MMP9 and Stroke: Compared with historical controls, RP-1127 also reduced MMP-9 levels at 48 h post-stroke onset as measured by quantitative sandwich ELISA (54 ± 17 ng/mL vs. 212 ± 151 ng/mL, p < 0.01) and pro-MMP-9 enzyme levels (as measured by zymography; p < 0.01) [25].