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                                                                   EXHIBIT 10.18

                                 AMENDMENT NO. 1
                                       TO
                       NASTECH PHARMACEUTICAL COMPANY INC.
            AMENDED AND RESTATED 2000 NONQUALIFIED STOCK OPTION PLAN

     Pursuant to the resolutions adopted by the Board of Directors of Nastech
Pharmaceutical Company Inc. (the "Company") on January 23, 2006, the following
amendments to the Amended and Restated Nastech Pharmaceutical Company Inc. 2000
Nonqualified Stock Option Plan are hereby adopted effective as of January 23,
2006:

1.   Paragraph 6(c) is hereby deleted in its entirety and replaced with the
     following:

          "(c) Payment. Stock options may be exercised in whole or in part by
     payment of the exercise price of the shares to be acquired in accordance
     with the provisions of the Grant Agreement, and/or such rules and
     regulations as the Committee may have prescribed, and/or such
     determinations, orders, or decisions as the Committee may have made.
     Payment may be made in cash (or cash equivalents acceptable to the
     Committee) or, with the prior approval of the Corporation's compliance
     officer, which officer shall have sole discretion whether or not to give,
     in shares of Common Stock or a combination of cash and shares of Common
     Stock, or by such other means as the Committee may prescribe. The Fair
     Market Value of shares of Common Stock delivered on exercise of stock
     options shall be determined as of the date of exercise. Shares of Common
     Stock delivered in payment of the exercise price may be previously owned
     shares or, with the prior approval of the Corporation's compliance officer,
     which officer shall have sole discretion whether or not to give, the shares
     that are being acquired upon exercise of the stock option; provided,
     however, that any person who is a reporting person for purposes of Section
     16 of the Exchange Act may only deliver shares that are being acquired upon
     exercise of the stock option in this manner if at least six months has
     elapsed from the date on which the option was granted to such person. Any
     fractional share will be paid in cash. The Corporation may make or
     guarantee loans to grantees to assist grantees in exercising stock options
     and satisfying any related withholding tax obligations.

          If the Common Stock is registered under Section 12(b) or 12(g) of the
     Exchange Act, the Committee, subject to such limitations as it may
     determine, may authorize payment of the exercise price, in whole or in
     part, by delivery of a properly executed exercise notice, together with
     irrevocable instructions, to: (i) a brokerage firm to deliver promptly to
     the Corporation the aggregate amount of sale or loan proceeds to pay the
     exercise price and any withholding tax obligations that may arise in
     connection with the exercise, and (ii) the Corporation to deliver the
     certificates for such purchased shares directly to such brokerage firm."

2.   Paragraph 7 is hereby deleted in its entirety and replaced with the
     following:

          "7. Withholding of Taxes. The Corporation may require, as a condition
     to the exercise of an Option granted under the Plan (hereinafter
     collectively referred to as a "taxable event"), that the grantee pay to the
     Corporation, in cash or, with the prior approval of the Corporation's
     compliance officer, which officer shall have sole discretion whether or not
     to give, in shares of Common Stock, including shares acquired upon exercise
     of an Option, valued at Fair Market Value on the date as of which the
     withholding tax liability is determined, any federal, state or local taxes
     of any kind required by law to be withheld with respect to any taxable
     event under the Plan. The Corporation, to the extent permitted or required
     by law, shall have the right to deduct

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     from any payment of any kind (including salary or bonus) otherwise due to a
     grantee any federal, state or local taxes of any kind required by law to be
     withheld with respect to any taxable event under the Plan, or to retain or
     sell without notice a sufficient number of the shares to be issued to such
     grantee to cover any such taxes. Any person that is subject to Section 16
     of the Exchange Act may not surrender shares to satisfy tax withholding
     obligations if such surrender would not be in compliance with applicable
     provisions of Rule 16b-3(e) of the Exchange Act."