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                                                                     EXHIBIT 4.5

REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (the" Agreement") is executed as of the 10th
day of July, 1996 by BioNumerik Pharmaceuticals, Inc., a Texas corporation (the
"Company") and Grelan Pharmaceutical Co., Ltd., a Japanese corporation ("Grelan"
or the "Purchaser").

WITNESSETH:

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 D Convertible Preferred Stock, par value $.01
per share, of the Company.

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"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 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
registrations 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.

"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.

2. Registration of Registrable Securities.

2.1 Registration on Request.

(a) Request. Subject to the limitations provided herein, commencing on December
31, 1998, 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

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(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
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 and Series C
Persons requesting registration pursuant to the Series B Registration Rights
Agreement and/or the Series C Registration Rights Agreement (whether pursuant to
"demand" or "piggyback" registration rights) to include securities in such
registration on a pro rata basis with

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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 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 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 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.

(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

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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 and Series C Persons 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 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.

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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 an 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) Prior 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 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

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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 and Series C Persons 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;

(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;

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(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;

(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

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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 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 23(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

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contemplated by Section 23(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 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.

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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 counselor 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 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

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<PAGE>

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

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<PAGE>

indemnified party of its election so to assume the 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.

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<PAGE>

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 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

                                       14
<PAGE>

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
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 CONFLI CT OF LA WS 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 4-3
Sakaecho 3-chome, Hamura-City, Tokyo 205, 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

                                       15
<PAGE>

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.

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: Chief Executive Officer

"PURCHASER"

Grelan Pharmaceutical Co., Ltd.

By: \s\ H. KANAZAWA
   ---------------------------------------
Title: C.O.O. and Vice President-Director

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