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                                                                   EXHIBIT 10.15

                         REGISTRATION RIGHTS AGREEMENT

          THIS REGISTRATION RIGHTS AGREEMENT, dated as of September __, 2001
between Ballsbridge Finance Ltd. ("Purchaser") and Hollis-Eden Pharmaceuticals,
Inc. (the "Company").

          WHEREAS, simultaneously with the execution and delivery of this
Agreement, pursuant to a Common Stock Purchase Agreement dated the date hereof
(the "Purchase Agreement") the Purchaser has committed to purchase up to
$10,000,000 of the Company's Common Stock (terms not defined herein shall have
the meanings ascribed to them in the Purchase Agreement) and Warrants; and

          WHEREAS, the Company desires to grant to the Purchaser the
registration rights set forth herein with respect to the Shares and the shares
issuable upon exercise of the Warrants from time to time (collectively, the
"Securities").

          NOW, THEREFORE, the parties hereto mutually agree as follows:

          Section 1.  Registrable Securities.  As used herein the term
                      ----------------------
"Registrable Security" means the Securities until (i) all Securities have been
disposed of pursuant to the Registration Statement, (ii) all Securities have
been sold under circumstances under which all of the applicable conditions of
Rule 144 (or any similar provision then in force) under the Securities Act
("Rule 144") are met, (iii) all Securities have been otherwise transferred to
persons who may trade such Securities without restriction under the Securities
Act, and the Company has delivered a new certificate or other evidence of
ownership for such Securities not bearing a restrictive legend or (iv) such time
as, in the opinion of counsel to the Company, all Securities may be sold without
any time, volume or manner limitations pursuant to Rule 144(k) (or any similar
provision then in effect) under the Securities Act.  The term "Registrable
Securities" means any and/or all of the securities falling within the foregoing
definition of a "Registrable Security."  In the event of any merger,
reorganization, consolidation, recapitalization or other change in corporate
structure affecting the Common Stock, such adjustment shall be deemed to be made
in the definition of "Registrable Security" as is appropriate in order to
prevent any dilution or enlargement of the rights granted pursuant to this
Agreement.

          Section 2.  Restrictions on Transfer.  The Purchaser acknowledges and
                      ------------------------
understands that in the absence of an effective Registration Statement
authorizing the resale of the Securities as provided herein, the Securities are
"restricted securities" as defined in Rule 144.  The Purchaser understands that
no disposition or transfer of the Securities may be made by Purchaser in the
absence of (i) an opinion of counsel to the Purchaser, in form and substance
reasonably satisfactory to the Company, that such transfer may be made without
registration under the Securities Act or (ii) such registration.

          With a view to making available to the Purchaser the benefits of Rule
144, the Company agrees to:
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               (a) comply with the provisions of paragraph (c)(1) of Rule 144;
and

               (b) file with the Commission in a timely manner all reports and
other documents required to be filed by the Company pursuant to Section 13 or
15(d) under the Exchange Act; and, if at any time it is not required to file
such reports but in the past had been required to or did file such reports, it
will, upon the request of the Purchaser, make available other information as
required by, and so long as necessary to permit sales of, its Registrable
Securities pursuant to Rule 144.

          Section 3.  Registration Rights With Respect to the Securities.
                      --------------------------------------------------

               (a) The Company agrees that it will prepare and file with the
Securities and Exchange Commission ("Commission"), within forty-five (45) days
after the date hereof, a registration statement on Form S-3, if the Company
qualifies to use Form S-3 in connection with the transactions contemplated by
the Purchase Agreement (or, if the Company does not so qualify, on Form S-1 or
other appropriate form of registration statement) under the Securities Act (the
"Registration Statement"), at the sole expense of the Company (except as
provided in Section 3(c) hereof), in respect of Purchaser, so as to permit a
public offering and resale of the Securities under the Securities Act by
Purchaser.

          The Company shall use its commercially reasonable efforts to cause the
Registration Statement to become effective as expeditiously as practicable but
in no event later than ninety (90) days from the date hereof or five (5) days of
SEC clearance and will within said five (5) days request acceleration of
effectiveness.  The Company will notify Purchaser of the effectiveness of the
Registration Statement within one Trading Day of such event.

