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                                                                Exhibit 10.45



                            INDEMNIFICATION AGREEMENT

     THIS AGREEMENT is made and entered into this 27th day of July 2001 by and
between MICROCIDE PHARMACEUTICALS, INC., a Delaware corporation (the
"Corporation"), and DAVID SCHNELL ("Schnell").


                                    RECITALS

     WHEREAS, Schnell was formerly a director of the Corporation;

     WHEREAS, after resigning as a director of the Corporation, Schnell, in his
capacity as Member of Prospect Management Co., LLC, the General Partner of
Prospect Venture Partners L.P., and Member of Prospect Management Co. II, LLC,
the General Partner of Prospect Venture Partners II (collectively, "Prospect"),
has, on behalf of Prospect and other potential investors, proposed, arranged and
participated in negotiations for a $60,000,000 preferred stock financing and the
transactions contemplated thereby (the "Financing") for the Corporation; and

     WHEREAS, in order to induce Schnell, in his various capacities with
Prospect, and Prospect to participate in the Financing, the Corporation has
determined and agreed to enter into this Agreement with Schnell;

     NOW, THEREFORE, in consideration of the premises and the mutual covenants
contained herein and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto agree as
follows:

                                    AGREEMENT

     1. Indemnity of Schnell. Subject only to the exclusions set forth in
Section 2 hereof, the Corporation hereby agrees to hold harmless and indemnify
Schnell against any and all expenses (including attorneys' fees), witness fees,
damages, judgments, fines and amounts paid in settlement and any other amounts
that Schnell directly or indirectly suffers or incurs or may otherwise become
subject at any time and which arise directly or indirectly from or as a direct
or indirect result of, or are directly or indirectly connected with any claim or
claims made against or by him in connection with any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, arbitrational,
administrative or investigative (including an action by or in the right of the
Corporation) to which Schnell is, was or at any time becomes a party, or is
threatened to be made a party, by reason of the fact that Schnell was a director
of the Corporation and/or, either in his various capacities with Prospect or
otherwise, proposed, arranged, negotiated and/or participated in the Financing.

     2. Limitations on Additional Indemnity. No indemnity pursuant to Section 1
hereof shall be paid by the Corporation:

          (a) on account of Schnell's conduct that is established by a final
     judgment as knowingly fraudulent or deliberately dishonest or that
     constituted willful misconduct;

          (b) for which payment is actually made to Schnell under a valid and
     collectible insurance policy or under a valid and enforceable indemnity
     clause, bylaw or agreement, except in respect of any excess beyond payment
     under such insurance, clause, bylaw or agreement;

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          (c) if indemnification is not lawful; or

          (d) in connection with any proceeding (or part thereof) initiated by
     Schnell, or any proceeding by Schnell against the Corporation or its
     directors, officers, employees or other agents, unless (i) such
     indemnification is expressly required to be made by law, (ii) the
     proceeding was authorized by the Board of Directors of the Corporation, or
     (iii) the proceeding is initiated pursuant to Section 7 hereof.

     3. Continuation of Indemnity. All agreements and obligations of the
Corporation contained herein shall continue so long as Schnell shall be subject
to any possible claim or threatened, pending or completed action, suit or
proceeding, whether civil, criminal, arbitrational, administrative or
investigative, by reason of the fact that Schnell was serving in the capacity
referred to in the recitals section of this Agreement.

     4. Partial Indemnification. Schnell shall be entitled under this Agreement
to indemnification by the Corporation for a portion of the expenses (including
attorneys' fees), witness fees, damages, judgments, fines and amounts paid in
settlement and any other amounts that Schnell directly or indirectly suffers or
incurs or may otherwise become subject at any time and which arise directly or
indirectly from or as a direct or indirect result of, or are directly or
indirectly connected with any action, suit or proceeding referred to in Section
1 hereof even if not entitled hereunder to indemnification for the total amount
thereof, and the Corporation shall indemnify Schnell for the portion thereof to
which Schnell is entitled.

     5. Notification and Defense of Claim. Not later than seven (7) business
days after receipt by Schnell of notice of the commencement of any action, suit
or proceeding, Schnell will, if a claim in respect thereof is to be made against
the Corporation under this Agreement, notify the Corporation of the commencement
thereof; but the omission so to notify the Corporation will not relieve it from
any liability which it may have to Schnell otherwise than under this Agreement.
With respect to any such action, suit or proceeding as to which Schnell notifies
the Corporation of the commencement thereof:

          (a) the Corporation will be entitled to participate therein at its own
     expense;

          (b) except as otherwise provided below, the Corporation may, at its
     option and jointly with any other indemnifying party similarly notified and
     electing to assume such defense, assume the defense thereof, with counsel
     reasonably satisfactory to Schnell. After notice from the Corporation to
     Schnell of its election to assume the defense thereof, the Corporation will
     not be liable to Schnell under this Agreement for any legal or other
     expenses subsequently incurred by Schnell in connection with the defense
     thereof except for reasonable costs of investigation or otherwise as
     provided below. Schnell shall have the right to employ separate counsel in
     such action, suit or proceeding but the fees and expenses of such counsel
     incurred after notice from the Corporation of its assumption of the defense
     thereof shall be at the expense of Schnell unless (i) the employment of
     counsel by Schnell has been authorized by the Corporation, (ii) Schnell
     shall have reasonably concluded, and so notified the Corporation, that
     there is an actual conflict of interest between the Corporation and Schnell
     in the conduct of the defense of such action or (iii) the Corporation shall
     not in fact have employed counsel to assume the defense of such action, in
     each of which cases the fees and expenses of Schnell's separate counsel
     shall be at the expense of the Corporation. The Corporation shall not be
     entitled to assume the defense of any action, suit or proceeding brought by
     or on behalf of the Corporation or as to which Schnell shall have made the
     conclusion provided for in clause (ii) above; and


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          (c) the Corporation shall not be liable to indemnify Schnell under
     this Agreement for any amounts paid in settlement of any action or claim
     effected without its written consent, which shall not be unreasonably
     withheld. The Corporation shall be permitted to settle any action except
     that it shall not settle any action or claim in any manner which would
     impose any penalty or limitation on Schnell without Schnell's written
     consent, which may be given or withheld in Schnell's sole discretion.

