##### 



EXHIBIT 4.9
 First Amendment to  Amended and Restated Investor Rights Agreement
 This First Amendment to the Amended and Restated Investor Rights Agreement Amendment SGX
Pharmaceuticals, Inc. Company Series A Preferred Series B Preferred Original Parties
 Whereas, Investor Rights Agreement
 Whereas SVB Oxford Loan
Agreement
 Whereas
 Now, therefore
 1.
    
    Capitalized terms not defined herein shall have the meaning ascribed to them in the Investor
Rights Agreement.2.
    
    SVB and Oxford shall become parties to the Investor Rights Agreement and the definition of
Holder in Section 1 of the Investor Rights Agreement shall include SVB and Oxford; provided,
however, that neither SVB nor Oxford (nor any permitted transferee or assignee of SVB or
Oxford) shall be deemed a Holder for purposes of Section 2.2 or 2.4 of the Investor Rights
Agreement.3.
    
    The definition of Registrable Securities in Section 1.1 of the Investor Rights Agreement
shall be replaced in its entirety with the following:
 Registrable Securities mHoldings Millennium
Note
 1.




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provided, however,
 4.
    
    The definition of Shares in Section 1.1 of the Investor Rights Agreement shall be replaced
in its entirety with the following:
 Shares Exhibit A Exhibit A Warrant Securities
 5.
    
    The following definition shall be added to Section 1.1 of the Investor Rights Agreement
immediately following the definition of Initial Offering:
 Lender Warrants
 6.
    
    By executing this Amendment, each of SVB and Oxford agree to be bound by the provisions of
the Investor Rights Agreement, as amended by this Amendment (and as may be subsequently
amended from time to time), including without limitation the provisions of Section 2.13
thereof.7.
    
    This Amendment may be executed in any number of counterparts, each of which shall be an
original, but all of which together shall constitute one instrument. Except as specifically
amended by this Amendment, the terms and conditions of the Investor Rights Agreement shall
remain unchanged and in full force and effect. This Amendment shall be governed by and
construed in accordance with the laws of the State of California as applied to contracts among
California residents entered into and performed entirely within California.
 2.




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In Witness Whereof First Amendment to the Amended and Restated Investor Rights Agreement
 Company:
 SGX Pharmaceuticals, Inc.By:
    
    /s/ Michael GreyName:
    
    Michael GreyTitle:
    
    President and Chief Executive Officer
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:ALEXANDRIA REAL ESTATE EQUITIES, L.P.,a Delaware limited partnershipBy:
    
    ARE-QRS CORP.,a Maryland corporation, general partnerBy:
    
    /s/ Etsuko MasonEtsuko MasonVice President, Treasurer andAssistant Secretary
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
  Investors /
    
    Holders:Name :
    
    *By:
    
    /s/ Jeanne Larkin HenryPrint Name:
    
    Jeanne Larkin HenryTitle:
    
    Vice-President
 ATLAS VENTURE FUND III, L.P.ATLAS VENTURE ENTREPRENEURS FUND III, L.P.By:
    
    Atlas Venture Associates III, L.P.its general partnerBy:
    
    Atlas Venture Associates III, L.P.its general partnerATLAS VENTURE FUND IV, L.P.ATLAS VENTURE PARALLEL FUND IV  A, C.V.ATLAS VENTURE PARALLEL FUND IV  B, C.V.ATLAS VENTURE ENTREPRENEURS FUND IV, L.P.By:
    
    Atlas Venture Associates IV, L.P.its general partnerBy:
    
    Atlas Venture Associates IV, Inc.its general partner
   [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Bavp, L.P.By:
    
    /s/ Louis C. BockPrint Name:
    
    Louis C. BockTitle:
    
    Managing Director
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Caduceus Private Investments, LPBy:
    
    /s/ Eric A. BittelmanPrint Name:
    
    Eric A. BittelmanTitle:
    
    CFO, OrbiMed Capital LLC, General Partner
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Coleman Swenson Hoffman Booth IV L.P.By:
    
    Its General Partner,CSHB Ventures IV L.P.By:
    
    /s/ Larry H. Coleman

Its: General PartnerPrint Name:
    
    Larry H. ColemanTitle:
    
    General Partner
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Walter T. DecBy:
    
    /s/ Walter T. DecPrint Name:
    
    Walter T. DecTitle:
    
    Sir
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    /s/ Ken Dill Joland SchreursBy:Print Name:
    
