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                                                                     EXHIBIT 4.7

                                                              Confidential Draft

                                                                       Exhibit A

                          REGISTRATION RIGHTS AGREEMENT

                  This Registration Rights Agreement (the "Agreement") is
executed as of the 14th day of March, 2000 by BioNumerik Pharmaceuticals, Inc.,
a Texas corporation (the "Company") and Grelan Pharmaceutical Co., Ltd., a
Japanese corporation ("Grelan" or the "Purchaser").

                              W I T N E S S E T H:

                  WHEREAS, the Purchaser is purchasing shares of the Company's
Preferred Stock (as defined herein) with the understanding that the Company is
granting certain registration rights to the Purchaser.

                  NOW, THEREFORE, the Company grants the registration rights
contained herein to the Purchaser, subject to the terms and conditions contained
herein:

                  1. CERTAIN DEFINITIONS. As used in this Agreement, the
following terms shall have the following respective meanings:

                  "Commission" means the Securities and Exchange Commission or
any other federal agency at the time administering the Securities Act.

                  "Common Stock" means the Common Stock, par value $.01 per
share, of the Company.

                  "Conversion Shares" means the shares of Common Stock issued
and issuable upon conversion of the Preferred Stock.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended, or any similar federal statute and the rules and regulations of the
Commission thereunder, all as the same shall be in effect at the time.

                  "Holders" means the Purchaser and any holder of Registrable
Securities to whom the registration rights conferred by this Agreement have been
transferred in compliance with Section 2.10 hereof.

                  "Initiating Holders" means any Holder or Holders who in the
aggregate hold more than fifty percent (50%) of the then-outstanding Registrable
Securities, but no less than the number of Registrable Securities issued or
issuable upon conversion of twenty five percent (25%) of the total number of
shares of Preferred Stock issued by the Company to the Purchaser.

                  "Preferred Stock" means the Series F Convertible Preferred
Stock, par value $.01 per share, of the Company.

                  "Registrable Securities" means (i) the Conversion Shares and
(ii) any Common Stock issued as a dividend or other distribution with respect to
or in exchange for or in replacement of the
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Conversion Shares or Preferred Stock, provided, however, that Registrable
Securities shall not include any shares of Common Stock which have previously
been registered or which have been sold pursuant to Rule 144.

                  The terms "register," "registered" and "registration" refer to
a registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.

                  "Rule 144" means Rule 144 as promulgated by the Commission
under the Securities Act, as such Rule may be amended from time to time, or any
similar successor rule that may be promulgated by the Commission.

                  "Series A Persons" means those persons entitled to
registration rights pursuant to Section 10 of the Preferred Stock Purchase
Agreement dated February 19, 1993 between BioNumerik Pharmaceuticals, Inc., a
Delaware corporation and predecessor by merger to the Company ("BioNumerik
Delaware"), and certain purchasers of its securities, as amended.

                  "Series B Persons" means those persons entitled to
registration rights pursuant to that certain Registration Rights Agreement (the
"Series B Registration Rights Agreement") dated as of August 8, 1994 and
relating to registration rights granted by BioNumerik Delaware to purchasers of
its Series B Convertible Preferred Stock.

                  "Series C Persons" means those persons entitled to
registration rights pursuant to that certain Registration Rights Agreement (the
"Series C Registration Rights Agreement") dated as of August 24, 1995 and
relating to registration rights granted by the Company to purchasers of its
Series C Convertible Preferred Stock.

                  "Series D Persons" means those persons entitled to
registration rights pursuant to that certain Registration Rights Agreement (the
"Series D Registration Rights Agreement") dated as of July 10, 1996 and relating
to registration rights granted by the Company to purchasers of its Series D
Convertible Preferred Stock.

                  "Series E Persons" means those persons entitled to
registration rights pursuant to that certain Registration Rights Agreement (the
"Series E Registration Rights Agreement") dated as of January 21, 1998 and
relating to registration rights granted by the Company to purchasers of its
Series E Convertible Preferred Stock.

                  "Securities Act" means the Securities Act of 1933, as amended,
or any similar federal statute and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

                  For purposes of the definitions of "Holder" and "Initiating
Holders" above, holders of Preferred Stock shall be deemed to be the holders of
Registrable Securities issuable upon conversion thereof; and for the purpose of
calculating any percentage of Registrable Securities, the calculation shall be
made as if the Preferred Stock had been fully converted.



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<PAGE>
                  2. REGISTRATION OF REGISTRABLE SECURITIES.

                  2.1 Registration on Request.

                  (a) Request. Subject to the limitations provided herein,
commencing on December 31, 2001, or on the first anniversary of the effective
date of the Company's first registration statement under the Securities Act,
whichever shall first occur, until the fifth anniversary of the effective date
of the Company's first registration statement under the Securities Act, upon the
written request (specifying that it is being made pursuant to this Section 2.1)
of the Initiating Holders, requesting that the Company effect the registration
under the Securities Act of at least fifty percent (50%) of the then-outstanding
Registrable Securities, but no less than the number of Registrable Securities
issued or issuable upon conversion of twenty five percent (25%) of the total
number of shares of Preferred Stock issued by the Company to the Purchaser, and
specifying (x) the intended method of disposition thereof, (y) whether or not
such requested registration is to be an underwritten offering, and (z) the price
range (net of underwriting discounts and commissions) acceptable to such Holder
or Holders to be received for such Registrable Securities, the Company will
within 10 business days after the Company receives such written request give
written notice of such requested registration to all other Holders of
Registrable Securities and thereupon the Company will use reasonable efforts to
effect the registration under the Securities Act of:

                  (i) the Registrable Securities which the Company has been so
         requested to register by such Initiating Holders, and

                  (ii) all other Registrable Securities which the Company has
         been requested to register by the other Holders thereof by written
         request given to the Company within 15 days after the giving of such
         written notice by the Company (which request shall specify the same
         information called for by the original request to effect registration
         described above), all to the extent requisite to permit the disposition
         (in accordance with Section 2.1(b) hereof) of the Registrable
         Securities so to be registered.

