3101 WESTERN AVENUE OFFICE LEASE

Exhibit 10.37

3101 WESTERN AVENUE

OFFICE LEASE

THIS LEASE, made the 2 ^nd day of September, 2004, by and between SELIG REAL ESTATE HOLDINGS FOURTEEN, a Washington limited liability company, whose address is 1000 Second Avenue, Suite 1800, Seattle, Washington, 98104-1046, hereinafter referred to as “Lessor,” and DENDREON CORPORATION, whose address is 3005 First Avenue, Seattle, Washington 98121, hereinafter referred to as “Lessee”.

1. DESCRIPTION . Lessor, in consideration of the agreements contained in this lease, does hereby lease to Lessee, upon the terms and conditions hereinafter set forth, that certain space consisting of approximately 21,975 rentable square feet situated on the entire 8 ^th floor level and approximately 1,818 rentable square feet located on the upper parking level of the 3101 Western Avenue Building (collectively, the “Premises”) located at 3101 Western Avenue, City of Seattle, State of Washington 98121, the legal description of which is:

Lots 1,2,3 and South Westerly half of Lot 4, Block 3 of William M. Bell’s 7 ^th addition to the City of Seattle, according to plat thereof, recorded in Volume 2 of plats, page 82, records of King County, Washington, together with North Westerly 66’ of block southerly of Bay Street siding Westerly of Western Avenue and Easterly of Elliott Avenue.

The actual number of rentable square feet of the Premises (the “Rentable Square Feet”) shall be measured by an architect or surveyor mutually acceptable to the parties in accordance with the Building Owners and Managers Association Standard Method for Measuring Area in Office Buildings (ANSI/BOMA Z65.1-1996) and the parties shall executed an addendum to this lease in which such measurement is reflected.

2. TERM . The term of this lease shall be for a period of sixty (60) months, commencing on the later of (a) sixty (60) days after Lessee is given access to the Premises to enable it to commence its tenant improvements, or (b) October 1, 2004 (the later of said dates being herein referred to as the “Commencement Date”), and ending sixty (60) months thereafter.

In the event the Premises are not available for Lessee’s access by November 1, 2004, Lessee shall have the option to cancel this Lease by written notice given to Lessor. No delay in Lessee’s access to the Premises shall extend the date on which this Lease is stated to terminate.

3. RENT . Commencing with the Commencement Date, Lessee covenants and agrees to pay Lessor rent each month in advance on the first day of each calendar month. Except for Lessee’s share of increases in the costs of Operating Services and Real Estate Taxes as stated herein, this lease is on a fully serviced basis and rent shall be computed at the annual base rental rate times the number of Rentable Square Feet as follows:

Rent for any fractional calendar month, at the beginning or end of the term, shall be the pro rated portion of the rent computed on an annual basis.

4. CONSIDERATION . As consideration for the execution of this lease, Lessee shall owe Lessor the sum of $138,792.50, which sum shall be offset against the Tenant Improvement Allowance referred to below, which results in the

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amount of the Tenant Improvement Allowance to be paid to Lessee pursuant to paragraph 31 below to be the difference between the product of $12.50 times the number of Rentable Square Feet minus $138,792.50. Lessee’s offset against the Tenant Improvement Allowance under this Section ($138,792.50) shall be credited against the first and last two (2) months’ rent due under this lease, with any difference between the amount of such offset and said rental to be paid to the party entitled thereto within ten (10) business days after written demand.

5. USES . Lessee agrees that Lessee will use and occupy said Premises for general offices and related purposes and for no other purposes.

6. RULES AND REGULATIONS . Lessee and its employees, agents and contractors shall observe and abide by the rules and regulations Lessor promulgates for the Building. Lessor agrees that such rules and regulations shall be typical of those employed for similar buildings used for general office purposes, shall not interfere with Lessee’s rights under this Lease, shall not discriminate among tenants in the Building, and shall not result in the imposition of additional fees or charges to Lessee. Lessor shall provide Lessee with a written copy of such rules and regulations at least ten (10) days before the same are scheduled to become effective.

7. CARE AND SURRENDER OF PREMISES . Lessee shall take good care of the Premises and shall promptly make all necessary repairs except those required herein to be made by Lessor. At the expiration or sooner termination of this lease, Lessee, without notice, will immediately and peacefully quit and surrender the Premises in good order, condition and repair (damage caused by Lessor or for which Lessor is responsible to repair, reasonable wear and tear, casualty or condemnation excepted). Lessee shall be responsible for removal of all of Lessee’s personal property and signage from the Premises, (excepting fixtures being that which is attached to the Premises, and property of the Lessor), and, to the extent required by law, any communication cabling, telephone equipment installed by Lessee. Lessee shall be responsible for repairing any damage to the Premises caused by such removal.

