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                                                                   EXHIBIT 10.20

WELLS FARGO                                        REVOLVING LINE OF CREDIT NOTE
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$9,000,000.00                                               BELLEVUE, WASHINGTON
                                                               DECEMBER 19, 2003

FOR VALUE RECEIVED, the undersigned NASTECH PHARMACEUTICAL COMPANY INC.
("Borrower") promises to pay to the order of WELLS FARGO BANK, NATIONAL
ASSOCIATION ("Bank") at its office at BELLEVUE RCBO, 205 108TH AVENUE, NE, SUITE
600 , BELLEVUE, WA 98004, or at such other place as the holder hereof may
designate, in lawful money of the United States of America and in immediately
available funds, the principal sum of $9,000,000.00, or so much thereof as may
be advanced and be outstanding, with interest thereon, to be computed on each
advance from the date of its disbursement as set forth herein.

1.       DEFINITIONS:

         As used herein, the following terms shall have the meanings set forth
after each, and any other term defined in this Note shall have the meaning set
forth at the place defined:

1.1      "Business Day" means any day except a Saturday, Sunday or any other day
on which commercial banks in Washington are authorized or required by law to
close.

1.2      "Fixed Rate Term" means a period commencing on a Business Day and
continuing for 1, 2 OR 3 MONTHS, as designated by Borrower, during which all or
a portion of the outstanding principal balance of this Note bears interest
determined in relation to LIBOR; provided however, that no Fixed Rate Term may
be selected for a principal amount less than $500,000.00; and provided further,
that no Fixed Rate Term shall extend beyond the scheduled maturity date hereof.
If any Fixed Rate Term would end on a day which is not a Business Day, then such
Fixed Rate Term shall be extended to the next succeeding Business Day.

1.3      "LIBOR" means the rate per annum (rounded upward, if necessary, to the
nearest whole 1/8 of 1%) determined by dividing Base LIBOR by a percentage equal
to 100% less any LIBOR Reserve Percentage.

         (a)      "Base LIBOR" means the rate per annum for United States dollar
         deposits quoted by Bank as the Inter-Bank Market Offered Rate, with the
         understanding that such rate is quoted by Bank for the purpose of
         calculating effective rates of interest for loans making reference
         thereto, on the first day of a Fixed Rate Term for delivery of funds on
         said date for a period of time approximately equal to the number of
         days in such Fixed Rate Term and in an amount approximately equal to
         the principal amount to which such Fixed Rate Term applies. Borrower
         understands and agrees that Bank may base its quotation of the
         Inter-Bank Market Offered Rate upon such offers or other market
         indicators of the Inter-Bank Market as Bank in its discretion deems
         appropriate including, but not limited to, the rate offered for U.S.
         dollar deposits on the London Inter-Bank Market.

         (b)      "LIBOR Reserve Percentage" means the reserve percentage
         prescribed by the Board of Governors of the Federal Reserve System (or
         any successor) for "Eurocurrency Liabilities" (as defined in Regulation
         D of the Federal Reserve Board, as amended), adjusted by Bank for
         expected changes in such reserve percentage during the applicable Fixed
         Rate Term.

1.4      "Prime Rate" means at any time the rate of interest most recently
announced within Bank at its principal office as its Prime Rate, with the
understanding that the Prime Rate is one of Bank's base rates and serves as the
basis upon which effective rates of interest are calculated for those loans
making reference thereto, and is evidenced by the recording thereof after its
announcement in such internal publication or publications as Bank may designate.

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2.       INTEREST:

2.1      Interest. The outstanding principal balance of this Note shall bear
interest (computed on the basis of a 360-day year, actual days elapsed) either
(a) at a fluctuating rate per annum 1.50000% below the Prime Rate in effect from
time to time, or (b) at a fixed rate per annum determined by Bank to be .75000%
above LIBOR in effect on the first day of the applicable Fixed Rate Term. When
interest is determined in relation to the Prime Rate, each change in the rate of
interest hereunder shall become effective on the date each Prime Rate change is
announced within Bank. With respect to each LIBOR selection option selected
hereunder, Bank is hereby authorized to note the date, principal amount,
interest rate and Fixed Rate Term applicable thereto and any payments made
thereon on Bank's books and records (either manually or by electronic entry)
and/or on any schedule attached to this Note, which notations shall be prima
facie evidence of the accuracy of the information noted.

