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REGISTRATION RIGHTS AGREEMENT

        This Registration Rights Agreement (this "Agreement") is made and
entered into as of March 25, 2002, by and among AVI BioPharma, Inc. an Oregon
corporation (the "Company"), and each of the purchasers identified on the
signature pages hereto (each a "Purchaser" and collectively, the "Purchasers").

        This Agreement is made pursuant to the Securities Purchase Agreement,
dated as of the date hereof among the Company and the Purchasers (the "Purchase
Agreement").

        The Company and the Purchasers hereby agree as follows:

        1. Definitions. Capitalized terms used and not otherwise defined herein
that are defined in the Purchase Agreement shall have the meanings given such
terms in the Purchase Agreement. As used in this Agreement, the following terms
shall have the following meanings:

        "Effectiveness Date" means the earlier of (a) the 120th day following
the Closing Date and (b) the fifth Trading Day following the date on which the
Company is notified by the Commission that such Registration Statement will not
be reviewed or is no longer subject to further review and comments.

        "Effectiveness Period" shall have the meaning set forth in Section 2(a).

        "Filing Date" means, with respect to the initial Registration Statement
required to be filed hereunder, the 30th day following the Closing Date.

        "Holder" or "Holders" means the holder or holders, as the case may be,
from time to time of Registrable Securities.

        "Indemnified Party" shall have the meaning set forth in Section 5(c).

        "Indemnifying Party" shall have the meaning set forth in Section 5(c).

        "Losses" shall have the meaning set forth in Section 5(a).

        "Proceeding" means an action, claim, suit, investigation or proceeding
(including, without limitation, an investigation or partial proceeding, such as
a deposition), whether commenced or threatened.

        "Prospectus" means the prospectus included in a Registration Statement
(including, without limitation, a prospectus that includes any information
previously omitted from a prospectus filed as part of an effective registration
statement in reliance upon Rule 430A promulgated under the Securities Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Registrable Securities covered by the
Registration Statement, and all other amendments and supplements to the
Prospectus, including post-effective amendments, and all material incorporated
by reference or deemed to be incorporated by reference in such Prospectus.

        "Registrable Securities" means the shares of Common Stock issued
pursuant to the Purchase Agreement and issuable upon exercise of the Warrants.

        "Registration Statement" means the initial registration statement
required to be filed hereunder and any additional registration statements
contemplated by Section 2(d), including (in each case) the Prospectus,
amendments and supplements to such registration statement or Prospectus,
including pre- and post-effective amendments, all exhibits thereto, and all
material incorporated by reference or deemed to be incorporated by reference in
such registration statement.

        "Rule 144" means Rule 144 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

        "Rule 415" means Rule 415 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

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        "Rule 424" means Rule 424 promulgated by the Commission pursuant to the
Securities Act, as such Rule may be amended from time to time, or any similar
rule or regulation hereafter adopted by the Commission having substantially the
same effect as such Rule.

        "Warrants" means the Common Stock purchase warrants issued pursuant to
the Purchase Agreement.

        2. Registration.

        (a)  On or prior to the Filing Date, the Company shall prepare and file
with the Commission a Registration Statement covering the Registrable Securities
for an offering to be made on a continuous basis pursuant to Rule 415. The
Registration Statement shall be on Form S-3 (except if the Company is not then
eligible to register for resale the Registrable Securities on Form S-3, in which
case such registration shall be on another appropriate form in accordance
herewith) and shall contain (except if otherwise required by the Commission) the
"Plan of Distribution" attached hereto as Annex A. The Company shall cause the
Registration Statement to become effective and remain effective as provided
herein. The Company shall use its best efforts to cause the Registration
Statement to be declared effective under the Securities Act as promptly as
possible after the filing thereof, but in any event prior to its Effectiveness
Date, and shall use its best efforts to keep the Registration Statement
continuously effective under the Securities Act until the date which is the
earlier date of when (i) all Registrable Securities have been sold or (ii) all
Registrable Securities may be sold immediately without registration under the
Securities Act and without volume restrictions pursuant to Rule 144(k), as
determined by the counsel to the Company pursuant to an unqualified written
opinion letter to such effect, addressed and acceptable to the Company's
transfer agent and the affected Holders (the "Effectiveness Period").

