Exhibit 10.13




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SECTION
    
    PAGERECITALS
    
    
    1AGREEMENTS
    
    
    2
 
 Section 1.1 Definitions
    
    
    2Section 1.2 Rules of Construction
    
    
    9
 
 Section 2.1 Effective Date of Reimbursement Agreement; Duration of Term
    
    
    9
 
 Section 3.1 Reimbursement and Other Payments
    
    
    10Section 3.2 Payments due Upon Expiration of Letter of Credit
    
    
    12Section 3.3 Late Payments
    
    
    13Section 3.4 Increased Costs Due to Change in Law
    
    
    13Section 3.5 Computation
    
    
    14Section 3.6 Payment Procedure
    
    
    14Section 3.7 Business Days
    
    
    14
 
 Section 4.1 Obligations Absolute
    
    
    14
 
 Section 5.1 Representations, Warranties and Undertakings
    
    
    15
 
 Section 6.1 Affirmative Covenants of Lessee
    
    
    16
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Section 7.1 Indemnification of Bank
    
    
    17Section 7.2 Indemnification Under Letters of Credit and Letter of Credit Agreements
    
    
    18
 
 Section 8.1 Events of Default Defined
    
    
    18Section 8.2 Remedies on Default
    
    
    20Section 8.3 No Remedy Exclusive
    
    
    21Section 8.4 Agreement to Pay Attorneys Fees and Expenses
    
    
    22Section 8.5 Waiver of Event of Default; No Additional Waiver Implied by One Waiver
    
    
    22
 
 Section 9.1 Notices
    
    
    22Section 9.2 [Intentionally Omitted]
    
    
    23Section 9.3 [Intentionally Omitted]
    
    
    23Section 9.4 Binding Effect
    
    
    23Section 9.5 Illegality; Severability
    
    
    23Section 9.6 Assignment
    
    
    24Section 9.7 Consent to Jurisdiction; Service of Process; Waiver of Jury Trial
    
    
    24Section 9.8 Further Assurances and Corrective Instruments
    
    
    24Section 9.9 Right to Perform; Advances by Bank
    
    
    25Section 9.10 Amendments, Changes and Modifications
    
    
    25Section 9.11 Execution of Counterparts
    
    
    25Section 9.12 Law Governing Construction of Agreement
    
    
    25Section 9.13 Effective Date
    
    
    25Section 9.14 Conflicting Agreements
    
    
    25Section 9.15 Set-off
    
    
    25
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REIMBURSEMENT AGREEMENT
  RECITALS
         1




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AGREEMENTS
    Definitions
        et seq.
 2




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3




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4




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5




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plus
 6




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7




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8




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ACCOUNTING TERMS
  Rules of Construction
      
 Effective Date of Reimbursement Agreement; Duration of Term and
 9




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and
   Reimbursement and Other Payments
     10




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Section 4.7 Section 14.9
 Section
4.1 Section 5.4
  Section 4.6
    11




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Payments due Upon Expiration of Letters of Credit
 12




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Late Payments
 Increased Costs Due to Change in Law
        13




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Computation
 Payment Procedure
 Business Days
   Obligations Absolute
 14




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Representations, Warranties and Undertakings
 Authority
 Binding Agreements
 Litigation
 No Conflicting Agreements, Laws, etc
 Liens or Security Interests
 15




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Full Disclosure
   Affirmative Covenants of Lessee
 Financial Statements
     Taxes and Claims
 16




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Compliance with Laws
 Books and Records
   Indemnification of Bank
 17




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Indemnification Under Letters of Credit and Letter of Credit Agreements
    Events of Default Defined
   18




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19




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Remedies on Default
   20




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No Remedy Exclusive
 21




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Agreement to Pay Attorneys Fees and Expenses
 Waiver of Event of Default; No Additional Waiver Implied by One Waiver
    Notices Principal Office
 Bank:
    
    Manufacturers and Traders Trust Company25 South Charles Street, 11th FloorBaltimore, Maryland 21201Attention: Letter of Credit Departmentand
 22




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Manufacturers and Traders Trust Company1 Research Court, Suite 400Rockville, Maryland 20850Attention: Arthur L. Perraudwith a copy to:Nancy R. Little, EsquireMcGuireWoods LLPOne James Center901 East Cary StreetRichmond, Virginia 23219Lessee:
    
    Human Genome Sciences, Inc.14200 Shady Grove RoadRockville, Maryland 20850Attention: James H. Davis, ExecutiveVice President, General Counseland Secretary
  [INTENTIONALLY OMITTED]
 [INTENTIONALLY OMITTED]
 Binding Effect
 Illegality; Severability
 Assignment
 23




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Consent to Jurisdiction; Service of Process; Waiver of Jury Trial
      Further Assurances and Corrective Instruments
 24




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Right to Perform; Advances by Bank
 Amendments, Changes and Modifications
 Execution of Counterparts
 Law Governing Construction of Agreement
 Effective Date
 Conflicting Agreements
 Set-off
 25




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WITNESS:

    HUMAN GENOME SCIENCES, INC., as LesseeBy:

/s/
H. Thomas Watkins
    (SEAL)Name:
    H. Thomas WatkinsTitle:

President
and Chief Executive OfficerWITNESS:

    MANUFACTURERS AND TRADERS TRUSTCOMPANY, as BankBy:

/s/
Arthur L. Perraud
    (SEAL)Name:
    Arthur L. PerraudTitle:

Vice
President
 26