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                                                                   EXHIBIT 10.48

                          REGISTRATION RIGHTS AGREEMENT


         REGISTRATION RIGHTS AGREEMENT (this "AGREEMENT"), dated as of February
9, 2001 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 holders (each, a "HOLDER" and
collectively, the "HOLDERS").

         WHEREAS:

         A.       In connection with the Placement Agent Agreement between the
parties hereto of even date herewith (the "PLACEMENT AGENT AGREEMENT"), the
Company has agreed to issue common stock purchase warrants to purchase an
aggregate of ten million (10,000,000) shares of the Company's common stock, par
value $0.00001 per share (the "COMMON STOCK"), at various exercise prices for a
term of five (5) years from the date of issuance of such warrants (individually,
a "WARRANT" and collectively, the "WARRANTS"). Capitalized terms not defined
herein shall have the meaning ascribed to them in the Placement Agent Agreement.

         B.       To induce the Placement Agent to enter to execute and deliver
the Placement Agent Agreement, the Company has agreed to provide certain
registration rights under the Securities Act of 1933, as amended, and the rules
and regulations thereunder, or any similar successor statute (collectively, the
"1933 ACT"), and applicable state securities laws, with respect to the shares of
Common Stock issuable upon exercise of the Warrants (the "WARRANT SHARES").

         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
Holder hereby agree as follows:

         1.       DEFINITIONS.

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

                  a.       "HOLDER" shall mean the person holding a Warrant or
Registrable Securities or securities convertible into Registrable Securities and
any person holding such securities to whom the rights under Section 2 have been
transferred in accordance with Section 9 hereof.

                  b.       "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.

                  c.       "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 Commission (the "SEC").

                  d.       "REGISTRABLE SECURITIES" means the 10,0000 shares of
the Company's Common Stock issuable to a Holder upon exercise of a Warrant.


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

         2.       COMPANY REGISTRATION.

                  a.       Notice of Registration. If the Company shall
determine to register any of its securities, either for its own account or the
account of a security holder or holders, other than (x) a registration relating
solely to employee benefit plans or (y) a registration relating solely to a Rule
145 transaction:

                           (A)      promptly give to each Holder written notice
thereof; and

                           (B)      include in such registration (and any
related qualification under blue sky laws or other compliance), and in any
underwriting involved therein, all the Registrable Securities specified in a
written request or requests, made within twenty (20) days after receipt of such
written notice from the Company, by the Holder.

                  b.       Underwriting.

                           (A)      If the  registration  of which the Company
gives notice is for a public offering involving an underwriting, the Company
shall so advise each Holder as a part of the written notice given pursuant to
Section 2. In such event the right of the Holder to registration pursuant to
this Section 2 shall be conditioned upon the Holder's participation in such
underwriting and the inclusion of Registrable Securities in the underwriting to
the extent provided herein. If a Holder proposes to distribute its securities
through such underwriting, the Holder shall (together with the Company) enter
into an underwriting agreement in customary form with the managing underwriter
selected for such underwriting by the Company. Notwithstanding any other
provision of this Section 2, if the managing underwriter determines that
marketing factors require a limitation of the number of shares to be
underwritten, the managing underwriter may limit or exclude some or all of the
Registrable Securities and other securities to be included in such registration.

                           (B)      If the Holder  disapproves  of the terms of
any such underwriting, the Holder may elect to withdraw therefrom by written
notice to the Company and the managing underwriter. Any securities excluded or
withdrawn from such underwriting shall be withdrawn from such registration, and
shall not be transferred in a public distribution prior to ninety (90) days
after the effective date of the registration statement relating thereto, or such
other shorter period of time as the underwriters may require.

                  (c)      Right to Terminate Registration. The Company shall
have the right to terminate or withdraw any registration initiated by it under
this Section 2 prior to the effectiveness of such registration whether or not
the Holder has elected to include securities in such registration. The
Registration Expenses of such withdrawn registration shall be borne by the
Company in accordance with Section 1.4 hereof.

