Single Ascending Oral Doses of SY-009 in Healthy Subjects

The study will be initiated in healthy subjects at a 0.5mg dose that is the maximum recommended starting dose(MRSD) . Doses will be escalated in subsequent dosing process, after appropriate review of safety data. The subsequent planned doses are 2,5, 10, 20, 40mg successively. The increment of the dose escalation may be reduced, a lower dose may be administered following data review.