2.2      Selection of Interest Rate Options. At any time any portion of this
Note bears interest determined in relation to LIBOR, it may be continued by
Borrower at the end of the Fixed Rate Term applicable thereto so that all or a
portion thereof bears interest determined in relation to the Prime Rate or to
LIBOR for a new Fixed Rate Term designated by Borrower. At any time any portion
of this Note bears interest determined in relation to the Prime Rate, Borrower
may convert all or a portion thereof so that it bears interest determined in
relation to LIBOR for a Fixed Rate Term designated by Borrower. At such time as
Borrower requests an advance hereunder or wishes to select a LIBOR option for
all or a portion of the outstanding principal balance hereof, and at the end of
each Fixed Rate Term, Borrower shall give Bank notice specifying: (a) the
interest rate option selected by Borrower; (b) the principal amount subject
thereto; and (c) for each LIBOR selection, the length of the applicable Fixed
Rate Term. Any such notice may be given by telephone (or such other electronic
method as Bank may permit) so long as, with respect to each LIBOR selection, (i)
if requested by Bank, Borrower provides to Bank written confirmation thereof not
later than 3 Business Days after such notice is given, and (ii) such notice is
given to Bank prior to 10:00 a.m. on the first day of the Fixed Rate Term, or at
a later time during any Business Day if Bank, at it's sole option but without
obligation to do so, accepts Borrower's notice and quotes a fixed rate to
Borrower. If Borrower does not immediately accept a fixed rate when quoted by
Bank, the quoted rate shall expire and any subsequent LIBOR request from
Borrower shall be subject to a redetermination by Bank of the applicable fixed
rate. If no specific designation of interest is made at the time any advance is
requested hereunder or at the end of any Fixed Rate Term, Borrower shall be
deemed to have made a Prime Rate interest selection for such advance or the
principal amount to which such Fixed Rate Term applied.

2.3      Taxes and Regulatory Costs. Borrower shall pay to Bank immediately upon
demand, in addition to any other amounts due or to become due hereunder, any and
all (a) withholdings, interest equalization taxes, stamp taxes or other taxes
(except income and franchise taxes) imposed by any domestic or foreign
governmental authority and related in any manner to LIBOR, and (b) future,
supplemental, emergency or other changes in the LIBOR Reserve Percentage,
assessment rates imposed by the Federal Deposit Insurance Corporation, or
similar requirements or costs imposed by any domestic or foreign governmental
authority or resulting from compliance by Bank with any request or directive
(whether or not having the force of law) from any central bank or other
governmental authority and related in any manner to LIBOR to the extent they are
not included in the calculation of LIBOR. In determining which of the foregoing
are attributable to any LIBOR option available to Borrower hereunder, any
reasonable allocation made by Bank among its operations shall be conclusive and
binding upon Borrower.

2.4      Payment of Interest. Interest accrued on this Note shall be payable on
the 1ST day of each MONTH, commencing JANUARY 1, 2004.

2.5      Default Interest. From and after the maturity date of this Note, or
such earlier date as all principal owing hereunder becomes due and payable by
acceleration or otherwise, the outstanding principal balance of this Note shall
bear interest until paid in full at an increased rate per annum (computed on the
basis of a 360-day year, actual days elapsed) equal to 4% above the rate of
interest from time to time applicable to this Note.

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2.6      Collection of Payments. Borrower authorizes Bank to collect all
interest and fees due hereunder by charging Borrower's deposit account number
4945083079 with Bank, or any other deposit account maintained by any Borrower
with Bank, for the full amount thereof. Should there be insufficient funds in
any such deposit account to pay all such sums when due, the full amount of such
deficiency shall be immediately due and payable by Borrower.

3.       BORROWING AND REPAYMENT:

3.1      Borrowing and Repayment. Borrower may from time to time during the term
of this Note borrow, partially or wholly repay its outstanding borrowings, and
reborrow, subject to all of the limitations, terms and conditions of this Note
and of any document executed in connection with or governing this Note; provided
however, that the total outstanding borrowings under this Note shall not at any
time exceed the principal amount stated above. The unpaid principal balance of
this obligation at any time shall be the total amounts advanced hereunder by the
holder hereof less the amount of principal payments made hereon by or for any
Borrower, which balance may be endorsed hereon from time to time by the holder.
The outstanding principal balance of this Note shall be due and payable in full
on DECEMBER 31, 2004.