                  (b) Method of Distribution. The Holders of 51% of the
Registrable Securities to be included in such registration statement shall
determine the method of distribution of the Registrable Securities so included;
provided, however, that if no agreement of Holders of 51% or more of the
Registrable Securities to be included in such registration statement is
obtained, then if Holders of more than 30% of the Registrable Securities to be
included in such registration statement request an underwritten public offering,
an underwritten public offering shall be the method of distribution with other
methods permitted to the extent the managing underwriter for such offering, in
its sole discretion, agrees to other methods of distribution being covered by
such registration statement.

                  (c) Registration of Other Securities. Whenever the Company
shall effect a registration pursuant to this Section 2.1 in connection with an
underwritten offering, no securities other than Registrable Securities shall be
included among the securities covered by such registration unless (i) the
managing underwriter of such offering shall have advised each Holder of
Registrable Securities to be covered by such registration in writing that the
inclusion of such other securities would not adversely affect such offering or
(ii) the Holders of more than 51% or more of all Registrable Securities to be
covered by such registration shall have consented in writing to the inclusion of
such other securities; provided, however, that the rights of Holders hereunder
shall be


                                       3
<PAGE>
subject to (A) the prior right of Series A Persons requesting registration
(whether pursuant to "demand" or "piggyback" registration rights) to include all
of the securities requested to be registered by such Series A Persons in such
registration, and (B) the concurrent right of Series B Persons, Series C
Persons, Series D Persons, Series E Persons, and persons holding securities
obtained through the exercise of warrants issued to certain placement agents and
finders in connection with the sale of the Company's Series E Convertible
Preferred Stock (the "Warrant Purchasers") requesting registration pursuant to
the Series B Registration Rights Agreement, the Series C Registration Rights
Agreement, the Series D Registration Rights Agreement, the Series E Registration
Rights Agreement, and/or the agreement granting registration rights to the
Warrant Purchasers (the "Warrant Purchaser Registration Agreement") (whether
pursuant to "demand" or "piggyback" registration rights) to include securities
in such registration on a pro rata basis with the Registrable Securities of
Holders to be included in such registration, so that the relative proportion of
the amount of securities held by Series B Persons, Series C Persons, Series D
Persons, Series E Persons, Warrant Purchasers and Holders that are actually
included in such registration is the same as the relative proportion of the
total amount of securities held by Series B Persons, Series C Persons Series D
Persons, Series E Persons, Warrant Purchasers and Holders that are requested to
be included in such registration pursuant to the Series B Registration Rights
Agreement, the Series C Registration Rights Agreement, the Series D Registration
Rights Agreement, the Series E Registration Rights Agreement, the Warrant
Purchaser Registration Agreement or this Agreement, as the case may be.

                  (d) Registration Statement Form. Registrations under this
Section 2.1 shall be on such appropriate registration form of the Commission (i)
as shall be selected by the Company, and (ii) as shall permit the disposition of
such Registrable Securities in accordance with the method or methods of
disposition selected pursuant to Section 2.1(b) hereof.

                  (e) Expenses. Except as otherwise provided in this Section
2.1(e) or in Section 2.1(i), the Company shall bear all expenses incurred in
connection with two effective registrations pursuant to Section 2.1 hereof and
each registration pursuant to Section 2.2 hereof (excluding in each case
underwriting discounts and commissions applicable to Registrable Securities),
including, without limitation, in each case: (i) all registration, filing and
National Association of Securities Dealers fees; (ii) all fees and expenses of
complying with securities or blue sky laws; (iii) all word processing,
duplicating and printing expenses, messenger, delivery and shipping expenses;
(iv) the fees and disbursements of the accountants and counsel for the Company
including the expenses of any special audits or "cold comfort" letters or
opinions required by or incident to such registrations; (v) the fees and
disbursements of the accountants and counsel for the Company for services
rendered in connection with inclusion of Registrable Securities in the
registration; provided, however, that if the accountants or the counsel for the
Company refuse or decline to undertake such representation because of an actual
or perceived conflict of interest or otherwise, then the Company shall bear the
reasonable fees and disbursements of one firm of counsel and one firm of
accountants (as appropriate) retained by the Holders of such Registrable
Securities; (vi) premiums and other costs of policies of insurance maintained
for the benefit of the Company against liabilities arising out of the public
offering of the Registrable Securities; (vii) any fees and disbursements of
underwriters customarily paid by issuers or sellers of securities, but excluding
underwriting discounts and commissions, if any. In all cases, each Holder of
Registrable Securities shall pay the underwriting discounts and commissions
applicable to the securities sold by such Holder.


