Exhibit 1

Agreement of Joint Filing

Pursuant to 13d-1(k)(1) promulgated under the Securities Exchange Act of 1934, the undersigned persons hereby agree to file with the Securities and Exchange Commission the Statement on Schedule 13D (the “Statement”) to which this Agreement is attached as an exhibit, and agree that such Statement, as so filed, is filed on behalf of each of them.

IN WITNESS WHEREOF, the undersigned have executed this Agreement.

Dated: May 20, 2013

QVT FINANCIAL LP By: QVT Financial GP LLC, its General Partner		QVT FUND V LP By: QVT Associates GP LLC, its General Partner
By:	/s/ Tracy Fu	By:	/s/ Tracy Fu
Name:	Tracy Fu	Name:	Tracy Fu
Title:	Managing Member	Title:	Managing Member
By:	/s/ Nicholas Brumm	By:	/s/ Nicholas Brumm
Name:	Nicholas Brumm	Name:	Nicholas Brumm
Title:	Managing Member	Title:	Managing Member
QVT FINANCIAL GP LLC		QVT ASSOCIATES GP LLC
By:	/s/ Tracy Fu	By:	/s/ Tracy Fu
Name:	Tracy Fu	Name:	Tracy Fu
Title:	Managing Member	Title:	Managing Member
By:	/s/ Nicholas Brumm	By:	/s/ Nicholas Brumm
Name:	Nicholas Brumm	Name:	Nicholas Brumm
Title:	Managing Member	Title:	Managing Member

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