3.2      Advances. Advances hereunder, to the total amount of the principal sum
available hereunder, may be made by the holder at the oral or written request of
(a) GREG WEAVER OR INGRID SIMMS, any one acting alone, who are authorized to
request advances and direct the disposition of any advances until written notice
of the revocation of such authority is received by the holder at the office
designated above, or (b) any person, with respect to advances deposited to the
credit of any deposit account of any Borrower, which advances, when so
deposited, shall be conclusively presumed to have been made to or for the
benefit of each Borrower regardless of the fact that persons other than those
authorized to request advances may have authority to draw against such account.
The holder shall have no obligation to determine whether any person requesting
an advance is or has been authorized by any Borrower.

3.3      Application of Payments. Each payment made on this Note shall be
credited first, to any interest then due and second, to the outstanding
principal balance hereof. All payments credited to principal shall be applied
first, to the outstanding principal balance of this Note which bears interest
determined in relation to the Prime Rate, if any, and second, to the outstanding
principal balance of this Note which bears interest determined in relation to
LIBOR, with such payments applied to the oldest Fixed Rate Term first.

4.       PREPAYMENT:

4.1      Prime Rate. Borrower may prepay principal on any portion of this Note
which bears interest determined in relation to the Prime Rate at any time, in
any amount and without penalty.

4.2      LIBOR. Borrower may prepay principal on any portion of this Note which
bears interest determined in relation to LIBOR at any time and in the minimum
amount of $500,000.00; provided however, that if the outstanding principal
balance of such portion of this Note is less than said amount, the minimum
prepayment amount shall be the entire outstanding principal balance thereof. In
consideration of Bank providing this prepayment option to Borrower, or if any
such portion of this Note shall become due and payable at any time prior to the
last day of the Fixed Rate Term applicable thereto by acceleration or otherwise,
Borrower shall pay to Bank immediately upon demand a fee which is the sum of the
discounted monthly differences for each month from the month of prepayment
through the month in which such Fixed Rate Term matures, calculated as follows
for each such month:

         (a)      Determine the amount of interest which would have accrued each
         month on the amount prepaid at the interest rate applicable to such
         amount had it remained outstanding until the last day of the Fixed Rate
         Term applicable thereto.

         (b)      Subtract from the amount determined in (a) above the amount of
         interest which would have accrued for the same month on the amount
         prepaid for the remaining term of such Fixed Rate Term at LIBOR in
         effect on the date of prepayment for new loans made for such term and
         in a principal amount equal to the amount prepaid.

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         (c)      If the result obtained in (b) for any month is greater than
         zero, discount that difference by LIBOR used in (b) above.

Each Borrower acknowledges that prepayment of such amount may result in Bank
incurring additional costs, expenses and/or liabilities, and that it is
difficult to ascertain the full extent of such costs, expenses and/or
liabilities. Each Borrower, therefore, agrees to pay the above-described
prepayment fee and agrees that said amount represents a reasonable estimate of
the prepayment costs, expenses and/or liabilities of Bank. If Borrower fails to
pay any prepayment fee when due, the amount of such prepayment fee shall
thereafter bear interest until paid at a rate per annum 2.000% above the Prime
Rate in effect from time to time (computed on the basis of a 360-day year,
actual days elapsed). Each change in the rate of interest on any such past due
prepayment fee shall become effective on the date each Prime Rate change is
announced within Bank.

5.       EVENTS OF DEFAULT:

         The occurrence of any of the following shall constitute an "Event of
Default" under this Note:

5.1      The failure to pay any principal, interest, fees or other charges when
due hereunder or under any contract, instrument or document executed in
connection with this Note.

5.2      The filing of a petition by or against any Borrower, any guarantor of
this Note or any general partner or joint venturer in any Borrower which is a
partnership or a joint venture (with each such guarantor, general partner and/or
joint venturer referred to herein as a "Third Party Obligor") under any
provisions of the Bankruptcy Reform Act, Title 11 of the United States Code, as
amended or recodified from time to time, or under any similar or other law
relating to bankruptcy, insolvency, reorganization or other relief for debtors;
the appointment of a receiver, trustee, custodian or liquidator of or for any
part of the assets or property of any Borrower or Third Party Obligor; any
Borrower or Third Party Obligor becomes insolvent, makes a general assignment
for the benefit of creditors or is generally not paying its debts as they become
due; or any attachment or like levy on any property of any Borrower or Third
Party Obligor.

