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NEITHER THESE SECURITIES NOR THE SECURITIES INTO WHICH THESE SECURITIES ARE
EXERCISABLE HAVE BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR
THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE UPON AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES
ACT"), AND, ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT TO AN
AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION
REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE
SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO
SUCH EFFECT, THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE
COMPANY. THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE
SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT OR OTHER
LOAN SECURED BY SUCH SECURITIES.

AVI BIOPHARMA, INC.

WARRANT

Warrant No. [    ]   Date of Original Issuance: March 25, 2002

        AVI BioPharma, Inc., an Oregon corporation (the "Company"), hereby
certifies that, for value received, [Name of Holder] or its registered assigns
(the "Holder"), is entitled to purchase from the Company up to a total
of            1 shares of common stock, $.0001 par value per share (the "Common
Stock"), of the Company (each such share, a "Warrant Share" and all such shares,
the "Warrant Shares") at an exercise price (as adjusted from time to time as
provided in Section 9, the "Exercise Price") per Warrant Share equal to $9.00 at
any time and from time to time from and after the date hereof and through and
including March 24, 2006 (the "Expiration Date"), and subject to the following
terms and conditions:

        1. Definitions. In addition to the terms defined elsewhere in this
Warrant, capitalized terms that are not otherwise defined herein and that are
defined in the Securities Purchase Agreement, dated as of March 25, 2002,
between the Company and the original Holder (the "Purchase Agreement"), shall
have the meanings given to such terms in the Purchase Agreement. .

        2. Registration of Warrant. The Company shall register this Warrant,
upon records to be maintained by the Company for that purpose (the "Warrant
Register"), in the name of the record Holder hereof from time to time. The
Company may deem and treat the registered Holder of this Warrant as the absolute
owner hereof for the purpose of any exercise hereof or any distribution to the
Holder, and for all other purposes, absent actual notice to the contrary.

        3. Registration of Transfers. The Company shall register the transfer of
any portion of this Warrant in the Warrant Register, upon surrender of this
Warrant, with the Form of Assignment attached hereto duly completed and signed,
to the Transfer Agent or to the Company at its address specified herein. Upon
any such registration or transfer, a new warrant to purchase Common Stock, in
substantially the form of this Warrant (any such new warrant, a "New Warrant"),
evidencing the portion of this Warrant so transferred shall be issued to the
transferee and a New Warrant evidencing the remaining portion of this Warrant
not so transferred, if any, shall be issued to the transferring Holder. The
acceptance of the New Warrant by the transferee thereof shall be deemed the
acceptance by such transferee of all of the rights and obligations of a holder
of a Warrant.

        4. Exercise and Duration; Early Call

        (a) Subject to the provisions of Section 4(b), this Warrant shall be
exercisable by the registered Holder at any time and from time to time on or
after the date hereof to and including the Expiration Date. At 6:30 p.m., New
York City time, on the Expiration Date, the portion of this Warrant available
for exercise and not exercised prior thereto shall be and become void and of no
value.

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        (b) If at any time after September 24, 2003 (18 months following the
Closing Date] (1) the closing price per share of the Common Stock as reported on
Bloomberg has exceeded 200% of the Exercise Price then in effect for a period of
ten (10) consecutive Trading Days (the "Determination Period") and (2) a
registration statement covering resales of the Common Stock issuable upon
exercise of the Warrants has been effective and available for use at all times
required pursuant to the Registration Rights Agreement and is expected to remain
effective and available for use until at least the last date on which the
registration statement is required to be kept effective under the terms of the
Registration Rights Agreement, then the Company may, at its sole option, provide
all of the Holders irrevocable written notice ("Call Notice") requiring all of
the Holders to fully exercise all Warrants as of the Call Date (as defined
below). If all of the conditions described herein have been satisfied and
continue to be satisfied through the Call Date, any Warrant not exercised before
the close of business on the Call Date, shall automatically be deemed exercised
in accordance with Section 5(a) as of the close of trading on the Call Date and
the Company will deliver the Warrant Shares to the Holder upon receipt of a
completed Exercise Notice along with the original copy of the Warrant for
cancellation (or an affidavit of lost Warrant in accordance with Section 12) and
payment for the Warrant Shares as provided herein. "Call Date" shall mean that
Trading Day that is at least thirty (30) days following the date on which the
Company has given the Call Notice to the Holders.