               (b) The Company will maintain the Registration Statement or post-
effective amendment filed under this Section 3 hereof effective under the
Securities Act until the earliest of (i) the date that all the Securities have
been disposed of pursuant to the Registration Statement, (ii) the date that the
all of the Securities may be sold under the provisions of Rule 144 without
limitation as to volume, (iii) the date all Securities may be sold without
restriction under the Securities Act, and the Company has delivered a new
certificate or other evidence of ownership for such securities not bearing a
restrictive legend, or (iv) the date all Securities may be sold without any
time, volume or manner limitations pursuant to Rule 144(k) or any similar
provision then in effect under the Securities Act (the "Effectiveness Period").

               (c) All fees, disbursements and out-of-pocket expenses and costs
incurred by the Company in connection with the preparation and filing of the
Registration Statement under subparagraph 3(a) and in complying with applicable
securities and Blue Sky laws (including, without limitation, all attorneys' fees
of the Company) shall be borne by the Company.  The Company shall also bear the
costs and expenses of preparing and filing one prospectus supplement in
connection with a transfer by the Purchaser of all or a portion of the Warrants.
Prospectus supplements necessitated by subsequent transfers of Warrants, if any,
shall be at the expense of the Purchaser.  The Purchaser shall bear the cost of
underwriting and/or brokerage discounts, fees and commissions, if any,
applicable to the Securities being registered and the fees and expenses of its
counsel.  The Purchaser and its counsel shall have a reasonable

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period, not less than three (3) Trading Days, to review the proposed
Registration Statement or any amendment thereto, prior to filing with the
Commission, and the Company shall provide the Purchaser with copies of any
comment letters received from the Commission with respect thereto within two (2)
Trading Days of receipt thereof. Prior to the filing of the Registration
Statement pursuant to Section 3(a), the Company shall make reasonably available
for inspection by Purchaser, any underwriter participating in any disposition
pursuant to the Registration Statement, and any attorney, accountant or other
agent retained by the Purchaser or any such underwriter all relevant financial
and other records, pertinent corporate documents and properties of the Company
and its subsidiaries, and cause the Company's officers, directors and employees
to supply all information reasonably requested by the Purchaser or any such
underwriter, attorney, accountant or agent in connection with the Registration
Statement, in each case, as is customary for similar due diligence examinations;
provided, however, that all records, information and documents that are
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designated in writing by the Company, in good faith, as confidential,
proprietary or containing any material non-public information shall be kept
confidential by the Purchaser and any such underwriter, attorney, accountant or
agent (pursuant to an appropriate confidentiality agreement in the case of the
Purchaser, underwriter, attorney, accountant or agent), unless such disclosure
is made pursuant to judicial process in a court proceeding (after first giving
the Company an opportunity promptly to seek a protective order or otherwise
limit the scope of the information sought to be disclosed) or is required by
law, or such records, information or documents become available to the public
generally or through a third party not in violation of an accompanying
obligation of confidentiality; and provided further that, if the foregoing
                                   -------- -------
inspection and information gathering would otherwise disrupt the Company's
conduct of its business, such inspection and information gathering shall, to the
maximum extent possible, be coordinated on behalf of the Purchaser and the other
parties entitled thereto by one firm of counsel designed by and on behalf of the
majority in interest of Purchaser and other parties. The Company at its expense
will supply the Purchaser with copies of the Registration Statement and the
prospectus included therein and other related documents in such quantities as
may be reasonably requested by the Purchaser.

               (d) The Company shall not be required by this Section 3 to
include a Purchaser's Securities in any Registration Statement which is to be
filed if, in the opinion of counsel for both the Purchaser and the Company (or,
should they not agree, in the opinion of another counsel experienced in
securities law matters acceptable to counsel for the Purchaser and the Company)
the proposed offering or other transfer as to which such registration is
requested is exempt from applicable federal and state securities laws and would
result in all purchasers or transferees obtaining securities which are not
"restricted securities", as defined in Rule 144 under the Securities Act.

