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                                                                   EXHIBIT 10.77


                     INVESTOR REGISTRATION RIGHTS AGREEMENT

         THIS REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of July
18, 2003, by and among ADVANCED VIRAL RESEARCH CORP., a Delaware corporation,
with its principal office located at 200 Corporate Boulevard South, Yonkers, New
York 10701 (the "COMPANY"), and the undersigned investors (each, an "INVESTOR"
and collectively, the "INVESTORS").

         WHEREAS:

         A. In connection with the Securities Purchase Agreement by and among
the parties hereto of even date herewith (the "SECURITIES PURCHASE AGREEMENT"),
the Company has agreed, upon the terms and subject to the conditions of the
Securities Purchase Agreement, to issue and sell to the Investors convertible
debentures (the "CONVERTIBLE DEBENTURES") which shall be convertible into that
number of shares of the Company's common stock, par value $0.00001 per share
(the "COMMON STOCK"), pursuant to the terms of the Securities Purchase Agreement
for an aggregate purchase price of up to One Million Dollars ($1,000,000).
Capitalized terms not defined herein shall have the meaning ascribed to them in
the Securities Purchase Agreement.

         B. To induce the Investors to execute and deliver the Securities
Purchase Agreement, the Company has agreed to provide certain registration
rights under the Securities Act of 1933, as amended, and the rules and
regulations there under, or any similar successor statute (collectively, the
"1933 ACT"), and applicable state securities laws.

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants contained herein and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Company and the
Investors hereby agree as follows:

         1. DEFINITIONS.

         As used in this Agreement, the following terms shall have the following
meanings:

                  (a) "PERSON" means a corporation, a limited liability company,
an association, a partnership, an organization, a business, an individual, a
governmental or political subdivision thereof or a governmental agency.

                  (b) "REGISTER," "REGISTERED," and "REGISTRATION" refer to a
registration effected by preparing and filing one or more Registration
Statements (as defined below) in compliance with the 1933 Act and pursuant to
Rule 415 under the 1933 Act or any successor rule providing for offering
securities on a continuous or delayed basis ("RULE 415"), and the declaration or
ordering of effectiveness of such Registration Statement(s) by the United States
Securities and Exchange SEC (the "SEC").

                  (c) "REGISTRABLE SECURITIES" means the shares of Common Stock
issuable to Investors upon conversion of the Convertible Debentures pursuant to
the Securities Purchase Agreement.

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                  (d) "REGISTRATION STATEMENT" means a registration statement
under the 1933 Act which covers the Registrable Securities.

         2. REGISTRATION.

                  (a) Subject to the terms and conditions of this Agreement, the
Company shall prepare and file, no later than thirty (30) days from the date
hereof (the "SCHEDULED FILING DEADLINE"), with the SEC a registration statement
on Form S-1 or SB-2 (or, if the Company is then eligible, on Form S-3) under the
1933 Act (the "INITIAL REGISTRATION STATEMENT") for the registration for the
resale by all Investors who purchased Convertible Debentures pursuant to the
Securities Purchase Agreement 78,125,000 shares of Common Stock to be issued
upon conversion of the Convertible Debentures issued pursuant to the Securities
Purchase Agreement. The Company shall cause the Registration Statement to remain
effective until all of the Registrable Securities have been sold. Prior to the
filing of the Registration Statement with the SEC, the Company shall furnish a
copy of the Initial Registration Statement to the Investors, and Butler
Gonzalez, LLP for their review and comment. The Investors and Butler Gonzalez
LLP shall furnish comments on the Initial Registration Statement to the Company
within twenty-four (24) hours of the receipt thereof from the Company.

                  (b) EFFECTIVENESS OF THE INITIAL REGISTRATION STATEMENT. The
Company shall use its best efforts (i) to have the Initial Registration
Statement declared effective by the SEC no later than one hundred thirty-five
(135) days after the date hereof (the "SCHEDULED EFFECTIVE DEADLINE") and (ii)
file a response to any comments received from the SEC to the Initial
Registration Statement and file an Amendment to the Initial Registration
Statement, if necessary, no later than thirty (30) days after the date the
Company receives a comment letter from the SEC, if any (the "Amendment
Deadline"); and (iii) to insure that the Initial Registration Statement and any
subsequent Registration Statement remains in effect until all of the Registrable
Securities have been sold, subject to the terms and conditions of this
Agreement.