        (b)  If: (a) any Registration Statement is not filed on or prior to the
Filing Date; (b) a Registration Statement filed hereunder is not declared
effective by the Commission by the Effectiveness Date; (c) after a Registration
Statement is filed with and declared effective by the Commission, such
Registration Statement ceases to be effective (by suspension or otherwise) as to
all Registrable Securities to which it is required to relate at any time prior
to the expiration of the Effectiveness Period without being succeeded within
fifteen (15) Trading Days by an amendment to such Registration Statement or by a
subsequent Registration Statement filed with and declared effective by the
Commission; (d) the Common Stock is not listed or quoted, or is suspended from
trading on the Nasdaq National Market for a period of three (3) Trading Days
(which need not be consecutive Trading Days); or (e) the exercise rights of the
Holders pursuant to the Warrants are suspended for any reason (any such failure
or breach being referred to as an "Event," and for purposes of clause (a),
(b) or (e) the date on which such Event occurs, or for purposes of clause (c)
the date which such fifteen (15) Trading Day-period is exceeded, or for purposes
of clause (d) the date on which such three (3) Trading Day period is exceeded,
being referred to as "Event Date"), then until the applicable Event is cured,
the Company shall pay to each Holder an amount in cash, as liquidated damages
and not as a penalty, equal to 1.0% for each thirty (30) day period (prorated
for partial periods) on a daily basis of the aggregate purchase price paid by
such Holder pursuant to the Purchase Agreement. Such liquidation damages shall
be paid not less than each thirty (30) days during an Event and within three
(3) days following the date on which such Event has been cured by the Company.
If the Company fails to pay any liquidated damages pursuant to this Section in
full within seven days after the date payable, the Company will pay interest
thereon at a rate of 18% per annum (or such lesser maximum amount that is
permitted to be paid by applicable law) to the Holder, accruing daily from the
date such liquidated damages are due until such amounts, plus all such interest
thereon, are paid in full.

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        3. Registration Procedures

        In connection with the Company's registration obligations hereunder, the
Company shall:

        (a)  Not less than three (3) Trading Days prior to the filing of the
Registration Statement or any related Prospectus or any amendment or supplement
thereto, the Company shall, (i) furnish to the Holders copies of all such
documents proposed to be filed (including documents incorporated or deemed
incorporated by reference) which documents will be subject to the review of such
Holders, and (ii) cause its officers and directors, counsel and independent
certified public accountants to respond to such inquiries as shall be necessary,
in the reasonable opinion of respective counsel to conduct a reasonable
investigation within the meaning of the Securities Act. The Company shall not
file the Registration Statement or any such Prospectus or any amendments or
supplements thereto to which the Holders of a majority of the Registrable
Securities shall reasonably object in good faith.

        (b)  (i) Prepare and file with the Commission such amendments, including
post-effective amendments, to the Registration Statement and the Prospectus used
in connection therewith as may be necessary to keep the Registration Statement
continuously effective as to the applicable Registrable Securities for the
Effectiveness Period and prepare and file with the Commission such additional
Registration Statements in order to register for resale under the Securities Act
all of the Registrable Securities; (ii) cause the related Prospectus to be
amended or supplemented by any required Prospectus supplement, and as so
supplemented or amended to be filed pursuant to Rule 424; (iii) respond as
promptly as reasonably possible, and in any event within ten (10) days, to any
comments received from the Commission with respect to the Registration Statement
or any amendment thereto and, as promptly as reasonably possible provide the
Holders true and complete copies of all correspondence from and to the
Commission relating to the Registration Statement; and (iv) comply in all
material respects with the provisions of the Securities Act and the Exchange Act
with respect to the disposition of all Registrable Securities covered by the
Registration Statement during the applicable period in accordance with the
intended methods of disposition by the Holders thereof set forth in the
Registration Statement as so amended or in such Prospectus as so supplemented.

        (c)  Notify the Holders of Registrable Securities to be sold as promptly
as reasonably possible (and, in the case of (i)(A) below, not less than three
(3) Trading Days prior to such filing) and (if requested by any such Person)
confirm such notice in writing no later than one (1) Trading Day following the
day (i)(A) when a Prospectus or any Prospectus supplement or post-effective
amendment to the Registration Statement is proposed to be filed; (B) when the
Commission notifies the Company whether there will be a "review" of such
Registration Statement and whenever the Commission comments in writing on such
Registration Statement (the Company shall provide true and complete copies
thereof and all written responses thereto to each of the Holders); and (C) with
respect to the Registration Statement or any post-effective amendment, when the
same has become effective; (ii) of any request by the Commission or any other
Federal or state governmental authority for amendments or supplements to the
Registration Statement or Prospectus or for additional information; (iii) of the
issuance by the Commission of any stop order suspending the effectiveness of the
Registration Statement covering any or all of the Registrable Securities or the
initiation of any Proceedings for that purpose; (iv) of the receipt by the
Company of any notification with respect to the suspension of the qualification
or exemption from qualification of any of the Registrable Securities for sale in
any jurisdiction, or the initiation or threatening of any Proceeding for such
purpose; and (v) of the occurrence of any event or passage of time that makes
the financial statements included in the Registration Statement ineligible for
inclusion therein or any statement made in the Registration Statement or
Prospectus or any document incorporated or deemed to be incorporated therein by
reference untrue in any material respect or that requires any revisions to the
Registration Statement, Prospectus or other documents

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so that, in the case of the Registration Statement or the Prospectus, as the
case may be, it will 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.

        (d)  Use its best efforts to avoid the issuance of, or, if issued,
obtain the withdrawal of (i) any order suspending the effectiveness of the
Registration Statement, or (ii) any suspension of the qualification (or
exemption from qualification) of any of the Registrable Securities for sale in
any jurisdiction, at the earliest practicable moment.

