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                                                                    EXHIBIT 10.6

                          REGISTRATION RIGHTS AGREEMENT

         This Registration Rights Agreement (the"Agreement") is made as of
October 31, 1997 by and between Introgen Therapeutics, Inc., a Delaware
corporation (the "Company") and Nomura International plc ("Nomura").

                                    RECITALS

         1. The Company entered into a Series B Preferred Stock Purchase
Agreement wherein registration rights were granted to the holders of the Series
B Preferred Stock and certain holders of the Company's Series A Preferred Stock
and Common Stock.

         2. The Company entered into a Series C Preferred Stock Purchase
Agreement (the "Series C Agreement") wherein registration rights were granted to
the holders of the Series C Preferred Stock. In addition, the registration
rights of the Series C Agreement were substituted for those of the Series B
Preferred Stock Purchase Agreement.

         3. Section 7.14 of the Series C Agreement sets forth the limitations on
subsequent registration rights.

         4. Simultaneously herewith, the Company is issuing shares of Series D
Preferred Stock pursuant to a Placement Agreement among the Company, Nomura and
Nomura Securities International, Inc.

         5. The Company has agreed to provide Nomura and other Holders of the
Company's Series D Preferred Stock and their direct and indirect transferees the
registration rights as set forth in this Agreement subject to Section 13 hereof.

         NOW, THEREFORE, the Company covenants and agrees as follows:

1.       Definitions.  For purposes of this Agreement:


         (a) The term "register," "registered," and "registration" refer to a
registration effected by preparing and filing a registration statement or
similar document in compliance with the Act, and the declaration or ordering of
effectiveness of such registration statement or document;

         (b) The term "Registrable Securities" means (1) the Common Stock
issuable or issued upon conversion of the Company's Series D Preferred Stock and
(2) any Common Stock of the Company issued as (or issuable upon the conversion
or exercise of any warrant, right or other security which is issued as) a
dividend or other distribution with respect to, or in exchange for or in
replacement of, such Series D Preferred Stock, excluding in all cases, however,
(i) any Registrable Securities sold by a person in a transaction in which his
rights under this Agreement are not permitted to be assigned hereunder, or (ii)
any Registrable Securities sold to or through a broker or dealer or underwriter
in a public distribution or a public securities transaction.


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         (c) The number of shares of "Registrable Securities then outstanding"
shall be determined by the number of shares of Common Stock outstanding which
are, and the number of shares of Common Stock issuable pursuant to then
exercisable or convertible securities which are, Registrable Securities.

         (d) The term "Holder" means any person owning or having the right to
acquire Registrable Securities or any assignee thereof in accordance with
Section 13 hereof; and

         (e) The term "Form S-3" means such form under the Act as in effect on
the date hereof or any registration form under the Act subsequently adopted by
the Securities and Exchange Commission ("SEC") which permits inclusion or
incorporation of substantial information by reference to other documents filed
by the Company with the SEC.

         (f) The term "Act" shall mean the Securities Act of 1933, as amended.

2.       Request for Registration.


         (a) If the Company shall receive at any time after January 1, 1999, a
written request from the Holders of at least fifty percent (50%) of the
Registrable Securities then outstanding that the Company file a registration
statement under the Act covering the registration of at least forty percent
(40%) of the Registrable Securities (or a lesser percentage if the anticipated
aggregate offering price, net of underwriting discounts and commissions, would
exceed $10,000,000), then the Company shall, within ten (10) days of the receipt
thereof, give written notice of such request to all Holders and shall, subject
to the limitations of subsections 2(b) and (c), cause to become effective as
soon as practicable, and in any event within 120 days of the receipt of such
request, the registration under the Act of all Registrable Securities which the
Holders request to be registered within 20 days of the mailing of such written
notice by the Company.