     6. Expenses. The Corporation shall advance, prior to the final disposition
of any proceeding, promptly following request therefor, all expenses incurred by
Schnell in connection with such proceeding upon receipt of an undertaking by or
on behalf of Schnell to repay said amounts if it shall be determined ultimately
that Schnell is not entitled to be indemnified under the provisions of this
Agreement or otherwise.

     7. Enforcement. Any right to indemnification or advances granted by this
Agreement to Schnell shall be enforceable by or on behalf of Schnell in any
court of competent jurisdiction if (a) the claim for indemnification or advances
is denied, in whole or in part, or (b) no disposition of such claim is made
within ninety (90) days of request therefor. Schnell, in such enforcement
action, if successful in whole or in part, shall be entitled to be paid also the
expense of prosecuting his claim. It shall be a defense to any action for which
a claim for indemnification is made under Section 1 hereof (other than an action
brought to enforce a claim for expenses pursuant to Section 6 hereof, provided
that the required undertaking has been tendered to the Corporation) that Schnell
is not entitled to indemnification because of the limitations set forth in
Section 2 hereof. Neither the failure of the Corporation (including its Board of
Directors or its stockholders) to have made a determination prior to the
commencement of such enforcement action that indemnification of Schnell is
proper in the circumstances, nor an actual determination by the Corporation
(including its Board of Directors or its stockholders) that such indemnification
is improper shall be a defense to the action or create a presumption that
Schnell is not entitled to indemnification under this Agreement or otherwise.

     8. Subrogation. In the event of payment under this Agreement, the
Corporation shall be subrogated to the extent of such payment to all of the
rights of recovery of Schnell, who shall execute all documents required and
shall do all acts that may be necessary to secure such rights and to enable the
Corporation effectively to bring suit to enforce such rights.

     9. Non-Exclusivity of Rights. The rights conferred on Schnell by this
Agreement shall not be exclusive of any other right which Schnell may have or
hereafter acquire under any statute, provision of the Corporation's charter
documents, agreement, vote of stockholders or directors, or otherwise.

     10. Survival of Rights.

          (a) The rights conferred on Schnell by this Agreement shall inure to
     the benefit of Schnell's heirs, executors and administrators.

          (b) The Corporation shall require any successor (whether direct or
     indirect, by purchase, merger, consolidation or otherwise) to all or
     substantially all of the business or assets of the Corporation, expressly
     to assume and agree to perform this Agreement in the same manner and to the
     same extent that the Corporation would be required to perform if no such
     succession had taken place.


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     11. Severability. Each of the provisions of this Agreement is a separate
and distinct agreement and independent of the others, so that if any provision
hereof shall be held to be invalid for any reason, such invalidity or
unenforceability shall not affect the validity or enforceability of the other
provisions hereof. Furthermore, if this Agreement shall be invalidated in its
entirety on any ground, then the Corporation shall nevertheless indemnify
Schnell to the fullest extent provided by any applicable law.

     12. Governing Law. This Agreement shall be interpreted and enforced in
accordance with the laws of the State of Delaware.

     13. Amendment and Termination. No amendment, modification, termination or
cancellation of this Agreement shall be effective unless in writing signed by
both parties hereto.

     14. Identical Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall for all purposes be deemed to be an original
but all of which together shall constitute but one and the same Agreement. Only
one such counterpart need be produced to evidence the existence of this
Agreement.

     15. Headings. The headings of the sections of this Agreement are inserted
for convenience only and shall not be deemed to constitute part of this
Agreement or to affect the construction hereof.

     16. Notices. All notices, requests, demands and other communications
hereunder shall be in writing and shall be deemed to have been duly given upon
delivery if delivered by hand to the party to whom such communication was
directed or upon the third business day after the date on which such
communication was mailed if mailed by certified or registered mail with postage
prepaid:

          (a) If to Schnell, at the address indicated on the signature page
     hereof.

          (b) If to the Corporation, to:

              MICROCIDE PHARMACEUTICALS, INC.
              850 Maude Avenue
              Mountain View, California 94043

or to such other address as may have been furnished to Schnell by the
Corporation.

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     17. This Agreement supercedes and terminates any previous agreement between
Schnell and the Corporation regarding the subject matter hereof.



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IN WITNESS WHEREOF, the parties hereto have executed this Agreement on and as of
the day and year first above written.

                                        MICROCIDE PHARMACEUTICALS, Inc.

                                        By:      /s/ John P. Walker
                                           ----------------------------
                                        Print Name:  John P. Walker
                                                    -------------------
                                        Title:       Chairman
                                              -------------------------


                                         /s/ David Schnell
                                        -------------------------------
                                             DAVID SCHNELL


                                        Address:  Prospect Management Co., LLC
                                                  ------------------------------
                                                  435 Taddio Street, Suite 200
                                                  ------------------------------
                                                  Palo Alto, CA 94301
                                                  ------------------------------



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