        (e)  Furnish to each Holder, without charge, at least one conformed copy
of the Registration Statement and each amendment thereto, including financial
statements and schedules, all documents incorporated or deemed to be
incorporated therein by reference, and all exhibits to the extent requested by
such Person (including those previously furnished or incorporated by reference)
promptly after the filing of such documents with the Commission.

        (f)    Promptly deliver to each Holder, without charge, as many copies
of the Prospectus or Prospectuses (including each form of prospectus) and each
amendment or supplement thereto as such Persons may reasonably request. The
Company hereby consents to the use of such Prospectus and each amendment or
supplement thereto by each of the selling Holders in connection with the
offering and sale of the Registrable Securities covered by such Prospectus and
any amendment or supplement thereto.

        (g)  Use its best efforts to register or qualify or cooperate with the
selling Holders in connection with the registration or qualification (or
exemption from such registration or qualification) of all applicable Registrable
Securities for offer and sale under the securities or Blue Sky laws of all
applicable jurisdictions within the United States as any Holder requests in
writing, to keep each such registration or qualification (or exemption
therefrom) effective during the Effectiveness Period and to do any and all other
acts or things necessary or advisable to enable the disposition in such
jurisdictions of the Registrable Securities covered by a Registration Statement;
provided, that the Company shall not be required to qualify generally to do
business in any jurisdiction where it is not then so qualified or subject the
Company to any material tax in any such jurisdiction where it is not then so
subject.

        (h)  Cooperate with the Holders to facilitate the timely preparation and
delivery of certificates representing Registrable Securities to be delivered to
a transferee pursuant to a Registration Statement, which certificates shall be
free, to the extent permitted by the Purchase Agreement, of all restrictive
legends, and to enable such Registrable Securities to be in such denominations
and registered in such names as any such Holders may request.

        (i)    Upon the occurrence of any event contemplated by Section 3(c)(v),
as promptly as reasonably possible, prepare a supplement or amendment, including
a post-effective amendment, to the Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither the Registration Statement nor such Prospectus
will contain an untrue statement of a material fact or omit to state a 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.

        (j)    Comply with all applicable rules and regulations of the
Commission.

        (k)  The Company may require each selling Holder to furnish to the
Company a certified statement as to the number of shares of Common Stock
beneficially owned by such Holder and such other reasonable information as the
Company is required to obtain for inclusion in the Registration Statement.

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        4. Registration Expenses. All fees and expenses incident to the
performance of or compliance with this Agreement by the Company shall be borne
by the Company whether or not any Registrable Securities are sold pursuant to
the Registration Statement. The fees and expenses referred to in the foregoing
sentence shall include, without limitation, (i) all registration and filing fees
(including, without limitation, fees and expenses (A) with respect to filings
required to be made with the Trading Market on which the Common Stock is then
listed for trading, and (B) in compliance with applicable state securities or
Blue Sky laws), (ii) printing expenses (including, without limitation, expenses
of printing certificates for Registrable Securities and of printing
prospectuses, (iii) messenger, telephone and delivery expenses, (iv) Securities
Act liability insurance, if the Company so desires such insurance, and (v) fees
and expenses of all other Persons retained by the Company in connection with the
consummation of the transactions contemplated by this Agreement. In addition,
the Company shall be responsible for all of its internal expenses incurred in
connection with the consummation of the transactions contemplated by this
Agreement (including, without limitation, all salaries and expenses of its
officers and employees performing legal or accounting duties), the expense of
any annual audit and the fees and expenses incurred in connection with the
listing of the Registrable Securities on any securities exchange as required
hereunder.

        5. Indemnification

        (a)  Indemnification by the Company. The Company shall, notwithstanding
any termination of this Agreement, indemnify and hold harmless each Holder, the
officers, directors, agents, brokers (including brokers who offer and sell
Registrable Securities as principal as a result of a pledge or any failure to
perform under a margin call of Common Stock), investment advisors and employees
of each of them, each Person who controls any such Holder (within the meaning of
Section 15 of the Securities Act or Section 20 of the Exchange Act) and the
officers, directors, agents and employees of each such controlling Person, to
the fullest extent permitted by applicable law, from and against any and all
losses, claims, damages, liabilities, costs (including, without limitation,
reasonable costs of preparation and reasonable attorneys' fees) and expenses
(collectively, "Losses"), as incurred, arising out of or relating to any untrue
or alleged untrue statement of a material fact contained in the Registration
Statement, any Prospectus or any form of prospectus or in any amendment or
supplement thereto or in any preliminary prospectus, or arising out of or
relating to any omission or alleged omission of a material fact required to be
stated therein or necessary to make the statements therein (in the case of any
Prospectus or form of prospectus or supplement thereto, in the light of the
circumstances under which they were made) not misleading, except to the extent,
but only to the extent, that (1) such untrue statements or omissions are based
solely upon information regarding such Holder furnished in writing to the
Company by such Holder expressly for use therein, or to the extent that such
information relates to such Holder or such Holder's proposed method of
distribution of Registrable Securities and was reviewed and expressly approved
in writing by such Holder expressly for use in the Registration Statement, such
Prospectus or such form of Prospectus or in any amendment or supplement thereto
(it being understood that the Holder has approved Annex A hereto for this
purpose) or (2) in the case of an occurrence of an event of the type specified
in Section 3(c)(ii)-(v), the use by such Holder of an outdated or defective
Prospectus after the Company has notified such Holder in writing that the
Prospectus is outdated or defective and prior to the receipt by such Holder of
the Advice contemplated in Section 6(d). The Company shall notify the Holders
promptly of the institution, threat or assertion of any Proceeding of which the
Company is aware in connection with the transactions contemplated by this
Agreement.