        5. Delivery of Warrant Shares.

        (a) Upon delivery of the Form of Election to Purchase (in the form of
Exhibit A) ("Exercise Notice") to the Company (with the Warrant Shares Exercise
Log in the form of Exhibit B hereto) at its address for notice set forth in
Section 13 and (i) upon payment of the Exercise Price multiplied by the number
of Warrant Shares that the Holder intends to purchase hereunder or (ii) upon
notifying the Company that this Warrant is being exercised pursuant to a
Cashless Exercise (as defined in Section 5(e)), the Company shall promptly (but
in no event later than three (3) Trading Days after the Date of Exercise (as
defined herein)) issue and deliver to the Holder, a certificate for the Warrant
Shares issuable upon such exercise free of restrictive legends unless otherwise
required by the Purchase Agreement. The Company shall, upon request of the
Holder, if available, use its best efforts to deliver Warrant Shares hereunder
electronically through the Depository Trust Corporation.

        A "Date of Exercise" means the date on which the Holder shall have
delivered to the Company (i) the Form of Election to Purchase (with the Warrant
Exercise Log attached to it), appropriately completed and duly signed and
(ii) (A) payment of the Exercise Price for the number of Warrant Shares so
indicated by the Holder to be purchased or (B) notification to the Company that
this Warrant is being exercised pursuant to a Cashless Exercise.

        (b)  If by the fifth Trading Day after a Date of Exercise the Company
fails to deliver the required number of Warrant Shares in the manner required
pursuant to Section 5(a), then the Holder will have the right to rescind such
exercise.

        (c)  If by the third Trading Day after a Date of Exercise the Company
fails to deliver the required number of Warrant Shares in the manner required
pursuant to Section 5(a), and if after such fifth Trading Day the Holder
purchases (in an open market transaction or otherwise) shares of Common Stock to
deliver in satisfaction of a sale by the Holder of the Warrant Shares which the
Holder anticipated receiving upon such exercise (a "Buy-In"), then the Company
shall (1) pay in cash to the Holder the amount by which (x) the Holder's total
purchase price (including brokerage commissions, if any) for the shares of
Common Stock so purchased exceeds (y) the amount obtained by multiplying (A) the
number of Warrant Shares that the Company was required to deliver to the Holder
in connection with the exercise at issue by (B) the closing price of the Common
Stock at the time of the obligation giving rise to such purchase obligation and
(2) at the option of the Holder, either reinstate the portion of the Warrant and
equivalent number of Warrant Shares for which such exercise was not honored or
deliver to the Holder the number of

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shares of Common Stock that would have been issued had the Company timely
complied with its exercise and delivery obligations hereunder. For example, if
the Holder purchases Common Stock having a total purchase price of $11,000 to
cover a Buy-In with respect to an attempted exercise of shares of Common Stock
with a market price on the date of exercise totaled $10,000, under clause (1) of
the immediately preceding sentence the Company shall be required to pay the
Holder $1,000. The Holder shall provide the Company written notice, which notice
shall include such supporting documentation as reasonably necessary to
substantiate the amounts payable, indicating the amounts payable to the Holder
in respect of the Buy-In.

        (d)  The Company's obligations to issue and deliver Warrant Shares in
accordance with the terms hereof are absolute and unconditional, irrespective of
any action or inaction by the Holder to enforce the same, any waiver or consent
with respect to any provision hereof, the recovery of any judgment against any
Person or any action to enforce the same, or any setoff, counterclaim,
recoupment, limitation or termination, or any breach or alleged breach by the
Holder or any other Person of any obligation to the Company or any violation or
alleged violation of law by the Holder or any other Person, and irrespective of
any other circumstance which might otherwise limit such obligation of the
Company to the Holder in connection with the issuance of Warrant Shares. Nothing
herein shall limit a Holder's right to pursue any other remedies available to it
hereunder, at law or in equity including, without limitation, a decree of
specific performance and/or injunctive relief with respect to the Company's
failure to timely deliver certificates representing shares of Common Stock upon
exercise of the Warrant as required pursuant to the terms hereof.