         (b) The Company shall not be obligated to take any action to cause to
become effective any such registration, qualification or compliance pursuant to
subsection 2(a):

             (i) During the period starting with the date sixty (60) days prior
to the Company's estimated date of filing of, and ending on the date six months
immediately following the effective date of, any registration statement
pertaining to securities of the Company (other than a registration of securities
in a Rule 145 transaction or with respect to an employee benefit plan), provided
that the Company is actively employing in good faith all reasonable efforts to
cause such registration statement to become effective;

             (ii) After the Company has caused two registrations to become
effective pursuant to subsection 2(a);

             (iii) If the Company shall furnish to such Holders a certificate
signed by the President of the Company stating that in the good faith judgment
of the Board of Directors it would be seriously detrimental to the Company or
its shareholders for a registration statement to be filed at such time, then
the Company's obligation to use its best efforts to register, qualify or comply
under subsection 2(a) shall

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be deferred for a period not to exceed 120 days from the date of receipt of
written request from the Holders; provided, however, that the Company may not
utilize this right more than once in any twelve- month period.

         (c) If the Holders initiating the registration request hereunder
("Initiating Holders") intend to distribute the Registrable Securities covered
by their request by means of an underwriting, they shall so advise the Company
as a part of their request made pursuant to this Section 2 and the Company shall
include such information in the written notice referred to in subsection 2(a).
In such event, the right of any Holder to include his Registrable Securities in
such registration shall be conditioned upon such Holder's participation in such
underwriting and the inclusion of such Holder's Registrable Securities in the
underwriting (unless otherwise mutually agreed by a majority in interest of the
Holders requesting the registration and such Holder) to the extent provided
herein. All Holders proposing to distribute their securities through such
underwriting shall (together with the Company as provided in subsection 4(e))
enter into an underwriting agreement in customary form with the underwriter or
underwriters selected for such underwriting by a majority in interest of the
Holders requesting the registration and reasonably acceptable to the Company.
Notwithstanding any other provision of this Section 2, if the underwriter
advises the Holders requesting the registration that marketing factors require a
limitation of the number of shares to be underwritten, then the Initiating
Holders shall so advise all Holders of Registrable Securities which would
otherwise be underwritten pursuant hereto, and the number of shares of
Registrable Securities that may be included in the underwriting shall be
allocated among all Holders thereof, in proportion (as nearly as practicable) to
the amount of Registrable Securities of the Company owned by each Holder;
provided, however, that the number of shares of Registrable Securities to be
included in such underwriting shall not be reduced unless all other securities
are first entirely excluded from such underwriting.

3.       Company Registration. If (but without any obligation to do so) the
Company proposes to register (including for this purpose a registration effected
by the Company for shareholders other than the Holders) any of its stock or
other securities under the Act in connection with the public offering of such
securities solely for cash (other than a registration relating solely to the
sale of securities to participants in a Company stock plan, or a registration on
any form which does not include substantially the same information as would be
required to be included in a registration statement covering the sale of the
Registrable Securities), the Company shall, at such time, promptly give each
Holder written notice of such registration. Upon the written request of each
Holder given within twenty (20) days after mailing of written notice by the
Company, the Company shall, subject to the provisions of Section 8, cause to be
registered under the Act all of the Registrable Securities that each such Holder
has requested to be registered.

4.       Obligations of the Company. Whenever required under this Agreement to
effect the registration of any Registrable Securities, the Company shall, as
expeditiously as reasonably possible:

         (a) Prepare and file with the SEC a registration statement with respect
to such Registrable Securities and use its best efforts to cause such
registration statement to become effective, and, upon the request of the Holders
of a majority of the Registrable Securities registered thereunder, keep such
registration statement effective for up to sixty (60) days.


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         (b) Prepare and file with the SEC such amendments and supplements to
such registration statement and the prospectus used in connection with such
registration statement as may be necessary to comply with the provisions of the
Act with respect to the disposition of all securities covered by such
registration statement.

         (c) Furnish to the Holders such numbers of copies of a prospectus,
including a preliminary prospectus, in conformity with the requirements of the
Act, and such other documents as they may reasonably request in order to
facilitate the disposition of Registrable Securities owned by them.

         (d) Use its best efforts to register and qualify the securities covered
by such registration statement under such other securities or Blue Sky laws of
such jurisdictions as shall be reasonably requested by the Holders, provided
that the Company shall not be required in connection therewith or as a condition
thereto to qualify to do business or to file a general consent to service of
process in any such states or jurisdictions.

         (e) In the event of any underwritten public offering, enter into and
perform its obligations under an underwriting agreement, in usual and customary
form, with the managing underwriter of such offering. Each Holder participating
in such underwriting shall also enter into and perform its obligations under
such an agreement.

