HEALIOS K.K. conducted the TREASURE study to investigate the safety and efficacy of HLCM051 (Multistem®) in patients with ischemic stroke. Healios is continuing discussions with the regulatory authority (PMDA) regarding future data acquisition and submission policies. Athersys Inc. ("Athersys") is conducting a clinical trial (trial name: MASTERS-2 study) in the U.S. and Europe using the same drug for ischemic stroke and completed the interim analysis of the clinical trial.

The interim analysis was conducted in the middle of the clinical trial to review the reestablishment of the required number of patients. As a result of the analysis based on the one-year follow-up of approximately half of the 300 patients in the trial, Athersys concluded that the current sample size of 300 patients is insufficiently powered to achieve the primary endpoint of mRS Shift analysis at Day 365. There were no safety issues identified.

Because the sample size required to achieve statistical significance is considerably larger, Athersys intends to conduct additional data analysis with independent statisticians. Athersys plans to pause enrollment of new patients while this analysis is being conducted. Healios will await the results of this analysis before taking any further action.