Document:

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                                                                    Exhibit 10.1

                             FIRST LEASE AMENDMENT

                                    Between

                         BENAROYA CAPITAL COMPANY, LLC

                                      And

                         TARGETED GENETICS CORPORATION

This First Lease Amendment is attached to and made part of that certain Lease
dated October 7, 1996 (the "Lease"), by and between Benaroya Capital, LLC., a
Washington limited liability company, hereinafter called Lessor ("Lessor"), and
Targeted Genetics Corporation, a Washington corporation, hereinafter called the
Lessee ("Lessee"), covering Suite 100 (4,720 RSF) located in the property
commonly known as Metropolitan Park West and located at 1100 Olive Way, Seattle,
Washington, (the "Premises"). The Premises are more particularly described in
the Lease. The terms used herein shall have the same definitions as set forth in
the Lease.

Whereas, pursuant to Section 6, Exhibit G, Riders to Lease, Lessor has exercised
its option to recapture the 105 rentable square feet of Additional Space for
Lessee as illustrated on Exhibit A, Floor Plan of premises of the Lease.

Now, therefore, in consideration of the mutual covenants and promises contained
in this First Lease Amendment and the Lease, Lessor and Lessee agree as follows:

1.   Section 1, Premises.  Section 1, Premises, of the Lease is hereby amended
     to increase the Premises' rentable square feet to 4,825, effective January
     1, 1997.

2.   Section 3, Monthly Minimum Rent.  Section 3, Monthly Minimum Rent is
     amended as follows:

                     Period                     Monthly Minimum Rent
                     ------                     --------------------
               1/10/97 - 12/31/99                    $7,568.00
               1/01/00 - 12/31/01                    $7,869.00
               1/01/02 - 03/31/04                    $8,974.00

3.   Section 10, Additional Rent and Monthly Operating Expense Adjustments.
     Section 10, Additional Rent and Monthly Operating Expense Adjustments, of
     the Lease is hereby amended to increase Lessee's pro-rata share of
     Operating Expenses to 1.528%.

4.   Except as otherwise modified by the terms of this First Lease Amendment,
     all other terms and conditions of the Lease remain unchanged and in full
     force and effect.
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DATED this 12th day of May, 1997.

LESSOR:                                LESSEE:

BENAROYA CAPITAL COMPANY, LLC          TARGETED GENETICS CORPORATION

/s/ Larry R. Benaroya                  /s/ James A. Johnson
----------------------                 -----------------------
By:  Larry R. Benaroya                 By:  James A. Johnson
Its: Manager                           Its: CFO
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STATE OF WASHINGTON ]
                    ] ss.
COUNTY OF KING      ]

     I certify that I know or have satisfactory evidence that Larry R. Benaroya
is the person who appeared before me, a Notary Public in and for the State of
Washington duly commissioned and sworn, and acknowledged that he is the Manager
of Benaroya Capital Company, LLC, a Washington limited liability company, who
executed the within and foregoing instrument, and acknowledged the instrument to
be the free and voluntary act and deed of said company for the uses and purposes
therein mentioned, and on oath stated that affiant is authorized to execute said
instrument on behalf of said company.

IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal the
day and year first above written.

               /s/ Patricia Venable
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               Notary Public in and for the State of    Washington
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               Residing at                              Issaquah
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               Commission expires                       11-4-1999
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               Print Name                               Patricia Venable
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STATE OF WASHINGTON ]
                    ] ss.
COUNTY OF KING      ]

     I certify that I know or have satisfactory evidence that James A. Johnson
is the person who appeared before me, a Notary Public in and for the State of
Washington duly commissioned and sworn, and acknowledged that he is the CFO of
Targeted Genetics Corporation, a Washington limited liability company, who
executed the within and foregoing instrument, and acknowledged the instrument to
be the free and voluntary act and deed of said company for the uses and purposes
therein mentioned, and on oath stated that affiant is authorized to execute said
instrument on behalf of said company.

IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal the
day and year first above written.

               /s/ Jon M. Case
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               Notary Public in and for the State of    Washington
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               Residing at                              Seattle, Washington
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               Commission expires                       10/29/97
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               Print Name                               Jon M. Case
               -----------------------------------------------------------------<PAGE>

                                                                    Exhibit 10.2

                            SECOND LEASE AMENDMENT
                            ----------------------

                                    Between

                         BENAROYA CAPITAL COMPANY, LLC

                                      And

                         TARGETED GENETICS CORPORATION

This Second Lease Amendment dated February 25, 2000 is attached to and made part
of that certain Lease dated October 7, 1996, as amended in the First Lease
Amendment dated May 12, 1997 (the "Lease"), by and between Benaroya Capital
Company, LLC, a Washington limited liability company, hereinafter called Lessor
("Lessor"), and Targeted Genetics Corporation, a Washington corporation,
hereinafter called the Lessee ("Lessee"), covering Suite 100 located in the
property commonly known as Metropolitan Park West at 1100 Olive Way, Seattle,
Washington, 98101 (the "Premises"). The Premises are more particularly described
in the Lease.

The terms used herein shall have the same definitions as set forth in the Lease.

In consideration of the mutual covenants and promises contained in this Second
Lease Amendment, the First Lease Amendment and the Lease, Lessor and Lessee
agree as follows:

1.   Section 3, Monthly Minimum Rent.  Section 3, Monthly Minimum Rent is
     amended as follows:

                     Period                     Monthly Minimum Rent
                     ------                     --------------------
               1/10/97 - 12/31/99                  $ 7,568.00
               1/01/00 - 2/29/00                   $ 7,869.00
               3/01/00 - 12/31/01                  $12,977.00
               1/01/02 - 03/31/04                  $14,082.00

By execution below, Lessee and Lessor acknowledge that the lessor will have no
further obligation to finance any of the Lessee's work related to the Premises.

LESSOR:                                LESSEE:

BENAROYA CAPITAL COMPANY, LLC          TARGETED GENETICS CORPORATION

/s/ Larry R. Benaroya                  /s/ James A. Johnson
----------------------                 --------------------------
By:  Larry R. Benaroya                 By:  James A. Johnson
Its: Manager                           Its: Senior Vice President
<PAGE>

STATE OF WASHINGTON ]
                    ] ss.
COUNTY OF KING      ]

     I certify that I know or have satisfactory evidence that Larry R. Benaroya
is the person who appeared before me, a Notary Public in and for the State of
Washington duly commissioned and sworn, and acknowledged that he is the Manager
of BENAROYA CAPITAL COMPANY, LLC, a Washington limited liability company, who
executed the within and foregoing instrument, and acknowledged the instrument to
be the free and voluntary act and deed of said company for the uses and purposes
therein mentioned, and on oath stated that affiant is authorized to execute said
instrument on behalf of said company.

IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal the
day and year first above written.

               /s/ Rebecca A. Bethel
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               Notary Public in and for the State of    Washington
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               Residing at                              Seattle
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               Commission expires                       11/9/02
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               Print Name                               Rebecca A. Bethel
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STATE OF WASHINGTON ]
                    ] ss.
COUNTY OF KING      ]

     I certify that I know or have satisfactory evidence that James A. Johnson,
of TARGETED GENETICS CORPORATION, is the person who appeared before me, a Notary
Public in and for the State of Washington duly commissioned and sworn, and
acknowledged that he/she is the individual who has executed the within and
foregoing instrument, and acknowledged the instrument to be the free and
voluntary act and deed of said company for the uses and purposes therein
mentioned.

IN WITNESS WHEREOF I have hereunto set my hand and affixed my official seal the
day and year first above written.

               /s/ N. Amy Tsuruta Jones
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               Notary Public in and for the State of    Washington
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               Residing at                              Maple Valley, WA
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               Commission expires                       9/21/2003
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               Print Name                               N. Amy Tsuruta Jones
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