Abstract
Granulocyte-colony stimulating factor (G-CSF: Filgrastim) may be useful for treatment of acute ischemic stroke owing to its neuroprotective and neurogenesis-promoting properties, but excessive increase of neutrophils may lead to brain injury. Here, we examined the safety and tolerability of low-dose G-CSF, and investigated the effectiveness of G-CSF given intravenously in the acute phase (at 24-hour) or sub-acute phase (at 7-day) of ischemic stroke. Leukocyte levels remained below 40,000/μl at 150 and 300 μg G-CSF/body/day, but rose above 40,000/μl at 450 μg G-CSF/body/day. Neurological function improvement between baseline and day 90 was more marked after treatment in the acute phase versus the sub-acute phase (Barthel Index 49.4±28.1 vs 15.0±22.0; p<0.01). Now we have started a phase II study of testing G-CSF, at those two doses and placebo that starts at 24 hours after ischemic stroke onset and continues for five days.
