Document:

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                                                                   EXHIBIT 10.23
                          SECURITIES PURCHASE AGREEMENT

         This Securities Purchase Agreement (the "Agreement") is made as of the
13th day of December, 2001, by and between ISTA Pharmaceuticals, Inc. (the
"Company"), a Delaware corporation, with its principal place of business at
15279 Alton Parkway #100, Irvine, California 92618, and Otsuka Pharmaceutical
Co., Ltd., a corporation organized under the laws of Japan, with a principal
place of business at 2-9, Kanka Tsukasa-cho, Chiyoda-ku, Tokyo 101-8535, Japan
(the "Purchaser").

                                    RECITALS

         A. The Purchaser and the Company have of even date herewith entered
into a License Agreement and a Supply Agreement (collectively, the "License
Agreements") and the obligations in the License Agreements are conditioned upon
the execution and delivery of this Agreement.

         B. The Company has authorized the issuance and sale to the Purchaser,
pursuant to this Agreement, of an aggregate of up to $4,000,000 of shares of the
Company's Common Stock, par value $.001 per share (the "Common Stock").

         B. The Purchaser desire to purchase and the Company desires to issue
and sell shares of Common Stock on the terms and subject to the conditions set
forth herein.

                                    AGREEMENT

         NOW, THEREFORE, in consideration of the foregoing premises, the mutual
covenants herein contained and other good and valuable consideration the receipt
and sufficiency of which is hereby acknowledged, the parties hereto, intending
to be legally bound, hereby agree as follows:

         SECTION 1. Commitment to Purchase.

                  1.01 Number of Shares. Upon the basis of the representations
and warranties, and subject to the terms and conditions contained herein, the
Company agrees to issue and sell to the Purchaser and the Purchaser agrees to
purchase from the Company, at the Closing Date (as defined below), 845,665
shares of Common Stock (the "Shares") at an aggregate purchase price of USD
$3,999,995.45.

                  1.02 Purchase Price. The Shares will be sold to the Purchaser
at a price of $4.73 per share.

         SECTION 2. The Closing.

                  2.01 Closing Date. The closing of the purchase and sale of the
Shares (the "Closing") shall take place at the offices of Wilson Sonsini
Goodrich & Rosati, 650 Page Mill Road, Palo Alto, California ten days after the
date hereof, or at such other location and on such other date
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as the Company and the Purchaser shall mutually agree. The date and time of the
Closing are referred to herein as the "Closing Date."

                  2.02 Payment. At the Closing, Purchaser shall deliver to the
Company (i) the purchase price for the Shares being purchased by the Purchaser
by check or by wire transfer of immediately available funds to an account
designated by the Company at the Closing and (ii) the documents set forth in
Section 6.02 of this Agreement.

                  2.03 Certificate. At the Closing, the Company shall deliver or
cause to be delivered to the Purchaser (i) a certificate representing the Shares
purchased by the Purchaser, in definitive form and registered in the Purchaser's
name or such other name as such Purchaser shall request at least two business
days prior to the Closing Date and (ii) the documents set forth in Section 6.01
of this Agreement.

         SECTION 3. Representations and Warranties of the Company. Except as set
forth on a Schedule of Exceptions annexed hereto as Exhibit B, the Company
hereby represents and warrants to the Purchaser on the date hereof and as of the
Closing Date as follows:

                  3.01 Organization and Qualification. The Company is a
corporation duly organized, validly existing and in good standing under the laws
of the State of Delaware. The Company does not own, directly or indirectly, any
shares of stock or any other equity or long-term debt securities of any
corporation or have any equity interest in any firm, partnership, joint venture,
association or other entity, except for the Company's interest in Visonex Pte.
Ltd., a wholly-owned subsidiary incorporated in Singapore. The Company has the
power and authority, corporate or otherwise, as appropriate, to own, lease and
operate its properties and to conduct its business as now conducted and to enter
into and perform its obligations under this Agreement and the Registration
Rights Agreement, in the form annexed hereto as Exhibit A (the "Registration
Rights Agreement"). The Company is duly qualified as a foreign corporation and
is in good standing in each jurisdiction in which such qualification is
required, whether by reason of the ownership or leasing of property or the
conduct of business, except where the failure to so qualify would not
individually or in the aggregate have a material adverse effect on the condition
(financial or otherwise), earnings, properties, business, prospects or results
of operations of the Company (a "Material Adverse Effect").

