Exhibit 10.1

EXECUTION VERSION

AMENDMENT NO. 1 TO LOAN AGREEMENT

THIS AMENDMENT NO. 1 TO LOAN AGREEMENT, dated as of October 11, 2017 (this “ Amendment ”), is made among Omeros Corporation, a Washington corporation (“ Borrower ”), CRG Servicing LLC, as administrative agent and collateral agent (in such capacities, “ Administrative Agent ”), and the lenders listed on the signature pages hereof (each, a “ Lender ” and, collectively, the “ Lenders ”), with respect to the Loan Agreement referred to below.

RECITALS

WHEREAS, Borrower, Administrative Agent and the Lenders are parties to the Term Loan Agreement, dated as of October 26, 2016, as partially waived pursuant to the Waiver to Loan Agreement, dated as of May 9, 2017 (the “ Waiver ”), with the Subsidiary Guarantors from time to time party thereto (the “ Loan Agreement ”).

WHEREAS, Borrower has requested that Administrative Agent and the Lenders (which Lenders constitute all of the Lenders party to the Loan Agreement), and Administrative Agent and the Lenders have agreed to, amend the conditions in Sections 6.03(b) and 6.04(d) , (e)  and (f)  of the Loan Agreement.

NOW, THEREFORE, in consideration of the mutual agreements, provisions and covenants contained herein, the parties agree as follows:

SECTION 1. Definitions; Interpretation .

(a) Terms Defined in Loan Agreement . All capitalized terms used in this Amendment (including in the recitals hereof) and not otherwise defined herein shall have the meanings assigned to them in the Loan Agreement.

(b) Interpretation . The rules of interpretation set forth in Section 1.03 of the Loan Agreement shall be applicable to this Amendment and are incorporated herein by this reference.

SECTION 2. Amendments . Subject to Section 3 of this Amendment:

SECTION 3. Conditions of Effectiveness . The effectiveness of Section 2 of this Amendment shall be subject to the following conditions precedent:

(a) Borrower, Administrative Agent and all of the Lenders shall have duly executed and delivered this Amendment pursuant to Section 13.04 of the Loan Agreement; provided , however , that this Amendment shall have no binding force or effect unless all conditions set forth in this Section 3 have been satisfied;

(b) No Default or Event of Default under the Loan Agreement shall have occurred and be continuing; and

(c) Borrower shall have paid or reimbursed Administrative Agent and the Lenders for their reasonable and documented out of pocket costs and expenses (including the reasonable and documented fees and expenses of Administrative Agent’s and the Lenders’ legal counsel) incurred in connection with this Amendment pursuant to Section 13.03(a)(i)(z) of the Loan Agreement.

SECTION 4. Reaffirmation . Borrower hereby ratifies, confirms, reaffirms, and acknowledges its obligations under the Loan Documents to which it is a party and agrees that the Loan Documents remain in full force and effect, undiminished by this Amendment, except as expressly provided herein, including, for the avoidance of doubt, Administrative Agent’s rights pursuant to Sections 8.01 , 8.02 and 8.06 of the Loan Agreement. By executing this Amendment, Borrower acknowledges that it has read, consulted with its attorneys regarding, and understands, this Amendment. For the avoidance of doubt, the parties confirm that the waiver of Sections 6.03(d) , (e)  and (f)  in the Waiver continue to apply.

SECTION 5. Governing Law; Submission to Jurisdiction; W AIVER OF J URY T RIAL .

(a) Governing Law . This Amendment and the rights and obligations of the parties hereunder shall be governed by, and construed in accordance with, the law of the State of New York, without regard to principles of conflicts of laws that would result in the application of the laws of any other jurisdiction; provided that Section 5-1401 of the New York General Obligations Law shall apply.

(b) Submission to Jurisdiction . Borrower agrees that any suit, action or proceeding with respect to this Amendment or any other Loan Document to which it is a party or any judgment entered by any court in respect thereof may be brought initially in the federal or state courts in Houston, Texas or in the courts of its own corporate domicile and irrevocably submits to the non-exclusive jurisdiction of each such court for the purpose of any such suit, action, proceeding or judgment. This Section 5 is for the benefit of Administrative Agent and the Lenders only and, as a result, none of Administrative Agent or any Lender shall be prevented from taking proceedings in any other courts with jurisdiction. To the extent allowed by applicable Laws, Administrative Agent and the Lenders may take concurrent proceedings in any number of jurisdictions.

(c) Waiver of Jury Trial . B ORROWER , A DMINISTRATIVE A GENT AND EACH L ENDER HEREBY IRREVOCABLY WAIVES , TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW , ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY SUIT , ACTION OR PROCEEDING ARISING OUT OF OR RELATING TO THIS A MENDMENT , THE OTHER L OAN D OCUMENTS OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY .

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SECTION 6. Miscellaneous .

(a) No Waiver . Except as expressly stated herein, nothing contained herein shall be deemed to constitute a waiver of compliance with any term or condition contained in the Loan Agreement or any of the other Loan Documents or constitute a course of conduct or dealing among the parties. Except as expressly stated herein, Administrative Agent and the Lenders reserve all rights, privileges and remedies under the Loan Documents. Except as amended hereby, the Loan Agreement and other Loan Documents remain unmodified and in full force and effect. All references in the Loan Documents to the Loan Agreement shall be deemed to be references to the Loan Agreement as amended hereby.

(b) Severability . In case any provision of or obligation under this Amendment shall be invalid, illegal or unenforceable in any jurisdiction, the validity, legality and enforceability of the remaining provisions or obligations, or of such provision or obligation in any other jurisdiction, shall not in any way be affected or impaired thereby.

(c) Headings . Headings and captions used in this Amendment (including the Exhibits, Schedules and Annexes hereto, if any) are included for convenience of reference only and shall not be given any substantive effect.

(d) Integration . This Amendment constitutes a Loan Document and, together with the other Loan Documents, incorporates all negotiations of the parties hereto with respect to the subject matter hereof and is the final expression and agreement of the parties hereto with respect to the subject matter hereof.

(e) Counterparts . This Amendment may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument and any of the parties hereto may execute this Amendment by signing any such counterpart. Executed counterparts delivered by facsimile or other electronic transmission (e.g., “PDF” or “TIF”) shall be effective as delivery of a manually executed counterpart.

(f) Controlling Provisions . In the event of any inconsistencies between the provisions of this Amendment and the provisions of any other Loan Document, the provisions of this Amendment shall govern and prevail. Except as expressly modified by this Amendment, the Loan Documents shall not be modified and shall remain in full force and effect.

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

[Signature Page – Amendment No. 1]

[Signature Page – Amendment No. 1]