         3.       RELATED OBLIGATIONS.

                  a.       The Company shall keep a Registration Statement
effective pursuant to Rule 415 at all times until the earlier of (i) the date on
which the Holders shall have sold all the Registrable Securities covered by such
Registration Statement or (ii) the date on which all of the


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Registrable Securities may be sold pursuant to Rule 144 (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-K, Form
10-Q or Form 8-K or any analogous report under the Securities Exchange Act of
1934, as amended (the "1934 ACT"), the Company shall have incorporated 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.

                  c.       The Company shall furnish to each Holder whose
Registrable Securities are included in any Registration Statement, without
charge, (i) at least one 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 Holder may
reasonably request) and (iii) such other documents as such Holder may reasonably
request from time to time in order to facilitate the disposition of the
Registrable Securities owned by such Holder.

                  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
(up to 10) in the United States as any Holder 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 Holder
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


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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 Holder 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 Holder. The Company shall also promptly notify each Holder 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 Holder 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.

                  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
Holder 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 Holder, the Company
shall furnish to such Holder, on the date of the effectiveness of the
Registration Statement and thereafter from time to time on such dates as a
Holder 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 Holders.

                  h.       Intentionally omitted.

                  i.       The Company shall hold in confidence and not make any
disclosure of information concerning a Holder 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 a Holder is sought in or by a court or governmental
body of competent jurisdiction or through other means, give prompt written
notice to such Holder and allow such Holder, at the Holder's expense, to
undertake appropriate action to prevent disclosure of, or to obtain a protective
order for, such information.


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                  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) secure designation and quotation of all the Registrable Securities covered
by the Registration Statement on the Nasdaq National Market or The Nasdaq
SmallCap Market or 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 Holders 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 Holders may reasonably
request and registered in such names as the Holders 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 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-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 ordered 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 Holders 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 Holders of Registrable
Securities pursuant to a Registration Statement.

         4.       OBLIGATIONS OF A HOLDER.

                  Each Holder 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 Holder will immediately discontinue disposition
of Registrable Securities pursuant to any Registration Statement(s) covering
such Registrable Securities until such Holder's receipt of the copies of the
supplemented or amended prospectus contemplated by Section 3(e) or receipt of


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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 a Holder in
connection with any sale of Registrable Securities with respect to which a
Holder has entered into a contract for sale prior to the Holder'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 Holder 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, including the Investors'
reasonable legal fees of one counsel for the Investors in an amount not to
exceed $5,000.

         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 Holder, the
directors, officers, partners, employees, agents, representatives of, and each
Person, if any, who controls any Holder 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
of the 1933 Act, the 1934 Act, any other law, including, without limitation, any
state securities law, or any rule or regulation thereunder 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 Holders 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


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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 Holder 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(d); 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 Holders pursuant to Section 9.

                  b.       In connection with a Registration Statement, each
Holder 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 who signs the Registration
Statement 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 Holder
expressly for use in connection with such Registration Statement; and, subject
to Section 6(d), such Holder 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 Holder, which consent
shall not be unreasonably withheld; provided, further, however, that the Holder
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 Holder 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 and shall
survive the transfer of the Registrable Securities by the Holders pursuant to
Section 9. 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 Holder prior to such Holder's use
of the prospectus to which the Claim relates.

                  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 counsel for such
Indemnified Person or Indemnified


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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. In the case of an Indemnified Person, legal counsel
referred to in the immediately preceding sentence shall be selected by the
Holders holding a majority in interest of the Registrable Securities included in
the Registration Statement to which the Claim relates. 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.

         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.


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         8.       REPORTS UNDER THE 1934 ACT.

                  With a view to making available to the Holders 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 Holders 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 and the filing of such
reports and other documents is required for the applicable provisions of Rule
144; and

                  c.       furnish to each Holder so long as such Holder 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 Holders to sell such securities pursuant to Rule 144 without
registration.

         9.       ASSIGNMENT OF REGISTRATION RIGHTS.

                  The rights under this Agreement shall be automatically
assignable by the Holders to any transferee of all or any portion of Registrable
Securities if: (i) the Holder agrees in writing with the transferee or assignee
to assign such rights, and a copy of such agreement is furnished to the Company
within a reasonable time after such assignment; (ii) the Company is, within a
reasonable time after such transfer or assignment, furnished with written notice
of (a) the name and address of such transferee or assignee, and (b) the
securities with respect to which such registration rights are being transferred
or assigned; and (iii) at or before the time the Company receives the written
notice contemplated by clause (ii) of this sentence the transferee or assignee
agrees in writing with the Company to be bound by all of the provisions
contained herein.