                  3.02 Authorized Capital Stock. As of the date hereof, the
authorized capital stock of the Company consists of 100,000,000 shares of Common
Stock, $0.001 par value, and 5,000,000 shares of Preferred Stock, $0.001 par
value. As of the date hereof, approximately 15,600,259 shares of Common Stock
and no shares of Preferred Stock will be validly issued and outstanding, and
each outstanding share of Common Stock is fully paid and nonassessable. The
Company has reserved approximately 77,741 shares of Common Stock for issuance
pursuant to the Company's 2000 Stock Plan and has unexercised options to
purchase 2,563,900 shares of Common Stock outstanding as of the date hereof. The
designations, powers, preferences, rights, qualifications, limitations and
restrictions in respect of each class and series of authorized capital stock of
the Company are as set forth in the Company's certificate of incorporation, a
true and correct copy of which, as amended to date, has previously been provided
to the Purchaser, and there are no additional agreements specifying any rights
with respect thereto. The issued and outstanding shares of Common Stock

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were not issued in violation of or are not otherwise subject to any preemptive
or other similar rights or other rights to subscribe for or purchase securities,
and conform to the description thereof contained in the reports (the "`34 Act
Reports") filed by the Company with the Securities and Exchange Commission (the
"Commission") since January 1, 2001 pursuant to the Securities Exchange Act of
1934, as amended (the "Exchange Act"). Except for options issued under the
Company's stock plans, the Company does not have outstanding any options or
warrants to purchase, or any preemptive rights or other rights to subscribe for
or to purchase, any securities or obligations convertible into, or any contracts
or commitments to issue or sell, shares of its capital stock or any shares of
capital stock of any subsidiary and there is no commitment, plan or arrangement
to issue, any securities or obligations convertible into any shares of capital
stock of the Company or any such options, rights convertible securities or
obligations. The description of the Company's capital stock, stock bonus and
other stock plans or arrangements and the options or other rights granted and
exercised thereunder, contained in the `34 Act Reports accurately and fairly
presents the information required to be shown with respect to such capital
stock, plans, arrangements, options and rights.

                  3.03 Issuance, Sale and Delivery of the Shares. The Shares
have been duly authorized and, when issued, delivered and paid for in the manner
set forth in this Agreement, will be duly authorized, validly issued, fully paid
and nonassessable. No preemptive rights or other rights (which have not been
waived) to subscribe for or purchase exist with respect to the issuance and sale
of the Shares by the Company pursuant to this Agreement. No stockholder of the
Company has any right to request or require the Company to register the sale of
any shares owned by such stockholder under the Securities Act of 1933, as
amended (the "Securities Act"), except for certain stockholders who have
registration rights pursuant to the Company's March 29, 2000 Amended and
Restated Investors Right Agreement (the "Investor Rights Agreement"). Subject to
the satisfaction of the conditions set forth in Section 6.02, no further
approval or authority of the stockholders or the Board of Directors of the
Company will be required for the issuance and sale of the Shares as contemplated
herein, or registration of the Shares under the Registration Rights Agreement.
Without limiting the foregoing, no holders of outstanding shares of capital
stock of the Company has any right, including, but not limited to, those rights
set forth in the Investor Rights Agreement, which has not been waived to require
the Company to register the offer or sale of any securities owned by such holder
in the registration contemplated by the Registration Rights Agreement.

                  3.04 Due Execution, Delivery and Performance of this
Agreement. The Company has full legal right, corporate power and authority to
enter into this Agreement and the Registration Rights Agreement and to perform
the transactions contemplated hereby and thereby. Each of this Agreement and the
Registration Rights Agreement has been duly authorized, executed and delivered
by the Company. The execution, delivery and performance of this Agreement and
the Registration Rights Agreement by the Company and the consummation of the
transactions contemplated hereby and thereby will not violate any provision of
the organizational documents of the Company and will not result in the creation
of any lien, charge, security interest or encumbrance upon any assets or
property of the Company pursuant to the terms or provisions of, or will not
conflict with, result in the breach or violation of, or constitute, either by
itself or upon notice or the passage of time or both, a default under any
agreement, mortgage, deed of trust, lease, franchise, license, indenture, permit
or other instrument to which the Company is a party or by which the Company or
any of its assets or properties may be bound or affected or, to the Company's
knowledge, and subject to satisfaction of

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the conditions set forth in Section 6.02, any statute or any authorization,
judgment, decree, order, rule or regulation of any court or any regulatory body,
administrative agency or other governmental body applicable to the Company or
any of its properties. No consent, approval, authorization or other order of any
court, regulatory body, administrative agency or other governmental body is
required for the execution, delivery and performance of this Agreement or the
Registration Rights Agreement or the consummation of the transactions
contemplated hereby or thereby, except for compliance with Blue Sky laws and
federal securities laws applicable to the offering and registration for resale
of the Shares and compliance with the rules and regulations of the securities
exchange or trading market on which the Common Stock is listed. Upon the
execution and delivery, and assuming the valid execution of this Agreement and
the Registration Rights Agreement by the Purchaser, each of this Agreement and
the Registration Rights Agreement will constitute valid and binding obligations
of the Company, enforceable against the Company in accordance with their
respective terms, except as enforceability may be limited by applicable
bankruptcy, insolvency, reorganization, moratorium or similar laws affecting
creditors' rights generally and except as enforceability may be subject to
general principles of equity (regardless of whether such enforceability is
considered in a proceeding in equity or at law).