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<PAGE>
                  (f) Effective Registration Statement. The Company's obligation
to effect a registration requested pursuant to this Section 2.1 shall not be
deemed to have been fulfilled (i) unless a registration statement with respect
thereto has become effective (unless a substantial cause of the failure of such
registration statement to become effective shall be attributable to one or more
Holders of Registrable Securities whose securities were to have been included in
such registration statement), (ii) if after it has become effective, such
registration is interfered with by any stop order, injunction or other order or
requirement of the Commission or other governmental agency or court for any
reason, resulting in a failure to consummate the offering of Registrable
Securities offered thereby, (iii) if after a registration statement with respect
thereto has become effective, the offering of Registrable Securities offered
thereby is not consummated due to factors beyond the control of the Holders of
such Registrable Securities, including without limitation in the context of a
proposed firm commitment underwriting, the fact that the underwriters have
advised the Holders of such Registrable Securities that such Registrable
Securities cannot be sold at a net price equal to or above the net price
specified in the notice to the Company at the time of the request, or (iv) if
the conditions to closing specified in the purchase agreement or underwriting
agreement entered into in connection with such registration are not satisfied
(unless a substantial cause of such conditions to closing not being satisfied
shall be attributable to one or more Holders of Registrable Securities whose
Registrable Securities were included in such registration statement).

                  (g) Selection of Underwriters. If a requested registration
pursuant to this Section 2.1 involves an underwritten offering, the underwriter
or underwriters thereof shall be selected by the Company with the approval of
the Holders of at least 50% of the Registrable Securities to be so registered,
which approval will not be unreasonably withheld.

                  (h) Priority in Requested Registrations. If a requested
registration pursuant to this Section 2.1 involves an underwritten offering, and
the managing underwriter shall advise the Company in writing (with a copy to
each Holder requesting registration) that, in its opinion, the number of
securities requested to be included in such registration exceeds the number
which can be sold in such offering within a price range acceptable to the
Holders of more than 50% of the Registrable Securities requested to be included
in such registration, then the Registrable Securities requested to be registered
pursuant to this Section 2.1 shall be reduced to the number of Registrable
Securities which the Company is so advised can be sold in (or during the time
of) such offering by decreasing the Registrable Securities requested to be
registered (pro rata among the Holders requesting such registration on the basis
of the percentage of the Registrable Securities held by such Holder immediately
prior to the filing of the registration statement with respect to such
registration). Nothing in this Section 2.1(h) shall affect (i) the rights of
Series A Persons requesting registration to include all of the securities
requested to be registered by such Series A Persons in such registration without
reduction prior to the inclusion of any Registrable Securities requested to be
registered hereunder, or (ii) the rights of Series B Persons, Series C Persons,
Series D Persons, Series E Persons, and Warrant Purchasers requesting
registration to include securities in such registration on a pro rata basis with
the Registrable Securities of Holders hereunder in the same manner as described
in Section 2.1(c) hereof.

                  (i) Form S-3. Notwithstanding the other provisions of this
Section 2.1, until the fifth anniversary of the effective date of the Company's
first registration statement under the Securities Act, the Company shall be
required upon the written request of Holder(s) by this Section 2.1 to effect,
and bear all expenses (as determined pursuant to Section 2.1(e) hereof) incurred
in connection with, up to two registrations on Form S-3 (or any successor
similar form) of Registrable Securities during such



                                       5
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period, provided that the Registrable Securities to be registered thereon are
expected to have an aggregate disposition price (before deductions for
underwriting discounts and commissions) of at least $500,000.

                  (j) Notwithstanding anything to the contrary contained herein,
the Company shall not be obligated to prepare and file any other registration
statement pursuant to this Section 2.1 within 180 days of the consummation of an
underwritten public offering of Common Stock pursuant to a registration
statement filed under the Securities Act.

                  2.2 Incidental Registration.

                  (a) Right to Include Registrable Securities. If the Company at
any time prior to the fifth anniversary of the effective date of the Company's
first registration statement under the Securities Act proposes to register any
of its securities under the Securities Act (other than by a registration on Form
S-8, S-4 or any successor similar forms or any other form not available for
registering the Registrable Securities for sale to the public and other than
pursuant to Section 2.1 hereof), whether or not for sale for its own account, it
will each such time, at least 15 days prior to filing the registration
statement, give written notice to all Holders of Registrable Securities of its
intention to do so. Upon the written request of Holders of an aggregate of at
least 25,000 shares (appropriately adjusted for subdivisions and combinations of
shares of Common Stock and dividends on Common Stock payable in shares of Common
Stock hereafter) of Registrable Securities, made within 15 days after the
receipt of any such notice (which request shall specify the Registrable
Securities intended to be disposed of by each such Holder and the intended
method of disposition thereof), the Company will use reasonable efforts to
effect the registration under the Securities Act of all Registrable Securities
which the Company has been so requested to register by the Holders of such
Registrable Securities, to the extent requisite to permit the disposition
(determined pursuant to the provisions of Section 2.1(b) hereof) of the
Registrable Securities so to be registered, provided that if, at any time after
giving written notice of its intention to register any securities and prior to
the effective date of the registration statement filed in connection with such
registration, the Company shall determine for any reason not to register or to
delay registration of such securities, the Company may, at its election, give
written notice of such determination to each Holder of Registrable Securities
and, thereupon, (i) in the case of a determination not to register, shall be
relieved of its obligation to register any Registrable Securities in connection
with such registration (but not from its obligation to pay expenses in
accordance with Section 2.1(e) hereof), without prejudice, however, to the
rights of any Holder or Holders of Registrable Securities entitled to do so to
request that such registration be effected as a registration under Section 2.1
hereof, and (ii) in the case of a determination to delay registering, shall be
permitted to delay registering any Registrable Securities being registered
pursuant to this Section 2.2(a), for the same period as the delay in registering
such other securities. No registration effected under this Section 2.2 shall
relieve the Company of its obligation to effect any registration upon request
under Section 2.1 hereof.