         10.      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 Holders who then hold at least two-thirds (2/3) of the Registrable
Securities. Any amendment or waiver effected in accordance with this Section 10
shall be binding upon each Holder 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.

         11.      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


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receives conflicting instructions, notices or elections from two 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 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:

                           ADVANCED VIRAL RESEARCH CORP.
                           200 Corporate Boulevard South
                           Yonkers, New York 10701
                           Attention:       Shalom Hirschman, M.D.
                           Telephone:       914-376-7383
                           Facsimile:       914-376-7368

                  with a copy to:

                           Wolf, Block, Schorr and Solis-Cohen, LLP
                           250 Park Avenue
                           New York, NY 10177
                           Attention: Robert Fischer, Esq.
                           Telephone:       212-883-4901
                           Facsimile:       212-986-0604

If to a Holder, to its address and facsimile number on the Schedule of Holders
attached hereto, with copies to such Holder's representatives as set forth on
the Schedule of Holders 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 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.

                  d.       The corporate laws of the State of Delaware shall
govern all issues concerning the relative rights of the Company and the Holders
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 York, without giving effect to any


                                       10
<PAGE>   11

choice of law or conflict of law provision or rule (whether of the State of New
York or any other jurisdiction) that would cause the application of the laws of
any jurisdiction other than the State of New York. Each party 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, 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 Placement Agent Agreement and the
Warrants constitute, collectively, 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 Placement Agent Agreement
and the Warrants supersede all prior agreements and understandings among the
parties hereto with respect to the subject matter hereof and thereof.

                  f.       Subject to the requirements of Section 9, 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 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.       All consents and other determinations to be made by
the Holders pursuant to this Agreement shall be made, unless otherwise specified
in this Agreement, by Holders holding a majority of the Registrable Securities.


                                       11
<PAGE>   12

                  k.       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.

                  l.       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.



                                       12
<PAGE>   13

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


                                     ADVANCED VIRAL RESEARCH CORP.


                                     By: /s/ Shalom Z. Hirschman, M.D.
                                        ---------------------------------------
                                          Name:  Shalom Z. Hirschman, M.D.
                                          Title: President

HOLDERS:


/s/ Mark Angelo                           /s/ Hunter Singer
------------------------------------      -------------------------------------
MARK ANGELO                               HUNTER SINGER


/s/ Joseph W. Donahue                     /s/ Robert Farrell
------------------------------------      -------------------------------------
JOSEPH W. DONAHUE                         ROBERT FARRELL


/s/ Hamid Fashandi                        /s/ Kimberly Holt-May
------------------------------------      -------------------------------------
HAMID FASHANDI                            KIMBERLY HOLT-MAY


/s/ Owen May                              /s/ Kevin Davis
------------------------------------      -------------------------------------
OWEN MAY                                  KEVIN DAVIS


/s/ Adam Goldberg
------------------------------------
ADAM GOLDBERG


/s/ Michael Jacobs
------------------------------------
MICHAEL JACOBS


                                       13
<PAGE>   14

                               SCHEDULE OF HOLDERS


<TABLE>
<S>                                            <C>
Mark Angelo                                    Hunter Singer
c/o May Davis Group, Inc.                      c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735               1 World Trade Center, Suite 8735
New York, NY 10048                             New York, NY 10048


Joseph Donahue                                 Robert Farrell
c/o May Davis Group, Inc.                      c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735               1 World Trade Center, Suite 8735
New York, NY 10048                             New York, NY 10048


Hamid Fashandi                                 Kimberly Holt-May
c/o May Davis Group, Inc.                      c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735               1 World Trade Center, Suite 8735
New York, NY 10048                             New York, NY 10048


Owen May                                       Kevin Davis
c/o May Davis Group, Inc.                      c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735               1 World Trade Center, Suite 8735
New York, NY 10048                             New York, NY 10048


Adam Goldberg
c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735
New York, NY 10048


Michael Jacobs

c/o May Davis Group, Inc.
1 World Trade Center, Suite 8735
New York, NY 10048
</TABLE>


                                       14