                  3.05 Financials. The Company's financial statements (including
all notes and schedules thereto) included in the `34 Act Reports present fairly
the financial position, the results of operations, the statements of cash flows
and the statements of stockholders' equity and the other information purported
to be shown therein of the Company at the respective dates and for the
respective periods to which they apply (subject, in the case of unaudited
statements, to normal year end audit adjustments and the absence of footnotes)
and such financial statements have been prepared in conformity with generally
accepted accounting principles, consistently applied throughout the periods
involved (except as may be indicated in the notes thereto). Since the date of
the most recent financial statements included in the "34 Act Reports, there has
not been: (i) any event or condition of any character that, either individually
or cumatively, has or would have a Material Adverse Effect or (ii) any sale,
assignment or transfer of any patents, trademarks, trade secrets or other
intangible assets of the Company.

                  3.06 Contracts. The contracts described in the `34 Act Reports
as being in effect on the date hereof, are in full force and effect on the date
hereof, and the Company is not, nor to the Company's knowledge, is any other
party in breach of or default under any written agreement which would have a
Material Adverse Effect.

                  3.07 Compliance With Laws; No Actions. To its knowledge, the
Company is not in violation of any applicable statute, rule, regulation, order
or restriction of any domestic or foreign government or any instrumentality or
agency thereof in respect of the conduct of its business or the ownership of its
properties which violation would result in a Material Adverse Change. There are
no legal or governmental actions, suits or proceedings pending or, to the
Company's knowledge, threatened to which the Company is or may be a party or of
which property owned or leased by the Company is or may be the subject. The
Company is not a party to or subject to the provisions of any material
injunction, judgment, decree or order of any court, regulatory body
administrative agency or other governmental body.

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                  3.08 Finders' Fees. There is no investment banker, broker,
finder or other intermediary which has been retained by or is authorized to act
on behalf of the Company who might be entitled to any fee or commission from the
Company or any of its affiliates upon consummation of the transactions
contemplated by this Agreement.

                  3.09 Commission Reports. The Company has filed in a timely
manner all documents that the Company was required to file with the Commission
under the `34 Act and all rules and regulations thereunder since the date on
which the Company became subject to such reporting requirements. As of their
respective filing dates, all documents filed by the Company with the Commission
complied in all material respects with the requirements of the `34 Act or the
Securities Act, as applicable and all rules and regulations thereunder.

                  3.10 Taxes. The Company and its subsidiaries have filed all
required federal, state and foreign income and franchise tax returns and have
paid or accrued all taxes shown as due thereon, and the Company has no knowledge
of any tax deficiency which has been or might be asserted or threatened against
the Company or its subsidiaries which would have a Material Adverse Effect.

                  3.11 Insurance. Each of the Company and its subsidiaries
maintains insurance of the types and in the amounts generally deemed adequate
for its business, including, but not limited to, insurance covering all real and
personal property owned or leased by the Company and its subsidiaries against
theft, damage, destruction, acts of vandalism and all other risks customarily
insured against, all of which insurance is in full force and effect.

                  3.12 Intellectual Property. There are no claims pending or, to
the Company's knowledge, threatened that the Company or any of its subsidiaries
is infringing (including with respect to the manufacture, use or sale by the
Company or any of its subsidiaries of their respective products) upon any
patent, patent application, trademark, trademark rights, trade names, trade name
rights, copyrights, technical know-how and other proprietary intellectual
property rights (the "Intellectual Property Rights") of a third party, and the
Company has no reason to believe that the past or current business activities of
the Company or its subsidiaries are reasonably likely to give rise to any such
claim(s). To the Company's knowledge, no third party is infringing upon any
material Intellectual Property Right of the Company.

                  3.13 Offering Valid. Assuming the accuracy of the
representations and warranties of the Purchaser contained in Section 4 hereof,
the offer, sale and issuance of the Shares will be exempt from the registration
requirements of the Securities Act, and will have been registered or qualified
(or are exempt from registration and qualification) under the registration,
permit or qualification requirements of all applicable state securities laws.

