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                                                                   EXHIBIT 10.14

                           SECOND AMENDMENT TO MASTER
                                LEASE AGREEMENT


          THIS SECOND AMENDMENT to MASTER LEASE AGREEMENT (the "Amendment"),
dated as of January 31, 2000, by and between Dendreon Corporation (the
"Lessee"), a Delaware Corporation, having its principal place of business and
chief executive office at 3005 First Avenue, Seattle, Washington 98121, and
TRANSAMERICA BUSINESS CREDIT CORPORATION (the "Lessor"), a Delaware Corporation,
having its principal office at Riverway II, West Office Tower, 9399 West Higgins
Road, Rosemont, Illinois, 60018.

                                  WITNESSETH:

          WHEREAS, the Lessee and the Lender are parties to a Master Lease
Agreement, dated as of December 11, 1997 as amended and restated on May 28, 1999
(as amended, the "Lease Agreement"; capitalized terms used herein shall have the
meanings assigned to such terms in the Lease Agreement unless otherwise defined
herein); and

          WHEREAS, the parties hereto desire to amend the Lease Agreement in the
manner set forth herein.

          NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the Lessee and Lender hereby agree as follows:

          1.   Amendment to Lease Agreement.  Effective as of the date this
Amendment is fully executed by the Lender and Lessee hereof, and subject to the
satisfaction of the Lessee of conditions as determined by Lender, the Lease
Agreement is hereby amended as follows:

               (a)  The paragraph entitled "Lease" is hereby deleted in its
entirety and the following is inserted in lieu thereof:

                    1.   LEASE.  Subject to and upon all of the terms and
conditions of this Agreement and each Schedule, Lessor hereby agrees to lease to
Lessee and Lessee hereby agrees to lease from Lessor the Equipment for the Term
(as defined in Paragraph 2 below) thereof. The timing and financial scope of
Lessor's obligation to enter into Leases hereunder are limited as set forth in
the Commitment Letters executed by Lessor and Lessee, dated as of October 2,
1997, April 14, 1999 and December 30, 1999 and attached hereto as Exhibit A,
Exhibit B and Exhibit C (collectively the "Commitment Letters").

          2.   Representations and Warranties of the Lessee.  The Lessee
represents and warrants as follows:

               (a). Since May 28, 1999, there has occurred no development, event
or change that has had or could reasonably be expected to have a Material
Adverse Effect.

               (b). No Default or Event of Default has occurred and is
continuing.

                                      1.
<PAGE>

               (c). The representations and warranties of such Lessee contained
in Section 26 of the Lease Agreement are true and correct in all material
respects on the date hereof as though made on and as of the date hereof, except
to the extent that such representation and warranties expressly relate solely to
an earlier date (in which case such representations and warranties were true and
correct on and as of such earlier date).

               (d). This Amendment constitutes the legal, valid and binding
obligation of such Lessee, enforceable against the Lessee in accordance with its
terms, except as enforceability may be limited by bankruptcy, insolvency and
other laws affecting creditors' rights generally and by general principles of
equity.

          3.   Expenses.  The Lessee shall pay for all of the reasonable costs
and expenses incurred by the Lender in connection with the transactions
contemplated by the Amendment, including, without limitation, the reasonable
fees and expenses of counsel to the Lender.

          4.   Miscellaneous.

               (a). Except as expressly amended herein, all of the terms and
provisions of the Lease Agreement and the other Lease Documents are ratified and
confirmed in all respects and shall remain in full force and effect.

               (b). Upon the effectiveness of the Amendment, all references in
the Lease Documents to the Lease Agreement shall mean the Lease Agreement as
amended by this Amendment and all references to the Lease Agreement to the "this
Agreement", "hereof", "herein", or similar terms, shall mean and refer to the
Lease Agreement as amended by this Amendment.

               (c). The execution, delivery and effectiveness of this Amendment
shall not, except as expressly provided herein, operate as an amendment to or
waiver of any right, power or remedy of the Lender under any of the Lease
Documents, or constitute an amendment or waiver of any provision of any of the
Lease Documents.

               (d). This Amendment may be executed by the parties hereto
individually or in combination, in one or more counterparts, each of which shall
be an original and all of which shall constitute one and the same agreement.
This Amendment may be executed and delivered by telecopier with the same force
and effect as if the same were a fully executed and delivered original manual
counterpart.

               (e)  This Amendment shall constitute a Lease Document.

          5.   Governing Law.  THE VALIDITY, INTERPRETATION AND ENFORCEMENT OF
THIS AMENDMENT SHALL BE GOVERNED BY THE LAWS OF THE STATE OF ILLINOIS WITHOUT
GIVING EFFECT TO THE CONFLICTS OF LAW PRINCIPLES THEREOF.

