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                                                                   Exhibit 10.7

                            FIRST AMENDMENT TO LEASE

     This FIRST AMENDMENT TO LEASE is made as of this 17th day of July, 2006, by
and between DITTY PROPERTIES LIMITED PARTNERSHIP, a Washington limited
partnership ("Landlord"), and NASTECH PHARMACEUTICAL COMPANY, INC., a Washington
corporation ("Tenant").

                                    RECITALS

     A. Landlord and Tenant are parties to that certain Lease dated March 1,
2006, (the "Lease") pursuant to which Tenant leased certain space from Landlord
in the building located at 3830 Monte Villa Parkway, Bothell, Washington (the
"Original Premises").

     B. Pursuant to Section 2.3 of the Lease, Tenant has a right of first
refusal to lease additional space in the Building and has exercised such right
with respect to the balance of the Building.

     C. The parties now wish to amend the Lease to document the addition of RFR
space to the Premises, subject to and in accordance with the following terms and
conditions.

                                   AGREEMENTS

     NOW, THEREFORE, in consideration of the mutual covenants and agreements
herein contained, and other good and valuable consideration, the receipt and
sufficiency of which are hereby mutually acknowledged, the parties hereto agree
as follows:

     1. TERMS. All terms used herein and not defined herein shall have the
meanings ascribed to them in the Lease.

     2. ADDITIONAL PREMISES. In addition to the Original Premises, effective as
of the date on which Landlord delivers possession of the space to Tenant in the
condition required under Section 2.3 of the Lease (the "Effective Date"), Tenant
shall lease from Landlord the balance of the rentable area in the Building (the
"Additional Premises") and thereafter the term "Premises" shall include the
Additional Premises. The Effective Date will be July 16, 2006. Landlord shall
not be liable for any delay and this Amendment shall not be void or voidable if
the Effective Date is delayed for any reason unless, prior to August 1, 2006,
same is due to Force Majeure, Landlord's negligence or misconduct, or failure of
Landlord to deliver the Additional Premises free of chemical hazards of which it
has actual knowledge. Landlord shall not be required to make any alterations to
the Additional Premises nor to contribute any funds toward alterations of the
Additional Premises except as expressly provided for herein or in the Lease.
Base Rent on the Additional Premises shall commence on the Effective Date at the
per square foot rate applicable to the Original Premises during months 6-12 as
shown in Section 1.C of the Lease. From and after the Effective Date Tenant
shall be a single tenant in the building and Tenant's Share shall be one hundred
percent (100%). From and after the date hereof, Tenant shall have no further
rights to lease space under Section 2.3 of the Lease.

     3. SQUARE FOOTAGE. Both Landlord and Tenant have engaged independent
architects who have confirmed that the Gross Building Area of the entire
Premises is 63,200 square feet and that, as a single tenant, Nastech shall be
entitled to use the entire 63,200 square feet. Landlord and Tenant agree that,
for purposes of calculating rent under this

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agreement, one-half of the Premises, or 31,600 square feet, shall be considered
lab space and one-half of the Premises, or 31,600 square feet, shall be
considered office space.

     4. ALLOWANCE. The parties agree that the Commencement Date under the Lease
was March 1, 2006, and the prorated allowance payable by Landlord with respect
to the Additional Premises shall be calculated using that date. For example if
the Effective Date is July 16, 2006, then the prorated Allowance shall be
Fourteen and 44/100 Dollars ($14.44) per RSF which is Fifteen Dollars multiplied
by 115.5/120. On the Additional Premises of 35,878 rentable square feet, this
Allowance is $518,078.

     5. SECURITY DEPOSIT. To reflect the addition of the Additional Premises,
Tenant shall increase its Security Deposit by $656,577 (which is the $500,000
existing letter of credit divided by 27,322 square feet (i.e., $18.30) times the
Additional Premises of 35,878 square feet) to a total of $1,156,577.

     6. BROKER'S COMMISSION. Tenant represents and warrants to Landlord that it
has had no dealing with any broker or agent in connection with this Amendment.
Landlord shall not be required to pay any broker's fee in connection with the
lease of the Additional Premises and Tenant shall indemnify, defend and hold
Landlord harmless from and against any and all liabilities for any commissions
or other compensation or charges claimed by any broker or agent based on
dealings with Tenant in connection with the lease of the Additional Premises.

     7. DEFINED TERMS; CONFLICT. Capitalized terms used herein and not otherwise
defined shall have the meanings given in the Lease. If there is any conflict
between the terms, conditions and provisions of this Amendment and the terms and
conditions of the Lease, the terms, conditions and provisions of this Amendment
shall prevail.

     8. NO FURTHER AMENDMENT. Except as expressly modified by this Amendment,
all terms, covenants and provisions of the Lease shall remain unmodified and in
full force and effect and are hereby expressly ratified and confirmed.