                  3.14 Disclosure. Neither this Agreement nor any exhibit or
other document delivered in connection herewith contains an untrue statement of
a material fact or omits a material fact necessary to make the statements
contained herein or therein, in the light of the circumstances under which they
were made, not misleading. None of the statements, documents, certificates or
other items supplied by the Company at the Closing shall contain an untrue
statement of a material fact or omit a material fact necessary to make the
statements contained therein, in light of the

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circumstances under which they are made, not misleading. There is no fact which
the Company has not disclosed to the Purchaser and which is known to the Company
(other than facts known to the general public or generally known in the
Company's industry) which would cause a Material Adverse Effect. The Company has
supplied the Purchaser with all written information previously requested by it
in writing.

         SECTION 4. Representations and Warranties of the Purchaser. The
Purchaser hereby represents and warrants to the Company on the date hereof and
as of the Closing Date as follows:

                  4.01 Private Placement.

                           (a) Purchaser understands that the offering and sale
of the Shares is intended to be exempt from registration under the Securities
Act.

                           (b) Purchaser represents and warrants that it is
acquiring the Shares to be purchased by it pursuant to this Agreement for
investment for Purchaser's own account and not with a view to the resale or
distribution of such Shares or any interest therein other than in a transaction
that is registered or exempt from registration under the Securities Act.

                           (c) Purchaser represents and warrants that it is an
"accredited investor" as such term is defined in Regulation D under the
Securities Act.

                           (d) Purchaser represents and warrants that it (either
alone or together with its advisors) has sufficient knowledge and experience in
financial and business matters so as to be capable of evaluating the merits and
risks of its investment in the Shares, and is capable of bearing the economic
risks of such investment, including a complete loss of its investment in the
Shares to be purchased by it hereunder.

                           (e) Purchaser has been given the opportunity to ask
questions of, and receive answers from, the Company regarding the Company, the
terms and conditions of the Shares and related matters, and has been furnished
with the information it deems necessary or desirable to evaluate the merits and
risks of its acquisition of the Shares.

                           (f) Purchaser understands that the Shares that it is
purchasing are characterized as "restricted securities" under the Securities Act
inasmuch as they are being acquired from the Company in a transaction not
involving a public offering and that under the Securities Act and applicable
regulations, such Shares may be resold without registration under the Securities
Act only in certain limited circumstances. It is understood that the
certificates delivered at Closing evidencing the Shares will bear a restrictive
legend.

                           (g) Purchaser has, in connection with its decision to
purchase the Shares, relied solely upon the `34 Act Reports and the
representations and warranties of the Company contained in this Agreement, the
Registration Rights Agreement and the License Agreements.

                  4.02 Additional Representations of Foreign Purchaser If the
Purchaser does not reside in and is not a citizen of the United States, for the
purpose of this Section 4, the Purchaser shall be deemed a "Foreign Purchaser"
and the Purchaser represents, warrants and covenants to the

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Company, in addition to the other representations, warranties and covenants set
forth in this Section 4, to the following, but only in the event, and to the
extent, that the Purchaser seeks to rely upon the provisions of Regulation S for
the resale of the Shares:

                           (a) Neither the Foreign Purchaser nor any person for
the account of whom such Foreign Purchaser is acting, including the estate of
any such person, a trust of which any such person is a beneficiary, or a
corporation, partnership, trust or other entity organized under the laws of the
United States of America, is a citizen or resident of the United States of
America (a "U.S. Person").

                           (b) Such Foreign Purchaser will not sell, transfer or
otherwise dispose of the Shares for the applicable restricted period as set
forth in Regulation S, and such Foreign Purchaser will not thereafter sell or
otherwise transfer the Shares and any securities issued upon conversion or
exercise thereof to a U.S. Person unless the Company has received an opinion of
counsel, satisfactory to the Company, that such transfer will not be in
violation of the Securities Act or any applicable state securities laws.

                           (c) The Foreign Purchaser understands that the
Company will not allow any transfer or other disposition of the Shares and any
securities issued upon conversion or exercise thereof unless the proposed
transferee shall have executed an instrument containing the representations set
forth in the foregoing paragraphs (a) and (b) of this section or the Company
shall have received an opinion of counsel satisfactory to the Company to the
effect that such proposed transfer would not be in violation of the Securities
Act or any applicable state securities law.

                  4.03 Finders' Fees. There is no investment banker, broker,
finder or other intermediary which has been retained by or is authorized to act
on behalf of the Company or Purchaser who might be entitled to any fee or
commission from the Company or any of its affiliates upon consummation of the
transactions contemplated by this Agreement.

