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                                                                     Exhibit 4.4

                               PURCHASE AGREEMENT

                  THIS PURCHASE AGREEMENT ("Agreement") is made as of the 16th
day of December, 1999 by and between Avi BioPharma, Inc., a corporation
organized under the laws of Oregon, with headquarters located at Portland,
Oregon (the "Company"), and the persons identified on the signature pages hereto
(each an "Investor" and collectively, the "Investors").

                                    RECITALS

                  A. The Company and the Investors are executing and delivering
this Agreement in reliance upon the exemption from securities registration
afforded by the provisions of Regulation D ("Regulation D"), as promulgated by
the U.S. Securities and Exchange Commission (the "SEC") under the Securities Act
of 1933, as amended;

                  B. The Investors wish to purchase, and the Company wishes to
sell and issue to the Investors, upon the terms and conditions stated in this
Agreement, certain of the Company's shares of Common Stock, par value $.0001 per
share (the "Common Stock") and warrants to acquire shares of Common Stock in the
form attached hereto as EXHIBIT A (the "Warrants") for an aggregate purchase
price of $4.0 million; and

                  C. Contemporaneous with the execution and delivery of this
Agreement, the parties hereto are executing and delivering a Registration Rights
Agreement, in the form attached hereto as EXHIBIT B (the "Registration Rights
Agreement"), pursuant to which the Company has agreed to provide certain
registration rights under the Securities Act of 1933, as amended, and the rules
and regulations promulgated thereunder, and applicable state securities laws;

                  In consideration of the mutual promises made herein and for
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, the parties hereto agree as follows:

         1. DEFINITIONS. In addition to those terms defined above and elsewhere
in this Agreement, for the purposes of this Agreement, the following terms shall
have the meanings here set forth:

                  1.1 "AFFILIATE" means, with respect to any Person, any other
Person which directly or indirectly controls, is controlled by, or is under
common control with, such Person.

                  1.2 "AGREEMENTS" means this Agreement, the Registration Rights
Agreement, and the Warrants


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                  1.3 "CLOSING" means the consummation of the transactions
contemplated by this Agreement, and "CLOSING DATE" means the date of such
Closing.

                  1.4 "CONTROL" means the possession , direct or indirect, of
the power to direct or cause the direction of the management and policies of a
person, whether through the ownership of voting securities, by contract or
otherwise.

                  1.5 "MARKET PRICE" means the average of the lowest ten (10)
closing bid prices of the Common Stock over the immediately preceding thirty
(30) trading days as reported by NASDAQ National Market ("the Nasdaq Stock
Market").

                  1.6 "MATERIAL ADVERSE EFFECT" means a material adverse effect
on the (i) condition (financial or otherwise), business, assets, or results of
operations of the Company and its subsidiaries, taken as a whole; (ii) ability
of the Company to perform any of its material obligations under the Agreements;
or (iii) rights and remedies of the Investor under the Agreements.

                  1.7 "PERSON" means an individual, corporation, partnership,
trust, business trust, association, joint stock company, joint venture, pool,
syndicate, sole proprietorship, unincorporated organization, governmental
authority or any other form of entity not specifically listed herein.

                  1.8 "SEC FILINGS" has the meaning set forth in Section 4.6.

                  1.9 "SECURITIES" means the Shares, the Warrants and the
Warrant Shares (defined below).

                  1.10 "SHARES" means the shares of Common Stock being purchased
by the Investor hereunder.

                  1.11 "WARRANT SHARES" means the shares of Common Stock
issuable upon exercise of or otherwise pursuant to the Warrants.

                  1.12 "1933 ACT" means the Securities Act of 1933, as amended,
and the rules and regulations promulgated thereunder.

                  1.13 "1934 ACT" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations promulgated thereunder.

         2. PURCHASE AND SALE OF THE SHARES AND WARRANTS. Subject to the terms
and conditions of this Agreement, each Investor severally hereby agrees to
purchase and the Company hereby agrees to sell and issue to such Investor, the
number of Shares and Warrants to purchase the number of shares of Common Stock
set forth on such Investor's signature page attached hereto. The number of
Shares to be purchased by such Investor shall be determined by dividing such
Investor's aggregate purchase price (as the aggregate purchase price is set
forth on such Investor's signature page attached hereto), by an amount equal to
75% of the Market Price



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of the Common Stock on the date hereof (the "Purchase Price"); provided that the
Purchase Price shall not be less than $3.50 per share nor more than $4.00 per
share (subject to appropriate adjustment for stock splits, reverse splits,
dividends and distributions), and the aggregate Purchase Price shall not exceed
$5.0 million. The number of shares of Common Stock purchasable by the Investor
pursuant to the Warrants shall be equal to 30% of the number of Shares purchased
by the Investor, with an initial exercise price equal to 115% of the Market
Price on the date hereof.

         3. CLOSING. On the date of this Agreement, the Purchase Price shall be
determined. The Company shall promptly deliver to Kleinberg, Kaplan, Wolff &
Cohen, P.C. ("KKWC"), on the date hereof, in trust, (i) the Warrants and a
certificate registered in such name or names as the Investor may designate,
representing all of the Shares, and (ii) payment in full of the fees and
expenses referred to in Section 10.5(b) and (c) below, with instructions that
such certificates, Warrants and dollar amounts are to be held for release to an
Investor only upon payment of the applicable Purchase Price by such Investor to
the Company. Upon receipt by KKWC of the certificates, the Warrants and dollar
amounts, each Investor shall promptly cause a wire transfer in same day funds to
be sent to the account of the Company as instructed in writing by the Company,
in amounts representing such Investor's aggregate Purchase Price. On the date
the Company receives funds from an Investor, the certificates evidencing the
Shares and the Warrants shall be released to such Investor and the allocable
dollar amounts shall be released to the payees as contemplated by Sections 10.5
(b) and (c)(and such date, as to such Investor, shall be deemed the "Closing
Date").

         4. REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company hereby
represents and warrants to the Investors that:

                  4.1 ORGANIZATION, GOOD STANDING AND QUALIFICATION. The Company
is a corporation duly incorporated, validly existing and in good standing under
the laws of Oregon and has all requisite power and authority to carry on its
business and own its properties as now conducted and owned. The Company is duly
qualified or licensed to do business as a foreign corporation and is in good
standing in each jurisdiction in which the conduct of its business or its
ownership or leasing of property makes such qualification or licensing necessary
unless the failure to so qualify or be licensed would not have a Material
Adverse Effect. SCHEDULE 4.1 lists all subsidiaries of the Company. Except when
the context otherwise requires, representations and warranties in this Section 4
by the Company shall be deemed to include representations and warranties as to
its subsidiaries as well.

                  4.2 AUTHORIZATION. The Company has full power and authority
and has taken all requisite action on the part of the Company, its officers,
directors and stockholders necessary for (i) the authorization, execution and
delivery of the Agreements, (ii) the performance of all obligations of the
Company hereunder or thereunder, and (iii) the authorization, issuance (or
reservation for issuance) and delivery of the Securities. The Agreements
constitute the legal, valid and binding obligations of the Company, enforceable
against the Company in accordance with their terms, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization,



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moratorium and similar laws of general applicability, relating to or affecting
creditors' rights generally.