         (f) Notify each Holder of Registrable Securities covered by such
registration statement at any time when a prospectus relating thereto is
required to be delivered under the Act of the happening of any event as a result
of which the prospectus included in such registration statement, as then in
effect, includes an untrue statement of a material fact or omits to state a
material fact required to be stated therein or necessary to make the statements
therein not misleading in the light of the circumstances then existing.

         (g) Furnish, at the request of any Holder requesting registration of
Registrable Securities pursuant to this Agreement, on the date that such
Registrable Securities are delivered to the underwriters for sale in connection
with a registration pursuant to this Agreement, if such securities are being
sold through underwriters, or, if such securities are not being sold through
underwriters, on the date that the registration statement with respect to such
securities becomes effective, (i) an opinion, dated such date, of the counsel
representing the Company for the purposes of such registration, in form and
substance as is customarily given to underwriters in an underwritten public
offering, addressed to the underwriters, if any, and to the Holders requesting
registration of Registrable Securities and (ii) a letter dated such date, from
the independent certified public accountants of the Company, in form and
substance as is customarily given by independent certified public accountants to
underwriters in an underwritten public offering, addressed to the underwriters,
if any, and to the Holders requesting registration of Registrable Securities.

5.       Furnish Information. It shall be a condition precedent to the
obligations of the Company to take any action pursuant to this Agreement with
respect to the Registrable Securities of any selling Holder that such holder
shall furnish to the Company such information regarding itself, the Registrable
Securities

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held by it, and the intended method of disposition of such securities as shall
be required to effect the registration of such Holder's Registrable Securities.

6.       Expenses of Demand Registration. All expenses, other than underwriting
discounts and commissions and any fees and expenses of a special counsel of a
selling stockholder, incurred in connection with registrations, filings or
qualifications pursuant to Section 2, including (without limitation) all
registration, federal and state filing and qualification fees and expenses,
printers' and accounting fees and fees and disbursements of counsel for the
Company, shall be paid by the Company; provided, however, that the Company shall
not be required to pay for any expenses of any registration proceeding begun
pursuant to Section 2 if the registration request is subsequently withdrawn at
the request of the Holders of a majority of the Registrable Securities to be
registered (in which case all participating Holders shall bear such expenses),
unless the Holders of a majority of the Registrable Securities agree to forfeit
their right to one demand registration pursuant to Section 2; provided further,
however, that if at the time of such withdrawal, the Holders have learned of a
material adverse change in the condition, business, or prospects of the Company
from that known to the Holders at the time of their request, then the Holders
shall not be required to pay any of such expenses and shall retain their rights
pursuant to Section 2. The Company's obligations under this 6 shall apply to
each registration pursuant to Section 2.

7.       Expenses of Company Registration. The Company shall bear and pay all
expenses incurred in connection with any registration, filing or qualification
of Registrable Securities with respect to the registrations pursuant to Section
3 for each Holder (which right may be assigned as provided in Section 13),
including (without limitation) all registration, filing, qualification, printers
and accounting fees relating or apportionable thereto, but excluding
underwriting discounts and commissions relating to Registrable Securities and
any fees or expenses of a special counsel of a selling Holder.

8.       Underwriting Requirements. In connection with any offering involving an
underwriting of shares being issued by the Company, the Company shall not be
required under Section 3 to include any of the Holders' securities in such
underwriting: (i) unless they accept the terms of the underwriting as agreed
upon between the Company and the underwriters selected by it, and then only in
such quantity as is provided for herein or (ii) if inclusion would reduce the
amount of securities to be included in such registration pursuant to a request
under Section 7.2 of the Series C Agreement. If the underwriters determine that
marketing factors require a limitation of the number of shares to be
underwritten, the underwriters may limit the number of Registrable Securities to
be included in the registration on a pro- rata basis, or may exclude Registrable
Securities entirely from such registration (the securities so included to be
apportioned pro rata among the selling Holders according to the total amount of
securities entitled to be included therein owned by each selling Holder or in
such other proportions as shall mutually be agreed to by such selling Holders)
but in no event shall any shares being sold by a stockholder exercising a demand
registration right similar to that granted in Section 2 be excluded from such
offering. For purposes of apportionment, any selling Holder which is a Holder of
Registrable Securities and which is a partnership or corporation, the partners,
retired partners and shareholders of such Holder, or the estates and family
members of any such partners and retired partners and any trusts for the benefit
of any of the foregoing persons shall be deemed to be a single "selling Holder",
and any pro rata reduction with respect to such "selling Holder" shall be based
upon the aggregate amount of

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shares carrying registration rights owned by all entities and individuals
included in such "selling Holder", as defined in this sentence.