         SECTION 5. Additional Agreements and Covenants of the Company and the
Purchaser.

                  5.01 Further Assurances. The Company and the Purchaser agree
to execute and deliver such documents, certificates, agreements and other
writings and to take such other actions as may be reasonably necessary or
desirable in order to consummate or implement expeditiously the transactions
contemplated by this Agreement and the Registration Rights Agreement.

                  5.02 Public Announcements. The Company and the Purchaser shall
consult with each other before issuing any press release or making any public
statement with respect to this Agreement or the transactions contemplated hereby
and, except as may be required by applicable law or any listing agreement with
any national securities exchange or trading market, will not issue any such
press release or make any such public statement prior to such consultation.

         SECTION 6. Closing Deliveries.

                  6.01 Conditions to the Purchaser's Obligations. The obligation
of the Purchaser to consummate the transactions contemplated by this Agreement
shall be subject to the delivery of the fulfillment prior to or at the Closing
of the following conditions:

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                           (a) The representations and warranties of the Company
contained in Section 3 shall be true on and as of the Closing in all material
respects with the same effect as though such representations and warranties had
been made on and as of the date of such Closing, except for those
representations and warranties which address matters only as of a particular
date, which shall remain true and correct as of such particular date and except
where the failure to be true and correct will not have a Material Adverse Effect
on the Company.

                           (b) The Company shall have performed and complied
with all agreements, obligations and conditions contained in this Agreement that
are required to be performed or complied with by it on or before the Closing.

                           (c) The Company shall have obtained any and all
consents, permits and waivers necessary or appropriate for consummation of the
transactions contemplated by this Agreement and the Registration Rights
Agreement (except for such as may be properly obtained subsequent to the
Closing).

                           (d) The Company shall have executed and delivered the
License Agreements.

                           (e) The Company shall have executed and delivered the
Registration Rights Agreement.

                           (f) The Company shall have delivered the following
closing documents in form and substance reasonably acceptable to the Purchaser's
counsel:

                                    (i) a copy of the resolutions of the
Company's Board of Directors authorizing (A) the execution, delivery and
consummation of this Agreement, the Registration Rights Agreement, and the
License Agreements and (B) transactions contemplated hereby and thereby; and

                                    (ii) a certificate of the President of the
Company, dated the Closing Date, certifying that the conditions specified in
this Section 6.01 have been fulfilled and that as of the Closing Date, there has
not been no Material Adverse Effect.

                           (g) All corporate and other proceedings in connection
with the transactions contemplated at the Closing and all documents incident
thereto shall be reasonably satisfactory in form and substance to Purchaser's
counsel, and Purchaser's counsel shall have received all such counterpart
originals or certified or other copies of such documents as they may reasonably
request.

                  6.02 Conditions to the Obligations of the Company. The
obligation of the Company to consummate the transactions contemplated by this
Agreement shall be subject to the fulfillment at or prior to the Closing of the
following conditions:

                           (a) The representations and warranties of the
Purchaser contained in Section 4 shall be true on and as of the Closing in all
material respects with the same effect as though such representations and
warranties had been made on and as of the Closing.

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                           (b) All authorizations, approvals or permits, if any,
of any governmental authority or regulatory body of the United States or of any
state or of any securities exchange or trading market on which the Common Stock
is listed that are required in connection with the lawful issuance and sale of
Shares pursuant to this Agreement shall have been duly obtained and effective as
of the Closing and all filings with such authorities or regulatory bodies shall
have been made and accepted.

                           (c) The Purchaser shall have performed and complied
with all agreements, obligations and conditions contained in this Agreement that
are required to be performed or complied with by it on or before the Closing.

                           (d) The Purchaser shall have paid the purchase price
as set forth in Section 1 above.

                           (e) The Purchaser shall have executed and delivered
the Registration Rights Agreement.

                           (f) The Purchaser shall have executed and delivered
the License Agreements.

                           (g) The Purchaser shall have delivered the first
milestone payment of USD $5,000,000 pursuant to the License Agreement.

                           (h) All corporate and other proceedings in connection
with the transactions contemplated at the Closing and all documents incident
thereto shall be reasonably satisfactory in form and substance to Company's
counsel.

         SECTION 7. Survival of Representations and Warranties. The
representations and warranties provided for in this Agreement shall survive for
one year from the Closing Date, except for those representations and warranties
which address matters only as of a particular date, which shall remain true and
correct as of such particular date.

         SECTION 8. Miscellaneous.