        (e)  If, despite the Company's obligations under the Purchase Agreement
and the Registration Rights Agreement, the Warrant Shares to be issued are not
registered and available for resale pursuant to an effective registration
statement in accordance with the Registration Rights Agreement within the
timeframes provided therein, then, notwithstanding anything contained herein to
the contrary, the Holder of this Warrant may, at its election exercised in its
sole discretion, exercise this Warrant in whole or in part and, in lieu of
paying the Exercise Price in cash, elect instead to receive upon such exercise
the "Net Number" of shares of Common Stock determined according to the following
formula (a "Cashless Exercise"):

Net Number = (A × B) - (A × C)
B     For purposes of the foregoing formula: A= the total number of shares with
respect to which this Warrant is then being exercised;
B= the greater of the (i) closing price per share of the Common Stock (as
reported by Bloomberg) on the Trading Day immediately preceding the date of the
Exercise Notice or (ii) the average of the closing prices per share of Common
Stock (as reported by Bloomberg) for the ten (10) Trading Days immediately
preceding the date of the Exercise Notice; and
C= the Exercise Price then in effect for the applicable Warrant Shares at the
time of such exercise.

        6. Charges, Taxes and Expenses. Issuance and delivery of certificates
for shares of Common Stock upon exercise of this Warrant shall be made without
charge to the Holder for any issue or transfer tax, withholding tax, transfer
agent fee or other incidental tax or expense in respect of the issuance of such
certificates, all of which taxes and expenses shall be paid by the Company;
provided, however, that the Company shall not be required to pay any tax which
may be payable in respect of any transfer involved in the registration of any
certificates for Warrant Shares or Warrants in a name other than that of the

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Holder. The Holder shall be responsible for all other tax liability that may
arise as a result of holding or transferring this Warrant or receiving Warrant
Shares upon exercise hereof.

        7. Replacement of Warrant. If this Warrant is mutilated, lost, stolen or
destroyed, the Company shall issue or cause to be issued in exchange and
substitution for and upon cancellation hereof, or in lieu of and substitution
for this Warrant, a New Warrant, but only upon receipt of evidence reasonably
satisfactory to the Company of such loss, theft or destruction and customary and
reasonable indemnity, if requested. Applicants for a New Warrant under such
circumstances shall also comply with such other reasonable regulations and
procedures and pay such other reasonable third-party costs as the Company may
prescribe.

        8. Reservation of Warrant Shares. The Company covenants that it will at
all times reserve and keep available out of the aggregate of its authorized but
unissued and otherwise unreserved Common Stock, solely for the purpose of
enabling it to issue Warrant Shares upon exercise of this Warrant as herein
provided, the number of Warrant Shares which are then issuable and deliverable
upon the exercise of this entire Warrant. The Company covenants that all Warrant
Shares so issuable and deliverable shall, upon issuance and the payment of the
applicable Exercise Price in accordance with the terms hereof, be duly and
validly authorized, issued and fully paid and nonassessable.

        9. Certain Adjustments. The Exercise Price and number of Warrant Shares
issuable upon exercise of this Warrant are subject to adjustment from time to
time as set forth in this Section 9.

        (a)  Stock Dividends and Splits. If the Company, at any time while this
Warrant is outstanding, (i) pays a stock dividend on its Common Stock or
otherwise makes a distribution on any class of capital stock that is payable in
shares of Common Stock, (ii) subdivides outstanding shares of Common Stock into
a larger number of shares, or (iii) combines outstanding shares of Common Stock
into a smaller number of shares, then in each such case the Exercise Price shall
be multiplied by a fraction of which the numerator shall be the number of shares
of Common Stock outstanding immediately before such event and of which the
denominator shall be the number of shares of Common Stock outstanding
immediately after such event.

