HAND DELIVERED March 12, 2012 Mr. Perry Van Crocker, Jr. AuraSense Therapeutics, LLC Vice President Commercial Development

EXHIBIT 10.13

HAND DELIVERED

March 12, 2012

Xx. Xxxxx Xxx Xxxxxxx, Xx.

AuraSense Therapeutics, LLC

Vice President Commercial Development

0000 Xxxxx Xxxxxx, Xxxxx 0000

Evanston, IL 60201

RE: Lease Agreement between FC SKOKIE SPE, LLC (“Landlord”) and AURASENSE THERAPEUTICS, LLC (“Tenant”) dated February 13, 2012

Dear Xx. Xxxxxxx,

Pursuant to Section 2.5 of the above referenced lease this is to confirm that the Initial Rent Commencement Date shall be March 12, 2012 and that the Delayed Rent Commencement Date shall be August 12, 2012.

Please indicate your concurrence with the above by countersigning a copy of the letter and returning a copy to me.

If you have any questions please don’t hesitate to contact me.

Sincerely,

Xxxxxxx Xxxxxx Asset Management		AURASENSE THERAPEUTICS, LLC
		/s/Xxxxx Xxx Xxxxxxx, Xx.
/s/Xxxxxxx Xxxxxx		By:
		Date: 3/12/2012

cc:		Xxxxx Xxxxxxxxx, AuraSense
		Xxxx Xxxx, Forest City
		Xxxxxxx Xxxxx, Esquire
		Xxxxx Xxxxxxxxx, CBRE

MF/mmm