Exhibit 10.53**THIRD AMENDMENT TO LEASE**          **THIS THIRD AMENDMENT TO LEASE**(this “**Amendment**”) is made and entered into as of July 18, 2007,by and between **RREEF AMERICA REIT II CORP. FFF, a Maryland corporation**(“**Landlord**”), and **AVANIRPHARMACEUTICALS, a California corporation**(“**Tenant**”).**RECITALS**A. Landlord and Tenant are parties to that certain Lease, dated April 28, 2006 (the “**OriginalLease**”), which Original Lease has been previously amended by that certain First Amendment toLease, dated December 14, 2006, and that certain Second Amendment to Lease, dated March 13,2007 (collectively, the “**Lease**”). Pursuant to the Lease, Landlord has leased to Tenant spacecurrently containing approximately **17,609**rentable square feet (the “**Original Premises**”)described as Suite No. 300A and 300B (collectively, “**Suite 300**”) and Suite 320 (“**Suite 320**”,together with Suite 300, the “**Initial Premises**”) and Suites 330 and 335 (collectively, the“**Additional Premises**”) on the third floor of the building located at 101 Enterprise, AlisoViejo, California (the “**Building**”). B. Tenant desires to surrender to Landlord the Additional Premises containing approximately**6,290**rentable square feet described as Suite No. 330 (“**Suite 330**”) and Suite No. 335 (“**Suite335**”) of the Building as shown on **Exhibit A**hereto (collectively, the “**Reduction Space**”) (theOriginal Premises, less the Reduction Space, is referred to herein as the “**RemainingPremises**”) and that the Lease be appropriately amended, and Landlord is willing to accept suchsurrender on the following terms and conditions.          **NOW, THEREFORE,**in consideration of the mutual covenants and agreements herein contained andother good and valuable consideration, the receipt and sufficiency of which are herebyacknowledged, Landlord and Tenant agree as follows:1. **Reduction.** 1.1 Tenant shall vacate the Reduction Space in accordance with the terms of theLease on or prior to July 31, 2007, which is the date immediately preceding theReduction Effective Date (defined in 1.2 below) and, except as expressly set forth inthis Section 1.1, Tenant shall fully comply with all obligations under the Leaserespecting the Reduction Space up to the Reduction Effective Date, including thoseprovisions relating to the condition of the Reduction Space and removal of Tenant’sProperty therefrom; provided however, Landlord and Tenant hereby acknowledge that as ofthe date hereof, notwithstanding the applicable Additional Premises Commencement Dateswith respect to Suite 300 and Suite 335 (as more particularly described in the firstsentence of Section 2 below), Tenant has never physically occupied the Reduction Spaceand therefore shall not have any obligation to remove any personal property, equipmentor fixtures from the Reduction Space or to restore the Reduction Space. Tenant herebyagrees that Tenant shall have no right to enter or occupy the Reduction Space at anytime and, accordingly, Tenant shall return all keys to the Reduction Space and shalldeliver possession of the Reduction Space to Landlord upon Tenant’s execution hereof.  1.2 Effective as of August 1, 2007 (the “**Reduction Effective Date**”), the Premisesis decreased from approximately 17,609 rentable square feet of the Building toapproximately **11,319**rentable square feet comprised of Suite 300 and Suite 320 of theBuilding by the elimination of the Reduction Space, and the number of unreservedparking spaces available to Tenant
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   shall be proportionately reduced. As of the Reduction Effective Date, the ReductionSpace shall be deemed surrendered by Tenant to Landlord, the Lease shall be deemedterminated with respect to the Reduction Space, and the “Premises”, as defined inthe Lease and as used herein shall be deemed to mean the Remaining Premises;provided, if Tenant shall violate any provision hereof or if Tenant’srepresentations herein shall be false or materially misleading, Landlord shall havethe right to declare this Amendment null and void and to reinstate the Lease withrespect to the Reduction Space in addition to, and not in lieu of, any other rightsor remedies available to Landlord.  1.3 If Tenant shall holdover in the Reduction Space beyond the day immediatelypreceding the Reduction Effective Date, Tenant shall be liable for Monthly Installmentof Rent, Tenant’s Proportionate Share of Expenses, Insurance Costs and Taxes and othercharges respecting the Reduction Space equal to 150% of the amount in effect under theLease prorated on a per diem basis and on a per square foot basis for the ReductionSpace. Such holdover amount shall not be in limitation of Tenant’s liability fordamages arising from Tenant’s holding over nor shall it be deemed permission for Tenantto holdover in the Reduction Space. If, as a result of Tenant’s holding over, Landlordshall install a wall separating the Reduction Space from the balance of the Premises orotherwise incur expense in installing separate utility meters or effecting similarseparations, Tenant, upon demand, shall reimburse Landlord’s costs in connectiontherewith.2. **Monthly Installment of Rent.