9.       Delay of Registration. No Holder shall have any right to obtain or seek
an injunction restraining or otherwise delaying any such registration as the
result of any controversy that might arise with respect to the interpretation or
implementation of this Agreement.

10.      Indemnification. In the event any Registrable Securities are included
in a registration statement under this Agreement:

         (a) To the extent permitted by law, the Company will indemnify and hold
harmless each Holder, any underwriter (as defined in the Act) for such Holder
and each person, if any, who controls such Holder or underwriter within the
meaning of the Act or the Securities Exchange Act of 1934, amended (the "1934
Act"), against any losses, claims, damages, or liabilities (joint or several) to
which they may become subject under the Act, the 1934 Act or other federal or
state law, insofar as such losses, claims, damages, or liabilities (or actions
in respect thereof) arise out of or are based upon any of the following
statements, omissions or violations (collectively a "Violation"): (i) any untrue
statement or alleged untrue statement of a material fact contained in such
registration statement, including any preliminary prospectus or final prospectus
contained therein or any amendments or supplements thereto, (ii) 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, or (iii) any
violation or alleged violation by the Company of the Act, the 1934 Act, any
state securities law or any rule or regulation promulgated under the Act, the
1934 Act or any state securities law; and the Company will pay to each such
Holder, underwriter or controlling person, as incurred, any legal or other
expenses reasonably incurred by them in connection with investigating or
defending any such loss, claim, damage, liability, or action; provided, however,
that the indemnity agreement contained in this subsection 10(a) shall not apply
to amounts paid in settlement of any such loss, claim, damage, liability, or
action if such settlement is effected without the consent of the Company (which
consent shall not be unreasonably withheld), nor shall the Company be liable in
any such case for any such loss, claim, damage, liability, or action to the
extent that it arises out of or is based upon a Violation which occurs in
reliance upon and in conformity with written information furnished expressly for
use in connection with such registration by any such Holder, underwriter or
controlling person.

         (b) To the extent permitted by law, each selling Holder will indemnify
and hold harmless the Company, each of its directors, each of its officers who
has signed the registration statement, each person, if any, who controls the
Company within the meaning of the Act, any underwriter, any other Holder selling
securities in such registration statement and any controlling person of any such
underwriter or other Holder, against any losses, claims, damages, or liabilities
(joint or several) to which any of the foregoing persons may become subject,
under the Act, the 1934 Act or other federal or state law, insofar as such
losses, claims, damages, or liabilities (or actions in respect thereto) arise
out of or are 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 by such Holder expressly for use in connection
with such registration; and each such Holder will pay, as incurred, any legal or
other expenses reasonably incurred by any person intended to be indemnified
pursuant to this

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subsection 10(b), in connection with investigating or defending any such loss,
claim, damage, liability, or action; provided, however, that the indemnity
agreement contained in this subsection 10(b) shall not apply to amounts paid in
settlement of any such loss, claim, damage, liability or action if such
settlement is effected without the consent of the Holder, which consent shall
not be unreasonably withheld; provided, that, in no event shall any indemnity
under this subsection 10(b) exceed the gross proceeds from the offering received
by such Holder.

         (c) Promptly after receipt by an indemnified party under this Section
10 of notice of the commencement of any action (including any governmental
action), such indemnified party will, if a claim in respect thereof is to be
made against any indemnifying party under this Section 10, 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 the defense thereof with counsel mutually
satisfactory to the parties; provided, however, that an indemnified party shall
have the right to retain its own counsel, with the fees and expenses to be paid
by the indemnifying party, if representation of such indemnified party by the
counsel retained by the indemnifying party would be inappropriate due to actual
or potential differing interests between such indemnified party and any other
party represented by such counsel in such proceeding. The failure to deliver
written notice to the indemnifying party within a reasonable time of the
commencement of any such action, if prejudicial to its ability to defend such
action, shall relieve such indemnifying party of any liability to the
indemnified party under this Section 10, but the omission so to deliver written
notice to the indemnifying party will not relieve it of any liability that it
may have to any indemnified party otherwise than under this Section 10.