                  4.3 CAPITALIZATION. Set forth on SCHEDULE 4.3 hereto is (a)
the authorized capital stock of the Company on the date hereof; (b) the number
of shares of capital stock issued and outstanding; (c) the number of shares of
capital stock issuable pursuant to the Company's stock plans; and (d) the number
of shares of capital stock issuable and reserved for issuance pursuant to
securities (other than the Shares and the Warrants) exercisable for, or
convertible into or exchangeable for any shares of capital stock. All of the
issued and outstanding shares of the Company's capital stock have been duly
authorized and validly issued and are fully paid, nonassessable and free of
preemptive rights. Except as set forth on SCHEDULE 4.3, no Person is entitled to
preemptive or similar statutory or contractual rights with respect to any
securities of the Company, including the Shares, the Warrants and the Warrant
Shares. Except as set forth on SCHEDULE 4.3, there are no outstanding warrants,
options, convertible securities or other rights, agreements or arrangements of
any character under which the Company is or may be obligated to issue any equity
securities of any kind, or to transfer any equity securities of any kind, and
except as contemplated by this Agreement, the Company does not have any present
plan or intention to issue any equity securities of any kind, or to transfer any
equity securities of any kind owned by it. Except as set forth on SCHEDULE 4.3,
the Company does not know of any voting agreements, buy-sell agreements, option
or right of first purchase agreements or other agreements of any kind among any
of the securityholders of the Company relating to the securities held by them.
Except as set forth on SCHEDULE 4.3, the Company has not granted any Person the
right to require the Company to register any securities of the Company under the
1933 Act, whether on a demand basis or in connection with the registration of
securities of the Company for its own account or for the account of any other
Person.

                  4.4 VALID ISSUANCE. The Company has reserved a sufficient
number of shares of Common Stock for issuance pursuant to this Agreement and
upon exercise of the Warrants. The Company will take such steps as may be
necessary to reserve sufficient shares for issuance pursuant to Section 7 below
when such issuance is determinable. The Shares and Warrants are duly authorized,
and such Securities, along with the Warrant Shares when issued in accordance
herewith and with the terms of the Warrants, will be duly authorized, validly
issued, fully paid, non-assessable and free and clear of all encumbrances and
restrictions, except for restrictions on transfer imposed by applicable
securities laws.

                  4.5 CONSENTS. The execution, delivery and performance by the
Company of the Agreements and the offer, issuance and sale of the Securities
require no consent of, action by or in respect of, or filing with, any Person,
governmental body, agency, or official other than (i) filings that have been
made pursuant to applicable state securities laws and the requirements of the
Nasdaq Stock Market and (ii) post-sale filings pursuant to applicable state and
federal securities laws and the requirements of the Nasdaq Stock Market which
the Company undertakes to file within the applicable time periods.

                  4.6 DELIVERY OF SEC FILINGS; BUSINESS. The Company has
provided each Investor with copies of the Company's most recent Annual Report on
Form 10K for the fiscal


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year ended December 31, 1998, and all other reports filed by the Company
pursuant to the 1934 Act since the filing of the Annual Report on Form 10K
(collectively, the "SEC Filings"). The Company is engaged only in the business
described in the SEC Filings and the SEC Filings contain a complete and accurate
description of the business of the Company. The Company has not provided to any
Investor (i) any information required to be filed under the 1934 Act that has
not been so filed or (ii) any non-public information.

                  4.7 USE OF PROCEEDS. The proceeds of the sale of the
Securities hereunder shall be used by the Company for working capital and
general corporate purposes.

                  4.8 NO MATERIAL ADVERSE CHANGE. Since the filing of the
Company's most recent Annual Report on Form 10K or as otherwise identified and
described in subsequent reports filed by the Company pursuant to the 1934 Act,
there has not been:

                         (i) any change in the consolidated assets, liabilities,
financial condition or operating results of the Company from that reflected in
the financial statements included in the Company's most recent Report on Form
10Q, except changes in the ordinary course of business which have not had, in
the aggregate, a Material Adverse Effect;

                         (ii) any declaration or payment of any dividend, or any
authorization or payment of any distribution, on any of the capital stock of the
Company, or any redemption or repurchase of any securities of the Company;

                         (iii) any material damage, destruction or loss, whether
or not covered by insurance to any assets or properties of the Company or any of
its subsidiaries;

                         (iv) any waiver by the Company of a valuable right or
of a material debt owed to it;

                         (v) any satisfaction or discharge of any lien, claim or
encumbrance or payment of any obligation by the Company, except in the ordinary
course of business and which is not material to the assets, properties,
financial condition, operating results or business of the Company taken as a
whole (as such business is presently conducted and as it is proposed to be
conducted);

                         (vi) any material change or amendment to a material
contract or arrangement by which the Company or any of its assets or properties
is bound or subject;

                         (vii) any labor difficulties or labor union organizing
activities with respect to employees of the Company;

                         (viii) any transaction entered into by the Company
other than in the ordinary course of business; or

                         (ix) any other event or condition of any character that
might have a Material Adverse Effect.


<PAGE>


                  4.9 SEC FILINGS; MATERIAL CONTRACTS.

                         (a) As of its filing date, each report filed by the
Company with the SEC pursuant to the 1934 Act, complied as to form in all
material respects with the requirements of the 1934 Act and did not contain any
untrue statement of a material fact or omit to state any material fact necessary
in order to make the statements made therein, in the light of the circumstances
under which they were made, not misleading.

                         (b) Each registration statement and any amendment
thereto filed by the Company pursuant to the 1933 Act and the rules and
regulations thereunder, as of the date such statement or amendment became
effective, complied as to form in all material respects with the 1933 Act and
did not contain any untrue statement of a material fact or omit to state any
material fact required to be stated therein or necessary to make the statements
therein, in light of the circumstances under which they were made, not
misleading; and each prospectus filed pursuant to Rule 424(b) under the 1933
Act, as of its issue date and as of the closing of any sale of securities
pursuant thereto did not contain any untrue statement of a material fact or omit
to state any material fact necessary in order to make the statements made
therein, in the light of the circumstances under which they were made, not
misleading.

                         (c) Except as set forth on SCHEDULE 4.3 hereto, there
are no agreements or instruments currently in force and effect that constitute a
warrant, option, convertible security or other right, agreement or arrangement
of any character under which the Company is or may be obligated to issue any
material amounts of any equity security of any kind, or to transfer any material
amounts of any equity security of any kind.

                  4.10 FORM S-3 ELIGIBILITY.

                  The Company is currently eligible to register the resale of
its Common Stock on a registration statement on Form S-3 under the 1933 Act.

                  4.11 NO CONFLICT, BREACH, VIOLATION OR DEFAULT. (a) The
execution, delivery and performance of the Agreements by the Company and the
issuance and sale of the Securities will not conflict with or result in a breach
or violation of any of the terms and provisions of, or constitute a default
under (i) the Company's Certificate of Incorporation ("Articles") or Bylaws,
each as in effect on the date hereof, or (ii) except where it would not have a
Material Adverse Effect, (a) any statute, rule, regulation or order of any
governmental agency or body or any court, domestic or foreign, having
jurisdiction over the Company or any of its properties, or (b) any agreement or
instrument to which the Company is a party or by which the Company is bound or
to which any of the properties of the Company are subject.