                  (b) Priority in Incidental Registrations. If (i) a
registration pursuant to this Section 2.2 involves an underwritten offering of
the securities so being registered, whether or not for sale for the account of
the Company, to be distributed (on a firm commitment basis) by or through one or
more underwriters of recognized standing, whether or not the Registrable
Securities so requested to be registered for sale for the account of Holders of
Registrable Securities are also to be included in such



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underwritten offering, and (ii) the managing underwriter of such underwritten
offering shall inform the Company and the Holders of the Registrable Securities
requesting such registration by letter of its belief that the number of
securities requested to be included in such registration exceeds the number
which can be sold in (or during the time of) such offering, then the Company may
include in such offering all securities proposed by the Company to be sold for
its own account and may decrease the number of Registrable Securities and other
securities of the Company that persons have requested to be included in such
registration by (a) first decreasing the securities requested to be included in
such registration other than Registrable Securities (pro rata among the persons
requesting such registration on the basis of the number of shares of such
securities held by such person immediately prior to the filing of the
registration statement with respect to such registration) and (b) then, to the
extent necessary, decreasing the Registrable Securities requested to be
registered (pro rata among the Holders requesting such registration on the basis
of the percentage of the Registrable Securities held by such Holders immediately
prior to the filing of the registration statement with respect to such
registration); provided, however, that the rights of Holders hereunder shall be
subject to (i) the right of the Series A Persons requesting inclusion of
securities in such registration to include all of the securities requested to be
registered by such Series A Persons in such registration without reduction prior
to the inclusion of any Registrable Securities requested to be included in such
registration pursuant to this Section 2.2., and (ii) the rights of Series B
Persons, Series C Persons, Series D Persons, Series E Persons, and Warrant
Purchasers requesting registration to include securities in such registration on
a pro rata basis with the Registrable Securities of Holders hereunder in the
same manner as described in Section 2.1(c) hereof.

                  2.3 Registration Procedures. If and whenever the Company is
required to use reasonable efforts to effect the registration of any Registrable
Securities under the Securities Act as provided in Sections 2.1 and 2.2 hereof,
the Company will, subject to the limitations provided herein, as expeditiously
as possible:

                  (a) prepare and (as soon thereafter as possible or in any
         event no later than 60 days after the end of the period within which
         requests for registration may be given to the Company or such longer
         period as the Company shall in good faith require to produce the
         financial statements required in connection with such registration)
         file with the Commission the requisite registration statement to effect
         such registration and thereafter use reasonable efforts to cause such
         registration statement to become effective, provided that the Company
         may discontinue any registration of its securities which are not
         Registrable Securities (and, under the circumstances specified in
         Section 2.2(a) hereof, its securities which are Registrable Securities)
         at any time prior to the effective date of the registration statement
         relating thereto;

                  (b) prepare and file with the Commission such amendments and
         supplements to such 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 disposition of all securities covered by such
         registration statement until such time as all of such securities have
         been disposed of in accordance with the intended methods of disposition
         by the seller or sellers thereof set forth in such registration
         statement; provided, however, that the Company shall not in any event
         be required to keep the registration statement effective for a period
         of more than three months after such registration statement becomes
         effective;


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<PAGE>
                  (c) furnish to each seller of Registrable Securities covered
         by such registration statement such number of conformed copies of such
         registration statement and of each such amendment and supplement
         thereto (in each case including all exhibits), such number of copies of
         the prospectus contained in such registration statement (including each
         preliminary prospectus and any summary prospectus) and any other
         prospectus filed under Rule 424 under the Securities Act, and such
         other documents, as such seller may reasonably request;

                  (d) use reasonable efforts to register or qualify all
         Registrable Securities and other securities covered by such
         registration statement under such other securities or blue sky laws of
         such jurisdictions as each seller thereof shall reasonably request, to
         keep such registration or qualification in effect for so long as such
         registration statement remains in effect (provided, however, that the
         Company shall not in any event be required to keep such registration or
         qualification in effect for a period of more than three months after
         such registration or qualification becomes effective), and take any
         other action which may be reasonably necessary or advisable to enable
         such seller to consummate the disposition in such jurisdictions of the
         securities owned by such seller, except that the Company shall not for
         any such purpose be required to qualify generally to do business as a
         foreign corporation in any jurisdiction wherein it would not but for
         the requirements of this subdivision (d) be obligated to be so
         qualified or to consent to general service of process in any such
         jurisdiction;

                  (e) use reasonable efforts to cause all Registrable Securities
         covered by such registration statement to be registered with or
         approved by such other United States federal or state governmental
         agencies or authorities as may be necessary to enable the seller or
         sellers thereof to consummate the disposition of such Registrable
         Securities;

                  (f) furnish to each seller of Registrable Securities a copy,
         or, upon request, a signed counterpart, addressed to such seller (and
         the underwriters, if any) of

                           (i) an opinion of counsel for the Company, dated the
                  effective date of such registration statement (or, if such
                  registration includes an underwritten public offering, dated
                  the date of the closing under the underwriting agreement), and

