EXHIBIT 1

Joint Filing Agreement

The undersigned hereby agree that they are filing this statement jointly pursuant to Rule 13d-1(k)(1). Each of them is responsible for the timely filing of such Schedule 13G, and for the completeness and accuracy of the information concerning such person contained therein; but none of them is responsible for the completeness or accuracy of the information concerning the other persons making the filing, unless such person knows or has reason to believe that such information is inaccurate.

In accordance with Rule 13d-1(k)(1) promulgated under the Securities and Exchange Act of 1934, as amended, the undersigned hereby agree to the joint filing with each other on behalf of each of them of such Schedule 13G with respect to the Common Shares of the Issuer, beneficially owned by each of them. This Joint Filing Agreement shall be included as an exhibit to such Schedule 13G.

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IN WITNESS WHEREOF, the undersigned hereby execute this Agreement as of November 1, 2019.

LINCOLN PARK CAPITAL FUND, LLC        BY: LINCOLN PARK CAPITAL, LLC     BY: ROCKLEDGE CAPITAL CORPORATION		LINCOLN PARK CAPITAL, LLC  BY: ROCKLEDGE CAPITAL CORPORATION
By:	/s/ Joshua B. Scheinfeld	By:	/s/ Joshua B. Scheinfeld
	Name: Joshua B. Scheinfeld Title:   President		Name: Joshua B. Scheinfeld Title:  President
LINCOLN PARK CAPITAL FUND, LLC BY: LINCOLN PARK CAPITAL, LLC BY: ALEX NOAH INVESTORS, INC.		LINCOLN PARK CAPITAL, LLC BY: ALEX NOAH INVESTORS, INC.
By:	/s/ Jonathan I. Cope	By:	/s/ Jonathan I. Cope
	Name: Jonathan I. Cope Title:   President		Name: Jonathan I. Cope Title:   President
ROCKLEDGE CAPITAL CORPORATION		ALEX NOAH INVESTORS, INC.
By:	/s/ Joshua B. Scheinfel	By:	/s/ Jonathan I. Cope
	Name: Joshua B. Scheinfeld Title:  President		Name: Jonathan I. Cope Title:   President
JOSHUA B. SCHEINFELD		JONATHAN I. COPE
By:	/s/ Joshua B. Scheinfeld	By:	/s/ Jonathan I. Cope
	Name: Joshua B. Scheinfeld Title:   President		Name: Jonathan I. Cope Title:   President