** Tenant hereby acknowledges and agrees that (a) theAdditional Premises Commencement Date with respect to Suite 335 occurred on April 15, 2007 andthe Additional Premises Commencement Date with respect to Suite 330 occurred on July 1, 2007;and (b) Tenant shall pay Monthly Installment of Rent and Tenant’s Proportionate Share ofExpenses, Taxes and Insurance Costs with respect to Suite 335 and Suite 330 for the periodbeginning on the applicable Additional Premises Commencement Date and ending on the ReductionEffective Date. Concurrently with Tenant’s execution of this Amendment, Tenant shall deliverto Landlord an amount equal to $26,091.60, representing the Monthly Installment of Rent owedwith respect to the Suite 335 for the months (or applicable portion thereof) of April, May,June and July of 2007 and with respect to Suite 330 for the month of July of 2007. Tenantshall remain liable, subject to and in accordance with the terms of the Lease, for the paymentof Tenant’s Proportionate Share of Expenses, Taxes and Insurance Costs with respect to theAdditional Premises accruing prior to the Reduction Effective Date. Effective as of theReduction Effective Date, the schedule of Monthly Installment of Rent contained in the Leaseis deleted, and the following is substituted therefor:                     **Rentable** **Annual Rate**     **Monthly**   **Square** **Per Square**     **Installment of****Period**  **Footage** **Foot** **Annual Rent** **Rent**  7/1/07 – 7/9/07   11,319  $31.80  $359,944.20  $29,995.35 7/10/07 – 7/9/08   11,319  $32.75  $370,697.25  $30,891.44 7/10/08 – 7/9/09   11,319  $33.73  $381,789.87  $31,815.82 7/10/09 – 7/9/10   11,319  $34.74  $393,222.06  $32,768.51 7/10/10 – 7/9/11   11,319  $35.78  $404,993.82  $33,749.49   All such Monthly Installment of Rent shall be payable by Tenant in accordance with the termsof the Lease, as amended hereby. 3. **Additional Security Deposit.** No additional Security Deposit shall be required inconnection with this Amendment. Notwithstanding the foregoing, and provided that, during thetwelve (12) month
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  period immediately preceding the effective date of any reduction of the Security Deposit,Tenant has timely paid all Monthly Installments of Rent, Tenant’s Proportionate Share ofExpenses and Taxes and all other sums and charges payable under this Lease and no defaulthas occurred under this Lease (the “Security Reduction Conditions”), Tenant shall have theright to reduce the amount of the Security Deposit so that the new Security Deposit amountwill be as follows: $37,124.65 effective as of August 1, 2008. If Tenant is entitled to areduction in the Security Deposit, Tenant shall provide Landlord with written notice on orbefore June 15, 2008 requesting that the Security Deposit be reduced as provided above (the“Security Reduction Notice”). If Tenant provides Landlord with a Security Reduction Notice,and Tenant is entitled to reduce the Security Deposit as provided herein, Landlord shallrefund the applicable portion of the Security Deposit to Tenant within forty-five (45) daysafter the later to occur of (a) Landlord’s receipt of the Security Reduction Notice, or (b)the date upon which Tenant is entitled to a reduction in the Security Deposit as providedabove. 4. **Additional Consideration.** As additional consideration for this Amendment, Tenantagrees to pay Landlord upon the Reduction Effective Date: (a) with respect to Suite 330, anamount equal to $63,187.45, plus the Additional Amount (as defined below), and (b) withrespect to Suite 335, an amount equal to $10,350.39. As used herein, “Additional Amount”means an amount equal to the rent (i.e., monthly installments of rent plus tenant’sproportionate share of expenses, insurance costs and taxes) due and payable by Barney (asdefined in Section 10 below), as tenant, under the Barney Lease (as defined in Section 10below) with respect to the period beginning on the Substitution Effective Date (as defined inthe Barney Amendment (as defined in Section 10 below)) and ending on January 31, 2008;provided, however, that in no event shall the Additional Amount exceed $42,185.00, whichLandlord represents is the sum of five (5) months of monthly installment of rent payable byBarney pursuant to the terms of the Barney Lease (and Landlord shall provide to Tenant aninvoice showing such amount). 5. **Tenant’s Proportionate Share.** For the period commencing on the Reduction EffectiveDate and ending on the Termination Date, Tenant’s Proportionate Share of the Building forExpenses and Insurance Costs is **14.13%**, and Tenant’s Proportionate Share of the Building forTaxes is **6.71%**Notwithstanding anything in this Amendment to the contrary, Tenant shallremain liable for all year-end adjustments with respect to Tenant’s Proportionate Share ofExpenses, Insurance Costs and Taxes applicable to the Reduction Space for that portion of thecalendar year commencing on the applicable Additional Premises Commencement Date and ending onthe Reduction Effective Date for each of Suites 330 and 335, respectively. Such adjustmentsshall be paid at the time, in the manner and otherwise in accordance with the terms of theLease, unless otherwise specified herein. 