                           (ii) a "comfort" letter addressed to the
                  underwriters, dated the effective date of such registration
                  statement (or, if such registration includes an underwritten
                  public offering, dated the date of the closing under the
                  underwriting agreement), signed by the independent public
                  accountants who have audited the Company's financial
                  statements included in such registration statement, covering
                  substantially the same matters with respect to such
                  registration statement (and the prospectus included therein)
                  and, in the case of the accountants' letter, with respect to
                  events subsequent to the date of such financial statements, as
                  are customarily covered in opinions of issuer's counsel and in
                  accountants' letters delivered to the underwriters in
                  underwritten public offerings of securities and, in the case
                  of the accountants' letter, such other financial matters, and,
                  in the case of the legal opinion such other legal matters, as
                  such seller or such Holder (or the underwriters, if any) may
                  reasonably request;


                                       8
<PAGE>
                  (g) notify each seller of Registrable Securities covered by
         such registration statement, at any time when a prospectus relating
         thereto is required to be delivered under the Securities Act, upon
         discovery that, or upon 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 any material fact required to be stated therein or necessary to
         make the statements therein not misleading in the light of the
         circumstances under which they were made, and at the request of any
         such seller, prepare and furnish to such seller a reasonable number of
         copies of a supplement to or an amendment of such prospectus as may be
         necessary so that, as thereafter delivered to the purchasers of such
         securities, such prospectus shall not 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 not misleading in
         the light of the circumstances under which they were made;

               (h) otherwise use reasonable efforts to comply with all
        applicable rules and regulations of the Commission, and make available
        to its security holders, as soon as reasonably practicable, an earnings
        statement covering the period of at least twelve months beginning with
        the first full calendar month after the effective date of such
        registration statement, which earnings statement shall satisfy the
        provisions of Section 11(a) of the Securities Act, and will furnish to
        each such seller, upon request of such seller, prior to the filing
        thereof a copy of any amendment or supplement to such registration
        statement or prospectus and shall not file any such supplement or
        amendment if such seller shall have delivered to the Company an opinion
        of counsel that such amendment or supplement does not comply in all
        material respects with the requirements of the Securities Act or of the
        rules or regulations thereunder;

               (i) provide and cause to be maintained a transfer agent for all
        Registrable Securities covered by such registration statement from and
        after a date not later than the effective date of such registration
        statement;

               (j) use reasonable efforts to list all Registrable Securities
        covered by such registration statement on any securities exchange on
        which the Common Stock is then listed; and

               (k) refrain from making any sale or distribution of its equity
        securities, except pursuant to any employee stock option plan or other
        employee benefit plan and any preexisting agreement for the sale of such
        securities, for at least 90 days after the closing of the public
        offering pursuant to such registration.

                  It shall be a condition precedent to the obligations of the
Company to take any action with respect to registering a Holder's Registrable
Securities pursuant to this Section 2.3 that such seller of Registrable
Securities as to which any registration is being effected furnish the Company in
writing such information regarding such seller, the Registrable Securities and
other securities of the Company held by such seller, and the distribution of
such securities as the Company may from time to time reasonably request in
writing. If a Holder refuses to provide the Company with any of such information
on the grounds that it is not necessary to include such information in the
registration statement, the Company may exclude such Holder's Registrable
Securities from the registration statement if the Company provides such Holder
with an opinion of counsel to the effect that such information must be included
in the registration statement and such Holder thereafter continues to withhold
such information. The deletion of such Holder's Registrable Securities from a
registration



                                       9
<PAGE>
statement shall not affect the registration of the other Registrable Securities
to be included in such registration statement.

                  Each Holder of Registrable Securities agrees by acquisition of
such Registrable Securities that upon receipt of any notice from the Company of
the happening of any event of the kind described in Section 2.3(g), such Holder
will forthwith discontinue such Holder's disposition of Registrable Securities
pursuant to the registration statement relating to such Registrable Securities
until such Holder's receipt of the copies of the supplemented or amended
prospectus contemplated by Section 2.3(g) and, if so directed by the Company,
will deliver to the Company (at the Company's expense) all copies, other than
permanent file copies then in such Holder's possession, of the prospectus
relating to such Registrable Securities current at the time of receipt of such
notice.

                  2.4 Underwritten Offerings.

                  (a) Requested Underwritten Offerings. If requested by the
underwriters for any underwritten offering of Registrable Securities pursuant to
a registration requested under Section 2.1 hereof, the Company will enter into
an underwriting agreement with such underwriters for such offering, the portions
of such agreement that relate to Holders of Registrable Securities being
registered to be reasonably satisfactory in substance and form to each Holder of
Registrable Securities being registered and to contain such representations and
warranties by the Company and such other terms as are generally prevailing in
agreements of this type, including, without limitation, indemnities
substantially to the effect and to the extent provided in Section 2.6 hereof.
Each such Holder of Registrable Securities will cooperate with the Company in
the negotiation of the underwriting agreement and will give consideration to the
reasonable requests of the Company regarding the form thereof, provided that
nothing herein contained shall diminish the foregoing obligations of the
Company. If requested by the underwriters of any underwritten offering pursuant
to a registration under Section 2.1 hereof, each Holder of Registrable
Securities agrees to enter into an agreement with such underwriters not to sell
his or its shares of stock in the Company for a period of time (not to exceed
180 days) after the effectiveness of a registration statement equal to the
period of time which the sellers of securities in such registration, by separate
agreement with the underwriters, have agreed not to sell their shares after the
effectiveness of such registration statement. The Holders of Registrable
Securities to be distributed by such underwriters shall be parties to such
underwriting agreement. Any such Holder shall not be required to make any
representations or warranties to or agreements with the Company or the
underwriters other than representations, warranties or agreements regarding such
Holder, such Holder's Registrable Securities and other securities of the
Company, such Holder's intended method of distribution, and any representations,
warranties or agreements required by law.