    Ken Dill Joland SchreursTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Frederick FrankBy:
    
    /s/ Frederick FrankPrint Name:
    
    Frederick FrankTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    GC&H InvestmentsBy:
    
    /s/ John L. CardozaPrint Name:
    
    John L. CardozaTitle:
    
    Executive Partner
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :By:
    
    /s/ Wayne A. HendricksonPrint Name:
    
    Wayne A. HendricksonTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    C. S. HenneyBy:
    
    /s/ Christopher S. HenneyPrint Name:Title:
    
    Chairman
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    James M. HesboughBy:
    
    /s/ James M. HesboughPrint Name:Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    /s/ Barry HonigBy:Print Name:
    
    Barry H. HonigTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Index Venture Management SAon behalf ofIndex Employee Investment PlanBy:
    
    /s/ David RimerPrint Name:
    
    David RimerTitle:
    
    Director
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    /s/ Joshua LederbergBy:Print Name:Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Charles E. MatherBy:
    
    /s/ Charles E. MatherPrint Name:
    
    Charles E. MatherTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    K. Flynn McDonaldBy:
    
    /s/ K. Flynn McDonaldPrint Name:
    
    K. Flynn McDonaldTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :By:
    
    /s/ Stelios PapadopoulosPrint Name:
    
    Stelios PapadopoulosTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Prospect Venture Partners, L.P.By:
    
    /s/ Alex BarkasPrint Name:
    
    Alex BarkasTitle:
    
    Managing Member, ProspectManagement Co. LLC, generalpartner of Prospect VenturePartners, L.P.
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Peter ReikesBy:
    
    /s/ Peter ReikesPrint Name:
    
    Peter ReikesTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    George E. RossmannBy:
    
    /s/ George E. RossmannPrint Name:Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Rutter Investments, LPBy:
    
    /s/ William J. RutterPrint Name:
    
    William J. RutterTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    William J. RutterBy:
    
    /s/ William J. RutterPrint Name:
    
    William J. RutterTitle:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Name:
    
    William J. Rutter Revocable TrustBy:
    
    /s/ William J. Rutter
 Print Name:
    
    William J. Rutter
 Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    /s/ Andrej Sali
 By:
 Print Name:
 Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
 By:
    
    /s/ John P. Schmidt
 Print Name:
    
    John P. Schmidt
 Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Scinet Development & Holdings, Inc.
 By:
    
    /s/ John E. Lamier
 Print Name:
    
    John E. Lamier
 Title:
    
    President
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name:
    
    SGC Partners I LLC
 By:
    
    /s/ Christopher A. White
 Print Name:
    
    Christopher A. White
 Title:
    
    Director
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name:
    
    Spring Creek Partners
 By:
    
    /s/ Duane R. Bach
 Print Name:
    
    Duane R. Bach
 Title:
    
    GP
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:DLJ Capital Corporation/s/ Vijay K. LathiBy:
    
    Vijay K. LathiIts:
    
    Attorney in FactDLJ ESC II, L.P.By:
    
    DLJ LBO Plans Management CorporationIts:
    
    General Partner/s/ Vijay K. LathiBy:
    
    Vijay K. LathiIts:
    
    Attorney in FactSprout Capital VIII, L.P.By:
    
    DLJ Capital CorporationIts:
    
    Managing General Partner/s/ Vijay K. LathiBy:
    
    Vijay K. LathiIts:
    
    Attorney in FactSprout Plan Investors, L.P.By:
    
    DLJ LBO Plans Management Corporation IIIts:
    
    General Partner/s/ Vijay K. LathiBy:
    
    Vijay K. LathiIts:
    
    Attorney in Fact
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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Sprout Venture Capital, L.P.By:
    
    DLJ Capital CorporationIts:
    
    General Partner/s/ Vijay K. LathiBy:
    
    Vijay K. LathiIts:
    
    Attorney in Fact
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:VECTOR LATER-STAGE EQUITY FUND II, L.P.By:
    
    VECTOR FUND MANAGEMENT II, L.L.C.Its:
    
    General PartnerBy:
    
    /s/ Barclay A. PhillipsBarclay A. PhillipsIts:
    
    Managing Director
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:VECTOR LATER-STAGE EQUITY FUND I, (QP), L.P.By:
    
    VECTOR FUND MANAGEMENT II, L.L.C.Its:
    
    General PartnerBy:
    
    /s/ Barclay A. PhillipsBarclay A. PhillipsIts:
    
