Exhibit 10.51

SEVENTH AMENDMENT TO LOAN AND SECURITY AGREEMENT

This Seventh Amendment to Loan aud Security Agreement (this "Amendment') is entered into as of June 11, 2011, by and between COMER1CA BANK
("Bank") and ARRAY BIOPHARMA, INC. ("Borrower").

RECITALS

Borrower and Bank are parties to that certain Loan and Security Agreement dated as of June 28, 2005, as amended from time to time, including
by that certain First Amendment to Loan and Security Agreement dated as of December 19, 2005, that certain Second Amendment to Loan and Security Agreement, Consent and Waiver dated as of
July 7, 2006, that certain Third Amendment to Loan and Security Agreement dated as of June 12, 2008, that certain Fourth Amendment to Loan and Security Agreement dated as of
March 11, 2009, that certain Fifth Amendment to Loan and Security Agreement dated as of September 30, 2009, that certain Sixth Amendment to Loan and Security Agreement dated as of
March 31, 2010 and that certain bilateral
extension letter dated as of March 4, 2011 (collectively, the "Agreement"). The parties desire to amend the Agreement in accordance with the terms of this Amendment.

NOW,
THEREFORE, the parties agree as follows:

1.     The
following defined term in Section 1.1 of the Agreement hereby is amended and restated as follows:

"Revolving
Maturity Date" means June 9, 2012.

2.     Notwithstanding
any other provisions of the Agreement to the contrary, Bank hereby consents to Borrower pledging up to Three Hundred Thousand Dollars ($300,000) of cash to American
Express to secure corporate credit card services provided by American Express.

3.     No
course of dealing on the part of Bank or its officers, nor any failure or delay in the exercise of any right by Bank, shall operate as a waiver thereof, and any single or partial
exercise of any such right shall not preclude any later exercise of any such right. Bank's failure at any time to require strict performance by Borrower of any provision shall not affect any right of
Bank thereafter to demand strict compliance and performance. Any suspension or waiver of a right must be in writing signed by an officer of Bank.

4.     Unless
otherwise defined, all initially capitalized terms in this Amendment shall be as defined in the Agreement. The Agreement, as amended hereby, shall be and remain in full force
and effect in accordance with its respective terms and hereby is ratified and confirmed in all respects. Except as expressly set forth herein, the execution, delivery, and performance of this
Amendment shall not operate as a waiver of, or as an amendment of, any right, power, or remedy of Bank under the Agreement, as in effect prior to the date hereof.

5.     Borrower
represents and warrants that the Representations and Warranties contained in the Agreement are true and correct as of the date of this Amendment, and that no Event of Default
has occurred and is continuing.

6.     As
a condition to the effectiveness of this Amendment, Bank shall have received, in form and substance satisfactory to Bank, the following:



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7.     This
Amendment may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one instrument.

[Balance of Page Intentionally Left Blank]

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

ARRAY BIOPHARMA, INC.By:

/s/ MIKE CARRUTHERSTitle:

CFOCOMERICA BANKBy:

/s/ MIKE FISHBACKTitle:

AVP


[Signature Page to Seventh Amendment to Loan and Security Agreement]

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