If at any time or from time to time after the effective date of the Registration
Statement, the Company notifies the Purchaser in writing of the existence of a
Blackout Event (as defined in Section 3(f) below), the Purchaser shall not offer
or sell any Securities or engage in any other transaction involving or relating
to Securities, from the time of the giving of notice with respect to a Blackout
Event until the Purchaser receives written notice from the Company that such
Blackout Event either has been disclosed in an effective post-effective
amendment to the Registration Statement or a valid prospectus supplement
thereto, or no longer constitutes a Blackout Event (the "Suspension Period");
provided, however, that, if a Suspension Period
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                                       3
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occurs during any period commencing on a Trading Day a Draw Down Notice is
deemed delivered and ending three (3) Trading Days following the end of the
corresponding Draw Down Pricing Period, then (i) the Draw Down shall terminate
immediately, (ii) there shall be a prompt Settlement of any Draw Down which has
not yet settled but as to which the corresponding Draw Down Pricing Period ended
prior to the date the Purchaser is deemed to have received the Company's
Suspension Period notice, and, thereafter, no further Settlements relating to
the relevant Draw Down Notice shall occur, and (iii) the Company shall
compensate the Purchaser for any net decline in the market value of any
Securities purchased by the Purchaser pursuant to the relevant Draw Down Notice,
and not resold, through the end of such Suspension Period, but only to the
extent of actual losses suffered by the Purchaser as a result of such decline.
Net decline shall be calculated as the difference between the highest VWAP
during the applicable Suspension Period and the VWAP on the Trading Day
immediately following a properly delivered notice to the Purchaser that such
Suspension Period has ended. If a Blackout Event shall occur prior to the date
the Registration Statement is filed, then the Company's obligation to file the
Registration Statement shall be delayed without penalty for not more than thirty
(30) calendar days.

               (e) "Blackout Event" means any of the following: (a) the
possession by the Company of material information that is not ripe for
disclosure in a registration statement, as determined in good faith by the Chief
Executive Officer or the Board of Directors of the Company or that disclosure of
such information in the Registration Statement would be detrimental to the
business and affairs of the Company; or (b) any material engagement or activity
by the Company which would, in the good faith determination of the Chief
Executive Officer or the Board of Directors of the Company, be adversely
affected by disclosure in a registration statement at such time, which
determination shall be accompanied by a good faith determination by the Chief
Executive Officer or the Board of Directors of the Company that the Registration
Statement would be materially misleading absent the inclusion of such
information or (c) an occurrence, event or state of facts that results in the
Registration Statement no longer being current, and requiring action on the
Company's part in order to cause the prospectus forming a part of the
Registration Statement to meet the requirements of Section 5 of the Securities
Act.

               (f) In the event that the Company does not qualify to use Form
S-3 for the transactions contemplated by the Purchase Agreement at the time of
filing the Registration Statement, but subsequently becomes so qualified, the
Company shall promptly prepare and file a post-effective amendment to the
Registration Statement, so that, upon the effectiveness of such post-effective
amendment, the Registration Statement will become a registration statement on
Form S-3.

          Section 4.  Cooperation with Company.  Purchaser will cooperate with
                      ------------------------
the Company in all respects in connection with this Agreement, including timely
supplying all information reasonably requested by the Company (which shall
include all information regarding the Purchaser and proposed manner of sale of
the Registrable Securities required to be disclosed in the Registration
Statement) and executing and returning all documents reasonably requested in
connection with the registration and sale of the Registrable Securities.  The
Purchaser shall consent to be named as an underwriter in the Registration
Statement. Purchaser acknowledges

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that in accordance with current Commission policy, the Purchaser will be named
as the underwriter of the Securities in the Registration Statement.