    Managing Director
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Name :
    
    Vulcan Ventures Inc.
 By:
    
    /s/ W. Lance Conn
 Print Name:
    
    W. Lance Conn
 Title:
    
    EVP, Investment Management
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the Amended and Restated Investor Rights Agreement
 Silicon Valley BankSignature:
    
    /s/ Susan L. Worsham
 Print Name:
    
    Susan L. Worsham
 Title: Deal Team Leader
 Oxford Finance CorporationSignature:
 Print Name:
 Title:
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof First Amendment to the Amended and Restated Investor Rights Agreement
 Silicon Valley BankSignature:
 Print Name:
 Title:
 Oxford Finance CorporationSignature:
    
    /s/ M.J. Altenburger
 Print Name: Michael J. Altenburger
 Title: Chief Financial Officer
 [Signature Page to First Amendment to Amended and Restated Investor Rights Agreement]




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Second Amendment to  Amended and Restated Investor Rights Agreement
 This Second Amendment to the Amended and Restated Investor Rights Agreement Amendment SGX
Pharmaceuticals, Inc. Company Original
Parties Novartis Pharma AG Novartis
 Whereas, Investor Rights Agreement
 Whereas,
 Whereas Purchase Agreement
 Whereas
 Now, therefore
 1.
    
    Capitalized terms not defined herein shall have the meaning ascribed to them in the Investor
Rights Agreement.
 2.
    
    The Company and the Original Parties holding the requisite 66-2/3% of the Registrable
Securities hereby agree to amend the Investor Rights Agreement as set forth in this Amendment,
and such Original Parties further hereby consent to and waive their rights under Section 2.12
of the Investor Rights Agreement and under any other applicable provision of the Investor
Rights Agreement with respect to the registration rights granted to Novartis as set forth
herein.
 3.
    
    Novartis shall become a party to the Investor Rights Agreement and the definition of Holder
in Section 1 of the Investor Rights Agreement shall include Novartis, for all purposes under
the Investor Rights Agreement.
 4.
    
    The definition of Registrable Securities in Section 1.1 of the Investor Rights Agreement
shall be replaced in its entirety with the following:
 Registrable Securities
 1




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mHoldings Millennium Note provided, however, Novartis Shares Novartis
 5.
    
    The word and number ninety (90) set forth in Section 2.4(c) of the Investor Rights
Agreement are hereby deleted in their entirety and replaced with the word and number sixty
(60).
 6.
    
    Section 2.6(a) of the Investor Rights Agreement is hereby deleted and replaced in its
entirety with the following:
  7.
    
    A new sentence is hereby added before the last sentence of Section 2.11 of the Investor
Rights Agreement which reads as follows:
 provided, however,
 8.
    
    A new subsection 5.6(e) of the Investor Rights Agreement is hereby added which reads as
follows:
 2




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provided, however,
 9.
    
    By executing this Amendment, Novartis agrees to be bound by the provisions of the Investor
Rights Agreement, as amended by this Amendment (and as may be subsequently amended from time
to time, subject to Section 5.6(e)), including without limitation the provisions of Section
2.13 thereof.10.
    
    Notwithstanding Section 2.7 of the Investor Rights Agreement, all registration rights granted
to Novartis under Section 2 of the Investor Rights Agreement shall terminate and be of no
further force and effect at the earlier of (a) five (5) years after the date of the Companys
Initial Offering or (b) after the Companys Initial Offering, at such time as (i) Novartis is
entitled to sell all of its shares pursuant to SEC Rule 144(k) and (ii) Novartis owns less
than one percent (1%) of the Registrable Securities.
 11.
    
    The Company hereby acknowledges that, as a result of the 1-for-2 reverse stock split of the
Companys Common Stock effected in January 2005, the number of shares of Registrable
Securities set forth in Section 2.10 of the Investor Rights Agreement is equal to 6,322 shares
of Registrable Securities as of the date hereof.
 12.
    
    Notwithstanding Section 5.8 of the Investor Rights Agreement, all notices to Novartis
required or permitted hereunder or under the Investor Rights Agreement shall be in writing and
shall be deemed effectively given: (a) upon personal delivery to Novartis; (b) when sent by
confirmed electronic mail or facsimile if sent during normal business hours of the recipient;
if not, then on the next business day; (c) five (5) days after having been sent by registered
or certified mail, return receipt requested, postage prepaid; or (d) three (3) days after
deposit with a nationally recognized overnight courier, specifying next or two-day delivery,
with written verification of receipt. All communications to Novartis shall be sent to the
address as set forth on the signature pages hereof or at such other address as Novartis may
designate by ten (10) days advance written notice to the Company.
 13.
    