        (b)  Pro Rata Distributions. If the Company, at any time while this
Warrant is outstanding, distributes to all holders of Common Stock (i) evidences
of its indebtedness, (ii) any security (other than a distribution of Common
Stock covered by the preceding paragraph), (iii) rights or warrants to subscribe
for or purchase any security, or (iv) any other asset (in each case,
"Distributed Property"), then, at the request of any Holder delivered before the
90th day after the record date fixed for determination of stockholders entitled
to receive such distribution, the Company will deliver to such Holder, within
five (5) Trading Days after such request (or, if later, on the effective date of
such distribution), the Distributed Property that such Holder would have been
entitled to receive in respect of the Warrant Shares for which such Holder's
Warrant could have been exercised immediately prior to such record date. If such
Distributed Property is not delivered to a Holder pursuant to the preceding
sentence, then upon any exercise of the Warrant that occurs after such record
date, such Holder shall be entitled to receive, in addition to the Warrant
Shares otherwise issuable upon such conversion, the Distributed Property that
such Holder would have been entitled to receive in respect of such number of
Warrant Shares had the Holder been the record holder of such Warrant Shares
immediately prior to such record date.

        (c)  Fundamental Transactions. If, at any time while this Warrant is
outstanding: (i) the Company effects any merger or consolidation of the Company
with or into another Person, (ii) the Company effects any sale of all or
substantially all of its assets in one or a series of related transactions,
(iii) any tender offer or exchange offer (whether by the Company or another
Person) is completed pursuant to which holders of Common Stock are permitted to
tender or exchange their shares for other securities, cash or property, or
(iv) the Company effects any reclassification of the Common Stock or any
compulsory share exchange pursuant to which the Common Stock is

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effectively converted into or exchanged for other securities, cash or property
(in any such case, a "Fundamental Transaction"), then the Holder shall have the
right thereafter to receive, upon exercise of this Warrant, the same amount and
kind of securities, cash or property as it would have been entitled to receive
upon the occurrence of such Fundamental Transaction if it had been, immediately
prior to such Fundamental Transaction, the holder of the number of Warrant
Shares then issuable upon exercise in full of this Warrant (the "Alternate
Consideration"). For purposes of any such exercise, the determination of the
Exercise Price shall be appropriately adjusted to apply to such Alternate
Consideration based on the amount of Alternate Consideration issuable in respect
of one (1) share of Common Stock in such Fundamental Transaction, and the
Company shall apportion the Exercise Price among the Alternate Consideration in
a reasonable manner reflecting the relative value of any different components of
the Alternate Consideration. If holders of Common Stock are given any choice as
to the securities, cash or property to be received in a Fundamental Transaction,
then the Holder shall be given the same choice as to the Alternate Consideration
it receives upon any exercise of this Warrant following such Fundamental
Transaction. At the Holder's option and request, any successor to the Company or
surviving entity in such Fundamental Transaction shall issue to the Holder a new
warrant substantially in the form of this Warrant and consistent with the
foregoing provisions and evidencing the Holder's right to purchase the Alternate
Consideration for the aggregate Exercise Price upon exercise thereof. The terms
of any agreement pursuant to which a Fundamental Transaction is effected shall
include terms requiring any such successor or surviving entity to comply with
the provisions of this paragraph (c) and insuring that the Warrant (or any such
replacement security) will be similarly adjusted upon any subsequent transaction
analogous to a Fundamental Transaction.

        (d)  Subsequent Equity Sales.