          Section 5.  Registration Procedures.  If and whenever the Company is
                      -----------------------
required by any of the provisions of this Agreement to effect the registration
of any of the Registrable Securities under the Act, the Company shall (except as
otherwise provided in this Agreement), as expeditiously as possible, subject to
the Purchaser's assistance and cooperation as reasonably required:

               (a) prepare and file with the Commission such amendments and
supplements to the Registration Statement and the prospectus used in connection
therewith as may be necessary to keep such registration statement effective and
to comply with the provisions of the Securities Act with respect to the sale or
other disposition of all securities covered by such registration statement
whenever the Purchaser of such Registrable Securities shall desire to sell or
otherwise dispose of the same (including prospectus supplements with respect to
the sales of securities from time to time in connection with a registration
statement pursuant to Rule 415 promulgated under the Securities Act) and (ii)
take all lawful action such that each of (A) the Registration Statement and any
amendment thereto does not, when it becomes effective, 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 not misleading and
(B) the prospectus forming part of the Registration Statement, and any amendment
or supplement thereto, does not at any time during the Registration Period
include 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;

               (b) prior to the filing with the Commission of any Registration
Statement (including any amendments thereto) and the distribution or delivery of
any prospectus (including any supplements thereto), provide draft copies thereof
to the Purchaser and reflect in such documents all such comments as the
Purchaser (and its counsel) reasonably may propose and (ii) furnish to the
Purchaser such numbers of copies of a prospectus including a preliminary
prospectus or any amendment or supplement to any prospectus, as applicable, in
conformity with the requirements of the Securities Act, and such other
documents, as the Purchaser may reasonably request in order to facilitate the
public sale or other disposition of the securities owned by the Purchaser.
Notwithstanding the foregoing, no prospectus supplement, the form of which has
previously been approved by the Purchaser, need be delivered in draft form to
the Purchaser;

               (c) promptly notify the Purchaser upon the occurrence of any of
the following events in respect of the Registration Statement or related
prospectus in respect of the Registrable Securities: (i) receipt of any request
for additional information from the SEC or any other federal or state
governmental authority during the period of effectiveness of the Registration
Statement the response to which would require any amendments or supplements to
the Registration Statement or related prospectus; (ii) the issuance by the SEC
or any other federal or state governmental authority of any stop order
suspending the effectiveness of the Registration Statement or the initiation of
any proceedings for that purpose; (iii) receipt of any notification with respect
to the suspension of the qualification or exemption from qualification of any of
the

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Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose; (iv) the happening of any event
that makes any statement made in the Registration Statement or related
prospectus or any document incorporated or deemed to be incorporated therein by
reference untrue in any material respect or that requires the making of any
changes in the Registration Statement, related prospectus or documents so that,
in the case of the Registration Statement, 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 not misleading, and
that in the case of the related prospectus, 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 the light of the
circumstances under which they were made, not misleading; and (v) the Company's
reasonable determination that a post-effective amendment to the Registration
Statement would be appropriate; and the Company will promptly make available to
the Purchaser any such supplement or amendment to the related prospectus. The
Company shall not deliver to the Purchaser any Draw Down Notice during the
continuation of any of the foregoing events;

               (d) list such Registrable Securities on the Principal Market, and
any other exchange on which the Common Stock of the Company is then listed, if
the listing of such Registrable Securities is then permitted under the rules of
such exchange or the Nasdaq Stock Market;

               (e) cooperate with the Purchaser to facilitate the timely
preparation and delivery of certificates for the Registrable Securities to be
offered pursuant to the Registration Statement and enable such certificates for
the Registrable Securities to be in such denominations or amounts, as the case
may be, as the Purchaser reasonably may request and registered in such names as
the Purchaser may request; and, within three (3) Trading Days after a
Registration Statement which includes Registrable Securities is declared
effective by the Commission, deliver and cause legal counsel selected by the
Company to deliver to the transfer agent for the Registrable Securities (with
copies to the Purchaser whose Registrable Securities are included in such
Registration Statement) an appropriate instruction and, to the extent necessary,
an opinion of such counsel;

               (f) take all such other lawful actions reasonably necessary to
expedite and facilitate the disposition by the Purchaser of their Registrable
Securities in accordance with the intended methods therefor provided in the
prospectus which are customary for issuers to perform under the circumstances;
and

               (g) maintain a transfer agent for its Common Stock..

