SECOND AMENDMENT TO LEASE

Exhibit 10.28

SECOND AMENDMENT TO LEASE

THIS SECOND AMENDMENT (“Second Amendment”) is made by and between the Regents of the University of New Mexico, a body corporate of the State of New Mexico, as Landlord, and Exagen Diagnostics, Inc., as Tenant.

WHEREAS, in May 2013, Tenant entered into a Lease with Landlord for space at 000 Xxxxxxxx Xx.XX known as Suite 108 (the “Lease”);

WHEREAS, in April 2014, Tenant entered into a First Amendment to lease, exercising its First Option to extend the initial term of the Lease Agreement for six (6) additional months; and

WHEREAS, Tenant now desires, and Landlord agrees, to extend the Lease Term by an additional six (6) months.

NOW THEREFORE, Tenant and Landlord mutually agree and covenant as follows:

1. Landlord and Tenant agree to extend the Lease Term for six (6) months to commence December 1, 2014 and expire on May 31, 2015.

2. The monthly rent amount shall remain, Four Thousand Two Hundred and Five Dollars and Thirty-four cents ($4,205.34).

3. All capitalized terms used, but not defined, in this Second Amendment shall have the meaning ascribed to them in the Lease.

4. Except as amended herein, all other terms and conditions of the Lease shall remain unmodified and in full force and effect.

IN WITNESS WHEREOF, the parties have caused this Second Amendment to be executed by their duly authorized representatives.

LANDLORD: The Regents of the University of New Mexico
		/s/ Xxxxx X. Xxxxxx
By:		Xxxxx X. Xxxxxx
Its:		EVP for Administration, COO & CFO

		/s/ Xxxxx Xxxxxxx
By:		Xxxxx Xxxxxxx
Its:		Chief Procurement Officer

TENANT: Exagen Diagnostics, Inc.,
		/s/ Xxxxx Xxxxxxx
By:		Xxxxx Xxxxxxx
Its:		Chief Financial Officer and Chief Operations Officer

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