Transcranial laser therapy for acute ischemic stroke: a pooled analysis of NEST-1 and NEST-2

Background NeuroThera Effectiveness and Safety Trials (NEST) 1 and 2 have demonstrated safety of transcranial laser therapy (TLT) for human treatment in acute ischemic stroke. NEST 1 study suggested efficacy of TLT but the following NEST 2, despite strong signals, missed reaching significance on its primary efficacy endpoint. In order to assess efficacy in a larger cohort, a pooled analysis was therefore performed. Methods The two studies were first compared for heterogeneity, and then a pooled analysis was performed to assess overall safety and efficacy, and examined particular subgroups. The primary endpoint for the pooled analysis was dichotomized modified Rankin scale (mRS) 0-2 at 90 days. Results Efficacy analysis for the intention-to-treat population was based on a total of 778 patients. Baseline characteristics and prognostic factors were balanced between the two groups. The TLT group (n=410) success rate measured by the dichotomized 90-day mRS was significantly higher compared with the sham group (n=368) (P=0 center dot 003, OR: 1 center dot 67, 95% CI: 1 center dot 19-2 center dot 35). The distribution of scores on the 90-day mRS was significantly different in TLT compared with sham (P=0 center dot 0005 Cochran-Mantel-Haenszel). Subgroup analysis identified moderate strokes as a predictor of better treatment response. Conclusions This pooled analysis support the likelihood that transcranial laser therapy is effective for the treatment of acute ischemic stroke when initiated within 24h of stroke onset. If ultimately confirmed, transcranial laser therapy will change management and improve outcomes of far more patients with acute ischemic stroke.