        (b)  Indemnification by Holders. Each Holder shall, severally and not
jointly, indemnify and hold harmless the Company, its directors, officers,
agents and employees, each Person who controls the Company (within the meaning
of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the
directors, officers, agents or employees of such controlling Persons, to the

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fullest extent permitted by applicable law, from and against all Losses, as
incurred, arising solely out of or based solely upon: (x) such Holder's failure
to comply with the prospectus delivery requirements of the Securities Act or
(y) any untrue statement of a material fact contained in the Registration
Statement, any Prospectus, or any form of prospectus, or in any amendment or
supplement thereto, or arising solely out of or based solely upon any omission
of a material fact required to be stated therein or necessary to make the
statements therein not misleading to the extent, but only to the extent, that
such untrue statement or omission is contained in any information so furnished
in writing by such Holder to the Company specifically for inclusion in such
Registration Statement or such Prospectus or to the extent that (1) such untrue
statements or omissions are based solely upon information regarding such Holder
furnished in writing to the Company by such Holder expressly for use therein, or
to the extent that such information relates to such Holder or such Holder's
proposed method of distribution of Registrable Securities and was reviewed and
expressly approved in writing by such Holder expressly for use in the
Registration Statement (it being understood that the Holder has approved Annex A
hereto for this purpose), such Prospectus or such form of Prospectus or in any
amendment or supplement thereto or (2) in the case of an occurrence of an event
of the type specified in Section 3(c)(ii)-(v), the use by such Holder of an
outdated or defective Prospectus after the Company has notified such Holder in
writing that the Prospectus is outdated or defective and prior to the receipt by
such Holder of the Advice contemplated in Section 6(d). In no event shall the
liability of any selling Holder hereunder be greater in amount than the dollar
amount of the net proceeds received by such Holder upon the sale of the
Registrable Securities giving rise to such indemnification obligation.

        (c)  Conduct of Indemnification Proceedings. If any Proceeding shall be
brought or asserted against any Person entitled to indemnity hereunder (an
"Indemnified Party"), such Indemnified Party shall promptly notify the Person
from whom indemnity is sought (the "Indemnifying Party") in writing, and the
Indemnifying Party shall assume the defense thereof, including the employment of
counsel reasonably satisfactory to the Indemnified Party and the payment of all
fees and expenses incurred in connection with defense thereof; provided, that
the failure of any Indemnified Party to give such notice shall not relieve the
Indemnifying Party of its obligations or liabilities pursuant to this Agreement,
except (and only) to the extent that it shall be finally determined by a court
of competent jurisdiction (which determination is not subject to appeal or
further review) that such failure shall have proximately and materially
adversely prejudiced the Indemnifying Party.

        An Indemnified Party shall have the right to employ separate counsel in
any such Proceeding and to participate in the defense thereof, but the fees and
expenses of such counsel shall be at the expense of such Indemnified Party or
Parties unless: (1) the Indemnifying Party has agreed in writing to pay such
fees and expenses; (2) the Indemnifying Party shall have failed promptly to
assume the defense of such Proceeding and to employ counsel reasonably
satisfactory to such Indemnified Party in any such Proceeding; or (3) the named
parties to any such Proceeding (including any impleaded parties) include both
such Indemnified Party and the Indemnifying Party, and such Indemnified Party
shall have been advised by counsel that a conflict of interest is likely to
exist if the same counsel were to represent such Indemnified Party and the
Indemnifying Party (in which case, if such Indemnified Party notifies the
Indemnifying Party in writing that it elects to employ separate counsel at the
expense of the Indemnifying Party, the Indemnifying Party shall not have the
right to assume the defense thereof and such counsel shall be at the expense of
the Indemnifying Party). The Indemnifying Party shall not be liable for any
settlement of any such Proceeding effected without its written consent, which
consent shall not be unreasonably withheld. No Indemnifying Party shall, without
the prior written consent of the Indemnified Party, effect any settlement of any
pending Proceeding in respect of which any Indemnified Party is a party, unless
such settlement includes an unconditional release of such Indemnified Party from
all liability on claims that are the subject matter of such Proceeding.