(i)If at any time while this Warrant is outstanding, the Company or any
subsidiary thereof, as applicable with respect to Common Stock Equivalents (as
defined below), shall issue shares of Common Stock or rights, warrants, options
or other securities or debt that is convertible into or exercisable or
exchangeable for shares of Common Stock ("Common Stock Equivalents"), entitling
any person to acquire shares of Common Stock at a price per share less than the
Exercise Price (if the holder of the Common Stock or Common Stock Equivalent so
issued shall at any time, whether by operation of purchase price adjustments,
reset provisions, floating conversion, exercise or exchange prices or otherwise,
or due to warrants, options or rights issued in connection with such issuance,
be entitled to receive shares of Common Stock at a price less than the Exercise
Price, such issuance shall be deemed to have occurred for less than the Exercise
Price), (such lower price shall be referred to herein as the "New Sale Price"
and such issuance shall be referred to herein as a "New Sale Issuance"); then,
the Exercise Price will be reduced to the New Sale Price, whenever such Common
Stock or Common Stock Equivalents are issued; provided, if there is more than
one New Sale Issuance, the Exercise Price shall be adjusted to the lowest of the
New Sale Prices. The number of shares of Common Stock covered by such Warrants
would not be adjusted, except for adjustments otherwise required under other
subparagraphs of this Section 9, such as subsections (a) or (b). The price
adjustment provisions in this Section 9(d)(i) are not intended to apply to the
sale or issuance of Common Stock arising from the exercise of any rights, of
whatsoever nature, as such rights exist as of the Closing Date and disclosed in
Schedule 3.1(g) of the Purchase Agreement.

(ii)If, at any time while this Warrant is outstanding, the Company or any
Subsidiary issues Common Stock Equivalents at a price per share that floats or
resets or otherwise varies or is subject to adjustment based on market prices of
the Common Stock (a "Floating Price Security"), then for purposes of applying
the preceding paragraph in connection

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with any subsequent exercise, the Exercise Price will be determined separately
on each Date of Exercise and will be deemed to equal the lowest price per share
at which any holder of such Floating Price Security is entitled to acquire
shares of Common Stock on such Date of Exercise (regardless of whether any such
holder actually acquires any shares on such date).

        Notwithstanding the foregoing, no adjustment will be made under this
paragraph (d) in respect of (i) the granting of options to employees, officers
and directors of the Company pursuant to any stock option plan duly adopted by
the Company prior to the date hereof or to the issuance of Common Stock upon
exercise of such options or (ii) issuances of shares of Common Stock pursuant to
a Strategic Transaction. A "Strategic Transaction" shall mean a transaction or
relationship in which the Company issues Common Stock to a Person which is,
itself or through its subsidiaries, an operating company in a business related
to the business of the Company and in which the Company receives material
benefits in addition to the investment of funds, but shall not include a
transaction in which the Company is issuing securities primarily for the purpose
of raising capital or to an entity whose primary business is investing in
securities.

        (e)  Number of Warrant Shares. Simultaneously with any adjustment to the
Exercise Price pursuant to paragraphs (a) or (b) of this Section, the number of
Warrant Shares that may be purchased upon exercise of this Warrant shall be
increased or decreased proportionately, so that after such adjustment the
aggregate Exercise Price payable hereunder for the adjusted number of Warrant
Shares shall be the same as the aggregate Exercise Price in effect immediately
prior to such adjustment.

        (f)    Calculations. All calculations under this Section 9 shall be made
to the nearest cent or the nearest 1/100th of a share, as applicable. The number
of shares of Common Stock outstanding at any given time shall not include shares
owned or held by or for the account of the Company, and the disposition of any
such shares shall be considered an issue or sale of Common Stock.

        (g)  Notice of Adjustments. Upon the occurrence of each adjustment
pursuant to this Section 9, the Company at its expense will promptly compute
such adjustment in accordance with the terms of this Warrant and prepare a
certificate setting forth such adjustment, including a statement of the adjusted
Exercise Price and adjusted number or type of Warrant Shares or other securities
issuable upon exercise of this Warrant (as applicable), describing the
transactions giving rise to such adjustments and showing in detail the facts
upon which such adjustment is based. Upon written request, the Company will
promptly deliver a copy of each such certificate to the Holder and to the
Company's Transfer Agent.