                                      2.
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                                                   Exhibit A to Second Amendment

See Exhibit A to Amended and Restated Master Lease Agreement

                                      3.
<PAGE>

                                                   Exhibit B to Second Amendment

See Exhibit B to Amended and Restated Master Lease Agreement
<PAGE>

                                                                       Exhibit C

                   [TRANSAMERICA BUSINESS CREDIT LETTERHEAD]


December 30, 1999

Martin Simonetti
Chief Financial Officer
Dendreon Corporation
3005 First Avenue
Seattle, WA  98121

Dear Martin:

Transamerica Business Credit Corporation - Technology Finance Division
("Lessor") is pleased to offer this commitment (this "Commitment") to lease the
equipment described below to Dendreon Corporation ("Lessee").  Except with
respect to the transactions described in commitment letters dated as of October
2, 1997, April 14, 1999 and July 9, 1999 (collectively referred to as the "Prior
Commitments"), this Commitment supercedes all prior correspondence, proposals,
and oral or other communications relating to leasing arrangements between Lessor
and Lessee.

The outline of this offer is as follows:

Lessor:                    Transamerica Business Credit Corporation -Technology
                           Finance Division and/or its affiliates, successors or
                           assigns.

Lessee:                    Dendreon Corporation

Equipment Cost:            Not to exceed $1,500,000 in the aggregate (in
                           addition to the Prior Commitments). The availability
                           under the Prior Commitments must be completely drawn-
                           down prior to any funding under this Commitment.

Equipment:                 Various laboratory, office equipment and computer
                           equipment and related soft costs (the "Equipment").
                           All Equipment subject to Lessor approval prior to
                           funding.

Location of Equipment:     Seattle, WA

Availability and           $1,000,000 will be available immediately upon the
Draw Down Expiration:      closing of this transaction with the remaining
                           $500,000 available upon the closing of an additional
                           equity financing of not less than $8,000,000 or a
                           corporate agreement which provides no less than
                           $8,000,000 in "up-front" cash proceeds. No Leases
                           will be
<PAGE>

                           funded after September 30, 2000.

Lease Term:                Each Lease Term will commence upon delivery of the
                           equipment or upon each delivery of items of equipment
                           having an aggregate cost of not less than $50,000,
                           and will continue through 48 months from the first
                           day of the month next following or coincident with
                           commencement of that Lease Term.

Payment Terms:             Month Rent equal to 2.52% of Equipment Cost will be
                           payable monthly in advance. The first month's rent
                           will be payable upon signing the lease.

Adjustment to              The Lessor will increase or decrease the Monthly
Payment Terms              Lease Payment as of the date of each Lease Term
                           Commencement proportionally to the change in the
                           weekly average of the interest rates of the four-year
                           U.S. Treasury Securities from the week ending
                           November 12, 1999 (5.87%) to the week preceding the
                           date of each Lease Term Commencement, as published in
                           the Wall Street Journal. As of the date of each Lease
                           Term Commencement, the Monthly Lease Payments will be
                           fixed for the term. A schedule of the actual Monthly
                           Lease Payments will be provided by the Lessor
                           following each Lease Term Commencement.

Purchase Options:          The Lessee will have the option to purchase all (but
                           not less than all) the Equipment at the expiration of
                           the term of the lease for ten percent (10%) of
                           Equipment Cost, plus applicable sales and other
                           taxes.

Automatic Renewal:         In the event the Lessee does not exercise the
                           Purchase Option described above, the lease will
                           automatically renew for a term of one year with
                           Monthly Rentals equal to 1.00% of Equipment Cost
                           payable monthly in advance. At the expiration of the
                           renewal period, the Lessee will have the option to
                           purchase all (but not less than all) the Equipment
                           for $1.00.

Interim Rent:              Interim Rent will accrue from the date each Lease
                           Term commences until the next following first day of
                           a month (unless the Lease Term commences on the first
                           day of a month). Interim Rent will be calculated at
                           the daily equivalent of the currently adjusted
                           Monthly Rent.

Net Lease:                 The Leases will be net leases under which the Lessee
                           will be responsible for maintenance, insurance, taxes
                           and all other costs and expenses.

Taxes:                     Sales or use taxes will be added to the Equipment
                           Cost or

                                      2.
<PAGE>

                           collected on the gross rentals, as
                           appropriate.

Insurance:                 Prior to any delivery of equipment, the Lessee will
                           furnish confirmation of insurance acceptable to the
                           Lessor covering the Equipment including primary, all
                           risk, physical damage, property damage and bodily
                           injury with appropriate loss payee and additional
                           insured endorsements in favor of the Lessor.

Conditions Precedent       1.  No material adverse change in the financial
to Each Lease Term             condition, operation or prospects of the Lessee
Commencement:                  prior to funding. The Lessor reserves the right
                               to rescind any unused portion of its commitment
                               in the event of a material adverse change in the
                               financial condition, operation or prospects of
                               the Lessee.

                           2.  Completion of the documentation and final terms
                               of the proposed financing satisfactory to Lessor
                               and Lessor's counsel.

                           3.  Results of all due diligence, including lien,
                               judgment and tax searches and other matters
                               Lessor may reasonably request shall be
                               satisfactory to Lessor and Lessor's counsel.