          Section 6.  Indemnification.
                      ---------------

               (a) The Company agrees to indemnify and hold harmless the
Purchaser and each person, if any, who controls the Purchaser within the meaning
of the Securities Act ("Distributing Purchaser") against any losses, claims,
damages or liabilities, joint or several (which shall, for all purposes of this
Agreement, include, but not be limited to, all reasonable costs of defense and
investigation and all reasonable attorneys' fees), to which the Distributing

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<PAGE>

Purchaser may become subject, under the Securities Act or otherwise, insofar as
such losses, claims, damages or liabilities (or actions in respect thereof)
arise out of or are based upon any untrue statement or alleged untrue statement
of any material fact contained in the Registration Statement, or any related
preliminary prospectus, final prospectus or amendment or supplement thereto, or
arise out of or are based upon the omission or alleged omission to state therein
a material fact required to be stated therein or necessary to make the
statements therein not misleading; provided, however, that the Company will not
be liable in any such case to the extent that any such loss, claim, damage or
liability arises out of or is based upon an untrue statement or alleged untrue
statement or omission or alleged omission made in the Registration Statement,
preliminary prospectus, final prospectus or amendment or supplement thereto in
reliance upon, and in conformity with, written information furnished to the
Company by the Distributing Purchaser specifically for use in the preparation
thereof. This Section 6(a) shall not inure to the benefit of any Distributing
Purchaser with respect to any person asserting such loss, claim, damage or
liability who purchased the Registrable Securities which are the subject thereof
if the Distributing Purchaser failed to send or give (in violation of the
Securities Act or the rules and regulations promulgated thereunder) a copy of
the prospectus contained in such Registration Statement to such person at or
prior to the written confirmation to such person of the sale of such Registrable
Securities, where the Distributing Purchaser was obligated to do so under the
Securities Act or the rules and regulations promulgated thereunder. This
indemnity agreement will be in addition to any liability which the Company may
otherwise have.

               (b) Each Distributing Purchaser agrees that it will indemnify and
hold harmless the Company, and each officer, director of the Company or person,
if any, who controls the Company within the meaning of the Securities Act,
against any losses, claims, damages or liabilities (which shall, for all
purposes of this Agreement, include, but not be limited to, all reasonable costs
of defense and investigation and all reasonable attorneys' fees) to which the
Company or any such officer, director or controlling person may become subject
under the Securities Act or otherwise, insofar as such losses, claims, damages
or liabilities (or actions in respect thereof) arise out of or are based upon
any untrue statement or alleged untrue statement of any material fact contained
in the Registration Statement, or any related preliminary prospectus, final
prospectus or amendment or supplement thereto, or arise out of or are based upon
the omission or the alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein not misleading,
but in each case only to the extent that such untrue statement or alleged untrue
statement or omission or alleged omission was made in the Registration
Statement, preliminary prospectus, final prospectus or amendment or supplement
thereto in reliance upon, and in conformity with, written information furnished
to the Company by such Distributing Purchaser specifically for use in the
preparation thereof. This indemnity agreement will be in addition to any
liability which the Distributing Purchaser may otherwise have. Notwithstanding
anything to the contrary herein, the Distributing Purchaser shall not be liable
under this Section 6(b) for any amount in excess of the net proceeds to such
Distributing Purchaser as a result of the sale of Registrable Securities
pursuant to the Registration Statement.

               (c) Promptly after receipt by an indemnified party under this
Section 6 of notice of the commencement of any action, such indemnified party
will, if a claim in respect thereof is to be made against the indemnifying party
under this Section 6, notify the indemnifying