                  (c) FAILURE TO FILE OR OBTAIN EFFECTIVENESS OF THE
REGISTRATION STATEMENT. In the event the Registration Statement is not filed by
the Scheduled Filing Deadline or is not declared effective by the SEC on or
before the Scheduled Effective Date, or the Company fails to file an Amendment
to the Registration Statement, if necessary, by the Amendment Deadline, or if
after the Registration Statement has been declared effective by the SEC, sales
cannot be made pursuant to the Registration Statement (whether because of a
failure to keep the Registration Statement effective, failure to disclose such
information as is necessary for sales to be made pursuant to the Registration
Statement, failure to register sufficient shares of Common Stock or otherwise
then as partial relief for the damages to any holder of Registrable Securities
by reason of any such delay in or reduction of its ability to sell the
underlying shares of Common Stock (which remedy shall not be exclusive of any
other remedies at law or in equity), the Company will pay as liquidated damages
(the "LIQUIDATED DAMAGES") to the Investor, at the Investor's option, either a
cash amount or shares of the Company's Common Stock within three (3) business
days, after demand therefore, equal to two percent (2%) of the liquidated value
of the Convertible Debentures outstanding as Liquidated Damages for each thirty
(30) day period after the Scheduled Filing Deadline or the Scheduled Effective
Date as the case may be. If paid in the form of Common Stock, the amount of
stock to be issued will be calculated as follows: the value of the stock shall
be the Closing Bid Price of the Company's Common Stock on the date the
Liquidated Damages payment is demanded.

                  (d) LIQUIDATED DAMAGES. The Company and the Investor hereto
acknowledge and agree that the sums payable under subsection 2(c) above shall

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constitute liquidated damages and not penalties. The parties further acknowledge
that (i) the amount of loss or damages likely to be incurred is incapable or is
difficult to precisely estimate, (ii) the amounts specified in such subsections
bear a reasonable relationship to, and are not plainly or grossly
disproportionate to the probable loss likely to be incurred in connection with
any failure by the Company to obtain or maintain the effectiveness of a
Registration Statement, (iii) one of the reasons for the Company and the
Investor reaching an agreement as to such amounts was the uncertainty and cost
of litigation regarding the question of actual damages, and (iv) the Company and
the Investor are sophisticated business parties and have been represented by
sophisticated and able legal counsel and negotiated this Agreement at arm's
length.

         3. RELATED OBLIGATIONS.

                  (a) The Company shall keep the Registration Statement
effective pursuant to Rule 415 at all times until the date on which the Investor
shall have sold all the Registrable Securities covered by such Registration
Statement (the "REGISTRATION PERIOD"), which Registration Statement (including
any amendments or supplements thereto and prospectuses contained therein) shall
not contain any 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 in which they were made, not misleading.

                  (b) The Company shall prepare and file with the SEC such
amendments (including post-effective amendments) and supplements to a
Registration Statement and the prospectus used in connection with such
Registration Statement, which prospectus is to be filed pursuant to Rule 424
promulgated under the 1933 Act, as may be necessary to keep such Registration
Statement effective at all times during the Registration Period, and, during
such period, comply with the provisions of the 1933 Act with respect to the
disposition of all Registrable Securities of the Company covered by such
Registration Statement until such time as all of such Registrable Securities
shall have been disposed of in accordance with the intended methods of
disposition by the seller or sellers thereof as set forth in such Registration
Statement. In the case of amendments and supplements to a Registration Statement
which are required to be filed pursuant to this Agreement (including pursuant to
this Section 3(b)) by reason of the Company's filing a report on Form 10-KSB,
Form 10-QSB or Form 8-K or any analogous report under the Securities Exchange
Act of 1934, as amended (the "1934 ACT"), the Company shall incorporate such
report by reference into the Registration Statement, if applicable, or shall
file such amendments or supplements with the SEC on the same day on which the
1934 Act report is filed which created the requirement for the Company to amend
or supplement the Registration Statement.

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                  (c) The Company shall furnish to each Investor whose
Registrable Securities are included in any Registration Statement, without
charge, (i) at least one (1) copy of such Registration Statement as declared
effective by the SEC and any amendment(s) thereto, including financial
statements and schedules, all documents incorporated therein by reference, all
exhibits and each preliminary prospectus, (ii) ten (10) copies of the final
prospectus included in such Registration Statement and all amendments and
supplements thereto (or such other number of copies as such Investor may
reasonably request) and (iii) such other documents as such Investor may
reasonably request from time to time in order to facilitate the disposition of
the Registrable Securities owned by such Investor.