         (d) The obligations of the Company and Holders under this Section 10
shall survive the completion of any offering of Registrable Securities in a
registration statement under this Agreement, and otherwise.

11.      Reports Under Securities Exchange Act of 1934. With a view to making
available to the Holders the benefits of Rule 144 promulgated under the Act and
any other rule or regulation of the SEC that may at any time permit a Holder to
sell securities of the Company to the public without registration or pursuant to
a registration on Form S-3, the Company agrees to:

         (a) make and keep public information available, as those terms are
understood and defined in SEC Rule 144, at all times after ninety (90) days
after the effective date of the first registration statement filed by the
Company for the offering of its securities to the general public;

         (b) take such action, including the voluntary registration of its
Common Stock under Section 12 of the 1934 Act, as is necessary to enable the
Holders to utilize Form S-3 for the sale of their Registrable Securities, such
action to be taken as soon as practicable after the end of the fiscal year in
which the first registration statement filed by the Company for the offering of
its securities to the general public is declared effective;

         (c) file with the SEC in a timely manner all reports and other
documents required of the Company under the Act and the 1934 Act; and


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         (d) furnish to any Holder, so long as the Holder owns any Registrable
Securities, forthwith upon request (i) a written statement by the Company that
it has complied with the reporting requirements of SEC Rule 144 (at any time
after ninety (90) days after the effective date of the first registration
statement filed by the Company), the Act and the 1934 Act (at any time after it
has become subject to such reporting requirements), or that it qualifies as a
registrant whose securities may be resold pursuant to Form S-3 (at any time
after it so qualifies), (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 in
availing any Holder of any rule or regulation of the SEC (exclusive of Rule
144A) which permits the selling of any such securities without registration or
pursuant to such form.

12.      Form S-3 Registration. In case the Company shall receive from any
Holder or Holders of the Registrable Securities a written request or requests
that the Company effect a registration on Form S-3 and any related qualification
or compliance with respect to shares of Registrable Securities the reasonably
anticipated aggregate price to the public of which, net of underwriting
discounts and commissions, if applicable, would exceed $1,000,000 all or a part
of the Registrable Securities owned by such Holder or Holders, the Company will:

         (a) promptly give written notice of the proposed registration, and any
related qualification or compliance, to all other Holders; and

         (b) as soon as practicable, effect such registration and all such
qualifications and compliances as may be so requested and as would permit or
facilitate the sale and distribution of all or such portion of such Holder's or
Holders' Registrable Securities as are specified in such request, together with
all or such portion of the Registrable Securities of any other Holder or Holders
joining in such request as are specified in a written request given within 15
days after receipt of such written notice from the Company; provided, however,
that the Company shall not be obligated to effect any such registration,
qualification or compliance, pursuant to this Section 12: (1) if Form S-3 is not
available for such offering by the Holders; (2) if the Holders, together with
the holders of any other securities of the Company entitled to inclusion in such
registration, propose to sell Registrable Securities and such other securities
(if any) at an aggregate price to the public (net of any underwriters' discounts
or commissions) of less than $1,000,000; (3) if the Company shall furnish to the
Holders a certificate signed by the President of the Company stating that in the
good faith judgment of the Board of Directors of the Company, it would be
seriously detrimental to the Company and its shareholders for such Form S-3
Registration to be effected at such time, in which event the Company shall have
the right to defer the filing of the Form S-3 registration statement for a
period of not more than 120 days after receipt of the request of the Holder or
Holders under this Section 12; provided, however, that the Company shall not
utilize this right more than once in any twelve (12) month period; or (4) in any
particular jurisdiction in which the Company would be required to qualify to do
business or to execute a general consent to service of process in effecting such
registration, qualification or compliance.