                         (b) Except as set forth on SCHEDULE 4.11 hereto, or
where it would not have a Material Adverse Effect, the Company (i) is not in
violation of any statute, rule or regulation applicable to the Company or its
assets, (ii) is not in violation of any judgment, order or decree applicable to
the Company or its assets; and (iii) is not in breach or violation of any
agreement, note or instrument to which it or its assets are a party or are
bound. The Company



<PAGE>

has not received notice from any Person of any claim or investigation that, if
adversely determined, would render the preceding sentence untrue or incomplete.

                  4.12 TAX MATTERS. The Company has correctly and timely
prepared and filed or timely obtained extensions for, all tax returns required
to have been filed by it with all appropriate governmental agencies and timely
paid all taxes owed by it. The charges, accruals and reserves on the books of
the Company in respect of taxes for all fiscal periods are adequate in all
material respects, and there are no material unpaid assessments of the Company
nor, to the knowledge of the Company, any basis for the assessment of any
additional taxes, penalties or interest for any fiscal period or audits by any
federal, state or local taxing authority except such as which are not material.
All material taxes and other assessments and levies that the Company is required
to withhold or to collect for payment have been duly withheld and collected and
paid to the proper governmental entity or third party. There are no tax liens or
claims pending or threatened against the Company or any of its assets or
property. There are no outstanding tax sharing agreements or other such
arrangements between the Company and any other corporation or entity.

                  4.13 TITLE TO PROPERTIES. Except as disclosed in the SEC
Filings, the Company has good and marketable title to all real properties and
all other properties and assets owned by it, in each case free from liens,
encumbrances and defects that would materially affect the value thereof or
materially interfere with the use made or currently planned to be made thereof
by them; and except as disclosed in the SEC Filings, the Company holds any
leased real or personal property under valid and enforceable leases with no
exceptions that would materially interfere with the use made or currently
planned to be made thereof by them.

                  4.14 CERTIFICATES, AUTHORITIES AND PERMITS. The Company
possesses adequate certificates, authorizations or permits issued by appropriate
governmental agencies or bodies necessary to conduct its business as presently
operated and has not received any written notice of proceedings relating to the
revocation or modification of any such certificate, authority or permit that, if
determined adversely to the Company, would individually or in the aggregate have
a Material Adverse Effect.

                  4.15 NO LABOR DISPUTES. No labor dispute with the employees of
the Company or any subsidiary exists or, to the knowledge of the Company, is
imminent.

                  4.16 INTELLECTUAL PROPERTY. The Company owns or possesses
adequate trademarks and trade names and have all other rights to inventions,
know-how, patents, copyrights, trademarks, trade names, confidential information
and other intellectual property (collectively, "Intellectual Property Rights"),
free and clear of all liens, security interests, charges, encumbrances, equities
and other adverse claims, necessary to conduct the business now operated by it,
or presently employed by it, and presently contemplated to be operated by it,
and has not received any notice of infringement of or conflict with asserted
rights of others with respect to any Intellectual Property Rights. SCHEDULE 4.16
sets forth a list by serial number and title of the patents and/or patent
applications owned or possessed by the Company. No proprietary technology of any
Person was used in the design or development by the Company of



<PAGE>

(or otherwise with respect to) any of the Intellectual Property Rights, which
technology was not properly acquired by the Company from such Person.

                  4.17 ENVIRONMENTAL MATTERS. The Company is not in violation of
any statute, rule, regulation, decision or order of any governmental agency or
body or any court, U.S. or foreign, relating to the use, disposal or release of
hazardous or toxic substances or relating to the protection or restoration of
the environment or human exposure to hazardous or toxic substances
(collectively, "Environmental Laws"), does not own or operate any real property
contaminated with any substance that is subject to any Environmental Laws, is
not liable for any off-site disposal or contamination pursuant to any
Environmental Laws, and is not subject to any claim relating to any
Environmental Laws, which violation, contamination, liability or claim would
individually or in the aggregate have a Material Adverse Effect; and the Company
is not aware of any pending investigation that might lead to such a claim.

                  4.18 LITIGATION. Except as disclosed in the SEC Filings, there
are no pending actions, suits or proceedings against or affecting the Company,
or any of its properties that, if determined adversely to the Company, would
individually or in the aggregate have a Material Adverse Effect or would
materially and adversely affect the ability of the Company to perform its
obligations under the Agreements, or which are otherwise material in the context
of the sale of the Securities; and to the Company's knowledge, no such actions,
suits or proceedings are threatened or contemplated.

                  4.19 FINANCIAL STATEMENTS. The financial statements included
in each SEC Filing present fairly and accurately the consolidated financial
position of the Company as of the dates shown and its results of operations and
cash flows for the periods shown, and such financial statements have been
prepared in conformity with generally accepted accounting principles applied on
a consistent basis. Except as set forth on SCHEDULE 4.19 or in the financial
statements of the Company included in the SEC Filings filed prior to the date
hereof, the Company has no liabilities, contingent or otherwise, except those
which individually or in the aggregate are not material to the financial
condition or operating results of the Company.

                  4.20 INSURANCE COVERAGE. The Company maintains in full force
and effect insurance coverage that is customary for comparably situated
companies for the business being conducted, and properties owned or leased, by
the Company, and the Company reasonably believes such insurance coverage to be
adequate against all liabilities, claims and risks against which it is customary
for comparably situated companies to insure.

                  4.21 COMPLIANCE WITH NASDAQ CONTINUED LISTING REQUIREMENTS.
The Company is in compliance with all applicable Nasdaq continued listing
requirements for the Nasdaq Stock Market and is listed in good standing on the
Nasdaq Stock Market. There are no proceedings pending or, to the Company's
knowledge, threatened against the Company relating to the continued listing of
the Company's Common Stock on the Nasdaq Stock Market and the Company has not
received any notice of, nor to the knowledge of the Company is there any basis
for, the delisting of the Common Stock from the Nasdaq Stock Market.


<PAGE>


                  4.22 ACKNOWLEDGEMENT OF DILUTION. The number of shares of
Common Stock issuable pursuant to this Agreement may increase significantly. The
Company's executive officers and directors have studied and fully understand the
nature of the transactions being contemplated hereunder and recognize that they
have a potential dilutive effect.

                  4.23 BROKERS AND FINDERS. The Investors shall have no
liability or responsibility for the payment of any commission or finder's fee to
any third party in connection with or resulting from this agreement or the
transactions contemplated by this Agreement by virtue of any agreement made by
the Company to a third party, and except as set forth in Section 10.5 below, the
Company shall have no such liability or responsibility for any such commission
or finder's fee.

                  4.24 NO DIRECTED SELLING EFFORTS OR GENERAL SOLICITATION.
Neither the Company nor, to its knowledge, any Person acting on its behalf has
conducted any general solicitation or general advertising (as those terms are
used in Regulation D) in connection with the offer or sale of any of the
Securities.

                  4.25 NO INTEGRATED OFFERING. Neither the Company nor any of
its Affiliates, nor any Person acting on its or their behalf has, directly or
indirectly, made any offers or sales of any security or solicited any offers to
buy any security, under circumstances that would adversely affect reliance by
the Company on Section 4(2) for the exemption from registration for the
transactions contemplated hereby or would require registration of the Securities
under the 1933 Act; or would require the integration of this offering with any
other offering of securities for purposes of determining the need to obtain
shareholder approval of the transactions contemplated hereby under the rules of
the Nasdaq Stock Market.