                  (b) Incidental Underwritten Offerings. If the Company at any
time proposes to register any of its securities under the Securities Act as
contemplated by Section 2.2 hereof and such securities are to be distributed by
or through one or more underwriters, the Company will, if requested by any
Holder of Registrable Securities as provided in Section 2.2 hereof and subject
to the provisions of Section 2.2(b) hereof, arrange for such underwriters to
include all the Registrable Securities to be offered and sold by such Holder
owning the securities to be distributed by such underwriters. In such event, the
Holders of Registrable Securities to be distributed by such underwriters shall
be parties to the underwriting agreement between the Company and such
underwriters. Any such Holder shall not be required to make any representations
or warranties to or agreements with the Company or the



                                       10
<PAGE>
underwriters other than representations, warranties or agreements regarding such
Holder, such Holder's Registrable Securities or other securities of the Company,
such Holder's intended method of distribution and any representations,
warranties or agreements required by law.

                  2.5 Preparation; Reasonable Investigation. In connection with
the preparation and filing of each registration statement under the Securities
Act pursuant to this Agreement, the Company will give the Holders of Registrable
Securities registered under such registration statement, their underwriters, if
any, and one counsel or firm of counsel and one accountant or firm of
accountants representing all the Holders of Registrable Securities to be
registered under such registration statement, the opportunity to participate in
the preparation of such registration statement, each prospectus included therein
or filed with the Commission, and each amendment thereof or supplement thereto,
and will give each of them such access to its books and records and such
opportunities to discuss the business of the Company with its officers and the
independent public accountants who have certified its financial statements as
shall be necessary, in the opinion of such Holders' and such underwriters'
respective counsel, to conduct a reasonable investigation within the meaning of
the Securities Act.

                  2.6 Indemnification.

                  (a) Indemnification by the Company. In the event any
Registrable Securities are included in a registration statement under this
Section 2, to the extent permitted by law, the Company will, and hereby does,
indemnify and hold harmless the seller of any Registrable Securities covered by
such registration statement, its directors and officers, each other person who
participates as an underwriter in the offering or sale of such securities and
each other person, if any, who controls such seller or any such underwriter
within the meaning of the Securities Act, against any losses, claims, damages or
liabilities, joint or several, to which such seller or any such director or
officer or underwriter or controlling person may become subject under the
Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions or proceedings, whether commenced or threatened, in
respect thereof) arise out of or are based upon any untrue statement or alleged
untrue statement of any material fact contained in any registration statement
under which such securities were registered under the Securities Act, any
preliminary prospectus, final prospectus or summary prospectus contained
therein, or any amendment or supplement thereto, or any omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, and the Company will
reimburse such seller and each such director, officer, underwriter and
controlling person for any legal or any other expenses reasonably incurred by
them in connection with investigating or defending any such loss, claim,
liability, action or proceeding; provided that the Company shall not be liable
in any such case to the extent that any such loss, claim, damage, liability (or
action or proceeding in respect thereof) or expense arises out of or is based
upon an untrue statement or alleged untrue statement or omission or alleged
omission made in such registration statement, any such preliminary prospectus,
final prospectus, summary prospectus, amendment or supplement in reliance upon
and in conformity with written information furnished to the Company by such
seller expressly for use in the preparation thereof, and provided further that
the Company shall not be liable to any person who participates as an underwriter
in the offering or sale of Registrable Securities or any other Person, if any,
who controls such underwriter within the meaning of the Securities Act, in any
such case to the extent that any such loss, claim, damage, liability (or action
or proceeding in respect thereof) or expense arises out of such person's failure
to send or give a



                                       11
<PAGE>
copy of the final prospectus, as the same may be then supplemented or amended,
to the person asserting an untrue statement or alleged untrue statement or
omission or alleged omission at or prior to the written confirmation of the sale
of the Registrable Securities to such person if such statement or omission was
corrected in such final prospectus. Such indemnity shall remain in full force
and effect regardless of any investigation made by or on behalf of such seller
or any such director, officer, underwriter or controlling person and shall
survive the transfer of such securities by such seller.

                  (b) Indemnification by the Sellers. The Company may require,
as a condition to including any Registrable Securities in any registration
statement filed pursuant to Section 2.3 hereof, that the Company shall have
received an undertaking satisfactory to it from the prospective seller of such
securities, to indemnify and hold harmless (in the same manner and to the same
extent as set forth in subdivision (a) of this Section 2.6) each underwriter,
each person who controls such underwriter within the meaning of the Securities
Act, the Company, each director of the Company, each officer of the Company and
each other person, if any, who controls the Company within the meaning of the
Securities Act, with respect to any statement or alleged statement in or
omission or alleged omission from such registration statement, any preliminary
prospectus, final prospectus or summary prospectus contained therein, or any
amendment or supplement thereto, if such statement or alleged statement or
omission or alleged omission was made in reliance upon and in strict conformity
with written information furnished to the Company by such seller expressly for
use in the preparation of such registration statement, preliminary prospectus,
final prospectus, summary prospectus, amendment or supplement; provided that
such prospective seller shall not be liable to any person who participates as an
underwriter in the offering or sale of Registrable Securities or any other
person, if any, who controls such underwriter within the meaning of the
Securities Act, in any such case to the extent that any such loss, claim,
damage, liability (or action or proceeding in respect thereof) or expense arises
out of such person's failure to send or give a copy of the final prospectus, as
the same may be then supplemented or amended, to the person asserting an untrue
statement or alleged untrue statement or omission or alleged omission at or
prior to the written confirmation of the sale of Registrable Securities to such
person if such statement or omission was corrected in such final prospectus.
Such indemnity shall remain in full force and effect, regardless of any
investigation made by or on behalf of any underwriter, the Company or any such
director, officer or controlling person and shall survive the transfer of such
securities by such seller. In no event shall the liability of any selling holder
of Registrable Securities under this Section 2.6(b) be greater in amount than
the dollar amount of the proceeds received by such holder upon the sale of the
Registrable Securities giving rise to such indemnification obligation.

