A phase IIa trial of JX10, a novel thrombolytic agent, showed promising safety and efficacy in extending the therapeutic window for acute ischemic stroke up to 12 hours after symptom onset.

In the multicenter, randomized trial, published in Stroke, researchers evaluated 90 Japanese patients who received JX10 or placebo, with a median treatment time of 9.5 hours after last known normal.

No symptomatic intracranial hemorrhage events occurred in JX10-treated patients within 24 hours compared with one event in the placebo group. Among patients with baseline vessel occlusion, recanalization at 24 hours occurred in 58.3% of the patients who received JX10 vs 26.7% of those who received placebo.

At 90 days, 40.4% of JX10-treated patients achieved functional independence (modified Rankin Scale 0 to 1) compared with 18.4% of those who received placebo (P = .03).

JX10 operates through dual mechanisms, promoting physiological fibrinolysis and inhibiting soluble epoxide hydrolase. Current approved thrombolytics like tissue plasminogen activator are limited to a 4.5-hour treatment window.

The study included patients ineligible for standard reperfusion therapies with National Institutes of Health Stroke Scale scores of 6 to 23. Three doses were evaluated: 1, 3, and 6 mg/kg.

Adverse events occurred similarly between groups, with constipation being most common. No major bleeding events occurred through day 7.

Study limitations included predominantly male enrollment, exclusion of patients over 88 years, and insufficient numbers of large vessel occlusion cases. The researchers noted larger studies are needed to confirm findings across broader populations.

The trial was funded by TMS Co, Ltd and Biogen Inc. Conflict of interests can be found in the study.