                  4.26 DISCLOSURES. No representation or warranty made under any
Section hereof and no information furnished by the Company pursuant hereto, or
in any other document, certificate or statement furnished by the Company to the
Investors or any authorized representative of any of the Investors, pursuant to
the Agreements or in connection therewith, contains any untrue statement of a
material fact or omits to state a material fact necessary to make the respective
statements contained herein or therein, in light of the circumstances under
which the statements were made, not misleading.

                  4.27 CORPORATE PARTNER FINANCING. In the fourth quarter of
calendar year 1999 the Company closed a transaction with a strategic investor
which included the purchase by such investor of 1.0 million shares of Common
Stock at $5.00 per share. The Company has received the full $5 million
investment, and the 1.0 million shares have been issued and are outstanding.

         5. REPRESENTATIONS AND WARRANTIES OF THE INVESTOR. Each Investor hereby
severally represents and warrants to the Company as to itself that:

                  5.1 ORGANIZATION AND EXISTENCE. The Investor is a validly
existing company and has all requisite corporate or limited liability company
power and authority to invest in the Securities pursuant to this Agreement.


<PAGE>


                  5.2 AUTHORIZATION. The execution, delivery and performance by
the Investor of the Agreements have been duly authorized and the Agreements will
each constitute the valid and legally binding obligation of the Investor,
enforceable against the Investor in accordance with their terms.

                  5.3 PURCHASE ENTIRELY FOR OWN ACCOUNT. The Securities to be
received by the Investor hereunder will be acquired for the Investor's own
account, not as nominee or agent, and not with a view to the resale or
distribution of any part thereof in violation of securities laws, and the
Investor has no present intention of selling, granting any participation in, or
otherwise distributing the same in violation of securities laws. The Investor is
not a registered broker dealer or an entity engaged in the business of being a
broker dealer.

                  5.4 INVESTMENT EXPERIENCE. The Investor acknowledges that it
can bear the economic risk and complete loss of its investment in the Securities
and has such knowledge and experience in financial and business matters that it
is capable of evaluating the merits and risks of the investment contemplated
hereby.

                  5.5 DISCLOSURE OF INFORMATION. The Investor has had an
opportunity to receive documents related to the Company and to ask questions of
and receive answers from the Company regarding the Company, its business and the
terms and conditions of the offering of the Securities. Neither such inquiries
nor any other due diligence investigation conducted by the Investor shall
modify, amend or affect the Investor's right to rely on the Company's
representations and warranties contained in this Agreement or made pursuant to
this Agreement.

                  5.6 RESTRICTED SECURITIES. The Investor understands that the
Securities are characterized as "restricted securities" under the U.S. federal
securities laws inasmuch as they are being acquired from the Company in a
transaction not involving a public offering and that under such laws and
applicable regulations such securities may be resold without registration under
the 1933 Act only in certain limited circumstances.

                  5.7 LEGENDS. It is understood that, until registration for
resale pursuant to the Registration Rights Agreement or until sales under Rule
144 are permitted, certificates evidencing the Securities will bear one or all
of the following legends or legends substantially similar thereto:

                  "These securities have not been registered under the
Securities Act of 1933, as amended (the "Act"), and may not be offered, sold,
pledged, hypothecated, assigned or transferred except (i) pursuant to a
registration statement under the Act which has become effective and is current
with respect to these securities, or (ii) pursuant to a specific exemption from
registration under the Act but only upon a holder hereof first having obtained
the written opinion of counsel to the Corporation, or other counsel reasonably
acceptable to the Corporation, that the proposed disposition is consistent with
all applicable provisions of the Act."

                  Upon registration for resale pursuant to the Registration
Rights Agreement, or when sales under Rule 144 are permitted, the Company shall
promptly cause certificates



<PAGE>

evidencing the Shares previously issued hereunder to be replaced with
certificates which do not bear such restrictive legends.

                  5.8 ACCREDITED INVESTOR. The Investor is an accredited
investor as defined in Rule 501(a) of Regulation D, as amended, under the 1933
Act.

                  5.9 NO GENERAL SOLICITATION. The Investor did not learn of the
investment in the Securities as a result of any public advertising or general
solicitation.

         6. REGISTRATION RIGHTS AGREEMENT. The parties acknowledge and agree
that part of the inducement for the Investors to enter into this Agreement is
the Company's execution and delivery of the Registration Rights Agreement. The
parties acknowledge and agree that simultaneously with the execution hereof, the
Registration Rights Agreement is being duly executed and delivered by the
parties thereto.

         7. COVENANTS AND AGREEMENTS OF THE COMPANY.

                  7.1 SUBSEQUENT SALE AT LOWER PRICE.

                         (a) REQUIRED ADJUSTMENTS. Subject to the exclusions
contained in Section 7.1(f) below, if during the period ending on the later of
(i) thirty-six (36) months following the Closing Date or (ii) thirty-three (33)
months following the effective date of the Registration Statement contemplated
by the Registration Rights Agreement (the "MFN Period"), the Company sells any
shares of its Common Stock at a per share selling price ("Per Share Selling
Price") lower than the Purchase Price per share set forth in Section 2 hereof,
the Purchase Price per share of the Shares originally sold to an Investor
hereunder shall be adjusted downward to equal such lower Per Share Selling Price
and such Investor shall be entitled to receive the additional shares as provided
by Section 7.1(c); provided, however, that in the event the Investor then owns
less than 51% of the Shares originally acquired by it hereunder, such Investor
shall be entitled to additional shares only with respect to the number of Shares
originally acquired and then owned by the Investor as provided in Section
7.1(c). For so long as such Investor owns 51% or more of the Shares originally
acquired by such Investor hereunder, the Investor shall be entitled to the full
benefit of the Purchase Price adjustment required by this Section 7.1. The
Company shall give to each Investor written notice of any such sale within 24
hours of the closing of any such sale and shall within such 24 hour period issue
a press release announcing such sale.

                         (b) DEFINITIONS.

                            (i) For the purposes of this Section 7.1, the term
"Per Share Selling Price" as used in this Section 7.1 shall mean the amount
actually paid by third parties for each share of Common Stock. A sale of shares
of Common Stock shall include the sale or issuance of rights, options, warrants
or convertible securities ("derivative securities") under which the Company is
or may become obligated to issue shares of Common Stock, and in such
circumstances the sale of Common Stock shall be deemed to have occurred at the
time of the issuance of the derivative securities and the Per Share Selling
Price of the Common Stock



<PAGE>

covered thereby shall also include the exercise or conversion price thereof (in
addition to the consideration per underlying share of Common Stock received by
the Company upon such sale or issuance of the derivative security, less the fee
amount as provided above). In case of any such security issued within the MFN
Period in a "Variable Rate Transaction" or an "MFN Transaction" (each as defined
below), the Per Share Selling Price shall be deemed to be the lowest conversion
or exercise price at which such securities are converted or exercised or might
have been converted or exercised in the case of a Variable Rate Transaction, or
the lowest adjustment price in the case of an MFN Transaction. If shares are
issued for a consideration other than cash, the per share selling price shall be
the fair value of such consideration as determined in good faith by the Board of
Directors of the Company.