                  (c) Notices of Claims, etc. Promptly after receipt by an
indemnified party of notice of the commencement of any action or proceeding
involving a claim referred to in the preceding subdivisions of this Section 2.6,
as a condition to the obligations of the indemnifying party with respect
thereto, such indemnified party will, if a claim in respect thereof is to be
made against an indemnifying party, give written notice to the latter of the
commencement of such action; provided that the failure of any indemnified party
to give notice as provided herein shall not relieve the indemnifying party of
its obligations under the preceding subdivisions of this Section 2.6, except to
the extent that the indemnifying party is actually prejudiced by such failure to
give notice. In case any such action is brought against an indemnified party,
the indemnifying party shall be entitled to participate in and to assume the
defense thereof, jointly with any other indemnifying party similarly notified to
the extent that it may wish, with counsel reasonably satisfactory to such
indemnified party, and after notice from the indemnifying party to such
indemnified party of its election so to assume the



                                       12
<PAGE>
defense thereof, the indemnifying party shall not be liable to such indemnified
party for any legal or other expenses subsequently incurred by the latter in
connection with the defense thereof other than reasonable costs of
investigation. No indemnifying party shall, without the consent of the
indemnified party, consent to entry of any judgment or enter into any settlement
which does not include as an unconditional term thereof the giving by the
claimant or plaintiff to such indemnified party of a release from all liability
in respect to such claim or litigation.

                  (d) Other Indemnification. Indemnification similar to that
specified in the preceding subdivisions of this Section 2.6 (with appropriate
modifications) shall be given by the Company and each seller of Registrable
Securities with respect to any required registration or other qualification of
securities under any federal or state law or regulation of any governmental
authority other than the Securities Act.

                  (e) Indemnification Payments. The indemnification required by
this Section 2.6 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
expense, loss, damage or liability is incurred.

                  (f) Contribution. If the indemnification provided for in this
Section 2.6 from the indemnifying party is unavailable to an indemnified party
hereunder in respect of any losses, claims, damages, liabilities or expenses
referred to therein, then the indemnifying party, in lieu of indemnifying such
indemnified party, shall contribute to the amount paid or payable by such
indemnified party as a result of such loss, claims, damages, liabilities or
expenses in such proportion as is appropriate to reflect the relative fault of
the indemnifying party and indemnified parties in connection with the actions
which resulted in such losses, claims, damages, liabilities or expenses, as well
as any other relevant equitable considerations. The relative fault of such
indemnifying party and indemnified parties shall be determined by reference to,
among other things, whether any action in question, including any untrue
statement of material fact or omission or alleged omission to state a material
fact, has been made by, or relates to information supplied by, such indemnifying
party or indemnified parties, and the parties' relative intent, knowledge,
access to information and opportunity to correct or prevent such action. The
amount paid or payable by a party as a result of the losses, claims, damages,
liabilities and expenses referred to above shall be deemed to include, subject
to the limitations set forth in Section 2.6(c) hereof, any legal or other fees
or expenses reasonably incurred by such party in connection with any
investigation or proceeding.

                  The Company and, as a condition to the registration of any of
their Registrable Securities, the Holders agree that it would not be just and
equitable if contribution pursuant to this Section 2.6(f) 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 the immediately preceding
paragraph. Notwithstanding the provisions of this Section 2.6(f), no underwriter
shall be required to contribute any amount in excess of the amount by which the
aggregate total price at which the Registrable Securities underwritten by it and
distributed to the public were offered to the public exceeds the amount of any
damages which such underwriter has otherwise been required to pay by reason of
such untrue or alleged untrue statement or omission or alleged omission, and no
selling Holder shall be required to contribute any amount in excess of the
amount by which the aggregate total price at which the Registrable Securities of
such selling Holder were offered to the public exceeds the amount of any damages
which such selling Holder has otherwise been required to pay by reason of such
untrue or alleged untrue statement or omission. No person guilty of fraudulent
misrepresentation (within the



                                       13
<PAGE>
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.

                  2.7 Reporting Requirements Under Exchange Act. When it is
first legally required to do so, the Company shall register its Common Stock
under Section 12 of the Exchange Act (as hereinafter defined) and shall keep
effective such registration and shall timely file such information, documents
and reports as the Commission may require or prescribe under Section 13 of the
Exchange Act. From and after the effective date of the first registration
statement filed by the Company under the Securities Act, the Company shall
(whether or not it shall then be required to do so) timely file such
information, documents and reports which a corporation, partnership or other
entity subject to Section 13 or 15(d) (whichever is applicable) of the Exchange
Act is required to file.