     9. CONFIRMATION. Tenant represents and warrants to Landlord that, as of the
date hereof and to the Tenant's actual knowledge: (a) no defenses or offsets
exist to the enforcement of the Lease by Landlord and there are no unresolved or
pending disputes or claims between Landlord and Tenant with respect to the Lease
or the Premises; (b) neither Tenant nor Landlord is in default in the
performance of the Lease; and (c) neither Tenant nor Landlord has committed any
breach of the Lease, nor has any event occurred which, with the passage of time
or the giving of notice or both, would constitute a default or a breach by
Tenant or Landlord under the Lease.

     10. ENTIRE AGREEMENT. This Amendment sets forth the entire agreement of the
parties as to the subject matter hereof and supersedes all prior discussions and
understandings between them. This Amendment may not be amended or rescinded in
any manner except by an instrument in writing signed by a duly authorized
officer or representative of each party hereto. This Amendment shall control
over any conflicting terms of the Lease. The parties confirm and acknowledge
that there are no other promises, covenants, understandings, agreements,
representations or warranties with respect to the subject matter of this
Amendment except as expressly set forth herein. Each of the schedules or
exhibits referred to herein (if any), is incorporated herein as if fully set
forth in this Amendment. If any of the provisions of this Amendment be found to
be invalid, illegal or unenforceable by any court of competent jurisdiction,
such provision shall be stricken and the remainder of this Amendment shall


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nonetheless remain in full force and effect unless striking such provision shall
materially alter the intention of the parties. No waiver of any right under this
Amendment shall be effective unless contained in a writing signed by a duly
authorized officer or representative of the party sought to be charged with the
waiver and no waiver of any right arising from any breach or failure to perform
shall be deemed to be a waiver of any future right or of any other right arising
under this Amendment.

     11. REPRESENTATION. Tenant acknowledges that it has been represented, or
has had sufficient opportunity to obtain representation of counsel with respect
to this Amendment. Tenant represents to Landlord that Tenant has read and
understood the terms hereof and the consequences of executing this Amendment and
that, except as expressly set forth herein, no representations have been made to
Tenant to induce the execution of this Amendment. Tenant further waives any
right it may have to require the provisions of this Amendment to be construed
against the party who drafted it.

     12. AUTHORITY. Each person signing this Amendment on behalf of the
respective parties represents and warrants that he or she is authorized to
execute and deliver this Amendment, and that this Amendment will thereby become
binding upon Landlord and Tenant, respectively.

     13. COUNTERPARTS. This Amendment may be executed in counterparts, each of
which will be deemed to be an original, but all of which together will
constitute one and the same document.

     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the day and year first above written.

                                        LANDLORD:

                                        DITTY PROPERTIES LIMITED PARTNERSHIP


                                        By: /s/ R. Kirk Mathewson
                                            ------------------------------------
                                            Its President and General Partner


                                        TENANT:

                                        NASTECH PHARMACEUTICAL COMPANY, INC.


                                        By: /s/ Phil Ranker
                                            ------------------------------------
                                            Its CFO

STATE OF WASHINGTON   )
                      ) ss.
COUNTY OF KING        )


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     On this 17thday of July, 2006, before me, the undersigned, a Notary Public
in and for the State of Washington, personally appeared R. Kirk Mathewsn, to me
known to be the President and General Partner of DITTY PROPERTIES LIMITED
PARTNERSHIP, the corporation that executed the foregoing instrument, and
acknowledged the said instrument to be the free and voluntary act and deed of
said corporation, for the uses and purposes therein mentioned, and on oath
stated that he/she was authorized to execute the said instrument on behalf of
said corporation.

     WITNESS MY HAND AND OFFICIAL SEAL hereto affixed the day and year first
above written.


                                        /s/ S. C. Mathewson
                                        ----------------------------------------
                                        Name: S.C. Mathewson
                                        NOTARY PUBLIC and for the State of
                                        Washington, residing at King Co.
                                        My commission expires 11-20-07
STATE OF WASHINGTON   )
                      ) ss.
COUNTY OFSnohomish    )

     On this 17th day of July, 2006, before me, the undersigned, a Notary Public
in and for the State of Washington, personally appeared Philip Ranker, to me
known to be the Chief Financial Officer of NASTECH PHARMACEUTICAL COMPANY, INC.,
the corporation that executed the foregoing instrument, and acknowledged the
said instrument to be the free and voluntary act and deed of said corporation,
for the uses and purposes therein mentioned, and on oath stated that he/she was
authorized to execute the said instrument on behalf of said corporation.

     WITNESS MY HAND AND OFFICIAL SEAL hereto affixed the day and year first
above written.


                                        /s/ Leslie M. Kodish
                                        ----------------------------------------
                                        Name: Leslie M. Kodish
                                        NOTARY PUBLIC and for the State of
                                        Washington, residing at Renton, WA
                                        My commission expires 5-29-07


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