                            (ii) The term "Variable Rate Transaction" shall mean
a transaction in which the Company issues or sells (a) any debt or equity
securities that are convertible into, exchangeable or exercisable for, or
include the right to receive additional shares of Common Stock either (x) at a
conversion, exercise or exchange rate or other price that is based upon and/or
varies with the trading prices of or quotations for the Common Stock at any time
after the initial issuance of such debt or equity securities, or (y) with a
fixed conversion, exercise or exchange price that is subject to being reset at
some future date after the initial issuance of such debt or equity security or
upon the occurrence of specified or contingent events directly or indirectly
related to the business of the Company or the market for the Common Stock (but
excluding standard stock split anti-dilution provisions), or (b) any securities
of the Company pursuant to an "equity line" structure which provides for the
sale, from time to time, of securities of the Company which are registered for
resale pursuant to the 1933 Act.

                            (iii) The term "MFN Transaction" shall mean a
transaction in which the Company issues or sells any securities in a capital
raising transaction or series of related transactions (the "New Offering") which
grants to an investor (the "New Investor") the right to receive additional
shares based upon future transactions of the Company on terms more favorable
than those granted to the New Investor in the New Offering.

                            (iv) The term "MFN Period" shall have the meaning
set forth in Section 7.1(a), above.

                            (c) ADJUSTMENT MECHANISM. If an adjustment of the
Purchase Price is required pursuant to Section 7.1(a), the Company shall deliver
to the Investor within eight calendar days of the closing of the transaction
giving rise to the adjustment or by such other date as may be required by
Section 7.1(d) ("Delivery Date") the Investor's share of such number of
additional shares of Common Stock equal to (i) the aggregate Purchase Price paid
by the Investor divided by the adjusted Per Share Purchase Price as required
under Section 7.1(a), minus (ii) the total number of shares of Common Stock
previously delivered to the Investor hereunder; PROVIDED HOWEVER, that the
Company shall delay effecting such adjustment, in whole or in part, to the
extent required by Section 7.1(d). In the event the Company fails to deliver the
additional shares by the applicable Delivery Date, the Company shall be liable
to the Investor for a delay payment equal to 2% of the Purchase Price per month
payable in Common Stock or cash, at the Investor's election. If at the time of
any adjustment the proviso of the first sentence of Section 7.1(a) is
applicable, then the number of additional shares otherwise determined as
deliverable under this Section



<PAGE>

7.1(c) shall be adjusted so that it is equal to such number, multiplied by a
fraction, the numerator of which is the number of Shares acquired on the Closing
Date and still owned at the time of the adjustment and the denominator is the
total number of Shares acquired on the Closing Date.

                         (d) LIMITATION ON NUMBER OF SHARES.

                            (i) If by way of any adjustment required by this
Section 7.1, the Investor would receive a number of shares of Common Stock such
that the total number of such shares beneficially owned (within the meaning of
Section 13(d) of the 1934 Act) by the Investor as of the date of such adjustment
would be greater than 9.90% but less than 13.0% of the total outstanding Common
Stock of the Company, then the Company shall not effect the adjustment required
by this Section to the extent necessary to avoid causing the aforesaid
limitation to be exceeded until 120 days following the date such adjustment
would have otherwise been made.

                            (ii) If by way of any adjustment required by this
Section 7.1, the Investor would receive a number of shares of Common Stock such
that the total number of such shares held by the Investor as of the date of such
adjustment would equal or exceed 13.0% of the total outstanding Common Stock of
the Company, then the Company shall not effect the adjustment required by this
Section to the extent necessary to avoid causing the aforesaid limitation to be
exceeded until 180 days following the date such adjustment would have otherwise
been made.

                            (iii) In no event shall the Company issue to an
Investor additional shares pursuant to an adjustment required by this Section
7.1 such that the total number of shares issued to such Investor (when added to
the Warrant Shares actually received upon exercise of Warrants by such Investor)
would exceed such Investor's "pro rata" share of 2,861,361 shares of Common
Stock (the "allocation") (subject to appropriate adjustment for stock splits or
stock dividends). Instead, the Company shall redeem excess shares at 110% of the
Per Share Purchase Price, as adjusted. At such time as an Investor owns neither
any Shares that were originally acquired pursuant to this Agreement nor any
Warrants, it shall notify the Company, who then shall notify the other
Investors. At such time, to the extent such Investor's allocation has not been
exhausted, it shall be divided, pro rata, among the remaining Investors. An
Investor's pro rata share shall be the portion determined by dividing its
aggregate Purchase Price by the total Purchase Price of all Investors holding
shares at the time the pro rata share is being determined. Each Investor's
initial allocation is listed on the signature page for such Investor. Only
shares acquired pursuant to this Agreement or upon exercise of Warrants will be
included in determining whether the limitations would be exceeded for purposes
of this Section 7.1(d)(iii).

                            (iv) The time periods in paragraphs (i) (120 days)
and (ii) (180 days) above shall be extended one (1) day for each day, prior to
the time that sales under Rule



<PAGE>

144(k) would be permitted, that sales under the Registration Statement
contemplated by the Registration Rights Agreement may not be made.

                         (e) CAPITAL ADJUSTMENTS. In case of any stock split or
reverse stock split, stock dividend, reclassification of the common stock,
recapitalization, merger or consolidation, or like capital adjustment affecting
the Common Stock of the Company, the provisions of Section 7.1 shall be applied
in a fair, equitable and reasonable manner so as to give effect, as nearly as
may be, to the purposes hereof.

                         (f) EXCLUSIONS. Section 7.1(a) shall not apply to (i)
sales of shares of Common Stock by the Company upon conversion or exercise of
any convertible securities, options or warrants outstanding prior to the date
hereof; or (ii) sales of shares of Common Stock by the Company pursuant to the
provisions of any shareholder-approved option or similar plan heretofore adopted
by the Company.

                         (g) RULE 144. The Company agrees to take the position
that, for purposes of determining the holding period under Rule 144 for shares
of Common Stock issued pursuant to Section 7.1(a), the holding period of such
shares shall be tacked to the holding period of the Shares.

                  7.2 LIMITATION ON TRANSACTIONS.

                         (a) Until the expiration of the MFN Period, without the
prior written consent of the Investors (which consent may be withheld in the
Investor's discretion), the Company shall not (i) issue or sell or agree to
issue or sell any securities for cash in a non-public MFN Transaction; or (ii)
issue or sell, or agree to issue or sell, any securities for cash in a
non-public Variable Rate Transaction.

                         (b) During the period after effectiveness of the
registration statement contemplated by the Registration Rights Agreement and
until the expiration of the MFN Period, without the prior written consent of the
Investor (which consent may be withheld in the Investor's discretion), the
Company shall not (i) issue or sell or agree to issue or sell any securities for
cash in a non-public MFN Transaction; or (ii) issue or sell, or agree to issue
or sell, any securities for cash in a non-public Variable Rate Transactions.

                         (c) Except as contemplated by paragraph (e) below, the
Company shall not issue any securities in any transaction that would be
integrated with the Securities issued pursuant to this Agreement.

                         (d) The Company may issue securities pursuant to
"equity line" financing (as described in Section 7.1(b)(ii) above) provided the
number of common shares issued does not exceed 8% of the number of common shares
outstanding on the initiation of the equity line.