5.3      The death or incapacity of any individual Borrower or Third Party
Obligor, or the dissolution or liquidation of any Borrower or Third Party
Obligor which is a corporation, partnership, joint venture or other type of
entity.

5.4      Any default in the payment or performance of any obligation, or any
defined event of default, under any provisions of any contract, instrument or
document pursuant to which any Borrower or Third Party Obligor has incurred any
obligation for borrowed money, any purchase obligation, or any other liability
of any kind to any person or entity, including the holder.

5.5      Any financial statement provided by any Borrower or Third Party Obligor
to Bank proves to be incorrect, false or misleading in any material respect.

5.6      Any sale or transfer of all or a substantial or material part of the
assets of any Borrower or Third Party Obligor other than in the ordinary course
of its business.

5.7      Any violation or breach of any provision of, or any defined event of
default under, any addendum to this Note or any loan agreement, guaranty,
security agreement, deed of trust, mortgage or other document executed in
connection with or securing this Note.

6.       MISCELLANEOUS:

6.1      Remedies. Upon the occurrence of any Event of Default, the holder of
this Note, at the holder's option, may declare all sums of principal and
interest outstanding hereunder to be immediately due and payable without
presentment, demand, notice of nonperformance, notice of protest, protest or
notice of dishonor, all of which are expressly waived by each Borrower, and the
obligation, if any, of the holder to extend any further credit hereunder shall
immediately cease and terminate. Each Borrower shall pay to the holder

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immediately upon demand the full amount of all payments, advances, charges,
costs and expenses, including reasonable attorneys' fees (to include outside
counsel fees and all allocated costs of the holder's in-house counsel), expended
or incurred by the holder in connection with the enforcement of the holder's
rights and/or the collection of any amounts which become due to the holder under
this Note, and the prosecution or defense of any action in any way related to
this Note, including without limitation, any action for declaratory relief,
whether incurred at the trial or appellate level, in an arbitration proceeding
or otherwise, and including any of the foregoing incurred in connection with any
bankruptcy proceeding (including without limitation, any adversary proceeding,
contested matter or motion brought by Bank or any other person) relating to any
Borrower or any other person or entity.

6.2      Obligations Joint and Several. Should more than one person or entity
sign this Note as a Borrower, the obligations of each such Borrower shall be
joint and several.

6.3      Governing Law, This Note shall be governed by and construed in
accordance with the laws of the State of Washington.

7.       ARBITRATION:

7.1      Arbitration. The parties hereto agree, upon demand by any party, to
submit to binding arbitration all claims, disputes and controversies between or
among them (and their respective employees, officers, directors, attorneys, and
other agents), whether in tort, contract or otherwise arising out of or relating
to in any way (a) the loan and related loan and security documents which are the
subject of this Note and its negotiation, execution, collateralization,
administration, repayment, modification, extension, substitution, formation,
inducement, enforcement, default or termination; or (b) requests for additional
credit.

7.2      Governing Rules. Any arbitration proceeding will (a) proceed in a
location in Washington selected by the American Arbitration Association ("AAA");
(b) be governed by the Federal Arbitration Act (Title 9 of the United States
Code), notwithstanding any conflicting choice of law provision in any of the
documents between the parties; and (c) be conducted by the AAA, or such other
administrator as the parties shall mutually agree upon, in accordance with the
AAA's commercial dispute resolution procedures, unless the claim or counterclaim
is at least $1,000,000.00 exclusive of claimed interest, arbitration fees and
costs in which case the arbitration shall be conducted in accordance with the
AAA's optional procedures for large, complex commercial disputes (the commercial
dispute resolution procedures or the optional procedures for large, complex
commercial disputes to be referred to, as applicable, as the "Rules"). If there
is any inconsistency between the terms hereof and the Rules, the terms and
procedures set forth herein shall control. Any party who fails or refuses to
submit to arbitration following a demand by any other party shall bear all costs
and expenses incurred by such other party in compelling arbitration of any
dispute. Nothing contained herein shall be deemed to be a waiver by any party
that is a bank of the protections afforded to it under 12 U.S.C. Section 91 or
any similar applicable state law.

7.3      No Waiver of Provisional Remedies, Self-Help and Foreclosure. The
arbitration requirement does not limit the right of any party to (a) foreclose
against real or personal property collateral; (b) exercise self-help remedies
relating to collateral or proceeds of collateral such as setoff or repossession;
or (c) obtain provisional or ancillary remedies such as replevin, injunctive
relief, attachment or the appointment of a receiver, before during or after the
pendency of any arbitration proceeding. This exclusion does not constitute a
waiver of the right or obligation of any party to submit any dispute to
arbitration or reference hereunder, including those arising from the exercise of
the actions detailed in sections (a), (b) and (c) of this paragraph.