                  Immediately upon becoming subject to the reporting
requirements of either Section 13 or 15(d) of the Exchange Act, the Company
shall forthwith upon request furnish any Holder of Registrable Securities (i) a
written statement by the Company that it has complied with such reporting
requirements, (ii) a copy of the most recent annual or quarterly report of the
Company, and (iii) such other reports and documents filed by the Company with
the Commission as such Holder may reasonably request in availing itself of an
exemption for the sale of Registrable Securities without registration under the
Securities Act. The Company acknowledges and agrees that the purposes of the
requirements contained in this Section 2.7 are (a) to enable any such Holder to
comply with the current public information requirement contained in Paragraph
(c) of Rule 144 should such Holder ever wish to dispose of any of the securities
of the Company acquired by it without registration under the Securities Act in
reliance upon Rule 144 (or any other similar exemptive provision) and (b) to
qualify the Company for the use of registration statements on Form S-3. In
addition, the Company shall take such other measures and file such other
information, documents and reports, as shall hereafter be required by the
Commission as a condition to the availability of Rule 144 under the Securities
Act (or any similar exemptive provision hereafter in effect) and the use of Form
S-3. The Company also covenants to use reasonable efforts, to the extent that it
is reasonably within its power to do so, to qualify for the use of Form S-3.

                  2.8 Stockholder Information. The Company may require each
Holder of Registrable Securities as to which any registration is to be effected
pursuant to this Section 2 to furnish the Company such information in writing
with respect to such Holder and the distribution of such Registrable Securities
as the Company may from time to time reasonably request in writing and as shall
be required by law or by the Commission in connection therewith.

                  2.9 Forms. All references in this Agreement to particular
forms of registration statements are intended to include, and shall be deemed to
include, references to all successor forms which are intended to replace, or to
apply to similar transactions as, the forms herein referenced.

                  2.10 Transfer of Registration Rights. The registration rights
granted to the Holders of Registrable Securities under this Section 2 may not be
transferred without the prior written consent of the Company; provided that such
registration rights may be transferred, in whole or in part, without such prior
written consent in connection with the transfer of Registrable Securities to (i)
an affiliate (defined as any person which directly or indirectly controls, is
controlled by, or is under common control with such Purchaser) of the Purchaser
or (ii) to an immediate or remote transferee of the Purchaser who after such
transfer is the Holder of at least 50% of the number of Registrable Securities


                                       14
<PAGE>
purchased by such original Purchaser (appropriately adjusted for subdivisions
and combinations of shares of Common Stock and dividends on Common Stock payable
in shares of Common Stock subsequent to the date of this Agreement).

                  3. MISCELLANEOUS.

                  3.1 GOVERNING LAW. THIS AGREEMENT SHALL BE GOVERNED IN ALL
RESPECTS BY THE LAWS OF THE STATE OF TEXAS WITHOUT REGARD TO THE CONFLICT OF
LAWS PRINCIPLES THEREOF.

                  3.2 Successors and Assigns. Except as otherwise provided
herein, the provisions hereof shall inure to the benefit of, and be binding
upon, the successors and assigns of the parties hereto.

                  3.3. Amendment. Except as expressly provided herein, this
Agreement, or any provision hereof, may be amended, waived, discharged or
terminated upon the written consent of the Company and the Holders holding at
least two-thirds (2/3) of the then outstanding Registrable Securities.

                  3.4 Notices, etc. All notices and other communications
required or permitted hereunder shall be in writing and shall be mailed by first
class mail, postage prepaid, or otherwise delivered by hand or by messenger
including Federal Express or similar courier service, addressed (a) if to the
Purchaser at 5-11 Nihonbashi Honcho 2-chome, chuo-ku, Tokyo 103-0023, Japan or
at such other address as such party shall have furnished to the Company in
writing, or (b) if to the Company at 8122 Datapoint Drive, Suite 1250, San
Antonio, Texas 78229, Attn: Chief Executive Officer, or at such other address as
the Company shall have furnished to the other parties hereto.

                  Each such notice or other communication shall for all purposes
of this Agreement be treated as effective upon receipt.

                  3.5 Delays or Omissions. Except as expressly provided herein,
no delay or omission to exercise any right, power or remedy accruing to any
party to this Agreement shall impair any such right, power or remedy of such
party nor shall it be construed to be a waiver of any such breach or default, or
an acquiescence therein, or of or in any similar breach or default thereafter
occurring; nor shall any waiver or any single breach or default be deemed a
waiver of any other breach or default theretofore or thereafter occurring. Any
waiver, permit, consent or approval of any kind or character on the part of any
party of any breach or default under this Agreement, or any waiver on the part
of any party of any provisions or conditions of this Agreement, must be in
writing and shall be effective only to the extent specifically set forth in such
writing. All remedies, either under this Agreement or by law or otherwise
afforded to any party to this Agreement, shall be cumulative and not
alternative.

                  3.6 Severability. In the event that any provision of this
Agreement becomes or is declared by a court of competent jurisdiction to be
illegal, unenforceable or void, this Agreement shall continue in full force and
effect without said provision.

                  3.7 Titles and Subtitles. The titles and subtitles used in
this Agreement are used for convenience only and are not considered in
construing or interpreting this Agreement.


                                       15
<PAGE>
                  IN WITNESS WHEREOF, this Agreement has been executed by the
undersigned parties effective upon the date first set forth above.

                                    "COMPANY"

                                    BIONUMERIK PHARMACEUTICALS, INC.

                                    By: /s/ FREDERICK H. HAUSHEER
                                        ----------------------------------------

                                    Title: Chairman and Chief Executive Officer
                                           -------------------------------------


                                    "PURCHASER"

                                    GRELAN PHARMACEUTICAL CO., LTD.

                                    By: /s/ H. KANAZAWA
                                        ----------------------------------------

                                    Title: President and Chief Executive Officer
                                           -------------------------------------





                                       16