                         (e) The Company may issue additional equity securities,
for an aggregate purchase price equal to $3.0 million. There can be no more than
four institutional



<PAGE>

investors ("other investors") in such transaction, who shall be identified to
Tail Wind Inc. If the Company issues such equity with six (6) months of the date
hereof, the allocation provided for in Section 7.1(d)(iii) above shall be
proportionally reduced in a manner acceptable to all the Investors, and each
Investor shall be notified of its new allocation. No more than six institutional
investors will be approached in connection with such transaction. The
transaction with the "other investors" will be on the terms, conditions and
provisions as set forth in the documents supplied to KKWC and Tail Wind Inc. on
December 15, 1999. The Company will supply each Investor with complete copies of
all of the transaction documents applicable to the investment by the other
investors at the time such documents are agreed to by the Company.

                  7.3 RIGHT OF INVESTOR TO PARTICIPATE IN FUTURE TRANSACTIONS.
The Company agrees that during the MFN Period the Investor will have a right to
participate in future non-public capital raising transactions as set forth in
this Section 7.3. The Company shall give advance written notice to each Investor
prior to any offer or sale of any of its equity securities or any securities
convertible into or exchangeable or exercisable for such securities in a
non-public capital raising transaction. Prior to the closing of any such
transaction, each Investor shall have the right to participate in its pro rata
share of up to 50% of such new offering (or in the case of a Variable Rate
Transaction, up to 75% of such new offering) and purchase such securities for
the same consideration and on the same terms and conditions as contemplated for
such third-party sale. In order to exercise this right, an Investor must give
written notice to the Company of the Investor's election to participate and such
notice must be given within ten (10) days following receipt of the notice from
the Company. In the event the Company gives notice to the Investor of an
expected transaction pursuant to this Section 7.3 but cannot consummate such
transaction, the Company will give the Investor prompt written notice of the
cancellation of such transaction. If, subsequent to the Company giving notice to
the Investor hereunder, the terms and conditions of the proposed third-party
sale are changed in any way, the Company shall be required to provide a new
notice to the Investor hereunder and the Investor shall have the right to
participate in the offering on such changed terms and conditions as provided
hereunder.

                  7.4 OPINION OF COUNSEL. On or prior to the Closing Date, the
Company will deliver to the Investor the opinions of independent legal counsel
to the Company, in form and substance reasonably acceptable to the Investor,
addressing those legal matters set forth in SCHEDULE 7.4 hereto.

                  7.5 RESERVATION OF COMMON STOCK PURSUANT TO SECTION 7.1 AND
EXERCISE OF WARRANTS. The Company hereby agrees, at all times with respect to
shares issuable upon exercise of the Warrants, and at all appropriate times with
respect to shares issuable pursuant to Section 7.1, to reserve and keep
available out of its authorized but unissued shares of Common Stock, solely for
the purpose of providing for the additional issuance(s) of Common Stock pursuant
to Section 7.1 and exercise of the Warrants, such number of shares of Common
Stock as shall from time to time equal the number of shares sufficient to permit
the issuance, if any, required pursuant to Section 7.1 plus the number of shares
of Common Stock as shall be necessary to permit the exercise of the Warrants in
accordance with the terms of the Warrants.


<PAGE>


                  7.6 REPORTS. Within one week of filing the following reports
with the SEC, or in the absence of such filing within the time periods specified
below, the Company shall send a copy of the following reports to each Investor
by regular mail:

                         (a) QUARTERLY REPORTS. As soon as available the
Company's quarter-annual report on Form 10-Q or, in the absence of such report,
consolidated balance sheets of the Company and its subsidiaries as at the end of
such period and the related consolidated statements of operations, stockholders'
equity and cash flows for such period and for the portion of the Company's
fiscal year ended on the last day of such quarter, all in reasonable detail and
certified by a principal financial officer of the Company to have been prepared
in accordance with generally accepted accounting principles, subject to year-end
and audit adjustments.

                         (b) ANNUAL REPORTS. As soon as available after the end
of each fiscal year of the Company, the Company's Form 10K or, in the absence of
a Form 10K, consolidated balance sheets of the Company and its subsidiaries as
at the end of such year and the related consolidated statements of earnings,
stockholders' equity and cash flows for such year, all in reasonable detail and
accompanied by the report on such consolidated financial statements of an
independent certified public accountant selected by the Company and reasonably
satisfactory to the Investor.

                         (c) SECURITIES FILINGS. As promptly as practicable and
in any event within one week after the same are issued or filed, copies of (i)
all notices, proxy statements, financial statements, reports and documents as
the Company or any subsidiary shall send or make available generally to its
stockholders or to financial analysts, and (ii) all periodic and special
reports, documents and registration statements which the Company or any
subsidiary furnishes or files, or any officer or director of the Company or any
of its subsidiaries (in such person's capacity as such) furnishes or files with
the SEC.

                         (d) OTHER INFORMATION. Such other information relating
to the Company or its subsidiaries as from time to time may reasonably be
requested by the Investor provided the Company produces such information in its
ordinary course of business, and further provided that the Company, solely in
its own discretion, determines that such information is not confidential in
nature and disclosure to the Investor would not be harmful to the Company.

                         (e) RULE 144. The Company agrees to make publicly
available on a timely basis the information necessary to enable Rule 144 to be
available for resale.

                  7.7 PRESS RELEASES. Any press release or other publicity
concerning this Agreement or the transactions contemplated by this Agreement
shall be submitted to the Investor for comment at least two (2) business days
prior to issuance, unless the release is required to be issued within a shorter
period of time by law or pursuant to the rules of a national securities
exchange. The Company shall issue a press release concerning the fact and
material terms of this Agreement within one business day of the Closing.

                  7.8 NO CONFLICTING AGREEMENTS. The Company will not, and will
not permit its subsidiaries to, take any action, enter into any agreement or
make any commitment that would



<PAGE>

conflict or interfere in any material respect with the obligations to the
Investor under the Agreements.

                  7.9 INSURANCE. For so long as any Investor beneficially owns
any of the Securities, the Company shall, and shall cause each subsidiary to,
have in full force and effect (a) insurance reasonably believed to be adequate
on all assets and activities of a type customarily insured, covering property
damage and loss of income by fire or other casualty, and (b) insurance
reasonably believed to be adequate protection against all liabilities, claims
and risks against which it is customary for companies similarly situated as the
Company and the subsidiaries to insure.

                  7.10 COMPLIANCE WITH LAWS. For so long as any Investor
beneficially owns any of the Securities, the Company will use reasonable
efforts, and will cause each of its subsidiaries to use reasonable efforts, to
comply with all applicable laws, rules, regulations, orders and decrees of all
governmental authorities, except to the extent non-compliance (in one instance
or in the aggregate) would not have a Material Adverse Effect.

                  7.11 LISTING OF UNDERLYING SHARES AND RELATED MATTERS. The
Company hereby agrees, promptly following the Closing of the transactions
contemplated by this Agreement, to take such action to cause the Shares, the
Warrant Shares and the shares of Common Stock issuable under Section 7.1(a)
hereof to be listed on the Nasdaq Stock Market as promptly as possible but no
later than the effective date of the registration contemplated by the
Registration Rights Agreement. The Company further agrees that if the Company
applies to have its Common Stock or other securities traded on any other
principal stock exchange or market, it will include in such application the
Common Stock underlying the Warrants, and will take such other action as is
necessary to cause such Common Stock to be so listed. The Company will take all
action necessary to continue the listing and trading of its Common Stock on the
Nasdaq Stock Market and will comply in all respects with the Company's
reporting, filing and other obligations under the bylaws or rules of such
exchange, as applicable, to ensure the continued eligibility for trading of the
Shares and the Warrant Shares thereon.