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        All fees and expenses of the Indemnified Party (including reasonable
fees and expenses to the extent incurred in connection with investigating or
preparing to defend such Proceeding in a manner not inconsistent with this
Section) shall be paid to the Indemnified Party, as incurred, within ten
(10) Trading Days of written notice thereof to the Indemnifying Party
(regardless of whether it is ultimately determined that an Indemnified Party is
not entitled to indemnification hereunder; provided, that the Indemnifying Party
may require such Indemnified Party to undertake to reimburse all such fees and
expenses to the extent it is finally judicially determined that such Indemnified
Party is not entitled to indemnification hereunder).

        (d)  Contribution. If a claim for indemnification under Section 5(a) or
5(b) is unavailable to an Indemnified Party (by reason of public policy or
otherwise), then each Indemnifying Party, in lieu of indemnifying such
Indemnified Party, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such Losses, in such proportion as is
appropriate to reflect the relative fault of the Indemnifying Party and
Indemnified Party in connection with the actions, statements or omissions that
resulted in such Losses as well as any other relevant equitable considerations.
The relative fault of such Indemnifying Party and Indemnified Party shall be
determined by reference to, among other things, whether any action in question,
including any untrue or alleged untrue statement of a material fact or omission
or alleged omission of a material fact, has been taken or made by, or relates to
information supplied by, such Indemnifying Party or Indemnified Party, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such action, statement or omission. The amount paid or
payable by a party as a result of any Losses shall be deemed to include, subject
to the limitations set forth in Section 5(c), any reasonable attorneys' or other
reasonable fees or expenses incurred by such party in connection with any
Proceeding to the extent such party would have been indemnified for such fees or
expenses if the indemnification provided for in this Section was available to
such party in accordance with its terms.

        The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 5(d) were determined by pro rata
allocation or by any other method of allocation that does not take into account
the equitable considerations referred to in the immediately preceding paragraph.
Notwithstanding the provisions of this Section 5(d), no Holder shall be required
to contribute, in the aggregate, any amount in excess of the amount by which the
proceeds actually received by such Holder from the sale of the Registrable
Securities subject to the Proceeding exceeds the amount of any damages that such
Holder has otherwise been required to pay by reason of such untrue or alleged
untrue statement or omission or alleged omission. No Person guilty of fraudulent
misrepresentation (within the meaning of Section 11(f) of the Securities Act)
shall be entitled to contribution from any Person who was not guilty of such
fraudulent misrepresentation.

        The indemnity and contribution agreements contained in this Section are
in addition to any liability that the Indemnifying Parties may have to the
Indemnified Parties.

        6. Miscellaneous

        (a)  Remedies. In the event of a breach by the Company or by a Holder,
of any of their obligations under this Agreement, each Holder or the Company, as
the case may be, in addition to being entitled to exercise all rights granted by
law and under this Agreement, including recovery of damages, will be entitled to
specific performance of its rights under this Agreement. The Company and each
Holder agree that monetary damages would not provide adequate compensation for
any losses incurred by reason of a breach by it of any of the provisions of this
Agreement and hereby further agrees that, in the event of any action for
specific performance in respect of such breach, it shall waive the defense that
a remedy at law would be adequate.

        (b)  No Piggyback on Registrations. Except as and to the extent
specified in Schedule 6(b) hereto, neither the Company nor any of its security
holders (other than the Holders in such

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capacity pursuant hereto) may include securities of the Company in the
Registration Statement other than the Registrable Securities, and the Company
shall not after the date hereof enter into any agreement providing any such
right for inclusion of shares in the Registration Statement to any of its
security holders. Except as and to the extent specified in Schedule 6(b) hereto,
the Company has not previously entered into any agreement granting any
registration rights with respect to any of its securities to any Person which
has not been fully satisfied.

        (c)  Compliance. Each Holder covenants and agrees that it will comply
with the prospectus delivery requirements of the Securities Act as applicable to
it in connection with sales of Registrable Securities pursuant to the
Registration Statement.

        (d)  Discontinued Disposition. Each Holder agrees by its acquisition of
such Registrable Securities that, upon receipt of a notice from the Company of
the occurrence of any event of the kind described in Section 3(c), such Holder
will forthwith discontinue disposition of such Registrable Securities under the
Registration Statement until such Holder's receipt of the copies of the
supplemented Prospectus and/or amended Registration Statement or until it is
advised in writing (the "Advice") by the Company that the use of the applicable
Prospectus may be resumed, and, in either case, has received copies of any
additional or supplemental filings that are incorporated or deemed to be
incorporated by reference in such Prospectus or Registration Statement. The
Company may provide appropriate stop orders to enforce the provisions of this
paragraph.