6. **Expenses, Insurance Costs and Taxes.** For the period commencing on the ReductionEffective Date and ending on the Termination Date, Tenant shall pay for Tenant’s ProportionateShare of Expenses, Insurance Costs, and Taxes in accordance with the terms of the Lease. 7. **Improvements to Remaining Premises.** 7.1 **Condition of Remaining Premises.**Tenant is in possession of the RemainingPremises and agrees to accept the same “as is” without any agreements, representations,understandings or obligations on the part of Landlord to perform any alterations,repairs or improvements, except as may be expressly provided otherwise in thisAmendment. Tenant hereby acknowledges and agrees that, effective as of the datehereof, Tenant is not entitled to the Additional Premises Maximum Amount (as defined inExhibit B to the Original Lease) or any portion thereof, and such Additional PremisesMaximum Amount has been, in effect,
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   credited to Tenant as reflected in the calculation of the consideration owed byTenant pursuant to the terms of Section 4 above.  7.2 **Responsibility for Improvements to Remaining Premises.**Any construction,alterations or improvements to the Remaining Premises shall be performed by Tenant atits sole cost and expense using contractors selected by Tenant and approved by Landlordand shall be governed in all respects by the provisions of Article 6 of the OriginalLease.8. **Representations.** Each party represents to the other that it has full power andauthority to execute this Amendment. Tenant represents that it has not made any assignment,sublease, transfer, conveyance of the Lease or any interest therein or in the Reduction Spaceother than those explicitly recited herein and further represents that there is not and willnot hereafter be any claim, demand, obligation, liability, action or cause of action by anyother party claiming through Tenant respecting, relating to or arising out of the ReductionSpace, and Tenant agrees to indemnify and hold harmless Landlord and the Landlord RelatedParties (as defined in Section 11.6 below) from all liabilities, expenses, claims, demands,judgments, damages or costs arising from any of the same, including without limitation,attorneys’ fees. Tenant acknowledges that Landlord will be relying on this Amendment inentering into leases for the Reduction Space with other parties. 9. **Other Pertinent Provisions.** Landlord and Tenant agree that, effective as of the dateof this Amendment (unless different effective date(s) is/are specifically referenced in thisSection), the Lease shall be amended in the following additional respects: 9.1 **Additional Premises References**. Effective as of the Reduction Effective Date,any references in the Original Lease to the “Additional Premises” or the “AdditionalPremises Commencement Date” are hereby deleted in their entirety.  9.2 **Monument Signage**. Article 45 (Monument Signage) is hereby deleted in its entirety.  9.3 **Right of First Offer**. The first sentence of Section 41.1 of the Lease ishereby deleted in its entirety and replaced with the following: “Tenant shall have theon-going right of offer (the “Offer Right”) to lease space located on the third(3rd) floor of the Building (“Offer Space”), provided that said space is notalready encumbered by options of existing tenants at the Building, effective at suchtime as the subject Offer Space is vacated by the prior tenant (or, if the prior tenanthas confirmed in writing that tenant will not extend or renew its lease prior tovacating the Offer Space, upon such time as Landlord receives such writtenconfirmation).”10. **Contingencies.** This Amendment, as it relates to Suite 330, specifically iscontingent upon the modification of that certain Lease, dated December 20, 2005 (the “**BarneyLease**”), by and between Landlord and Barney & Barney, LLC, a California limited liabilitycompany (“**Barney**”). This Amendment, as it relates to Suite 335, specifically is contingentupon the modification of that certain Lease, dated January 18, 2006 (the “**NCSoft Lease**”), byand between Landlord and NCSoft Corporation, a Korean corporation (“**NCSoft**”). Landlordcurrently is negotiating the terms of an agreement with Barney to amend the Barney Lease (the“**Barney Amendment**”) to relocate Barney to Suite 330, and Landlord currently is negotiating theterms of an agreement with NCSoft to amend the NCSoft Lease (the “**NCSoft Amendment**”) to expandthe premises leased thereunder to include Suite 335. Landlord and Tenant agree that theforegoing contingencies are independent of each other. For the avoidance of doubt, thisAmendment shall be effective (a) with respect to Suite 330 if an acceptable Barney Amendmentis executed by Landlord and Barney on or before the Contingency Date (as defined below), and(b) with respect to Suite 335, if an acceptable NCSoft Amendment is
