies, suggests that intravenous infusion of NA-1 reduces tissue damage in patients who suffer a small stroke after an operation to repair a brain aneurysm, and further research is now needed to investigate the efficacy of neuroprotection in larger clinical trials."
In a comment article accompanying the study, Dr Markku Kaste of Helsinki University added: "Only after such trials will we know whether NA-1 or one of the other drugs which have shown comparable effects is the long-awaited holy grail for the treatment of patients with ischaemic stroke."
Continued here:
New drug lowers stroke risk after surgery