15. SUBSEQUENT EVENT	9 Months Ended
Feb. 28, 2019
Subsequent Events [Abstract]
15. SUBSEQUENT EVENT	15. SUBSEQUENT EVENT At the maturity date of April 10, 2019, the Company repaid the debt in an aggregate principal amount of $6.1 million under the Purchase Agreement with QVT Fund LP and Quintessence Fund L.P.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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