                  8.01 Notices. All notices, requests and other communications
to any party hereunder shall be in writing (including telecopier or similar
writing) and shall be given to such party at its address or telecopier number as
set forth below, or such other address or telecopier number as such party may
hereinafter specify for the purpose of giving notice hereunder to the party
giving such notice. Each such notice, request or other communication shall be
effective: (i) if given by telecopier, when such telecopier is transmitted to
the telecopier number specified pursuant to this Section 8.01 and the
appropriate confirmation is received or; (ii) if given by mail, 72 hours after
such communication is deposited in the mails, certified mail, return receipt
requested, postage prepaid, addressed as aforesaid or; (iii) if given by any
other means, when delivered at the address as follows:

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         If to the Company, to:

                 ISTA Pharmaceuticals, Inc.

                 15279 Alton Parkway #100

                 Irvine, California  92618

                 Attention:  J.C. MacRae

                 Telecopier: (949) 789-7744

         With a copy to:

                 Wilson Sonsini Goodrich & Rosati

                 650 Page Mill Road

                 Palo Alto, CA 94304

                 Attention: Issac Vaughn

                 Telecopier:  (650) 493-6811

         If to Purchaser, to:

                  Otsuka Pharmaceutical Co., Ltd.

                  3-2-27, Otedori

                  Chuo-ku

                  Osaka, Japan

                  Attn:

                  Tel: (6) 6231-7067

                  Telecopier:

         With a copy to:

                  Heller, Ehrman, White & McAuliffe, LLP

                  701 Fifth Avenue, Suite 6100

                  Seattle, WA 98104

                  Attn:  Kevin F. Kelly

                  Fax:  206-447-0849

                  Tel:  206-447-0900

                  8.02 Amendments and Waivers.

                           (a) Any term of this Agreement may be amended and the
observance of any term of this Agreement may be waived (either generally or in a
particular instance and either retroactively or prospectively), only with the
written consent of the Company and the Purchaser. Any amendment or waiver
effected in accordance with this paragraph shall be binding upon each holder of
any securities purchased under this Agreement at the time outstanding (including
securities into which such securities are convertible), each future holder of
all such securities, and the Company.

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                           (b) No failure or delay by any party in exercising
any right, power or privilege hereunder shall operate as a waiver thereof nor
shall any single or partial exercise thereof preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. The
rights and remedies herein provided shall be cumulative and not exclusive of any
rights or remedies provided by law.

                  8.03 Successors and Assigns. The provisions of this Agreement
shall be binding upon and inure to the benefit of the parties hereto and their
respective successors and assigns; provided, however, that no party may assign,
delegate or otherwise transfer any of its rights or obligations under this
Agreement without the consent of the other party.

                  8.04 Governing Law. This Agreement and all matters arising
directly or indirectly herefrom shall be governed by, and construed in
accordance with, the laws of the State of California without regard to the
conflicts of laws principles thereof.

                  8.05 Consent to Jurisdiction. The parties hereto agree that
any suit, action or proceeding relating to or arising out of this Agreement or
the transactions contemplated hereby, shall be brought in the federal and state
courts located in Orange County, California, so long as one of such courts shall
have subject matter jurisdiction over such suit, action or proceeding, and that
any cause of action arising out of this Agreement directly or indirectly shall
be deemed to have arisen from a transaction of business in the State of
California, and each of the parties hereby irrevocably consents to the
jurisdiction of such courts (and of the appropriate appellate courts therefrom)
in any such suit, action or proceeding and irrevocably waives, to the fullest
extent permitted by law, any objection that it may now or hereafter have to the
laying of the venue of any such suit, action or proceeding in any such court or
that any such suit, action or proceeding which is brought in any such court has
been brought in an inconvenient forum. Process in any such suit, action or
proceeding may be served on any party anywhere in the world, whether within or
outside the jurisdiction of any such court. Without limiting the foregoing, each
party agrees that service of process on such party as provided in Section 8.01
shall be deemed effective service of process on such party.

                  8.06 WAIVER OF JURY TRIAL. THE COMPANY AND THE PURCHASER EACH
HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL
PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS
CONTEMPLATED HEREBY.

                  8.07 Counterparts; Facsimile Signatures. This Agreement may be
executed in counterparts, each of which shall be deemed an original agreement,
but all of which together shall constitute one and the same instrument.
Execution and delivery of this Agreement by facsimile transmission shall
constitute execution and delivery of this Agreement for all purposes, with the
same force and effect as execution and delivery of an original manually signed
copy hereof.

                  8.08 Entire Agreement. This Agreement, the Registration Rights
Agreement, and the License Agreements constitute the entire agreement and
understanding between the parties hereto and supersedes any and all prior
agreements and understandings, written or oral, relating to the subject matter
of this Agreement, the Registration Rights Agreement, and the License
Agreements.