        (e)  Piggy-Back Registrations. If at any time during the Effectiveness
Period there is not an effective Registration Statement covering all of the
Registrable Securities and the Company shall determine to prepare and file with
the Commission a registration statement relating to an offering for its own
account or the account of others under the Securities Act of any of its equity
securities, other than on Form S-4 or Form S-8 (each as promulgated under the
Securities Act) or their then equivalents relating to equity securities to be
issued solely in connection with any acquisition of any entity or business or
equity securities issuable in connection with stock option or other employee
benefit plans, then the Company shall send to each Holder written notice of such
determination and, if within fifteen days after receipt of such notice, any such
Holder shall so request in writing, the Company shall include in such
registration statement all or any part of such Registrable Securities such
holder requests to be registered, subject to customary underwriter cutbacks
applicable to all holders of registration rights.

        (f)    Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the same shall be in writing and signed by the Company
and the Holders of the then outstanding Registrable Securities. Notwithstanding
the foregoing, a waiver or consent to depart from the provisions hereof with
respect to a matter that relates exclusively to the rights of certain Holders
and that does not directly or indirectly affect the rights of other Holders may
be given by Holders of at least a majority of the Registrable Securities to
which such waiver or consent relates; provided, however, that the provisions of
this sentence may not be amended, modified, or supplemented except in accordance
with the provisions of the immediately preceding sentence.

        (g)  Notices. Any and all notices or other communications or deliveries
required or permitted to be provided hereunder 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
telephone number specified in this Section prior to 6:30 p.m. (New York City
time) on a Trading Day, (ii) the Trading Day after the date of transmission, if
such notice or communication is delivered via facsimile at the facsimile
telephone number specified in this Agreement later than 6:30 p.m. (New York City
time) on any date and earlier than 11:59 p.m.

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(New York City time) on such date, (iii) the Trading 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 address for such notices and communications shall be as follows:

If to the Company:   AVI BioPharma, Inc.
One S.W. Columbia, Suite 1105
Portland, Oregon 97258
Facsimile: (503) 227-0751
If to a Purchaser:
 
To the address set forth under such Purchaser name
on the signature pages hereto.
If to any other Person who is then the registered Holder:
 
 
To the address of such Holder as it appears in the
stock transfer books of the Company

or such other address as may be designated in writing hereafter, in the same
manner, by such Person.

        (h)  Successors and Assigns. This Agreement shall inure to the benefit
of and be binding upon the successors and permitted assigns of each of the
parties and shall inure to the benefit of each Holder. The Company may not
assign its rights or obligations hereunder without the prior written consent of
each Holder. Each Holder may assign their respective rights hereunder in the
manner and to the Persons as permitted under the Purchase Agreement.

        (i)    Execution and Counterparts. This Agreement may be executed in any
number of counterparts, each of which when so executed shall be deemed to be an
original and, all of which taken together shall constitute one and the same
Agreement. In the event that any signature is delivered by facsimile
transmission, such signature shall create a valid binding obligation of the
party executing (or on whose behalf such signature is executed) the same with
the same force and effect as if such facsimile signature were the original
thereof.

        (j)    Governing Law. All questions concerning the construction,
validity, enforcement and interpretation of this Agreement 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 Proceedings concerning the interpretations, enforcement
and defense of the transactions contemplated by this Agreement and any other
Transaction Documents (whether brought against a party hereto or its respective
affiliates, directors, officers, shareholders, employees or agents) shall be
commenced exclusively 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 the any of the Transaction
Documents), and hereby irrevocably waives, and agrees not to assert in any
Proceeding, any claim that it is not personally subject to the jurisdiction of
any such court, that such Proceeding is improper. Each party hereto hereby
irrevocably waives personal service of process and consents to process being
served in any such 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 Agreement 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 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 Agreement or the

9

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transactions contemplated hereby. If either party shall commence a Proceeding to
enforce any provisions of a Transaction Document, then the prevailing party in
such 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 Proceeding.

        (k)  Cumulative Remedies. The remedies provided herein are cumulative
and not exclusive of any remedies provided by law.

        (l)    Severability. If any term, provision, covenant or restriction of
this Agreement is held by a court of competent jurisdiction to be invalid,
illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their reasonable efforts to find and employ an alternative
means to achieve the same or substantially the same result as that contemplated
by such term, provision, covenant or restriction. It is hereby stipulated and
declared to be the intention of the parties that they would have executed the
remaining terms, provisions, covenants and restrictions without including any of
such that may be hereafter declared invalid, illegal, void or unenforceable.

        (m)  Headings. The headings in this Agreement are for convenience of
reference only and shall not limit or otherwise affect the meaning hereof.

        (n)  Independent Nature of Purchasers' Obligations and Rights. The
obligations of each Purchaser hereunder are several and not joint with the
obligations of any other Purchaser hereunder, and no Purchaser shall be
responsible in any way for the performance of the obligations of any other
Purchaser hereunder. Nothing contained herein or in any other agreement or
document delivered at any closing, and no action taken by any Purchaser pursuant
hereto or thereto, shall be deemed to constitute the Purchasers as a
partnership, an association, a joint venture or any other kind of entity, or
create a presumption that the Purchasers are in any way acting in concert with
respect to such obligations or the transactions contemplated by this Agreement.
Each Purchaser shall be entitled to protect and enforce its rights, including
without limitation the rights arising out of this Agreement, and it shall not be
necessary for any other Purchaser to be joined as an additional party in any
proceeding for such purpose.