        (h)  Notice of Corporate Events. If the Company (i) declares a dividend
or any other distribution of cash, securities or other property in respect of
its Common Stock, including without limitation any granting of rights or
warrants to subscribe for or purchase any capital stock of the Company or any
Subsidiary, (ii) authorizes or approves, enters into any agreement contemplating
or solicits stockholder approval for any Fundamental Transaction or
(iii) authorizes the voluntary dissolution, liquidation or winding up of the
affairs of the Company, then the Company shall deliver to the Holder a notice
describing the material terms and conditions of such transaction, at least
twenty (20) calendar days prior to the applicable record or effective date on
which a Person would need to hold Common Stock in order to participate in or
vote with respect to such transaction, and the Company will take all steps
reasonably necessary in order to insure that the Holder is given the practical
opportunity to exercise this Warrant prior to such time so as to participate in
or vote with respect to such transaction; provided, however, that the failure to
deliver such notice or any defect therein shall not affect the validity of the
corporate action required to be described in such notice and provided that such
information shall be publicly

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disclosed pursuant to Regulation FD prior to or in conjunction with such notice
being provided to the Holder.

        10. Payment of Exercise Price. The Holder shall pay the Exercise Price
in cash by delivering immediately available funds or, if permitted by
Section 5(e), through a Cashless Exercise.

        11. Limitation on Exercise.

        (a)  Notwithstanding anything to the contrary contained herein, the
number of shares of Common Stock that may be acquired by the Holder upon any
exercise of this Warrant (or otherwise in respect hereof) shall be limited to
the extent necessary to insure that, following such exercise (or other
issuance), the total number of shares of Common Stock then beneficially owned by
such Holder and its Affiliates and any other Persons whose beneficial ownership
of Common Stock would be aggregated with the Holder's for purposes of
Section 13(d) of the Exchange Act, does not exceed 4.999% of the total number of
issued and outstanding shares of Common Stock (including for such purpose the
shares of Common Stock issuable upon such exercise). For such purposes,
beneficial ownership shall be determined in accordance with Section 13(d) of the
Exchange Act and the rules and regulations promulgated thereunder. Each delivery
of an Exercise Notice hereunder will constitute a representation by the Holder
that it has evaluated the limitation set forth in this paragraph and determined
that issuance of the full number of Warrant Shares requested in such Exercise
Notice is permitted under this paragraph. By written notice to the Company, the
Holder may waive the provisions of this Section but (i) any such waiver will not
be effective until the 61st day after such notice is delivered to the Company,
and (ii) any such waiver will apply only to the Holder and not to any other
holder of Warrants.

        (b)  Notwithstanding anything to the contrary contained herein, the
number of shares of Common Stock that may be acquired by the Holder upon any
exercise of this Warrant (or otherwise in respect hereof) shall be limited to
the extent necessary to insure that, following such exercise (or other
issuance), the total number of shares of Common Stock then beneficially owned by
such Holder and its Affiliates and any other Persons whose beneficial ownership
of Common Stock would be aggregated with the Holder's for purposes of
Section 13(d) of the Exchange Act, does not exceed 9.999% of the total number of
issued and outstanding shares of Common Stock (including for such purpose the
shares of Common Stock issuable upon such exercise). For such purposes,
beneficial ownership shall be determined in accordance with Section 13(d) of the
Exchange Act and the rules and regulations promulgated thereunder. Each delivery
of an Exercise Notice hereunder will constitute a representation by the Holder
that it has evaluated the limitation set forth in this paragraph and determined
that issuance of the full number of Warrant Shares requested in such Exercise
Notice is permitted under this paragraph. By written notice to the Company, the
Holder may waive the provisions of this Section but (i) any such waiver will not
be effective until the 61st day after such notice is delivered to the Company,
and (ii) any such waiver will apply only to the Holder and not to any other
holder of Warrants.

