To date, 29 patients have been enrolled. All patients had anterior circulation strokes (proximal MCA and terminal ICA). The baseline median National Institute of Health Stroke Scale score is 12.5 (range, 3-25). Symptomatic intracerebral hemorrhage has occurred in 2 patients, including 1 with parenchymal hemorrhage type 2 (7%). Asymptomatic bleeding occurred in 2 patients and there was 1 death. Compared to historical controls of IV-tPA alone, the 2-hour rate of complete recanalization is more than doubled in the argatroban-treated patients (38% vs 13%). Conclusion: The combination of low-dose argatroban and intravenous rtPA may be safe, and produce faster and more complete recanalization, but a larger cohort of patients is required to confirm this pilot study. Assuming safety is confirmed, the recanalization data will be used to design a larger Phase III trial.