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party of the commencement thereof; but the omission so to notify the
indemnifying party will not relieve the indemnifying party from any liability
which it may have to any indemnified party except to the extent of actual
prejudice demonstrated by the indemnifying party. In case any such action is
brought against any indemnified party, and it notifies the indemnifying party of
the commencement thereof, the indemnifying party will be entitled to participate
in, and, to the extent that it may wish, jointly with any other indemnifying
party similarly notified, assume the defense thereof, subject to the provisions
herein stated and after notice from the indemnifying party to such indemnified
party of its election so to assume the defense thereof, the indemnifying party
will not be liable to such indemnified party under this Section 6 for any legal
or other expenses subsequently incurred by such indemnified party in connection
with the defense thereof other than reasonable costs of investigation, unless
the indemnifying party shall not pursue the action to its final conclusion. The
indemnified party shall have the right to employ separate counsel in any such
action and to participate in the defense thereof, but the fees and expenses of
such counsel shall not be at the expense of the indemnifying party if the
indemnifying party has assumed the defense of the action with counsel reasonably
satisfactory to the indemnified party; provided that if the indemnified party is
the Distributing Purchaser, the fees and expenses of such counsel shall be at
the expense of the indemnifying party if (i) the employment of such counsel has
been specifically authorized in writing by the indemnifying party, or (ii) the
named parties to any such action (including any impleaded parties) include both
the Distributing Purchaser and the indemnifying party and the Distributing
Purchaser shall have been advised by such counsel that there may be one or more
legal defenses available to the indemnifying party different from or in conflict
with any legal defenses which may be available to the Distributing Purchaser (in
which case the indemnifying party shall not have the right to assume the defense
of such action on behalf of the Distributing Purchaser, it being understood,
however, that the indemnifying party shall, in connection with any one such
action or separate but substantially similar or related actions in the same
jurisdiction arising out of the same general allegations or circumstances, be
liable only for the reasonable fees and expenses of one separate firm of
attorneys for the Distributing Purchaser, which firm shall be designated in
writing by the Distributing Purchaser and be approved by the indemnifying
party). No settlement of any action against an indemnified party shall be made
without the prior written consent of the indemnified party, which consent shall
not be unreasonably withheld.

          All fees and expenses of the indemnified party (including reasonable
costs of defense and investigation in a manner not inconsistent with this
Section and all reasonable attorneys' fees and expenses) shall be paid to the
indemnified party, as incurred, within ten (10) Trading Days of written notice
thereof to the indemnifying party; 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).

          Section 7.  Contribution.  In order to provide for just and equitable
                      ------------
contribution under the Securities Act in any case in which (i) the indemnified
party makes a claim for indemnification pursuant to Section 6 hereof but is
judicially determined (by the entry of a final judgment or decree by a court of
competent jurisdiction and the expiration of time to appeal or the denial of the
last right of appeal) that such indemnification may not be enforced in such case
notwithstanding the fact that the express provisions of Section 6 hereof provide
for

                                       8
<PAGE>

indemnification in such case, or (ii) contribution under the Securities Act
may be required on the part of any indemnified party, then the Company and the
applicable Distributing Purchaser shall contribute to the aggregate losses,
claims, damages or liabilities to which they may be subject (which shall, for
all purposes of this Agreement, include, but not be limited to, all reasonable
costs of defense and investigation and all reasonable attorneys' fees), in
either such case (after contribution from others) on the basis of relative fault
as well as any other relevant equitable considerations.  The relative fault
shall be determined by reference to, among other things, whether the untrue or
alleged untrue statement of a material fact or the omission or alleged omission
to state a material fact relates to information supplied by the Company on the
one hand or the applicable Distributing Purchaser on the other hand, and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such statement or omission.   The Company and the
Distributing Purchaser agree that it would not be just and equitable if
contribution pursuant to this Section 7 were determined by pro rata allocation
or by any other method of allocation which does not take account of the
equitable considerations referred to in this Section 7.  The amount paid or
payable by an indemnified party as a result of the losses, claims, damages or
liabilities (or actions in respect thereof) referred to above in this Section 7
shall be deemed to include any legal or other expenses reasonably incurred by
such indemnified party in connection with investigating or defending any such
action or claim. 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.

          Notwithstanding any other provision of this Section 7, in no event
shall any Purchaser be required to undertake liability to any person under this
Section 7 for any amounts in excess of the dollar amount of the net proceeds to
be received by the Purchaser from the sale of the Purchaser's Registrable
Securities (after deducting any fees, discounts and commissions applicable
thereto) pursuant to any Registration Statement under which such Registrable
Securities are to be registered under the Securities Act.

          Section 8.  Notices.  All notices, demands, requests, consents,
                      -------
approvals, and other communications required or permitted hereunder shall be in
writing and, unless otherwise specified herein, shall be delivered as set forth
in the Purchase Agreement.

