Today in after-hours trade, shares of Athersys (ATHX) were up 21% after the company announced positive phase 2 results for its Stroke trial. The phase 2 trial had two different parts. One part had a small dose selection phase of 16 patients in two cohorts, and the other part had 118 patients in the efficacy phase. 

Patients were either given Athersys' Multi-stem cell therapy intravenously or received a placebo compound instead. The trial recruited patients with a type of stroke known as Ischemic stroke -- obstruction of blood going to the brain causing damage. This data presented today was a one-year followup of these patients who had improved in outcome. 

The Multistem therapy performed better than the placebo compound. For the 65 patients that took Multistem Cell therapy about 23% of them achieved an excellent outcome score at the one year mark, on the other hand about 8% of the placebo patients achieved an excellent outcome score. This difference means that the Multistem cell therapy was statistically significant compared to the placebo group.