                  (d) The Company shall use its best efforts to (i) register and
qualify the Registrable Securities covered by a Registration Statement under
such other securities or "blue sky" laws of such jurisdictions in the United
States as any Investor reasonably requests, (ii) prepare and file in those
jurisdictions, such amendments (including post-effective amendments) and
supplements to such registrations and qualifications as may be necessary to
maintain the effectiveness thereof during the Registration Period, (iii) take
such other actions as may be necessary to maintain such registrations and
qualifications in effect at all times during the Registration Period, and (iv)
take all other actions reasonably necessary or advisable to qualify the
Registrable Securities for sale in such jurisdictions; provided, however, that
the Company shall not be required in connection therewith or as a condition
thereto to (w) make any change to its certificate of incorporation or by-laws,
(x) qualify to do business in any jurisdiction where it would not otherwise be
required to qualify but for this Section 3(d), (y) subject itself to general
taxation in any such jurisdiction, or (z) file a general consent to service of
process in any such jurisdiction. The Company shall promptly notify each
Investor who holds Registrable Securities of the receipt by the Company of any
notification with respect to the suspension of the registration or qualification
of any of the Registrable Securities for sale under the securities or "blue sky"
laws of any jurisdiction in the United States or its receipt of actual notice of
the initiation or threat of any proceeding for such purpose.

                  (e) As promptly as practicable after becoming aware of such
event or development, the Company shall notify each Investor in writing of the
happening of any event as a result of which the prospectus included in a
Registration Statement, as then in effect, includes an untrue statement of a
material fact or omission 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 (provided that in no event shall such
notice contain any material, nonpublic information), and promptly prepare a
supplement or amendment to such Registration Statement to correct such untrue
statement or omission, and deliver ten (10) copies of such supplement or
amendment to each Investor. The Company shall also promptly notify each Investor
in writing (i) when a prospectus or any prospectus supplement or post-effective
amendment has been filed, and when a Registration Statement or any
post-effective amendment has become effective (notification of such
effectiveness shall be delivered to each Investor by facsimile on the same day
of such effectiveness), (ii) of any request by the SEC for amendments or
supplements to a Registration Statement or related prospectus or related
information, and (iii) of the Company's reasonable determination that a
post-effective amendment to a Registration Statement would be appropriate.

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                  (f) The Company shall use its best efforts to prevent the
issuance of any stop order or other suspension of effectiveness of a
Registration Statement, or the suspension of the qualification of any of the
Registrable Securities for sale in any jurisdiction within the United States of
America and, if such an order or suspension is issued, to obtain the withdrawal
of such order or suspension at the earliest possible moment and to notify each
Investor who holds Registrable Securities being sold of the issuance of such
order and the resolution thereof or its receipt of actual notice of the
initiation or threat of any proceeding for such purpose.

                  (g) At the reasonable request of any Investor, the Company
shall furnish to such Investor, on the date of the effectiveness of the
Registration Statement and thereafter from time to time on such dates as an
Investor may reasonably request (i) a letter, dated such date, from the
Company's independent certified public accountants in form and substance as is
customarily given by independent certified public accountants to underwriters in
an underwritten public offering, and (ii) an opinion, dated as of such date, of
counsel representing the Company for purposes of such Registration Statement, in
form, scope and substance as is customarily given in an underwritten public
offering, addressed to the Investors.

                  (h) The Company shall make available for inspection by (i) any
Investor and (ii) one (1) firm of accountants or other agents retained by the
Investors (collectively, the "INSPECTORS") all pertinent financial and other
records, and pertinent corporate documents and properties of the Company
(collectively, the "RECORDS"), as shall be reasonably deemed necessary by each
Inspector, and cause the Company's officers, directors and employees to supply
all information which any Inspector may reasonably request; provided, however,
that each Inspector shall agree, and each Investor hereby agrees, to hold in
strict confidence and shall not make any disclosure (except to an Investor) or
use any Record or other information which the Company determines in good faith
to be confidential, and of which determination the Inspectors are so notified,
unless (a) the disclosure of such Records is necessary to avoid or correct a
misstatement or omission in any Registration Statement or is otherwise required
under the 1933 Act, (b) the release of such Records is ordered pursuant to a
final, non-appealable subpoena or order from a court or government body of
competent jurisdiction, or (c) the information in such Records has been made
generally available to the public other than by disclosure in violation of this
or any other agreement of which the Inspector and the Investor has knowledge.
Each Investor agrees that it shall, upon learning that disclosure of such
Records is sought in or by a court or governmental body of competent
jurisdiction or through other means, give prompt notice to the Company and allow
the Company, at its expense, to undertake appropriate action to prevent
disclosure of, or to obtain a protective order for, the Records deemed
confidential.