7.4      Arbitrator Qualifications and Powers. Any arbitration proceeding in
which the amount in controversy is $5,000,000.00 or less will be decided by a
single arbitrator selected according to the Rules, and who shall not render an
award of greater than $5,000,000.00. Any dispute in which the amount in
controversy exceeds $5,000,000.00 shall be decided by majority vote of a panel
of three arbitrators; provided however, that all three arbitrators must actively
participate in all hearings and deliberations. The arbitrator will be a neutral
attorney licensed in the State of Washington or a neutral retired judge of the
state or federal judiciary of

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Washington, in either case with a minimum of ten years experience in the
substantive law applicable to the subject matter of the dispute to be
arbitrated. The arbitrator will determine whether or not an issue is
arbitratable and will give effect to the statutes of limitation in determining
any claim. In any arbitration proceeding the arbitrator will decide (by
documents only or with a hearing at the arbitrator's discretion) any pre-hearing
motions which are similar to motions to dismiss for failure to state a claim or
motions for summary adjudication. The arbitrator shall resolve all disputes in
accordance with the substantive law of Washington and may grant any remedy or
relief that a court of such state could order or grant within the scope hereof
and such ancillary relief as is necessary to make effective any award. The
arbitrator shall also have the power to award recovery of all costs and fees, to
impose sanctions and to take such other action as the arbitrator deems necessary
to the same extent a judge could pursuant to the Federal Rules of Civil
Procedure, the Washington Rules of Civil Procedure or other applicable law.
Judgment upon the award rendered by the arbitrator may be entered in any court
having jurisdiction. The institution and maintenance of an action for judicial
relief or pursuit of a provisional or ancillary remedy shall not constitute a
waiver of the right of any party, including the plaintiff, to submit the
controversy or claim to arbitration if any other party contests such action for
judicial relief.

7.5      Discovery. In any arbitration proceeding discovery will be permitted in
accordance with the Rules. All discovery shall be expressly limited to matters
directly relevant to the dispute being arbitrated and must be completed no later
than 20 days before the hearing date and within 180 days of the filing of the
dispute with the AAA. Any requests for an extension of the discovery periods, or
any discovery disputes, will be subject to final determination by the arbitrator
upon a showing that the request for discovery is essential for the party's
presentation and that no alternative means for obtaining information is
available.

7.6      Class Proceedings and Consolidations. The resolution of any dispute
arising pursuant to the terms of this Note shall be determined by a separate
arbitration proceeding and such dispute shall not be consolidated with other
disputes or included in any class proceeding.

7.7      Payment Of Arbitration Costs And Fees. The arbitrator shall award all
costs and expenses of the arbitration proceeding.

7.8      Miscellaneous. To the maximum extent practicable, the AAA, the
arbitrators and the parties shall take all action required to conclude any
arbitration proceeding within 180 days of the filing of the dispute with the
AAA. No arbitrator or other party to an arbitration proceeding may disclose the
existence, content or results thereof, except for disclosures of information by
a party required in the ordinary course of its business or by applicable law or
regulation. If more than one agreement for arbitration by or between the parties
potentially applies to a dispute, the arbitration provision most directly
related to the documents between the parties or the subject matter of the
dispute shall control. This Note may be amended or modified only in writing
signed by each party hereto. If any provision of this Note shall be held to be
prohibited by or invalid under applicable law such provision shall be
ineffective only to the extent of such prohibition or invalidity, without
invalidating the remainder of such provision or any remaining provisions of this
Note. This arbitration provision shall survive termination, amendment or
expiration of any of the documents or any relationship between the parties.

ORAL AGREEMENTS OR ORAL COMMITMENTS TO LOAN MONEY, EXTEND CREDIT OR TO FORBEAR
ENFORCING REPAYMENT OF A DEBT ARE NOT ENFORCEABLE UNDER WASHINGTON LAW.

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IN WITNESS WHEREOF, the undersigned has executed this Note as of the date first
written above.

Nastech Pharmaceutical Company Inc.

By:/s/ Steven Quay
   ---------------------------
    Steven Quay, CEO

By:/s/ Greg Weaver
   ---------------------------
    Greg Weaver, CPO

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