If Lessee fails to remove and restore the Premises at lease expiration to the extent herein required, then Lessor shall have the right to remove said property and restore the Premises and Lessee shall be responsible for all costs associated therewith. Lessee shall also be responsible for those costs incurred by Lessor for removing debris Lessee may discard in the process of preparing to vacate the Premises, including, but not limited to, the cleaning or replacement of carpets if damage is not caused by reasonable wear, and removal and disposal of Lessee’s personal property remaining in the Premises that Lessee was obligated to remove.

8. ALTERATIONS . Except for the improvements and alterations Lessee makes prior to the Commencement Date or that are funded with the Tenant Improvement Allowance, Lessee shall not make any alterations or improvements in, or additions to said Premises without first obtaining the written consent of Lessor, whose consent shall not be unreasonably withheld, conditioned or delayed. All such alterations, additions and improvements shall be at the sole cost and expense of Lessee and shall become the property of Lessor if they are generic fixtures to the Premises and not in the nature of trade fixtures and shall remain in and be surrendered with the Premises as a part thereof at the termination of this lease, without disturbance, molestation or injury.

9. RESTRICTIONS . Lessee will not use or permit to be used in said Premises anything that will increase the Lessor’s insurance premiums on said Building or any part thereof, nor anything that may be dangerous to life or limb; nor in any manner deface or injure said Building or any part thereof; nor overload any floor or part thereof; nor permit any reasonably objectionable noise or odor to escape or to be emitted from said Premises, or do anything or permit anything to be done upon said Premises in any way that creates a nuisance or that unreasonably disturbs any other tenant or occupant of any part of said Building. Lessee, at Lessee’s expense, will comply with all health, fire and police regulations respecting said Premises, but the foregoing shall not be construed as requiring Lessee to alter, improve or retrofit the Premises to comply with any such laws unless and to the extent the same is required because of Lessee’s particular use.

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The Premises shall not be used for lodging or sleeping, and except where reasonably required to assist handicapped individuals, no animals or birds will be allowed in the Building.

10. WEIGHT RESTRICTIONS . Safes, furniture or bulky articles may be moved in or out of said Premises only at such hours and in such manner as will least inconvenience other tenants, which hours and manner shall be at the discretion of Lessor. No safe or other article of over 2,000 pounds shall be moved into said Premises without the consent of Lessor, whose consent shall not be unreasonably withheld, conditioned or delayed, and Lessor shall have the right to locate the position of any article of weight in said Premises if Lessor so desires.

11. SIGN RESTRICTION . No sign, picture, advertisement or notice shall be displayed, inscribed, painted or affixed to any of the glass or woodwork of the Building without the prior approval of Lessor. Such approval shall not be unreasonably withheld, conditioned or delayed. At such time Lessee leases two (2) or more floors in the 3101 Western Avenue Building, Lessor shall provide Lessee with the right to exclusive building signage on the existing building monument.

12. LOCKS . No additional locks shall be placed upon any doors of the Premises. Keys will be furnished to each door lock. At the termination of the lease, Lessee shall surrender all keys to the Premises whether paid for or not.

13. KEY . Lessor, his janitor, engineer or other agents may retain a pass key to said Premises to enable him to examine the Premises from time to time with reference to any emergency or to the general maintenance of said Premises.

14. TELEPHONE SERVICE . If Lessee desires to install additional telephone or other electrical connections after making the initial tenant improvements that are to be constructed prior to the Commencement Date or would be paid for with the proceeds of the Tenant Improvement Allowance, it shall obtain Lessor’s prior written consent to the manner and location of the introduction of such wires and cables into the Premises.

15. SERVICES . Lessor shall maintain Premises and the public and common areas of Building, such as lobbies, stairs, corridor and restrooms, in a condition consistent to that of Class “A” office buildings in Seattle except to the extend of any damage caused by the act of Lessee.

Lessor shall furnish Premises with electricity for lighting and operation of low power usage office machines, heat, normal office air-conditioning, and elevator services, during the ordinary business hours of the Building. Such hours are Monday through Friday 6:00 a.m. to 6:00 p.m. and Saturday 9:00 a.m. to 1:00 p.m. Air-conditioning units and electricity therefor for special air-conditioning requirements, such as for computer centers, shall be at Lessee’s expense. Lessor shall also provide lighting replacement for Lessor furnished lighting, toilet room supplies, window washing with reasonable frequency, and customary janitor service.

