Laura S. Marshall, email@example.com
CARLSBAD, Calif. – You know the old adage “If at first you don’t succeed, try, try again.”
Well, that’s what PhotoThera Inc. is doing with its NeuroThera System, which is designed to treat stroke patients with transcranial laser therapy (TLT). The device recently was tested in a clinical trial, and the results were less than ideal.
Its impact on stroke disability did not achieve statistical significance for the overall group of stroke patients tested. Disability for 36.3 percent improved to mild or none within 90 days, compared with 30.9 percent of patients who received nonlaser therapy. Statistical significance would require a greater difference than 5.4 percent.
But the clinical trial results did offer one ray of hope: “We did notice that patients with moderate to moderately severe strokes showed benefit when treated with TLT,” said Luis De Taboada, vice president of research and development at PhotoThera. “This, in combination with the 24-hour treatment window, could significantly expand the treatment options for patients suffering from a stroke.”
For the group of patients considered to have moderate to moderately severe stroke impairment, 51.6 percent in the TLT group improved to the mild or no disability range in 90 days, compared with 41.9 percent of the control group. That 9.7 percent absolute improvement in treated patients turns out to be statistically significant.
Because the NeuroThera System is still in testing, the device is limited by federal law to investigational use. Images courtesy of PhotoThera Inc.
The NeuroThera System, De Taboada said, consists of a fiber optic cable, a handpiece, a cap that guides the laser energy to treatment locations on the scalp, accessories and a cart for portability.
When the system establishes contact with the patient’s completely shaved head, detectors in the handpiece trigger it to emit a specific wavelength of near-IR energy. “A total treatment regimen consists of treating 20 locations on the head for two minutes at each location for a total of 40 minutes of nominal treatment time,” De Taboada said.
The mitochondrial photoreceptor cytochrome C oxidase absorbs near-IR and drives adenosine triphosphate (ATP) formation by oxidative phosphorylation, he explained. The hypothesis goes that improved energy metabolism leads to mitigation of cell death in the stroke-affected tissue and to the enhancement of neuro-recovery mechanisms.
The improved neurometabolism could be beneficial not only in stroke treatment, but also in treating traumatic brain injury, and Parkinson’s and Alzheimer’s diseases, he said.
And although the NeuroThera Effectiveness and Safety Trial 2 (NEST-2) didn’t go entirely as planned, De Taboada and PhotoThera are encouraged by the results.
The NeuroThera System, designed to treat stroke patients, directs near-IR energy into brain tissue.
“Given the positive data we’ve seen in patients with moderate to moderately severe strokes in NEST-2,” he said, “we are currently planning a follow-on NEST-3 trial with refined patient criteria. We plan to have modified inclusion /exclusion criteria soon.”
He pointed out that stroke is the third leading cause of death in the US as well as the nation’s No. 1 cause of permanent disability. At present, the only FDA-approved treatment for an ischemic stroke – one related to lack of blood supply – is an intravenous thrombolytic drug called tissue plasminogen activator, or tPA, which must be administered within hours of symptom onset.
Despite evidence for a 4.5-h time window for thrombolytic, or clot-busting, therapy and despite the availability of thrombectomy devices, he added, less than 4 percent of patients receive any therapy beyond rehabilitation and prophylaxis. “Any improvement in expanding the time to treatment would be a significant breakthrough for the treatment of stroke,” De Taboada said.
He has some positive words for other biophotonics companies that might find themselves in a similar situation after a primary-end-point failure in clinical trials.
“This is an exciting time to be in biophotonics, given the merging of our discoveries in the biochemistry behind diseases and the impressive technological advances made in lasers, computer processing and imaging over the past ten years,” he said. “And working with the right people, understanding the disease states you are investigating at a very detailed level, and preparing for lengthy research efforts are crucial for success.”