                  (i) The Company shall hold in confidence and not make any
disclosure of information concerning an Investor provided to the Company unless
(i) disclosure of such information is necessary to comply with federal or state
securities laws, (ii) the disclosure of such information is necessary to avoid
or correct a misstatement or omission in any Registration Statement, (iii) the
release of such information is ordered pursuant to a subpoena or other final,
non-appealable order from a court or governmental body of competent
jurisdiction, or (iv) such information has been made generally available to the
public other than by disclosure in violation of this Agreement or any other
agreement. The Company agrees that it shall, upon learning that disclosure of
such information concerning an Investor is sought in or by a court or

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governmental body of competent jurisdiction or through other means, give prompt
written notice to such Investor and allow such Investor, at the Investor's
expense, to undertake appropriate action to prevent disclosure of, or to obtain
a protective order for, such information.

                  (j) The Company shall use its best efforts either to cause all
the Registrable Securities covered by a Registration Statement (i) to be listed
on each securities exchange on which securities of the same class or series
issued by the Company are then listed, if any, if the listing of such
Registrable Securities is then permitted under the rules of such exchange or
(ii) the inclusion for quotation on the National Association of Securities
Dealers, Inc. OTC Bulletin Board for such Registrable Securities. The Company
shall pay all fees and expenses in connection with satisfying its obligation
under this Section 3(j).

                  (k) The Company shall cooperate with the Investors who hold
Registrable Securities being offered and, to the extent applicable, to
facilitate the timely preparation and delivery of certificates (not bearing any
restrictive legend) representing the Registrable Securities to be offered
pursuant to a Registration Statement and enable such certificates to be in such
denominations or amounts, as the case may be, as the Investors may reasonably
request and registered in such names as the Investors may request.

                  (l) The Company shall use its best efforts to cause the
Registrable Securities covered by the applicable Registration Statement to be
registered with or approved by such other governmental agencies or authorities
as may be necessary to consummate the disposition of such Registrable
Securities.

                  (m) The Company shall make generally available to its security
holders as soon as practical, but not later than ninety (90) days after the
close of the period covered thereby, an earnings statement (in form complying
with the provisions of Rule 158 under the 1933 Act) covering a twelve (12) month
period beginning not later than the first day of the Company's fiscal quarter
next following the effective date of the Registration Statement.

                  (n) The Company shall otherwise use its best efforts to comply
with all applicable rules and regulations of the SEC in connection with any
registration hereunder.

                  (o) Within two (2) business days after a Registration
Statement which covers Registrable Securities is declared effective by the SEC,
the Company shall deliver, and shall cause legal counsel for the Company to
deliver, to the transfer agent for such Registrable Securities (with copies to
the Investors whose Registrable Securities are included in such Registration
Statement) confirmation that such Registration Statement has been declared
effective by the SEC in the form attached hereto as EXHIBIT A.

                  (p) The Company shall take all other reasonable actions
necessary to expedite and facilitate disposition by the Investors of Registrable
Securities pursuant to a Registration Statement.

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         4. OBLIGATIONS OF THE INVESTORS.

         Each Investor agrees that, upon receipt of any notice from the Company
of the happening of any event of the kind described in Section 3(f) or the first
sentence of 3(e), such Investor will immediately discontinue disposition of
Registrable Securities pursuant to any Registration Statement(s) covering such
Registrable Securities until such Investor's receipt of the copies of the
supplemented or amended prospectus contemplated by Section 3(e) or receipt of
notice that no supplement or amendment is required. Notwithstanding anything to
the contrary, the Company shall cause its transfer agent to deliver unlegended
certificates for shares of Common Stock to a transferee of an Investor in
connection with any sale of Registrable Securities with respect to which an
Investor has entered into a contract for sale prior to the Investor's receipt of
a notice from the Company of the happening of any event of the kind described in
Section 3(f) or the first sentence of 3(e) and for which the Investor has not
yet settled.

         5. EXPENSES OF REGISTRATION.

         All expenses incurred in connection with registrations, filings or
qualifications pursuant to Sections 2 and 3, including, without limitation, all
registration, listing and qualifications fees, printers, legal and accounting
fees shall be paid by the Company.