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
SIGNATURE PAGES TO FOLLOW]

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

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

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

[REMAINDER OF PAGE INTENTIONALLY LEFT BLANK
SIGNATURE PAGES OF PURCHASERS TO FOLLOW]

11

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

    SMITHFIELD FIDUCIARY LLC
 
 
By:
 
/s/  ADAM J. CHILL      

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    Name: Adam J. Chill
Title: Authorized Signatory
 
 
Address for Notice:
 
 
c/o Highbridge Capital Management, LLC
9 West 57th Street, 27th Floor
New York, NY 10019
Fax: 212-751-0755
Tel: 212-287-4720
Attention: Ari J. Storch / Adam J. Chill

12

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SF CAPITAL PARTNERS LTD

 

 

By:

 

/s/  BRIAN H. DAVIDSON      

--------------------------------------------------------------------------------

 
 
Name: Brian H. Davidson
Title: Authorized Signatory
 
 
Address for Notice:
 
 
SF Capital Partners Ltd.
Attention: Brian H. Davidson
1500 West Market Street, Suite 200
Mequon, Wisconsin 53092
 
 
Phone: (262) 241-1810
Facsimile: (262) 241-1888

13

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    CASTLE CREEK HEALTHCARE
PARTNERS LLC
 
 
By:
 
CASTLE CREEK PARTNERS,
LLC, its Investment Manager
 
 
By:
 
/s/  THOMAS A. FREI      

--------------------------------------------------------------------------------

    Name: Thomas A. Frei
Title: Managing Member
 
 
Address for Notice:
 
 
Castle Creek Healthcare Partners, LLC
c/o Castle Creek Partners, LLC
111 West Jackson Blvd, Suite 2020
Chicago, IL 60604

14

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    CC LIFE SCIENCE, LTD.
 
 
By:
 
/s/  THOMAS A. FREI      

--------------------------------------------------------------------------------

    Name: Thomas A. Frei
Title: Member
 
 
Address for Notice:
 
 
CC Life Science, Ltd.
c/o Castle Creek Life Science Partners, LLC
111 West Jackson Blvd, Suite 2020
Chicago, IL 60604

15

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    SDS MERCHANT FUND, LP
 
 
By:
 
/s/  STEVE DERBY      

--------------------------------------------------------------------------------

    Name: Steve Derby
Title: Managing Member
 
 
Address for Notice:
 
 
SDS Merchant Fund, LP
c/o SDS Capital Partners, LLC
1 Sound Shore Drive, Suite 202
Greenwich, CT 06830

16

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    DMG LEGACY FUND LLC
 
 
By:
 
/s/  ANDREW WILDER      

--------------------------------------------------------------------------------

    Name: Andrew Wilder
Title: Chief Financial Officer
 
 
Address for Notice:
 
 
DMG Legacy Fund LLC
c/o DMG Advisors LLC
One Sound Shore Drive, Ste 202
Greenwich, CT 06830

17

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    DMG LEGACY INSTITUTIONAL FUND LLC
 
 
By:
 
/s/  ANDREW WILDER      

--------------------------------------------------------------------------------

    Name: Andrew Wilder
Title: Chief Financial Officer
 
 
Address for Notice:
 
 
DMG Legacy Institutional Fund LLC
c/o DMG Advisors LLC
One Sound Shore Drive, Ste 202
Greenwich, CT 06830

18

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    DMG LEGACY INTERNATIONAL LTD.
 
 
By:
 
/s/  ANDREW WILDER      

--------------------------------------------------------------------------------

    Name: Andrew Wilder
Title: Chief Financial Officer
 
 
Address for Notice:
 
 
DMG Legacy International Ltd.
c/o DMG Advisors LLC
One Sound Shore Drive, Ste 202
Greenwich, CT 06830

19

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    GRYPHON MASTER FUND, L.P.
 
 
By:
 
/s/  E.B. LYON, IV      

--------------------------------------------------------------------------------

    Name: E.B. Lyon, IV
Title: Authorized Agent
 
 
Address for Notice:
 
 
500 Crescent Court, Suite 270
Dallas, TX 75201

20

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QUANTICO PARTNERS, L.P.

 

 

By:

 

/s/  JEFFREY THORP      

--------------------------------------------------------------------------------

 
 
Name: Jeffrey Thorp
Title: Managing Partner of
Langley Capital, LLC,
its General Partner
 
 
Address for Notice:
 
 
Quantico Partners, L.P.
c/o Langley Capital, LLC
535 Madison Avenue, 7th Floor
New York, NY 10022
(212) 850-7528 Telephone
(212) 850-7589 Facsimile
JT@LangleyCapital.com

21

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    BNY CAPITAL MARKETS, INC.
 