Lessor shall not be liable to Lessee for any loss or damage caused by or resulting from any variation, interruption or any failure of said services due to any cause whatsoever unless the same results from the wrongful acts or omissions of Lessor, its employees, agents or contractors. No temporary interruption or failure of such services incident to the making of repairs, alterations, or improvements, or due to accident or strike or conditions or events not under Lessor’s control shall be deemed as an eviction of Lessee or relieve Lessee from any of Lessee’s obligations hereunder.

In the event of any lack of attention on the part of Lessor and any dissatisfaction with the service of the Building, or any unreasonable annoyance of any kind, Lessee is requested to make complaints at Lessor’s Building office and not to Lessor’s employees or agents seen within the Building.

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Lessee is further requested to remember that Lessor is as anxious as Lessee that a high grade service be maintained, and that the Premises be kept in a state to enable Lessee to transact business with the greatest possible ease and comfort.

16. SOLICITORS . Lessor will make an effort to keep solicitors out of the Building, and Lessee will not oppose Lessor in his attempt to accomplish this end.

17. FLOOR PLAN . The eighth (8 ^th ) floor and upper parking level plans shall be attached hereto and marked Exhibit “A”.

18. ASSIGNMENT . Lessee shall have the right to assign the Lease or sublease the Premises to any entity which is controlled by, under the control of or under the common control with Lessee, or any entity into which Lessee may be merged or consolidated, or which purchases all or substantially all of the assets or stock of Lessee (each an “Affiliate of Lessee”).

Except as provided for in the preceding paragraph, Lessee will not assign this lease, or any interest hereunder without first obtaining the written consent of Lessor, and this lease, or any interest hereunder, shall not be assigned by operation of law. Lessee will not sublet said Premises or any part thereof and will not permit the use of said Premises by others other than Lessee and the agents of Lessee without first obtaining the written consent of Lessor,. Lessor’s consent under this paragraph shall not be unreasonably withheld, conditioned or delayed.

In the event such written consent shall be given, no other or subsequent assignment or subletting shall be made without the previous written consent of Lessor, whose consent shall not be unreasonably withheld, conditioned or delayed.

19. OPERATING SERVICES AND REAL ESTATE TAXES . The annual base rental rate times the Rentable Square Feet in this lease includes Lessee’s proportionate share of Operating Services and Real Estate Taxes for the first twelve months of the lease term, “Base Year Costs”. Only actual increases from these Base Year Costs, if any, will be passed on to Lessee on a proportionate basis as additional rent. Base Year Costs and the actual Costs increases for which Lessee is liable shall include the same items and be calculated in the same manner. Excluding real estate taxes and utilities, expenses shall not increase more than four percent (4%) over the previous twelve (12) months.

DEFINITIONS

Base Year

For computing the Base Year Costs, the base year shall be the calendar year stated herein or if a specific calendar year is not stated herein then the base year shall be the calendar year in which the lease term commences. The base year shall be the calendar year 2004.

Comparison Year

The Comparison Year(s) shall be the calendar year(s) subsequent to the base year.

Operating Services

“Operating Services” include, but are not limited to, the charges incurred by Lessor for: Building operation salaries, benefits, management fee (currently 5%) of gross income for the Building, insurance, electricity, janitorial, supplies, telephone, HVAC, repair and maintenance, window washing, water and sewer, security, landscaping, disposal, elevator, and any other service or supplies reasonably necessary to the use and operation of the premises. Operating Services shall also include the amortization cost of capital costs and of the installation of capital repairs and like kind replacements thereof, which are primarily for the purpose of safety, saving energy or reducing operating costs, or which become required by governmental authority during the term of this lease and do not relate to any previous noncompliance

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(all such costs shall be amortized over the reasonable life of the capital investment item, with the reasonable life and amortization schedule being determined in accordance with generally accepted accounting principles). Notwithstanding anything to the contrary contained herein, Operating Services shall not include any of the following:

(i) real estate taxes

(ii) legal fees, auditing fees, brokerage commissions, advertising costs, or other related expenses incurred by Lessor in an effort to generate rental income;

(iii) repairs, alterations, additions, improvements, or replacements made to rectify or correct any defect in the original design, materials or workmanship of the Building or common areas (but not including repairs, alterations, additions, improvements or replacements made as a result of ordinary wear and tear);

(iv) damage and repairs attributable to fire or other casualty or to condemnation;

(v) damage and repairs necessitated by the negligence or willful misconduct of Lessor, Lessor’s employees, contractors or agents;

(vi) executive salaries to the extent that such services are not in connection with the management, operation, repair or maintenance of the Building;

(vii) Lessor