        12. No Fractional Shares. No fractional shares of Warrant Shares will be
issued in connection with any exercise of this Warrant. In lieu of any
fractional shares which would, otherwise be issuable, the Company shall pay cash
equal to the product of such fraction multiplied by the closing price of one
Warrant Share as reported on the Eligible Market on the date of exercise.

        13. Notices. Any and all notices or other communications or deliveries
hereunder (including without limitation any Exercise Notice or Call Notice)
shall be in writing and shall be deemed given and effective on the earliest of
(i) the date of transmission, if such notice or communication is delivered via
facsimile at the facsimile number specified in this Section prior to 6:30 p.m.
(New York City time) on a Trading Day, (ii) the next Trading Day after the date
of transmission, if such notice or communication is delivered via facsimile at
the facsimile number specified in this Section on a day that is not a Trading
Day or later than 6:30 p.m. (New York City time) on any Trading Day, (iii) the
Trading

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Day following the date of mailing, if sent by nationally recognized overnight
courier service, or (iv) upon actual receipt by the party to whom such notice is
required to be given. The addresses for such communications shall be: (i) if to
the Company, to AVI BioPharma, Inc., One S.W. Columbia, Suite 1105, Portland,
Oregon 97258, Attention: Alan P. Timmins (facsimile: 503-227-0751) with a copy
to Hurley, Lynch & Re, P.C., 747 SW Industrial Way, Bend, OR 97702, Attention:
Robert A. Stout, Esq. (facsimile: 541-317-5507) or (ii) if to the Holder, to the
address or facsimile number appearing on the Warrant Register or such other
address or facsimile number as the Holder may provide to the Company in
accordance with this Section.

        14. Warrant Agent. The Company shall serve as warrant agent under this
Warrant. Upon thirty (30) days' notice to the Holder, the Company may appoint a
new warrant agent. Any corporation into which the Company or any new warrant
agent may be merged or any corporation resulting from any consolidation to which
the Company or any new warrant agent shall be a party or any corporation to
which the Company or any new warrant agent transfers substantially all of its
corporate trust or shareholders services business shall be a successor warrant
agent under this Warrant without any further act. Any such successor warrant
agent shall promptly cause notice of its succession as warrant agent to be
mailed (by first class mail, postage prepaid) to the Holder at the Holder's last
address as shown on the Warrant Register.

        15. Miscellaneous.

        (a)  This Warrant shall be binding on and inure to the benefit of the
parties hereto and their respective successors and assigns. Subject to the
preceding sentence, nothing in this Warrant shall be construed to give to any
Person other than the Company and the Holder any legal or equitable right,
remedy or cause of action under this Warrant. This Warrant may be amended only
in writing signed by the Company and the Holder and their successors and
assigns.

        (b)  All questions concerning the construction, validity, enforcement
and interpretation of this Warrant shall be governed by and construed and
enforced in accordance with the internal laws of the State of New York, without
regard to the principles of conflicts of law thereof. Each party agrees that all
legal proceedings concerning the interpretations, enforcement and defense of the
transactions contemplated by this Warrant (whether brought against a party
hereto or its respective affiliates, directors, officers, shareholders,
employees or agents) shall be commenced in the state and federal courts sitting
in the City of New York, Borough of Manhattan. Each party hereto hereby
irrevocably submits to the exclusive jurisdiction of the state and federal
courts sitting in the City of New York, Borough of Manhattan for the
adjudication of any dispute hereunder or in connection herewith or with any
transaction contemplated hereby or discussed herein (including with respect to
the enforcement of this Warrant), and hereby irrevocably waives, and agrees not
to assert in any suit, action or proceeding, any claim that it is not personally
subject to the jurisdiction of any such court, that such suit, action or
proceeding is improper. Each party hereto hereby irrevocably waives personal
service of process and consents to process being served in any such suit, action
or proceeding by mailing a copy thereof via registered or certified mail or
overnight delivery (with evidence of delivery) to such party at the address in
effect for notices to it under this Warrant and agrees that such service shall
constitute good and sufficient service of process and notice thereof. Nothing
contained herein shall be deemed to limit in any way any right to serve process
in any manner permitted by law. Each party hereto (including its affiliates,
agents, officers, directors and employees) hereby irrevocably waives, to the
fullest extent permitted by applicable law, any and all right to trial by jury
in any legal proceeding arising out of or relating to this Warrant or the
transactions contemplated hereby. If either party shall commence an action or
proceeding to enforce any provisions of this Warrant, then the prevailing party
in such action or proceeding shall be reimbursed by the other party for its
reasonable attorneys fees and other costs and expenses incurred with the
investigation, preparation and prosecution of such action or proceeding.

