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Exhibit (a)(1)(C)

Notice of Guaranteed Delivery
for Tender of Shares of Common Stock

of

TRIUS THERAPEUTICS, INC.

at

$13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upon the achievement of certain sales milestones

Pursuant to the Offer to Purchase

Dated August 13, 2013

by

BRGO CORPORATION

a wholly-owned subsidiary of

CUBIST PHARMACEUTICALS, INC.

(Not to be used for Signature Guarantees)

        This Notice of Guaranteed Delivery, or a form substantially equivalent hereto, must be used to accept the Offer (as defined below) if certificates representing shares of common stock, par value $0.0001 per share (the "Shares") of Trius Therapeutics, Inc., a Delaware corporation (the "Company"), are not immediately available, if the procedure for book-entry transfer cannot be completed on a timely basis, or if time will not permit all required documents be delivered to Computershare Trust Company, N.A. (the "Depositary") before the expiration of the Offer. This Notice of Guaranteed Delivery may be delivered by hand or transmitted by telegram, facsimile transmission or mail to the Depositary and must include a guarantee by an Eligible Institution (as defined in the Offer to Purchase). See "The Tender Offer—Section 2—Procedures for Tendering Shares" of the Offer to Purchase.

The Depositary for the Offer is:

By Mail:	By Overnight Courier:
Computershare Trust Company, N.A.	Computershare Trust Company, N.A.
c/o Voluntary Corporate Actions	c/o Voluntary Corporate Actions
P.O. Box 43011	Suite V
Providence, RI 02940-3011	250 Royall Street
	Canton, MA 02021

DELIVERY OF THIS NOTICE OF GUARANTEED DELIVERY TO AN ADDRESS OTHER THAN ONE SET FORTH ABOVE OR TRANSMISSION OF INSTRUCTIONS VIA FACSIMILE TO A NUMBER OTHER THAN THE FACSIMILE NUMBER SET FORTH ABOVE DOES NOT CONSTITUTE A VALID DELIVERY.

THIS NOTICE OF GUARANTEED DELIVERY TO THE DEPOSITARY IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.

THE GUARANTEE INCLUDED HEREIN MUST BE COMPLETED.

Ladies and Gentlemen:

The undersigned hereby tenders to BRGO Corporation, a Delaware corporation (the "Purchaser") and a wholly-owned subsidiary of Cubist Pharmaceuticals, Inc., a Delaware corporation ("Cubist"), upon the terms and subject to the conditions set forth in the Offer to Purchase, dated August 13, 2013 (the "Offer to Purchase"), and in the related Letter of Transmittal (which, together with any amendments or supplements thereto, collectively constitute the "Offer"), receipt of which is hereby acknowledged, the number of Shares set forth below, all pursuant to the guaranteed delivery procedures set forth in the Offer to Purchase.

Name(s) of Record Holder(s):

Number of Shares Tendered:

Certificate Number(s) (if available): (please print)

Address(es):
	(Zip Code)

o        Check if securities will be tendered by book-entry transfer

Name of Tendering Institution:

Area Code and Telephone No.(s):

Signature(s):

Account No.:

Transaction Code No.:

Dated:

GUARANTEE
(Not to be used for signature guarantee)

        The undersigned, a financial institution that is a member in good standing of the Security Transfer Agents Medallion Program, the New York Stock Exchange Medallion Signature Guarantee Program, the Stock Exchange Medallion Program or any other "eligible guarantor institution" (as defined in Rule 17Ad-15 under the Securities Exchange Act of 1934, as amended) (each of the foregoing, an "Eligible Institution"), hereby guarantees to deliver to Computershare Trust Company, N.A. (the "Depositary") either the certificates representing the Shares tendered hereby, in proper form for transfer, or to deliver Shares pursuant to the procedure for book-entry transfer into the Depositary's account at The Depository Trust Company (the "Book-Entry Transfer Facility"), in any such case together with a properly completed and duly executed Letter of Transmittal, with any required signature guarantees or an Agent's Message (as defined in the Offer to Purchase), and any other documents required by the Letter of Transmittal, all within three NASDAQ Global Market trading days after the date hereof.

        The Eligible Institution that completes this form must communicate the guarantee to the Depositary and must deliver the properly completed and duly executed Letter of Transmittal or an Agent's Message, certificates for Shares and/or any other required documents to the Depositary within the time period shown herein. Failure to do so could result in a financial loss to such Eligible Institution.

Name of Firm:

Address: (Zip Code)

Area Code and Tel. No.

(Authorized Signature)

Name:

(Please type or print)

Title:

Dated:

NOTE: DO NOT SEND CERTIFICATES FOR SHARES WITH THIS NOTICE. CERTIFICATES FOR SHARES SHOULD BE SENT WITH YOUR PROPERLY COMPLETED AND DULY EXECUTED LETTER OF TRANSMITTAL.

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Exhibit (a)(1)(C)