          Section 9.  Assignment.  Neither this Agreement nor any rights of the
                      ----------
Purchaser or the Company hereunder may be assigned by either party to any other
person. Notwithstanding the foregoing, (a) the provisions of this Agreement
shall inure to the benefit of, and be enforceable by, any transferee of any of
the Common Stock purchased by the Purchaser pursuant to the Purchase Agreement
other than through open-market sales,  (b) upon the prior written consent of the
Company, which consent shall not be unreasonably withheld or delayed in the case
of an assignment to an affiliate of the Purchaser, the Purchaser's interest in
this Agreement may be assigned at any time, in whole or in part, to any other
person or entity (including any affiliate of the Purchaser) who agrees to be
bound hereby and (c) the Company may, without the consent of the Purchaser,
assign its rights and obligations under this Agreement to any person or entity
that controls, is controlled by or is under common control with the Company, and
the provisions hereof will inure to the benefit of and be binding upon each

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successor of the Company, whether by merger, consolidation, transfer of all or
substantially all assets, or otherwise.

          Section 10.  Counterparts/Facsimile.  This Agreement may be executed
                       ----------------------
in two or more counterparts, each of which shall constitute an original, but all
of which, when together shall constitute but one and the same instrument, and
shall become effective when one or more counterparts have been signed by each
party hereto and delivered to the other party.  In lieu of the original, a
facsimile transmission or copy of the original shall be as effective and
enforceable as the original.

          Section 11.  Remedies and Severability.  The remedies provided in this
                       -------------------------
Agreement are cumulative and not exclusive of any remedies provided by law.  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 best 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.

          Section 12.  Conflicting Agreements.  The Company shall not enter into
                       ----------------------
any agreement with respect to its securities that is inconsistent with the
rights granted to the holders of Registrable Securities in this Agreement or
otherwise prevents the Company from complying with all of its obligations
hereunder.

          Section 13.  Headings.  The headings in this Agreement are for
                       --------
reference purposes only and shall not affect in any way the meaning or
interpretation of this Agreement.

          Section 14.  Governing Law.  This Agreement shall be governed by and
                       -------------
construed in accordance with the laws of the State of California applicable to
contracts made in California by persons domiciled in California and without
regard to its principles of conflicts of laws. Any action may be brought as set
forth in the Purchase Agreement.  Any party shall have the right to seek
injunctive relief from any court of competent jurisdiction in any case where
such relief is available.  Any dispute under this Agreement shall be submitted
to arbitration under the American Arbitration Association (the "AAA") in New
York City, New York, and shall be finally and conclusively determined by the
decision of a board of arbitration consisting of three (3) members (hereinafter
referred to as the "Board of Arbitration") selected as according to the rules
governing the AAA.  The Board of Arbitration shall meet on consecutive business
days in New York City, New York, and shall reach and render a decision in
writing (concurred in by a majority of the members of the Board of Arbitration)
with respect to the amount, if any, which the losing party is required to pay to
the other party in respect of a claim filed.  In connection with rendering its
decisions, the Board of Arbitration shall adopt and follow the laws of the State
of New York.  To the extent practical, decisions of the Board of Arbitration
shall be rendered no more than thirty (30) calendar days following commencement
of proceedings with respect thereto. The Board of

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<PAGE>

Arbitration shall cause its written decision to be delivered to all parties
involved in the dispute. The Board of Arbitration shall be authorized and is
directed to enter a default judgment against any party refusing to participate
in the arbitration proceeding within thirty days of any deadline for such
participation. Any decision made by the Board of Arbitration (either prior to or
after the expiration of such thirty (30) calendar day period) shall be final,
binding and conclusive on the parties to the dispute, and entitled to be
enforced to the fullest extent permitted by law and entered in any court of
competent jurisdiction. The prevailing party shall be awarded its costs,
including attorneys' fees, from the non-prevailing party as part of the
arbitration award. Any party shall have the right to seek injunctive relief from
any court of competent jurisdiction in any case where such relief is available.
The prevailing party in such injunctive action shall be awarded its costs,
including attorney's fees, from the non-prevailing party.

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<PAGE>

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



                                        HOLLIS-EDEN PHARMACEUTICALS, INC.

                                        By:________________________________


                                        BALLSBRIDGE FINANCE LTD.

                                        By:________________________________
                                             Name:
                                             Title:

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