Subsequent Event	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Event	(11) Subsequent Event In January 2019, the Company amended the Sales Agreement to increase the maximum aggregate value of shares which it may issue and sell from time to time under the Sales Agreement by approximately $2.5 million, from $10.2 million to $12.7 million. Subsequent to December 31, 2018, the Company sold an aggregate of 4,431,053 shares of its Common Stock pursuant to the terms of the Sales Agreement, as amended, for aggregate gross proceeds of approximately $2.5 million. Net proceeds received in the period were approximately $2.4 million, after deducting initial expenses for executing the “at the market offering” and commissions paid to the placement agent. As of February 22, 2019, the Company has sold all shares available under its current prospectus to the Company’s registration statement on Form S-3 (No. 333-217450).

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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