                  7.12 CORPORATE EXISTENCE. So long as any Investor beneficially
owns any of the Shares or Warrants, the Company shall maintain its corporate
existence, except in the event of a merger, consolidation or sale of all or
substantially all of the Company's assets, as long as the surviving or successor
entity in such transaction (a) assumes the Company's obligations hereunder and
under the agreements and instruments entered into in connection herewith,
regardless of whether or not the Company would have had a sufficient number of
shares of Common Stock authorized and available for issuance in order to fulfill
its obligations hereunder and effect the exercise in full of all Warrants
outstanding as of the date of such transaction; (b) has no legal, contractual or
other restrictions on its ability to perform the obligations of the Company
hereunder and under the agreements and instruments entered into in connection
herewith; and (c) (i) is a publicly traded corporation whose common stock and
the shares of capital stock issuable upon exercise of the Warrants are (or would
be upon issuance thereof) listed for trading on the Nasdaq Stock Market, New
York Stock Exchange or American Stock Exchange, or (ii) if not such a publicly
traded corporation, then the buyer agrees that it will, at



<PAGE>

the election of the Investor, purchase such Investor's Shares (and Warrant
Shares) at a price equal to 120% of the Per Share Purchase Price of such Shares.

         8. SURVIVAL. All representations, warranties, covenants and agreements
contained in this Agreement shall be deemed to be representations, warranties,
covenants and agreements as of the date hereof and shall survive the execution
and delivery of this Agreement.

         9. ARBITRATION.

                  9.1 SCOPE. Resolution of any and all disputes arising from or
in connection with the Agreements, whether based on contract, tort, common law,
equity, statute, regulation, order or otherwise ("Disputes"), shall be
exclusively governed by and settled in accordance with the provisions of this
Section 9; provided, that the foregoing shall not preclude equitable or other
judicial relief to enforce the provisions hereof or to preserve the status quo
pending resolution of Disputes hereunder.

                  9.2 BINDING ARBITRATION. The parties hereby agree to submit
all Disputes to arbitration for final and binding resolution. Either party may
initiate such arbitration by delivery of a demand therefor (the "Arbitration
Demand") to the other party. The arbitration shall be conducted in New York, New
York by a sole arbitrator selected by agreement of the parties not later than 10
days after delivery of the Arbitration Demand, or, failing such agreement,
appointed pursuant to the Commercial Arbitration Rules of the America
Arbitration Association, as amended from time to time (the "AAA Rules"). If the
arbitrator becomes unable to serve, his successor(s) shall be similarly selected
or appointed.

                  9.3 PROCEDURE. The arbitration shall be conducted pursuant to
the Federal Arbitration Act and such procedures as the parties may agree or, in
the absence of or failing such agreement, pursuant to the AAA Rules.
Notwithstanding the foregoing, (a) each party shall have the right to conduct
limited discovery of information relevant to the Dispute; (b) each party shall
provide to the other, reasonably in advance of any hearing, copies of all
documents that a party intends to present in such hearing; (c) all hearings
shall be conducted on an expedited schedule; and (d) all proceedings shall be
confidential, except that either party may at its expense make a stenographic
record thereof.

                  9.4 TIMING. The arbitrator shall use best efforts to complete
all hearings not later than 90 days after his or her selection or appointment,
and shall use best efforts to make a final award not later than 30 days
thereafter. The arbitrator shall apportion all costs and expenses of the
arbitration, including the arbitrator's fees and expenses, and fees and expenses
of experts ("Arbitration Costs") between the prevailing and non-prevailing party
as the arbitrator shall deem fair and reasonable. In circumstances where a
Dispute has been asserted or defended against on grounds that the arbitrator
deems manifestly unreasonable, the arbitrator may assess all Arbitration Costs
against the non-prevailing party and may include in the award the prevailing
party's attorney's fees and expenses in connection with any and all proceedings
under this Section 9. Notwithstanding the foregoing, in no event may the
arbitrator award multiple or punitive damages


<PAGE>


         10. MISCELLANEOUS.

                  10.1 SUCCESSORS AND ASSIGNS. This Agreement may not be
assigned by a party hereto without the prior written consent of the other party
hereto, except that without the prior written consent of the Company, but after
notice duly given, an Investor may assign its rights hereunder in whole or in
part to any purchaser of Securities from the Investor. The terms and conditions
of this Agreement shall inure to the benefit of and be binding upon the
respective permitted successors and assigns of the parties. Nothing in this
Agreement, express or implied, is intended to confer upon any party other than
the parties hereto or their respective successors and assigns any rights,
remedies, obligations, or liabilities under or by reason of this Agreement,
except as expressly provided in this Agreement.

                  10.2 COUNTERPARTS. This Agreement may be executed in two or
more counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

                  10.3 TITLES AND SUBTITLES. The titles and subtitles used in
this Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

                  10.4 NOTICES. Unless otherwise provided, any notice required
or permitted under this Agreement shall be given in writing and shall be deemed
effectively given only upon delivery to each party to be notified by (i)
personal delivery, (ii) telex or telecopier, upon receipt of the electronically
generated confirmation of delivery, or (iii) a recognized overnight air courier,
addressed to the party to be notified at the address as follows, or at such
other address as such party may designate by ten days' advance written notice to
the other party:

                           If to the Company:

                                    Avi BioPharma, Inc.
                                    One SW Columbia Street, Suite 1105
                                    Portland, Oregon  97258
                                    Telephone: (503) 227-0554
                                    Telefax:   (503) 227-0751
                                    Attention: Alan P. Timmins
                                               Chief Financial Officer


<PAGE>


                                    with a copy to:

                                    Ater Wynne
                                    222 SW Columbia, Suite 1800
                                    Portland, Oregon 97201
                                    Attention:       Byron Milstead
                                    Telephone:       (503) 226-1191
                                    Facsimile:       (503) 226-0079

                           If to the Investor:

                           To the address specified therefor on the applicable
signature pages.

                                    and with a copy to:

                                    Kleinberg, Kaplan, Wolff & Cohen, P.C.
                                    551 Fifth Avenue
                                    New York, New York  10176
                                    Attn:  Stephen M. Schultz
                                    Telephone: (212) 986-6000
                                    Facsimile: (212) 986-8866

                  10.5 FEES AND EXPENSES.

                         (a) Except as set forth below, the parties hereto shall
pay their own costs and expenses in connection herewith.

                         (b) European American Securities, Inc. (EASI), a member
firm of the NASD, and a regulated entity of the Securities and Futures Authority
of Great Britain, will act as agent for the Investor in the transaction. EASI
shall be entitled to a fee equal to $0.28 per share, which shall be paid by the
Company at the Closing.

                         (c) Tail Wind Inc. shall receive an expense allowance
to cover due diligence expenses and legal expenses, in an amount equal to 1% of
the aggregate Purchase Price (not to exceed $40,000) less the portion of the
expense allowance previously paid ($13,000). Such expense allowance shall be
paid by the Company at the Closing.