                           4.  Receipt by Lessor of duly executed Lease
                               documentation in form and substance satisfactory
                               to Lessor and its counsel.

                           5.  Lessor shall receive title and a valid and
                               perfected first priority lien and security
                               interest in all Collateral acquired through the
                               use of this Commitment and Lessor shall have
                               received satisfactory evidence that there are no
                               liens on any Collateral except as expressly
                               permitted herein.

                           6.  Satisfactory updated reference from Vulcan
                               Ventures.

Additional Covenants:      There will be no actual or threatened conflict with,
                           or violation of, any regulatory statute standard or
                           rule relating to the Lessee, its present or future
                           operations, or the Collateral.

                           Lessee will be required to provide quarterly
                           financial information. All information supplied by
                           the Lessee will be correct and will not omit any
                           statement necessary to make the information supplied
                           not be misleading. There will be no material breach
                           of the representations and warranties of the Lessee
                           in the Loan.

Expenses:                  All costs and expenses incurred by the Lessor in
                           connection with the underwriting and closing of the
                           Leases will be paid by the Lessee whether or not any
                           Leases are consummated and funds are advanced by the
                           Lessor.

Law:                       This letter and the proposed Lease are intended to be
                           governed by and construed in accordance with Illinois
                           law without regard to its conflict of law provisions.

                                      3.
<PAGE>

Indemnity:                 Lessee agrees to indemnify and to hold harmless
                           Lessor, and its officers, directors and employees
                           against all claims, damages, liabilities and expenses
                           which may be incurred by or asserted against any such
                           person in connection with or arising out of this
                           letter and the transactions contemplated hereby,
                           other than claims, damages, liability, and expense
                           resulting from such person's gross negligence or
                           willful misconduct.

Confidentiality:           This letter is delivered to you with the
                           understanding that neither it nor its substance shall
                           be disclosed publicly or privately to any third
                           person except those who are in confidential
                           relationship to you (such as your legal counsel and
                           accountants), or where the same is required by law
                           and then only on the basis that it not be further
                           disclosed, which conditions Lessee and its agents
                           agree to be bound by upon acceptance of this letter.

                           Without limiting the generality of the foregoing,
                           none of such persons shall use or refer to Lessor or
                           to any affiliate name in any disclosures made in
                           connection with any of the transactions without
                           Lessor's prior written consent.

                           Upon completion of the initial takedown by Lessor and
                           Lessee, the Lessee will no longer be required to
                           obtain Lessor's prior written consent to disclose the
                           transaction contemplated hereby. In addition, the
                           Lessee agrees to provide camera ready artwork of
                           typestyles and logos of the Lessee for use in
                           promotional material by the Lessor and Lessee, upon
                           request by of Lessor, agrees to issue a press release
                           relating to the proposed financing.

Conditions of              This Commitment Letter is intended to be a summary of
Acceptance:                the most important elements of the agreement to enter
                           into a leasing transaction with Lessee, and it is
                           subject to all requirements and conditions contained
                           in Lease documentation proposed by Lessor or its
                           counsel in the course of closing the Lease described
                           herein. Not every provision that imposes duties,
                           obligations, burdens, or limitations on Lessee is
                           contained herein, but shall be contained in the final
                           Lease documentation satisfactory to Lessor and its
                           counsel.

                           EACH OF THE PARTIES HERETO IRREVOCABLY AND
                           UNCONDITIONALLY WAIVES ALL RIGHT TO TRAIL BY JURY IN
                           ANY SUIT, ACTION, PROCEEDING OR COUNTERCLAIM ARISING
                           OUT OF OR RELATED TO THIS LETTER OR THE TRANSACITON
                           DESCRIBED IN

                                      4.
<PAGE>

                           THIS LETTER.

Application Fee:           The $15,000 Application Fee previously paid by the
                           Borrower will be first applied to the reasonable
                           costs and expenses of the Lender in connection with
                           the transaction, and any remainder shall be applied
                           pro rata (based on the amount of each funding to the
                           total amount of this Commitment) to the second
                           month's payment due under the Loan.

Commitment Expiration:     This Commitment shall expire on January 7, 2000
                           unless prior thereto either extended in writing by
                           the Lender or accepted as provided below by the
                           Borrower.


Should you have any questions, please call me.  If you wish to accept this
Commitment, please so indicate by signing and returning the enclosed duplicate
copy of this letter to me by January 7, 2000.

                                    Yours truly,

                                    TRANSAMERICA BUSINESS CREDIT CORP -
                                    TECHNOLOGY FINANCE DIVISION

                                    By  /s/ Gerald A. Michaud
                                      --------------------------------
                                      Gerald A. Michaud
                                      Senior Vice President - Marketing

Accepted this  4/th/ day of January, 2000.

DENDREON CORPORATION

By  /s/ Martin A. Simonetti
  -------------------------------
  Chief Financial Officer

                                      5.