         6. INDEMNIFICATION.

         With respect to Registrable Securities which are included in a
Registration Statement under this Agreement:

                  (a) To the fullest extent permitted by law, the Company will,
and hereby does, indemnify, hold harmless and defend each Investor, the
directors, officers, partners, employees, agents, representatives of, and each
Person, if any, who controls any Investor within the meaning of the 1933 Act or
the 1934 Act (each, an "INDEMNIFIED PERSON"), against any losses, claims,
damages, liabilities, judgments, fines, penalties, charges, costs, reasonable
attorneys' fees, amounts paid in settlement or expenses, joint or several
(collectively, "CLAIMS") incurred in investigating, preparing or defending any
action, claim, suit, inquiry, proceeding, investigation or appeal taken from the
foregoing by or before any court or governmental, administrative or other
regulatory agency, body or the SEC, whether pending or threatened, whether or
not an indemnified party is or may be a party thereto ("INDEMNIFIED DAMAGES"),
to which any of them may become subject insofar as such Claims (or actions or
proceedings, whether commenced or threatened, in respect thereof) arise out of
or are based upon: (i) any untrue statement or alleged untrue statement of a
material fact in a Registration Statement or any post-effective amendment
thereto or in any filing made in connection with the qualification of the
offering under the securities or other "blue sky" laws of any jurisdiction in
which Registrable Securities are offered ("BLUE SKY FILING"), or the omission or
alleged omission to state a material fact required to be stated therein or
necessary to make the statements therein not misleading; (ii) any untrue
statement or alleged untrue statement of a material fact contained in any final
prospectus (as amended or supplemented, if the Company files any amendment
thereof or supplement thereto with the SEC) or the omission or alleged omission
to state therein any material fact necessary to make the statements made
therein, in light of the circumstances under which the statements therein were
made, not misleading; or (iii) any violation or alleged violation by the Company

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of the 1933 Act, the 1934 Act, any other law, including, without limitation, any
state securities law, or any rule or regulation there under relating to the
offer or sale of the Registrable Securities pursuant to a Registration Statement
(the matters in the foregoing clauses (i) through (iii) being, collectively,
"VIOLATIONS"). The Company shall reimburse the Investors and each such
controlling person promptly as such expenses are incurred and are due and
payable, for any legal fees or disbursements or other reasonable expenses
incurred by them in connection with investigating or defending any such Claim.
Notwithstanding anything to the contrary contained herein, the indemnification
agreement contained in this Section 6(a): (x) shall not apply to a Claim by an
Indemnified Person arising out of or based upon a Violation which occurs in
reliance upon and in conformity with information furnished in writing to the
Company by such Indemnified Person expressly for use in connection with the
preparation of the Registration Statement or any such amendment thereof or
supplement thereto; (y) shall not be available to the extent such Claim is based
on a failure of the Investor to deliver or to cause to be delivered the
prospectus made available by the Company, if such prospectus was timely made
available by the Company pursuant to Section 3(c); and (z) shall not apply to
amounts paid in settlement of any Claim if such settlement is effected without
the prior written consent of the Company, which consent shall not be
unreasonably withheld. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of the Indemnified Person
and shall survive the transfer of the Registrable Securities by the Investors
pursuant to Section 9 hereof.

                  (b) In connection with a Registration Statement, each Investor
agrees to severally and not jointly indemnify, hold harmless and defend, to the
same extent and in the same manner as is set forth in Section 6(a), the Company,
each of its directors, each of its officers, employees, representatives, or
agents and each Person, if any, who controls the Company within the meaning of
the 1933 Act or the 1934 Act (each an "INDEMNIFIED Party"), against any Claim or
Indemnified Damages to which any of them may become subject, under the 1933 Act,
the 1934 Act or otherwise, insofar as such Claim or Indemnified Damages arise
out of or is based upon any Violation, in each case to the extent, and only to
the extent, that such Violation occurs in reliance upon and in conformity with
written information furnished to the Company by such Investor expressly for use
in connection with such Registration Statement; and, subject to Section 6(d),
such Investor will reimburse any legal or other expenses reasonably incurred by
them in connection with investigating or defending any such Claim; provided,
however, that the indemnity agreement contained in this Section 6(b) and the
agreement with respect to contribution contained in Section 7 shall not apply to
amounts paid in settlement of any Claim if such settlement is effected without
the prior written consent of such Investor, which consent shall not be
unreasonably withheld; provided, further, however, that the Investor shall be
liable under this Section 6(b) for only that amount of a Claim or Indemnified
Damages as does not exceed the net proceeds to such Investor as a result of the
sale of Registrable Securities pursuant to such Registration Statement. Such
indemnity shall remain in full force and effect regardless of any investigation
made by or on behalf of such Indemnified Party. Notwithstanding anything to the
contrary contained herein, the indemnification agreement contained in this
Section 6(b) with respect to any prospectus shall not inure to the benefit of
any Indemnified Party if the untrue statement or omission of material fact
contained in the prospectus was corrected and such new prospectus was delivered
to each Investor prior to such Investor's use of the prospectus to which the
Claim relates.