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        (c)  The headings herein are for convenience only, do not constitute a
part of this Warrant and shall not be deemed to limit or affect any of the
provisions hereof.

        (d)  In case any one or more of the provisions of this Warrant shall be
invalid or unenforceable in any respect, the validity and enforceability of the
remaining terms and provisions of this Warrant shall not in any way be affected
or impaired thereby and the parties will attempt in good faith to agree upon a
valid and enforceable provision which shall be a commercially reasonable
substitute therefor, and upon so agreeing, shall incorporate such substitute
provision in this Warrant.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK,
SIGNATURE PAGE FOLLOWS]

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        IN WITNESS WHEREOF, the Company has caused this Warrant to be duly
executed by its authorized officer as of the date first indicated above.

    AVI BIOPHARMA, INC.
 
 
By:
 
/s/  DENIS R. BURGER, PH.D.      

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    Name: Denis R. Burger, Ph.D.
Title: Chairman & Chief Financial Officer

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Exhibit A

FORM OF ELECTION TO PURCHASE

To AVI BioPharma, Inc.:

        In accordance with Warrant No. [    ] issued to the undersigned, the
undersigned hereby elects to purchase                        shares of common
stock ("Common Stock"), [$    ] par value per share, of AVI BioPharma, Inc.

        1. Form of Warrant Exercise Price. The Holder intends that payment of
the Exercise Price shall be made as:

    "Cash Exercise" with respect to    

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    Warrant Shares; and/or         "Cashless Exercise" with respect to    

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    Warrant Shares (to the extent permitted by the terms of the Warrant).

        2. Payment of Exercise Price. In the event that the holder has elected a
Cash Exercise with respect to some or all of the Warrant Shares to be issued
pursuant hereto, the holder shall pay the sum of $                        to the
Company in accordance with the terms of the Warrant.

        By its delivery of this Form of Election To Purchase, the Holder
represents and warrants to the Company that in giving effect to the exercise
evidenced hereby the Holder will not beneficially own in excess of the number of
shares of Common Stock (determined in accordance with Section 13(d) of the
Securities Exchange Act of 1934) permitted to be owned under Section 11of this
Warrant to which this notice relates.

        The undersigned requests that certificates for the shares of Common
Stock issuable upon this exercise be issued in the name of

PLEASE INSERT SOCIAL SECURITY
OR TAX IDENTIFICATION NUMBER:  

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Please print name and address
 
 
 
 

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Exhibit B

Warrant Shares Exercise Log

Date

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Number of Warrant Shares
Available to be Exercised

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Number of Warrant Shares
Exercised

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Number of Warrant Shares
Remaining to be Exercised

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Exhibit C

FORM OF ASSIGNMENT

[To be completed and signed only upon transfer of Warrant]

        FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto                        the right represented by the within Warrant to
purchase                        shares of Common Stock of AVI BioPharma, Inc. to
which the within Warrant relates and appoints                        attorney to
transfer said right on the books of AVI BioPharma, Inc. with full power of
substitution in the premises.

Dated:                   ,                   
 
 

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(Signature must conform in all respects to name of holder as specified on the
face of the Warrant)      
 
 

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Address of Transferee          

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  In the presence of:    

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QuickLinks

AVI BIOPHARMA, INC. WARRANT
Exhibit A FORM OF ELECTION TO PURCHASE
Exhibit B Warrant Shares Exercise Log
Exhibit C FORM OF ASSIGNMENT