                  10.6 AMENDMENTS AND WAIVERS. Any term of this Agreement may be
amended and the observance of any term of this Agreement may be waived (either
generally or in a particular instance and either retroactively or
prospectively), only with the written consent of the Company and 75% in interest
(based upon pro rata share) of the Investors. Any amendment or waiver effected
in accordance with this paragraph shall be binding upon each holder of any
Securities purchased under this Agreement at the time outstanding, each future
holder of all such securities, and the Company.


<PAGE>


                  10.7 SEVERABILITY. If one or more provisions of this Agreement
are held to be unenforceable under applicable law, such provision shall be
excluded from this Agreement and the balance of this Agreement shall be
interpreted as if such provision were so excluded and shall be enforceable in
accordance with its terms.

                  10.8 ENTIRE AGREEMENT. This Agreement, including the Exhibits
and Schedules hereto, and the Registration Rights Agreement constitute the
entire agreement among the parties hereof with respect to the subject matter
hereof and thereof and supersede all prior agreements and understandings, both
oral and written, between the parties with respect to the subject matter hereof
and thereof.

                  10.9 FURTHER ASSURANCES. The parties shall execute and deliver
all such further instruments and documents and take all such other actions as
may reasonably be required to carry out the transactions contemplated hereby and
to evidence the fulfillment of the agreements herein contained.

                  10.10 APPLICABLE LAW. This Agreement shall be governed by, and
construed in accordance with, the laws of the State of New York without regard
to principles of conflicts of laws.

                  10.11 REMEDIES.

                         (a) The Investors shall be entitled to specific
performance of the Company's obligations under the Agreements.

                         (b) The Company shall indemnify each Investor and each
such Investor's officers, directors, partners, agents and employees
(collectively, "Indemnitees") and hold the Indemnitees harmless from any loss,
cost, expense or fees (including attorneys' fees and expenses) arising out of
(i) any breach of any representation, warranty, covenant or agreement in any of
the Agreements, (ii) any cause of action, suit or claim brought or made against
such Indemnitee (other than directly by the Company solely for breach of this
Purchase Agreement, the Warrant, or the Registration Rights Agreement by the
Indemnitee or by governmental or regulatory authorities), and arising out of or
resulting from (whether in whole or in part) the execution, delivery,
performance or enforcement of the Agreements or any other instrument, document
or agreement executed pursuant hereto or thereto or contemplated hereby or
thereby (including without limitation the acquisition of the Warrants and/or the
Warrant Shares), any transaction financed or to be financed in whole or in part,
directly or indirectly, with the proceeds of the issuance of the Securities or
the status of the purchaser as an investor in the Company, except to the extent
that such actual loss or damage directly results from a breach by such
Indemnitee of the Agreements or from a violation of law, or (iii) arising out of
the enforcement of this Section 10.11. The right to indemnification shall
include the right to advancement of expenses as they are incurred.


<PAGE>


                  IN WITNESS WHEREOF, the parties have executed this Agreement
as of the date first above written.

The Company:

                                      AVI BIOPHARMA, INC.

                                      By:_________________________
                                      Name:
                                      Title:

The Investor:                         THE TAIL WIND FUND, LTD.

                                      By:_________________________
                                      Name:
                                      Title:

                                      By:_________________________
                                      Name:
                                      Title:

Aggregate Purchase Price:  $2,500,000
Number of Shares of Common Stock:  714,286
Number of Warrants:  214,286
Effective per share Purchase Price of Shares:  $3.50
Exercise price of Warrants:  $4.03
Share Allocation 1,788,351 (per Section 7.1(d)(iii))
Address for Notice:

The Tail Wind Fund, Ltd.            With copies to:
Windermere House
404 East Bay Street                 Tail Wind, Inc
P.O. Box SS-5539                    C/o European American Securities, Inc.
Nassau, Bahamas                     One Regent Street, 4th Floor
Attn:  J. McCarroll                 London SW1Y 4NS
Telephone:  242/393-8777            England
Facsimile:   242/393-9021           Attn:  David Crook
                                    Telephone:  44-171-468-7660
                                    Facsimile:   44-171-468-7657

                                    Kleinberg, Kaplan, Wolff & Cohen, P.C.
                                    551 Fifth Avenue
                                    New York, New York  10176
                                    Attn:  Stephen M. Schultz
                                    Telephone: (212) 986-6000
                                    Facsimile: (212) 986-8866




                              [PURCHASE AGREEMENT]


<PAGE>


                  IN WITNESS WHEREOF, the parties have executed this Agreement
as of the date first above written.

The Company:

                                        AVI BIOPHARMA, INC.

                                        By:_________________________
                                        Name:
                                        Title:

The Investor:                           RESONANCE LTD.

                                        By:_________________________

Name:  Mo Bodner

                                        Title:

Aggregate Purchase Price:  $1,500,000
Number of Shares of Common Stock:  428,571
Number of Warrants:  128,571
Effective per share Purchase Price of Shares:  $3.50
Exercise price of Warrants:  $4.03
Share Allocation 1,073,010 (per Section 7.1(d)(iii))
Address for Notice:

                            Resonance Ltd.
                            c/o International Securities Corporation
                            551 Fifth Avenue
                            Suite 1425
                            New York, New York 10176
                            Attn: Mo Bodner
                            Telephone: (212) 986-7811
                            Facsimile:





                              [PURCHASE AGREEMENT]


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                                 EXHIBIT 7.2(e)

                   TERMS FOR PRIVATE PLACEMENT OF COMMON STOCK
                             OF AVI BIOPHARMA, INC.

ISSUE SIZE:                                          $3.0 million.

PRICING:                                             A 25% discount off the
                                                     market price prior to the
                                                     close of the transaction,
                                                     with the "Market Price"
                                                     defined as the average of
                                                     the lowest 10 closing bid
                                                     prices out of a 30 trading
                                                     day period; however, in no
                                                     event will the purchase
                                                     price be below $3.50 or
                                                     above $4.00.

WARRANTS:                                            30% coverage in 5 year
                                                     warrants with a strike
                                                     price at a 15% premium to
                                                     the Market Price prior to
                                                     the close of the
                                                     transaction.

ANTI DILUTION PROTECTION:                            MFN provision no more
                                                     favorable to the investors
                                                     than those included in the
                                                     agreement with The Tail
                                                     Wind Fund Ltd.

REGISTRATION:                                        The company will file a
                                                     registration statement for
                                                     resale for the shares
                                                     issued, and if this is not
                                                     declared effective within 3
                                                     months, penalties will
                                                     accrue at the rate of 2%
                                                     per month.

FEE:                                                 To be agreed between the
                                                     parties.


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                                  SCHEDULE 4.1

AntiVirals Acquisition Corp., a California corporation, a wholly-owned
subsidiary if AVI BioPharma, Inc.


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                                  SCHEDULE 4.11

No items to report


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                                  SCHEDULE 4.19

No items to report.


<PAGE>



                                  SCHEDULE 4.3

(a)      50,000,000 shares of Common Stock authorized 2,000,000 shares of
         Preferred Stock authorized

(b)      14,378,698 shares of Common Stock issued and outstanding no shares of
         Preferred Stock issued and outstanding

(c)      2,144,277 shares of Common Stock issuable pursuant to stock option
         plans

(d)      4,898,681 shares of Common Stock issuable pursuant to warrant
         agreements