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                  (c) Promptly after receipt by an Indemnified Person or
Indemnified Party under this Section 6 of notice of the commencement of any
action or proceeding (including any governmental action or proceeding) involving
a Claim, such Indemnified Person or Indemnified Party shall, if a Claim in
respect thereof is to be made against any indemnifying party under this Section
6, deliver to the indemnifying party a written notice of the commencement
thereof, and the indemnifying party shall have the right to participate in, and,
to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume control of the defense thereof
with counsel mutually satisfactory to the indemnifying party and the Indemnified
Person or the Indemnified Party, as the case may be; provided, however, that an
Indemnified Person or Indemnified Party shall have the right to retain its own
counsel with the fees and expenses of not more than one (1) counsel for such
Indemnified Person or Indemnified Party to be paid by the indemnifying party,
if, in the reasonable opinion of counsel retained by the indemnifying party, the
representation by such counsel of the Indemnified Person or Indemnified Party
and the indemnifying party would be inappropriate due to actual or potential
differing interests between such Indemnified Person or Indemnified Party and any
other party represented by such counsel in such proceeding. The Indemnified
Party or Indemnified Person shall cooperate fully with the indemnifying party in
connection with any negotiation or defense of any such action or claim by the
indemnifying party and shall furnish to the indemnifying party all information
reasonably available to the Indemnified Party or Indemnified Person which
relates to such action or claim. The indemnifying party shall keep the
Indemnified Party or Indemnified Person fully apprised at all times as to the
status of the defense or any settlement negotiations with respect thereto. No
indemnifying party shall be liable for any settlement of any action, claim or
proceeding effected without its prior written consent; provided, however, that
the indemnifying party shall not unreasonably withhold, delay or condition its
consent. No indemnifying party shall, without the prior written consent of the
Indemnified Party or Indemnified Person, consent to entry of any judgment or
enter into any settlement or other compromise which does not include as an
unconditional term thereof the giving by the claimant or plaintiff to such
Indemnified Party or Indemnified Person of a release from all liability in
respect to such claim or litigation. Following indemnification as provided for
hereunder, the indemnifying party shall be subrogated to all rights of the
Indemnified Party or Indemnified Person with respect to all third parties, firms
or corporations relating to the matter for which indemnification has been made.
The failure to deliver written notice to the indemnifying party within a
reasonable time of the commencement of any such action shall not relieve such
indemnifying party of any liability to the Indemnified Person or Indemnified
Party under this Section 6, except to the extent that the indemnifying party is
prejudiced in its ability to defend such action.

                  (d) The indemnification required by this Section 6 shall be
made by periodic payments of the amount thereof during the course of the
investigation or defense, as and when bills are received or Indemnified Damages
are incurred.

                  (e) The indemnity agreements contained herein shall be in
addition to (i) any cause of action or similar right of the Indemnified Party or
Indemnified Person against the indemnifying party or others, and (ii) any
liabilities the indemnifying party may be subject to pursuant to the law.

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         7. CONTRIBUTION.

         To the extent any indemnification by an indemnifying party is
prohibited or limited by law, the indemnifying party agrees to make the maximum
contribution with respect to any amounts for which it would otherwise be liable
under Section 6 to the fullest extent permitted by law; provided, however, that:
(i) no seller of Registrable Securities guilty of fraudulent misrepresentation
(within the meaning of Section 11(f) of the 1933 Act) shall be entitled to
contribution from any seller of Registrable Securities who was not guilty of
fraudulent misrepresentation; and (ii) contribution by any seller of Registrable
Securities shall be limited in amount to the net amount of proceeds received by
such seller from the sale of such Registrable Securities.