         (c) Subject to the foregoing, the Company shall file a registration
statement covering the Registrable Securities and other securities so requested
to be registered as soon as practicable after receipt of the request or requests
of the Holders. All expenses incurred in connection with the

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registrations requested pursuant to Section 12, (exclusive of underwriting
discounts and commissions and any fees and expenses of a special counsel to a
selling shareholder) shall be paid by the Company.

13.      Assignment of Registration Rights. The rights to cause the Company to
register Registrable Securities pursuant to this Agreement may be assigned by a
Holder to a transferee or assignee of such securities who acquires (i) at least
25,000 shares of Registrable Securities, or (ii) all shares of Registrable
Securities then held by such Holder if such Holder transfers all such
Registrable Securities to a single entity, provided the Company is, within a
reasonable time after such transfer, furnished with written notice of the name
and the address of such transferee or assignee and the securities with respect
to which such registration rights are being assigned; and provided, further,
that such assignment shall be effective only if immediately following such
transfer the further disposition of such securities by the transferee or
assignee is restricted under the Act. Notwithstanding the above, such rights may
be assigned by a Holder to a limited partner or general partner of the Holder
regardless of the number of shares acquired by such transferee.

14.      Limitations on Subsequent Registration Rights. From and after the date
of this Agreement, the Company shall not, without the prior written consent of
the Holders of a majority of the Registrable Securities, enter into any
agreement (other than an amendment to this agreement or supplemental agreement
effected in accordance with Section 15 of this Agreement) with any holder or
prospective holder of any securities of the Company which would allow such
holder or prospective holder (a) to include such securities in any registration
filed pursuant to Section 2 hereof, unless under the terms of such agreement
such holder or prospective holder may include such securities in any such
registration only to the extent that the inclusion of such securities will not
reduce the amount of the Registrable Securities of the Holders which are
included in any such registration or (b) to make a demand registration which
could result in such registration being declared effective prior to the date set
forth in subsection 2(a) or within six months of the effective date of any
registration effected pursuant to Section 2.

15.      Amendment of Registration Rights. Any provision 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 (i) the Company and (ii) the holders of more than fifty
percent (50%) of the Registrable Securities then outstanding, and with the same
consent the Company may enter into a supplemental agreement for the purpose of
adding any provisions to or changing in any manner or eliminating any of the
provisions of this Agreement. Any amendment, waiver or supplemental agreement
effected in accordance with this Section 15 shall be binding upon each holder
of any securities which are or at one time were Registrable Securities (or which
are or were convertible into Registrable Securities), each future holder of all
such securities, and the Company.

16.      Termination of Registration Rights. No Holder shall be entitled to
exercise any right provided for in this Agreement after six (6) years following
the consummation of the sale of securities pursuant to a registration statement
filed by the Company under the Act in connection with the initial underwritten
offering of its securities to the general public.



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17.      Miscellaneous.

         (a) GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED
UNDER THE LAWS OF THE STATE OF NEW YORK.

         (b) Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

         (c) Titles and Subtitles. The titles and subtitles used in this
Agreement are used for convenience only and are not to be considered in
construing or interpreting this Agreement.

         (d) Notices. Unless otherwise provided, any notice required or
permitted under this Agreement shall be given in writing and shall be deemed
effectively given upon personal delivery to the party to be notified or upon
deposit with the United States Post Office, by registered or certified mail, or
other courier service, postage prepaid and addressed to the party to be notified
at the address indicated for such party in the Company's stock records or in the
case of the Company on the first page of this Agreement, or at such other
address as such party may designate by ten (10) days' advance written notice to
the other parties.

         (e) Severability. If one or more provisions of this Agreement are held
to be unenforceable under applicable law, such provision shall be excluded from
this Agreement and the balance of the Agreement shall be interpreted as if such
provision were so excluded and shall be enforceable in accordance with its
terms.




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         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first set forth above.

                                   INTROGEN THERAPEUTICS, INC.


                                   By:
                                           -------------------------------------
                                   Title:
                                           -------------------------------------

                                   INVESTOR


                                   ---------------------------------------------
                                   (print name)

                                   ---------------------------------------------
                                   (signature)

                                   ---------------------------------------------
                                   (title, if applicable)

                                   Address:
                                           -------------------------------------

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

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


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