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<PAGE>
                  8.09 Headings. The headings in this Agreement are included for
convenience of reference only and shall be ignored in the construction or
interpretation hereof.

                  8.10 Attorneys Fees. In the event any suit or action is
instituted to enforce any provision in this Agreement, the substantially
prevailing party in such dispute shall be entitled to recover from the losing
party all fees, costs and expenses of enforcing any right of such prevailing
party under or with respect to this Agreement, including without limitation,
such reasonable fees and expenses of attorneys and accountants, which shall
include, without limitation, all fees, costs and expenses of appeal.

                  8.11 Severability. Any provision of this Agreement that is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof but shall be interpreted as if it
were written so as to be enforceable to the maximum extent permitted by
applicable law, and any such prohibition or unenforceability in any jurisdiction
shall not invalidate or render unenforceable such provision in any other
jurisdiction. To the extent permitted by applicable law, the parties hereby
waive any provision of law which renders any provisions hereof prohibited or
unenforceable in any respect.

                                      -12-
<PAGE>
         IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their duly authorized representatives as of the day and year first
above written.

                                           ISTA PHARMACEUTICALS, INC.

                                           By:      /s/ J.C. MacRae
                                              ----------------------------------
                                              Name:   J.C. MacRae

                                              Title:  Executive Vice President,

                                              Chief Operating Offer and

                                              Chief Financial Officer

                                           OTSUKA PHARMACEUTICAL CO., LTD.

                                           By:      /s/ Ichiro Otsuka
                                              ----------------------------------
                                              Name:   Ichiro Otsuka

                                              Title:  Managing Director<PAGE>
                                                                   EXHIBIT 10.24

                          REGISTRATION RIGHTS AGREEMENT

         This Registration Rights Agreement (the "Agreement") is made as of
December 13, 2001, by and among ISTA Pharmaceuticals Inc. (the "Company"), a
Delaware corporation, with its principal place of business at 15279 Alton
Parkway #100, Irvine, California 92618, and Otsuka Pharmaceutical Co., a
corporation organized under the laws of Japan, with a principal place of
business at 2-9, Kanda Tsukasa-cho, Chiyoda-ku, Tokyo 101-8535, Japan (the
"Investor").

         WHEREAS, the Company proposes to issue and sell to the Investor an
aggregate of 845,665 shares (the "Shares") of the Company's Common Stock, par
value $.001 per share (the "Common Stock"), pursuant to a Securities Purchase
Agreement dated as of the date hereof among the Investor and the Company (the
"Purchase Agreement"); and

         WHEREAS, the obligations in the Purchase Agreement are conditioned upon
the execution and delivery of this Agreement; and

         WHEREAS, pursuant to the Purchase Agreement, the Company has agreed to
effect the registration of the Shares on the terms and conditions set forth
herein.

         NOW, THEREFORE, in consideration of the covenants and agreements set
forth herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto covenant and
agree as follows:

                                    ARTICLE I
                                   DEFINITIONS

         SECTION 1.1 DEFINITIONS. As used in this Agreement, the following terms
shall have the following respective meanings:

                  "AFFILIATE" of any Person as of any date means: (a) any other
Person controlled by, controlling or under "common control" as that term is
defined in the Securities Act with that Person as of such date (including
Persons under common investment management); (b) in the case of any trust that
is a stockholder of the Company, any beneficiary of that trust as of such date
who is entitled to the majority of the assets of that trust; and (c) in the case
of any custodial account that is a stockholder of the Company, any beneficiary
of that custodial account as of such date.

                  "CLOSING DATE" shall mean the closing date under the Purchase
Agreement.

                  "COMMISSION" shall mean the Securities and Exchange Commission
and any successor agency of the Federal government administering the Securities
Act and the Exchange Act.
<PAGE>
                  "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934,
as amended, and any similar or successor Federal statute, and the rules and
regulations of the Commission thereunder, all as the same shall be in effect
from time to time.

                  "PERSON" shall mean an individual, corporation, partnership,
limited liability company, joint venture, trust or unincorporated organization,
or a government or any agency or political subdivision thereof.

                  "REGISTER", "REGISTERED" and "REGISTRATION" shall refer to a
registration effected by preparing and filing a registration statement in
compliance with the Securities Act and applicable rules and regulations
thereunder, and the declaration or ordering of the effectiveness of such
registration statement, or, as the context may require, under the Exchange Act
or applicable state securities laws.