         8. REPORTS UNDER THE 1934 ACT.

         With a view to making available to the Investors the benefits of Rule
144 promulgated under the 1933 Act or any similar rule or regulation of the SEC
that may at any time permit the Investors to sell securities of the Company to
the public without registration ("RULE 144") the Company agrees to:

                  (a) make and keep public information available, as those terms
are understood and defined in Rule 144;

                  (b) file with the SEC in a timely manner all reports and other
documents required of the Company under the 1933 Act and the 1934 Act so long as
the Company remains subject to such requirements (it being understood that
nothing herein shall limit the Company's obligations under Section 4(c) of the
Securities Purchase Agreement) and the filing of such reports and other
documents as are required by the applicable provisions of Rule 144; and

                  (c) furnish to each Investor so long as such Investor owns
Registrable Securities, promptly upon request, (i) a written statement by the
Company that it has complied with the reporting requirements of Rule 144, the
1933 Act and the 1934 Act, (ii) a copy of the most recent annual or quarterly
report of the Company and such other reports and documents so filed by the
Company, and (iii) such other information as may be reasonably requested to
permit the Investors to sell such securities pursuant to Rule 144 without
registration.

         9. AMENDMENT OF REGISTRATION RIGHTS.

         Provisions of this Agreement may be amended and the observance thereof
may be waived (either generally or in a particular instance and either
retroactively or prospectively), only with the written consent of the Company
and Investors who then hold at least two-thirds (2/3) of the Registrable
Securities. Any amendment or waiver effected in accordance with this Section 9
shall be binding upon each Investor and the Company. No such amendment shall be
effective to the extent that it applies to fewer than all of the holders of the
Registrable Securities. No consideration shall be offered or paid to any Person
to amend or consent to a waiver or modification of any provision of any of this
Agreement unless the same consideration also is offered to all of the parties to
this Agreement.

                                       10
<PAGE>

         10. MISCELLANEOUS.

                  (a) A Person is deemed to be a holder of Registrable
Securities whenever such Person owns or is deemed to own of record such
Registrable Securities. If the Company receives conflicting instructions,
notices or elections from two (2) or more Persons with respect to the same
Registrable Securities, the Company shall act upon the basis of instructions,
notice or election received from the registered owner of such Registrable
Securities.

                  (b) Any notices, consents, waivers or other communications
required or permitted to be given under the terms of this Agreement must be in
writing and will be deemed to have been delivered: (i) upon receipt, when
delivered personally; (ii) upon receipt, when sent by facsimile (provided
confirmation of transmission is mechanically or electronically generated and
kept on file by the sending party); or (iii) one (1) business day after deposit
with a nationally recognized overnight delivery service, in each case properly
addressed to the party to receive the same. The addresses and facsimile numbers
for such communications shall be:

If to the Company, to:                 Advanced Viral Research Corp.
                                       200 Corporate Boulevard South
                                       Yonkers, New York 10701
                                       Attention:   Alan Gallantar
                                                    Chief Financial Officer
                                       Telephone:   (914) 376-7383
                                       Facsimile:   (914) 376-7638

With a copy to:                        Kirkpatrick & Lockhart LLP
                                       201 South Biscayne Boulevard - Suite 2000
                                       Miami, Florida 33131-2399
                                       Attention:   Clayton E. Parker, Esq.
                                       Telephone:   (305) 539-3300
                                       Facsimile:   (305) 358-7095

If to an Investor, to its address and facsimile number on the Schedule of
Investors attached hereto, with copies to such Investor's representatives as set
forth on the Schedule of Investors or to such other address and/or facsimile
number and/or to the attention of such other person as the recipient party has
specified by written notice given to each other party five (5) days prior to the
effectiveness of such change. Written confirmation of receipt (A) given by the
recipient of such notice, consent, waiver or other communication, (B)
mechanically or electronically generated by the sender's facsimile machine
containing the time, date, recipient facsimile number and an image of the first
page of such transmission or (C) provided by a courier or overnight courier
service shall be rebuttable evidence of personal service, receipt by facsimile
or receipt from a nationally recognized overnight delivery service in accordance
with clause (i), (ii) or (iii) above, respectively.

                  (c) Failure of any party to exercise any right or remedy under
this Agreement or otherwise, or delay by a party in exercising such right or
remedy, shall not operate as a waiver thereof.

