Exhibit 10.1

FOURTH AMENDMENT

TO

OFFICE LEASE AGREEMENT

THIS FOURTH AMENDMENT TO OFFICE LEASE AGREEMENT (“Amendment”) is dated for
reference purposes the 27th day of September, 2012, by and between CITY CENTRE
ASSOCIATES, a Delaware general partnership (“Landlord”), and OMEROS CORPORATION,
a Washington corporation (“Tenant”).

RECITALS

A. Landlord’s predecessor in interest, Bentall City Centre L.L.C., and Tenant’s
predecessor in interest, Scope International, Inc., entered into that certain
U.S. Bank Centre Office Lease Agreement dated as of September 28, 1998, as
amended by an Assignment and Amendment of Lease dated August 1, 2002, the Second
Amendment to Office Lease Agreement dated January 4, 2006, and the Third
Amendment to Office Lease Agreement dated October 4, 2010 (as amended, “Lease”),
for the lease of certain premises located in the U.S. Bank Centre, 1420 Fifth
Avenue, Seattle, Washington, and commonly known as Suites 2628 and 2675 and
consisting of a total of 13,156 rentable square feet (“Premises”).

B. Landlord and Tenant desire to confirm Tenant’s election to terminate the
Lease early.

NOW, THEREFORE, for valuable consideration, the receipt and sufficiency of which
is hereby acknowledged, the parties agree as follows:

1. Defined Terms; Conflict. Capitalized terms used herein and not otherwise
defined shall have the meanings given in the Lease. If there is any conflict
between the terms, conditions and provisions of this Amendment and the terms and
conditions of the Lease, the terms, conditions and provisions of this Amendment
shall prevail.

2. Lease Termination. Pursuant to Tenant’s right to early Lease termination
pursuant to Section 6 of the Third Amendment of Office Lease Agreement dated
October 4, 2010, Tenant has elected to terminate the Lease by delivering written
Termination Notice dated January 30, 2012. Landlord and Tenant hereby agree to
terminate the Lease effective November 30, 2012, notwithstanding the Lease
requirement for 12 months advance notice of the termination date.

3. Surrender of Premises. On or before November 30, 2012, Tenant shall surrender
the premises in a condition required under Section 13.2 of the Lease, provided,
however, that Tenant shall not be required to remove telecommunication and
computer network cabling.

4. Commission Reimbursement. Landlord acknowledges receipt from Tenant of the
Commission Reimbursement in the amount of $33,829.71, as required by the Third
Amendment, and that no further Commission Reimbursement is owed by Tenant under
Section 6 of the Third Amendment by virtue of this Amendment.

 

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5. No Further Amendment; Ratification. Except as expressly modified by this
Amendment, all terms, covenants and provisions of the Lease shall remain
unmodified and in full force and effect and are hereby expressly ratified and
confirmed.

6. Confirmation. Tenant represents and warrants to the best of its knowledge to
Landlord that: (a) no defenses or offsets exist to the enforcement of the Lease
by Landlord; (b) Landlord is not in default in the performance of the Lease and
Tenant has no unresolved or pending claims against Landlord with respect to the
Lease or the Premises; and (c) Landlord has not committed any breach of the
Lease, nor has any event occurred which, with the passage of time or the giving
of notice or both, would constitute a default or a breach by Landlord under the
Lease. Landlord represents and warrants to the best of its knowledge to Tenant
that: (a) no defenses or offsets exist to the enforcement of the Lease by
Tenant; (b) Tenant is not in default in the performance of the Lease and
Landlord has no unresolved or pending claims against Tenant with respect to the
Lease or the Premises; and (c) Tenant has not committed any breach of the Lease,
nor has any event occurred which, with the passage of time or the giving of
notice or both, would constitute a default or a breach by Tenant under the
Lease.

7. Entire Agreement. This Amendment sets forth the entire agreement of the
parties as to the subject matter hereof and supersedes all prior discussions and
understandings between them. The parties confirm and acknowledge that there are
no other promises, covenants, understandings, agreements, representations or
warranties with respect to the subject matter of this Amendment except as
expressly set forth herein. This Amendment may not be amended or rescinded in
any manner except by an instrument in writing signed by a duly authorized
officer or representative of each party hereto. No waiver of any right under
this Amendment shall be effective unless contained in a writing signed by a duly
authorized officer or representative of the party sought to be charged with the
waiver and no waiver of any right arising from any breach or failure to perform
shall be deemed to be a waiver of any future right or of any other right arising
under this Amendment.

8. Representation. Tenant acknowledges that it has been represented, or has had
sufficient opportunity to obtain representation of counsel with respect to this
Amendment. Tenant represents to Landlord that Tenant has read and understood the
terms hereof and the consequences of executing this Amendment and that, except
as expressly set forth herein, no representations have been made to Tenant to
induce the execution of this Amendment. Tenant waives any right it may have to
require the provisions of this Amendment to be construed against the party who
drafted it.

9. Authority. Each person signing this Amendment on behalf of the respective
parties represents and warrants that he or she is authorized to execute and
deliver this Amendment, and that this Amendment will thereby become binding upon
Landlord and Tenant, respectively.

 

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10. Counterparts. This Amendment may be executed in counterparts, each of which
will be deemed to be an original, but all of which together will constitute one
and the same document. To facilitate execution, this Amendment may be
transmitted electronically by facsimile or .pdf format to the other party and
that executed electronically transmitted counterpart shall be binding and
enforceable as an original.

IN WITNESS WHEREOF, the parties have executed this Amendment as of the date
first written above.

 

LANDLORD:       CITY CENTRE ASSOCIATES,       a Delaware general partnership   
   By:   

BCC EQUITY L.L.C.,

a Washington limited liability company,

Its Managing Joint Venturer

                 By:   

BENTALL KENNEDY REAL ESTATE

SERVICES (U.S.), INC., a California

corporation, Its Authorized Agent

                    By:   

    /s/ Gary J. Carpenter

               Gary J. Carpenter                Executive Vice President      
              By:   

    /s/ Betsy Sutherland

              

Betsy Sutherland

Vice President and

Regional Manager

TENANT:       OMEROS CORPORATION, a Washington corporation       By:   

    /s/ Gregory A. Demopulos, M.D.

      Its:        Chairman and CEO

 

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