The outcome of Photothera’s clinical trial on 660 patients with acute ischemic stroke was presented at the American Heart Association’s International Stroke Conference in San Diego yesterday. Though results were not as good as hoped for there were some encouraging trends.
The LLLT group achieved a favourable outcome in 36.3% of patients compared to only 30.9% of patients in the placebo group at 90 days. However a post-hoc analysis of 434 patients who suffered moderate to moderately severe strokes showed a favorable outcome in 51.6% of patients in the TLT group compared to 41.9% of patients in the sham group. This 9.7% treatment effect was statistically significant (p-value 0.044). Adverse events did not differ between groups, providing evidence of the safety of LLLT.
It will be interesting to see the treatment parameters when the paper is published.
The results of NeuroThera Effectiveness and Safety Trial – 2 (NEST-2) Presented at International Stroke Conference 2009
Encouraging Safety and Efficacy Results Support Follow-on NEST-3 Trial
CARLSBAD, Calif., Feb. 20 — In a clinical trial sponsored by PhotoThera, Inc., transcranial laser therapy (TLT) for acute ischemic stroke within 24 hours of stroke onset demonstrated improved outcomes for patients, but did not meet statistical significance for efficacy. A post-hoc analysis in patients who had moderate to moderately severe strokes revealed a statistically significant treatment effect. These encouraging results support a follow-on phase III trial, NEST-3.
The results of the NEST-2 study (NeuroThera(R) Effectiveness and Safety Trial – 2) were presented at the American Heart Association’s International Stroke Conference in San Diego, CA by Justin Zivin, M.D., Ph.D., Professor of Neurosciences at the University of California San Diego and Principal Investigator for the NEST-2 study. The results were also published online today in Stroke: Journal of the American Heart Association.
NEST-2 was a double-blind, sham-controlled (placebo) trial which enrolled 660 patients. Patients were eligible for inclusion in the study if they were 40-90 years of age, had moderate to severe strokes, and had not received tissue plasminogen activator (tPA). Initiation of treatment had to occur within 24 hours after stroke onset.
In NEST-2, TLT achieved a favorable outcome in 36.3% of patients compared to only 30.9% of patients in the sham group (p-value 0.094). The primary efficacy endpoint was a favorable 90-day score of 0-2 using the modified Rankin Scale (mRS). Mortality rates and serious adverse events (SAEs) did not differ between groups, providing further evidence of the safety of TLT.
A post-hoc analysis of 434 patients who suffered moderate to moderately severe strokes showed a favorable outcome in 51.6% of patients in the TLT group compared to 41.9% of patients in the sham group. This 9.7% treatment effect was statistically significant (p-value 0.044).
“TLT is one of the most promising new therapies that we’ve seen in a long time, especially as it may expand the treatment window for ischemic stroke to 24 hours. We look forward to commencing NEST-3 to further investigate TLT,” stated Professor Werner Hacke, M.D., Ph.D., Chairman of Neurology at the University of Heidelberg, who will join Professor Zivin as Co-Chairman of the NEST-3 Steering Committee.
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“Although our primary endpoint of improvement for overall stroke disability missed reaching statistical significance, we saw no ill effects from the laser treatment. And, in fact, there was a strong signal that this treatment actually offered some improvement for patients with moderate to moderately severe strokes, even in the presence of prior risk factors such as previous stroke, heart disease and diabetes,” said Justin Zivin, M.D. Ph.D., principal investigator of the study and a professor of neurosciences at the University of California San Diego.
“For a trial that ‘failed,’ this one was reasonably encouraging,” Zivin said, a staff neurologist at the San Diego Veterans Administration (VA) Medical Center. “Laser therapy is unlike most treatments that have been tried for acute stroke.”
“We’re not mechanically injuring the brain at all,” Zivin said. “We shave off the patient’s hair and aim the laser at 20 points around the head so that the beam can cause a reaction in or around the damaged tissue.”
While the mechanisms of laser therapy are unknown, earlier animal studies indicated that spacing the laser therapy at 20 points around the skull was more effective that targeting one point. That may be because the 20-point approach allows infrared beams to cover the area of brain damage from many different angles, he said.
The only one approved by the Food and Drug Administration for the most common type of stroke, caused by a blood clot, is a clot-busting drug known as tissue plasminogen activator, or tPA, that must be given intravenously within three hours.
“We need something for patients who come in later than that,” Dr. Justin Zivin of the University of California San Diego, who led the study funded by PhotoThera, said in a telephone interview.