    This Amendment may be executed in any number of counterparts, each of which shall be an
original, but all of which together shall constitute one instrument. Except as specifically
amended by this Amendment, the terms and conditions of the Investor Rights Agreement shall
remain unchanged and in full force and effect. This Amendment shall be governed by and
construed in accordance with the laws of the State of California as applied to contracts among
California residents entered into and performed entirely within California.
 3




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In Witness Whereof Second Amendment to the Amended and Restated Investor Rights Agreement
 Company:SGX Pharmaceuticals, Inc.By:
    
    /s/ Michael GreyName:
    
    M G GreyTitle:
    
    President and CEO
 [Signature Page
 to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Novartis Pharma AGSignature:
/s/ Joseph E.
Mamie
    
    Signature: /s/ Dr. Matthias
S.
RungePrint Name: Joseph E. Mamie
    
    Print Name: Dr. Matthias S. RungeTitle: Head Operational Treasury
    
    Title: Head Legal Pharma Ophthalmics &Oncology Region Europe
 Address:
 [Signature
Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to the
Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name: Millennium Pharmaceuticals,
Inc.By: /s/ Joel GoldbergPrint Name: Joel GoldbergTitle: Assoc. General Counsel
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity Name:
    
    ATLAS VENTURE FUND III, L.P.ATLAS VENTURE
ENTREPRENEURS FUND III, L.P.By:
    
    Atlas Venture Associates III, L.P.its general partnerBy:
    
    Atlas Venture Associates III, L.P.its general partnerBy:
/s/ Axel
BichamPrint Name: Axel BichamTitle:ATLAS VENTURE FUND IV, L.P.ATLAS VENTURE PARALLEL
FUND IV  A, C.V.ATLAS VENTURE
ENTREPRENEURS FUND IV, L.P.By:
    
    Atlas Venture Associates IV, L.P.its general partnerBy:
    
    Atlas Venture Associates IV, Inc.its general partner
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity Name: BAVP, L.P.By:
/s/ Louis C.
BockPrint Name: Louis C. BockTitle: Managing Director
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name: Sprout Capital VIII,
L.P.SPROUT CAPITAL VIII, L.P.By:
    
    DLJ Capital CorporationIts:
    
    Managing General PartnerBy:
    
    /s/ Vijay K.
LathiVijay K. LathiAttorney in Fact
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name: Sprout Venture Capital,
L.P.SPROUT VENTURE CAPITAL, L.P.By:
    
    DLJ Capital CorporationIts:
    
    General PartnerBy:
    
    /s/ Vijay K.
LathiVijay K. LathiAttorney in Fact
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name: Sprout Plan Investors,
L.P.SPROUT PLAN INVESTORS, L.P.By:
    
    DLJ LBO Plans Management Corporation IIIts:
    
    General PartnerBy:
    
    /s/ Vijay K.
LathiVijay K. LathiAttorney in Fact
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name : DLJ ESC II,
L.P.DLJ ESC II, L.P.By:
    
    DLJ LBO Plans Management CorporationIts:
    
    General PartnerBy:
    
    /s/ Vijay K. LathiVijay K. LathiAttorney in Fact
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity
Name : DLJ Capital
CorporationDLJ CAPITAL CORPORATIONBy:
    
    /s/ Vijay K. LathiVijay K. LathiAttorney in Fact
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:Entity Name :
 By:
/s/ Alex
BarkasPrint Name: Alex BarkasTitle: Managing Member of the General Partner ofProspect Venture Partners
 [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:
 Entity Name : Index venture Associates I Limited As General Partner of
 Index Ventures I (jersey) L.P.  Index Ventures I (Delaware) L.P.  Index Ventures I Parallel Entrepreneur Fund (Jersey) L.P.
 Index Ventures I (SLP) Limited As General Partner of
 Index Ventures I GMBH & co KG
 /s/ Kate Wilson
   [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]




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In Witness Whereof Second Amendment to
the Amended and Restated Investor Rights Agreement
 Investors/Holders:
 Entity Name : Index Venture Management SA
 /s/
Neil Rimer/Nunu
Tadesse
   [Signature Page to Second Amendment to Amended and Restated Investor Rights Agreement]