Introduction: In pre-clinical studies, extended-release niacin has been shown to increase neurogenesis, synaptogenesis, and angiogenesis in a rat model of experimental middle cerebral artery (MCA) occlusion. Using this animal model, extended-release niacin has been shown to improve functional outcomes in rats when compared to placebo, beginning 24 hours after experimental stroke.
Methods: This was a phase IIa double-blind, randomized, placebo controlled study (Henry Ford Health System funded; clinicaltrials.gov NCT00796887). At a single site (Henry Ford Hospital, Detroit, MI), patients with ischemic stroke 3 to 7 days prior and NIHSS 4-20 were randomized to two doses of oral extended-release niacin (500 mg or 1000 mg daily) or placebo. Primary outcome measures were change in mRS or NIHSS from baseline to Week 24.
Results: There were 27 patients enrolled in this study. Ten patients were randomized to extended-release niacin 500 mg, 7 to 1000mg, and 10 to placebo. No significant differences were seen in baseline characteristics of enrolled patients. Significant increases in HDL-C were seen from baseline to 24 weeks among extended-release niacin treated patients (12.5 mg/dL, p=0.035), but not in placebo-treated patients (6.2 mg/dL, p=0.157). Mean improvement in NIHSS from baseline to 24 weeks of treatment was similar for both extended-release niacin and placebo treated patients (6.5 vs. 6.1, p=0.845). No differences were seen in functional outcome (mRS) at 24 weeks between extended-release niacin and placebo treated patients (2.1 vs. 2.0, p=0.860). There were a total of 40 AEs, with 27 in the extended-release niacin group and 10 in the placebo group. For these AEs, no clear interaction with treatment group could be confirmed.
Conclusions: Extended-release niacin administered for 24 weeks starting between 3 and 7 days after ischemic stroke demonstrated no improvement in functional outcome as compared to placebo. Extended-release niacin was overall well tolerated. Although this small exploratory study did not identify a signal for potential efficacy, useful sample size estimates were gleaned. Any future clinical investigations may benefit from the collection of additional clinical measures of motor or gait function to differentiate treatment effects.