                                       11
<PAGE>

                  (d) The laws of the State of Delaware shall govern all issues
concerning the relative rights of the Company and the Investors as its
stockholders. All other questions concerning the construction, validity,
enforcement and interpretation of this Agreement shall be governed by the
internal laws of the State of New Jersey, without giving effect to any choice of
law or conflict of law provision or rule (whether of the State of New Jersey or
any other jurisdiction) that would cause the application of the laws of any
jurisdiction other than the State of New Jersey. Each party hereby irrevocably
submits to the non-exclusive jurisdiction of the Superior Courts of the State of
New Jersey, sitting in Hudson County, New Jersey and federal courts for the
District of New Jersey sitting Newark, New Jersey, for the adjudication of any
dispute hereunder or in connection herewith or with any transaction contemplated
hereby or discussed herein, 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 brought in an inconvenient forum or that the venue of such suit,
action or proceeding is improper. Each party 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 to such party at the address for such
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. If any provision of this Agreement shall be invalid or
unenforceable in any jurisdiction, such invalidity or unenforceability shall not
affect the validity or enforceability of the remainder of this Agreement in that
jurisdiction or the validity or enforceability of any provision of this
Agreement in any other jurisdiction. EACH PARTY HEREBY IRREVOCABLY WAIVES ANY
RIGHT IT MAY HAVE, AND AGREES NOT TO REQUEST, A JURY TRIAL FOR THE ADJUDICATION
OF ANY DISPUTE HEREUNDER OR IN CONNECTION HEREWITH OR ARISING OUT OF THIS
AGREEMENT OR ANY TRANSACTION CONTEMPLATED HEREBY.

                  (e) This Agreement, the Irrevocable Transfer Agent
Instructions, the Securities Purchase Agreement and related documents including
the Convertible Debentures and the Escrow Agreement dated the date hereof by and
among the Company, the Investors set forth on the Schedule of Investors attached
hereto and Butler Gonzalez LLP (the "ESCROW AGREEMENT") constitute the entire
agreement among the parties hereto with respect to the subject matter hereof and
thereof. There are no restrictions, promises, warranties or undertakings, other
than those set forth or referred to herein and therein. This Agreement, the
Irrevocable Transfer Agent Instructions, the Securities Purchase Agreement and
related documents including the Convertible Debentures and the Escrow Agreement
supersede all prior agreements and understandings among the parties hereto with
respect to the subject matter hereof and thereof.

                  (f) This Agreement shall inure to the benefit of and be
binding upon the permitted successors and assigns of each of the parties hereto.

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

                  (h) This Agreement may be executed in identical counterparts,
each of which shall be deemed an original but all of which shall constitute one
and the same agreement. This Agreement, once executed by a party, may be

                                       12
<PAGE>

delivered to the other party hereto by facsimile transmission of a copy of this
Agreement bearing the signature of the party so delivering this Agreement.

                  (i) Each party shall do and perform, or cause to be done and
performed, all such further acts and things, and shall execute and deliver all
such other agreements, certificates, instruments and documents, as the other
party may reasonably request in order to carry out the intent and accomplish the
purposes of this Agreement and the consummation of the transactions contemplated
hereby.

                  (j) The language used in this Agreement will be deemed to be
the language chosen by the parties to express their mutual intent and no rules
of strict construction will be applied against any party.

                  (k) This Agreement is intended for the benefit of the parties
hereto and their respective permitted successors and assigns, and is not for the
benefit of, nor may any provision hereof be enforced by, any other Person.



         IN WITNESS WHEREOF, the parties have caused this Investor Registration
Rights Agreement to be duly executed as of day and year first above written.

                                            COMPANY:
                                            ADVANCED VIRAL RESEARCH CORP.


                                            By:  /s/ SHALOM Z. HIRSCHMAN
                                               ---------------------------------
                                            Name:  Shalom Z. Hirschman
                                            Title: Chief Executive Officer

                                       13
<PAGE>




                                   SCHEDULE I

                               SCHEDULE OF BUYERS

<TABLE>
<CAPTION>
                                                                                           ADDRESS/FACSIMILE
            NAME                               SIGNATURE                                    NUMBER OF BUYER
----------------------------       --------------------------------                 ------------------------------
<S>                                <C>                                              <C>                       <C>
Cornell Capital Partners, LP       By:      Yorkville Advisors, LLC                 101 Hudson Street - Suite 3606
                                   Its:     General Partner                         Jersey City, NJ 07303
                                                                                    Facsimile: (201) 985-8266

                                   By: /s/ MARK ANGELO
                                      --------------------------
                                   Name: Mark Angelo
                                   Title: Portfolio Manager
</TABLE>