**Exhibit 10.15.2**FIRST AMENDMENT TO LEASE     THIS FIRST AMENDMENT TO LEASE dated as of this 29th day of June, 2007by and between BOSTON PROPERTIES LIMITED PARTNERSHIP, a Delaware limited partnership (“Landlord”)and PAREXEL INTERNATIONAL LLC, a Delaware limited liability company (as successor-in-interest toParexel International Corporation “Tenant”).RECITALS     WHEREAS, by lease dated November 17, 1998 (as amended by the letter agreement described below,the “Lease”) Landlord did lease to Tenant and Tenant did hire and lease from Landlord certainpremises containing 129,199 square feet of rentable floor area (the “Rentable Floor Area of theInitial Premises”) in the building (the “Building”) known as and numbered 200 West Street, Waltham,Massachusetts (referred to in the Lease as the “Premises” or “Tenant’s Space” and hereinaftersometimes referred to as the “Initial Premises”).     WHEREAS, Landlord and Tenant entered into a certain letter agreement dated June 15, 2001regarding Tenant’s leasing of an additional 18,545 square feet of rentable floor area (the“Rentable Floor Area of the Expansion Premises”) located on the first (1st) floor of theBuilding (the “Expansion Premises”) pursuant to Section 2.1.3 of the Lease. The Initial Premisesand the Expansion Premises are hereinafter referred to collectively as the “Existing Premises” andthe Rentable Floor Area of die Initial Premises and the Rentable Floor Area of the ExpansionPremises are hereinafter referred to collectively as the “Rentable Floor Area of the ExistingPremises.”     WHEREAS, on or about the date hereof, Landlord and Tenant have executed or will execute acertain lease amendment (the “195 West Street Lease Amendment”) with respect to Tenant’s existingpremises in the building known as and numbered 195 West Street, Waltham, Massachusetts (the “195West Street Premises”).     WHEREAS, to provide Tenant with a period of time within which to complete certain tenantimprovements in the 195 West Street Premises, Landlord and Tenant have agreed to extend the Term ofthe Lease upon all of the same terms and conditions set forth in the Lease except as set forth inthis First Amendment to Lease (the “First Amendment”).     WHEREAS, Tenant has requested that Landlord reduce the size of the Existing Premises duringthe extension period described in the immediately preceding paragraph by subtracting therefrom the56,494 square feet of rentable floor area (the “Rentable Floor Area of the Relinquished Premises”)shown on Exhibit A attached hereto as the relinquished premises (the “Relinquished Premises”) sothat the remaining space demised to Tenant under the Lease shall be the 91,250 square feet ofrentable floor area (the “Rentable Floor Area of the Remaining Premises”) shown on said Exhibit Aas the remaining premises (the “Remaining Premises”).
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     Landlord and Tenant are entering into this instrument to set forth said agreement to extendthe Term of the Lease, to reduce the size of the Existing Premises and to further amend the Lease.     NOW,THEREFORE, in consideration of One Dollar ($1.00) and other good and valuableconsideration in hand this date paid by each of the parties to the other, the receipt andsufficiency of which are hereby severally acknowledged, and in further consideration of the mutualpromises herein contained, Landlord and Tenant hereby agree to and with each other as follows:     1. (a) The Term of the Lease, which but for this First Amendment is scheduled toexpire on April 30, 2009, is hereby extended for a period commencing on May 1, 2009 and expiring onAugust 31, 2009 (the “Extended Term”), unless sooner terminated in accordance with the provisions ofthe Lease or extended pursuant to the provisions of subsection (b) below, upon all the same termsand conditions contained in the Lease as herein amended.          (b) Notwithstanding the foregoing, in the event that Landlord has not provided Tenantwith written notice that it has “substantially completed” (as that term is defined in Section 8(C)of the 195 West Street Lease Amendment) the components of the Base Building Work (as that term isdefined in Section 8(A) of the 195 West Street Lease Amendment) described under the headings “HVACSystem,” “BuildingFaVade” and “Main Exterior Building Entrance” in Exhibit C to the 195 WestStreet Lease Amendment (such components being hereinafter referred to collectively as the “195 WestStreet Landlord’s Work”) on or before August 1, 2009, the Extended Term shall expire on the datethat is thirty (30) days after the date on which Landlord has provided Tenant with such notice thatthe 195 West Street Landlord’s Work has been substantially completed; provided, however, that: (i) If the 195 West Street Landlord’s Workhas not been substantially completed on or before August 1, 2009 otherthan as the result of (x) events beyond Landlord’s reasonable controlor (y) any act or wrongful failure to act of Tenant which interfereswith Landlord’s completion of the 195 West Street Landlord’s Work(including, without limitation, Tenant’s use of non-union labor inconnection with the construction of the Tenant Improvement Work, asthat term is defined in the 195 West Street Lease Amendment), Tenantshall not be required to pay any Annual Fixed Rent, Operating ExpensesAllocable to the Premises or Landlord’s Tax Expenses Allocable to thePremises under the Lease for the period commencing on September 1, 2009through the expiration of the Extended Term.  (ii) If the 195 West Street Landlord’s Work hasnot been substantially completed on or before August 1, 2009 as theresult of (x) events beyond Landlord’s reasonable control or (y) any actor wrongful failure to act of Tenant which interferes with Landlord’s