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  executed by Landlord and NCSoft on or before the Contingency Date. If Landlord fails toenter into the Barney Amendment with Barney and/or the NCSoft Amendment with NCSoft in formand substance satisfactory to Landlord on or before the date (the “**Contingency Date**”) thatis the later of (i) July 20, 2007, or (ii) five (5) days following the date this Amendment,executed by Tenant, is delivered to Landlord, then Landlord may terminate this Amendment (orrelevant portions thereof) by providing written notice thereof to Tenant, and Landlord andTenant shall enter into an amendment or other agreement to document any necessary revisionsrelated thereto (i.e., changes to the rent chart reflecting Monthly Installment of Rent,Tenant’s Proportionate Share, etc.). 11. **Miscellaneous.** 11.1 This Amendment, including **Exhibit A**(Outline and Location of Reduction Space)attached hereto, sets forth the entire agreement between the parties with respect tothe matters set forth herein. There have been no additional oral or writtenrepresentations or agreements. Under no circumstances shall Tenant be entitled to anyrent abatement, improvement allowance, leasehold improvements, or other work to thePremises, or any similar economic incentives that may have been provided Tenant inconnection with entering into the Lease, unless specifically set forth in thisAmendment. This Amendment shall not be relied upon by any other party, individual,corporation, partnership or entity as a basis for reducing its lease obligations withLandlord or for any other purpose. Tenant agrees that it shall not disclose anymatters set forth in this Amendment or disseminate or distribute any informationconcerning the terms, details or conditions hereof to any person, firm or entitywithout obtaining the express written consent of Landlord.  11.2 Except as herein modified or amended, the provisions, conditions and terms ofthe Lease shall remain unchanged and in full force and effect.  11.3 In the case of any inconsistency between the provisions of the Lease and thisAmendment, the provisions of this Amendment shall govern and control.  11.4 Submission of this Amendment by Landlord is not an offer to enter into thisAmendment but rather is a solicitation for such an offer by Tenant. Landlord shall notbe bound by this Amendment until Landlord has executed and delivered the same toTenant.  11.5 The capitalized terms used in this Amendment shall have the same definitions asset forth in the Lease to the extent that such capitalized terms are defined thereinand not redefined in this Amendment.  11.6 Tenant hereby represents to Landlord that Tenant has dealt with no broker inconnection with this Amendment. Tenant agrees to indemnify and hold Landlord, itsmembers, principals, beneficiaries, partners, officers, directors, employees,representatives, mortgagee(s) and agents, and the respective principals and members ofany such agents (collectively, the “**Landlord Related Parties**”) harmless from all claimsof any brokers claiming to have represented Tenant in connection with this Amendment.Landlord hereby represents to Tenant that Landlord has dealt with no broker inconnection with this Amendment. Landlord agrees to indemnify and hold Tenant, itsofficers, directors, shareholders, employees, representatives and agents harmless fromall claims of any brokers claiming to have represented Landlord in connection with thisAmendment.  11.7 Each signatory of this Amendment represents hereby that he or she has theauthority to execute and deliver the same on behalf of the party hereto for which suchsignatory is acting.
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   Tenant hereby represents and warrants that neither Tenant, nor any persons orentities holding any legal or beneficial interest whatsoever in Tenant, are (i) thetarget of any sanctions program that is established by Executive Order of thePresident or published by the Office of Foreign Assets Control, U.S. Department ofthe Treasury (“**OFAC**”); (ii) designated by the President or OFAC pursuant to theTrading with the Enemy Act, 50 U.S.C. App. § 5, the International EmergencyEconomic Powers Act, 50 U.S.C. §§ 1701-06, the Patriot Act, Public Law 107-56,Executive Order 13224 (September 23, 2001) or any Executive Order of the Presidentissued pursuant to such statutes; or (iii) named on the following list that ispublished by OFAC: “List of Specially Designated Nationals and Blocked Persons.” Ifthe foregoing representation is untrue at any time during the Term, an Event ofDefault under the Lease will be deemed to have occurred, without the necessity ofnotice to Tenant.**[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]**
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 11.8 Redress for any claim against Landlord under the Lease and this Amendment shallbe limited to and enforceable only against and to the extent of Landlord’s interest inthe Property. The obligations of Landlord under the Lease are not intended to andshall not be personally binding on, nor shall any resort be had to the privateproperties of, any of its trustees or board of directors and officers, as the case maybe, its investment manager, the general partners thereof, or any beneficiaries,stockholders, employees, or agents of Landlord or the investment manager.          **IN WITNESS WHEREOF**, Landlord and Tenant have duly executed this Amendment as of the day andyear first above written.           **LANDLORD:** **TENANT:**           **RREEF AMERICA REIT II CORP. FFF,**