 
By:
 
/s/  WESLEY V. PRITCHETT      

--------------------------------------------------------------------------------

    Name: Wesley V. Pritchett
Title: M.D.
 
 
Address for Notice:
 
 
Attn: Raymond Lang, Managing Director
BNY Capital Markets, Inc.
32 Old Slip, 15th Floor
New York, NY 10286

22

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    UNITED CAPITAL MANAGEMENT, INC.
 
 
By:
 
/s/  JAMES A. LUSTIG      

--------------------------------------------------------------------------------

    Name: James A. Lustig
Title: Proprietor
 
 
Address for Notice:
 
 
410 17th Street, Suite 1705
Denver, CO 80202

23

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    On behalf of
THE TAIL WIND FUND LIMITED
Tail Wind Advisory & Management Ltd.
 
 
By:
 
/s/  DAVID CROOK      

--------------------------------------------------------------------------------

    Name: David Crook
Title: Chief Executive Officer
 
 
Address for Notice:
 
 
David Crook, Esq.
Chief Executive Officer
Tail Wind Advisory & Management Ltd.
1st Floor, No. 1 Regent Street
London, SW1Y 4NS, UK
Tel: +44 20 7468 7691 Fax: 7657
 
 
Please copy all correspondence to:
Peter J. Weisman, P.C.
110 East 59th Street
New York, NY 10005
Tel: +212-418-4792 Fax: 212-317-8855
 
 
Please send the common shares a.s.a.p. directly to:
Bishop Rosen & Co.
Attn: Mr. D. Freedman
100 Broadway, 18th Floor
New York, NY 10006
Tel: +212-602-0054 Fax: +212-602-0697
 
 
Please send the warrants to:
The Tail Wind Fund, Ltd.
MecaPierson (Bahamas) Ltd.
Attn: Ngaire Rolle,
Windermere House, 404 East Bay St.,
PO Box SS 5539, Nassau, Bahamas
Tel: 242-393-8777 Fax: 242-393-9021

24

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    JULES NORDLICHT
 
 
By:
 
/s/  JULES NORDLICHT      

--------------------------------------------------------------------------------

    Name: Jules Nordlicht
Title:
 
 
Address for Notice:
 
 
255 W. Beech St
Long Beach, NY 11561

25

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Annex A

Plan of Distribution

        The selling stockholders and any of their pledgees, assignees and
successors-in-interest may, from time to time, sell any or all of their shares
of common stock on any stock exchange, market or trading facility on which the
shares are traded or in private transactions. These sales may be at fixed or
negotiated prices. The selling stockholders may use any one or more of the
following methods when selling shares:

•ordinary brokerage transactions and transactions in which the broker-dealer
solicits purchasers;

•block trades in which the broker-dealer will attempt to sell the shares as
agent but may position and resell a portion of the block as principal to
facilitate the transaction;

•purchases by a broker-dealer as principal and resale by the broker-dealer for
its account;

•an exchange distribution in accordance with the rules of the applicable
exchange;

•privately negotiated transactions;

•short sales

•broker-dealers may agree with the selling stockholders to sell a specified
number of such shares at a stipulated price per share;

•a combination of any such methods of sale; and

•any other method permitted pursuant to applicable law.

        The selling stockholders may also sell shares under Rule 144 under the
Securities Act, if available, rather than under this prospectus.

        Broker-dealers engaged by the selling stockholders may arrange for other
brokers-dealers to participate in sales. Broker-dealers may receive commissions
or discounts from the selling stockholders (or, if any broker-dealer acts as
agent for the purchaser of shares, from the purchaser) in amounts to be
negotiated. The selling stockholders do not expect these commissions and
discounts to exceed what is customary in the types of transactions involved.

        The selling stockholders may from time to time pledge or grant a
security interest in some or all of the shares of common stock or Warrants owned
by them and, if they default in the performance of their secured obligations,
the pledgees or secured parties may offer and sell the shares of common stock
from time to time under this prospectus, or under an amendment to this
prospectus under Rule 424(b)(3) or other applicable provision of the Securities
Act of 1933 amending the list of selling stockholders to include the pledgee,
transferee or other successors in interest as selling stockholders under this
prospectus.

        The selling stockholders also may transfer the shares of common stock in
other circumstances, in which case the transferees, pledgees or other successors
in interest will be the selling beneficial owners for purposes of this
prospectus.

        The selling stockholders and any broker-dealers or agents that are
involved in selling the shares may be deemed to be "underwriters" within the
meaning of the Securities Act in connection with such sales. In such event, any
commissions received by such broker-dealers or agents and any profit on the
resale of the shares purchased by them may be deemed to be underwriting
commissions or discounts under the Securities Act. The selling stockholders have
informed the Company that it does not have any agreement or understanding,
directly or indirectly, with any person to distribute the Common Stock.

        The Company is required to pay all fees and expenses incident to the
registration of the shares. The Company has agreed to indemnify the selling
stockholders against certain losses, claims, damages and liabilities, including
liabilities under the Securities Act.

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