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   completion of the 195 West Street Landlord’s Work (including,without limitation, Tenant’s use of non-union labor in connectionwith the construction of the Tenant Improvement Work), Annual FixedRent, Operating Expenses Allocable to the Premises and Landlord’sTax Expenses Allocable to the Premises shall continue to be payableby Tenant for the period commencing on September 1, 2009 through theexpiration of the Extended Term as set forth in Section 5 below.It is understood and agreed that the provisions of this Section l(b) shall not be deemed to in anyway modify the provisions of the 195 West Street Lease Amendment relating to the completion of theBase Building Work by Landlord or the payment of annual fixed rent by Tenant with respect to the195 West Street Premises.     2. Landlord and Tenant acknowledge and agree that the extension options contained in Section2.4.1 of the Lease shall be deleted in their entirety and Tenant shall have no further option toextend the Term upon the expiration of the Extended Term.     3. As of May 1, 2009 (the “Reduction Date”), the Relinquished Premises shall be deleted fromthe space demised from Landlord to Tenant under the Lease, so that the remaining space demisedunder the Lease shall consist of the Remaining Premises and the term “Premises” as used in theLease shall thereafter be deemed to refer to the Remaining Premises only.     4. On or prior to the Reduction Date, Tenant shall quit and vacate the Relinquished Premisesand surrender same in the condition required by the Lease upon the expiration or earliertermination of the Lease Term.     5. (a) For the portion of the Lease Term prior to the Reduction Date, Tenant shallcontinue to pay Annual Fixed Rent as provided in the Lease.          (b) For the period on and after the Reduction Date, Annual Fixed Rent shall be payableby Tenant for the Remaining Premises at the annual rate of $3,011,250.00 (being the product of (i)$33.00 and (ii) the Rentable Floor Area of the Remaining Premises (being 91,250 square feet)).     6. For the purpose of computing Operating Expenses Allocable to the Premises pursuant toSection 2.6 of the Lease, Landlord’s Tax Expenses Allocable to the Premises pursuant to Section2.7 of the Lease and Tenant’s payments for electricity (as determined pursuant to Sections 2.5 and2.8 of the Lease), for the portion of the Lease Term on and after the Reduction Date, the“Rentable Floor Area of the Premises” shall be reduced by the Rentable Floor Area of theRelinquished Premises (being 56,494 square feet) to become the Rentable Floor Area of theRemaining Premises (being 91,250 square feet). For the portion of the Lease Term prior to theReduction Date, the “Rentable Floor Area of the Premises” shall continue to be the Rentable FloorArea of the Existing Premises for such purposes.     7. Section 2.1.3 of the Lease is hereby deleted in its entirety, it beingacknowledged
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and agreed that the Expansion Premises has previously been delivered to Tenant.     8. Effective as of the Reduction Date, the second grammatical paragraph of Section 2.7 of the Lease shall be deleted from the Lease in its entirety and shall be null and void and ofno further force and effect.     9. Effectiveas of the Reduction Date, Section 4.6 of the Lease shall be deleted from theLease in its entirety and shall be null and void and of no further force and effect.     10. Effective as of the Reduction Date, Section 8.22 of the Lease shall be deleted from theLease in its entirety and shall be null and void and of no further force and effect, it beingunderstood and agreed that (x) Tenant shall have the exclusive right to use the ground floor levelof the Parking Structure during the Extended Term (such parking rights being hereinafter referredto as “Tenant’s Exclusive Parking”), (y) Tenant shall have the right to use the remainder of theParking Structure in common with other occupants of the Building, subject to Landlord’s reasonablerules and regulations regarding such use (including, without limitation, Landlord’s right toprovide other Building occupants with exclusive parking rights within the Parking Structure) and(z) the Number of Parking Spaces to which Tenant shall be entitled under Sections 1.1 and 2.2.1 ofthe Lease shall be reduced to Three Hundred Forty-Seven (347) (being3.8 spaces per 1,000 square feet of the Rentable Floor Area of the Remaining Premises), whichnumber shall not include Tenant’s Exclusive Parking but shall include both surface parking andparking in the remainder of the Parking Structure (to the extent the same is not reserved for theexclusive use of any other Building occupants).Landlord shall not grant to anyone other than Tenant the right to use Tenant’s Exclusive Parkingand will use reasonable efforts, by the use of signs and markings, to designate such space to beused exclusively by Tenant, however, Landlord shall not be otherwise obligated to police the use ofTenant’s Exclusive Parking, which Tenant recognizes is to be operated on a self parking basis.In addition, it is understood and agreed that the parking rights described in this Section 10shall be provided to Tenant free of charge during the Extended Term.     11. All capitalized terms used herein shall have the same meaning as are set forth in theLease unless specifically otherwise provided herein.     12. Except as herein amended the Lease shall remain unchanged and in full force and effect.All references to the “Lease” shall be deemed to be references to the Lease as herein amended.[page ends here]
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EXECUTED as a sealed instrument as of the date and year first above written.       WITNESS: LANDLORD:         BOSTON PROPERTIES LIMITED  PARTNERSHIP,              By: BOSTON PROPERTIES, INC.,    its general partner           By:             Name:             Title:                TENANT:       PAREXEL INTERNATIONAL LLC       By:         Name:         Title: (President or Vice President)              Hereto duly authorized       ATTEST:      By: /s/ W. Brett Davis By: /s/ James F. Winschel Jr.       Name: W. Brett Davis Name: JAMES F. WINSCHEL, JR.Title: (Assistant Secretary) Title: (Treasurer)                Hereto duly authorized             (CORPORATE SEAL)
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