                  "REGISTRABLE SECURITIES" shall mean the Shares and any Common
Stock of the Company issued as (or issuable upon conversion of any warrant,
right or other security which is issued as) a dividend or other distribution
with respect to, or in exchange for or in replacement of, such above-described
securities. Notwithstanding the foregoing, the term Registrable Securities shall
not include (a) any such securities which have been registered under the
Securities Act pursuant to an effective registration statement filed thereunder
and disposed of in accordance with the registration statement covering them, (b)
any such securities which have been publicly sold pursuant to Rule 144 under the
Securities Act, or (c) any such securities held by and issuable to any holder if
all such securities held by such holder (and its Affiliates) may be sold under
Rule 144 under the Securities Act during any ninety (90) day period.

                  "REGISTRATION EXPENSES" shall mean all expenses incurred by
the Company in complying with Sections 2.1 and 2.2, including, without
limitation, all registration and filing fees, printing expenses, fees and
disbursements of counsel and independent public accountants for the Company,
fees and expenses (including counsel fees) incurred in connection with complying
with state securities or "blue sky" laws, transfer taxes, fees of transfer
agents and registrars, and, with respect to each registration effected or
proposed to be effected hereunder, up to $35,000 of fees and disbursements of a
single counsel selected by the Investor representing all sellers of Registrable
Securities, excluding any Selling Expenses.

                  "SECURITIES ACT" shall mean the Securities Act of 1933, as
amended, and any similar or successor Federal statute, and the rules and
regulations of the Commission thereunder, all as the same shall be in effect
from time to time.

                  "SELLING EXPENSES" shall mean all fees and disbursements of
counsel to the sellers of Registrable Securities in excess of $35,000 and
underwriting discounts and selling commissions applicable to the sale of
Registrable Securities.

                                       2
<PAGE>
                                   ARTICLE II

                               REGISTRATION RIGHTS

         SECTION 2.1 SHELF REGISTRATION RIGHTS.

                  (a) As soon as practicable, but in any event within 60 days of
the Closing Date, the Company shall prepare and file with the Commission a
registration statement (the "Shelf Registration Statement") on Form S-3 (or, if
Form S-3 is not then available to the Company, on such form of registration
statement as is then available to effect a registration for resale of the
Shares), covering the resale of the Shares. In addition, the Company shall as
soon as practicable, effect such registration and all such qualifications and
compliances as may be so required or requested and as would permit or facilitate
the sale and distribution of all or a portion of the Registrable Securities, but
in any event shall (i) file within 30 days of any request by the Commission
amendments or supplements to the Shelf Registration Statement or the prospectus
used in connection therewith and (ii) provide within 30 days any additional
information requested by the Commission. If the Company fails to file the Shelf
Registration Statement within sixty days or to file upon the request of the
Commission an amendment or supplement or provide information requested by the
Commission within 30 days, the Company will be required to pay liquidated
damages of $2,000 to the Investor for each day after such 60 or 30 day deadline.

                  (b) The Company shall be required to maintain the
effectiveness of the Shelf Registration Statement until the "Termination Date"
which will be the earliest of (i) the date on which all such Registrable
Securities have been sold thereunder, (ii) the later of the second anniversary
of the effective date of such registration statement or the date which the
Investor owns less than 10% of the outstanding Common Stock of the Company, or
(iii) such time as all of the Registrable Securities may be sold pursuant to
Rule 144(k).

                  (c) Notwithstanding the foregoing, the Company shall be
entitled to suspend effectiveness of the Shelf Registration Statement for up to
90 days if the Company shall furnish to the Investor a certificate signed by the
Chairman of the Company stating that in the good faith judgment of the Board of
Directors of the Company, it would be seriously detrimental to the Company and
its stockholders for such Shelf Registration Statement to continue to be
effective because (i) the Company is engaged in any activity or transaction or
preparations or negotiations for any activity or transaction ("Company
Activity") that the Company desires to keep confidential for business reasons,
and the Company determines in good faith that the public disclosure requirement
imposed on the Company pursuant to the Shelf Registration Statement would
require disclosure of the Company Activity; or (ii) the Company files a
Registration Statement (other than the Registration Statement on Form S-4 or
Form S-8, or any successor form) with the Commission for the purpose of
registering under the Securities Act any securities to be publicly offered and
sold by the Company.

                  (d) Notwithstanding Section 2.1(c) above, the Company may not
utilize the right to suspend the effectiveness of the Shelf Registration
Statement more than once in any twelve-month period, and the Investor shall be
reimbursed for all Registration Expenses incurred prior to the receipt of such
certificate.The two year period set forth in Section 2.1(b)(ii) above shall be
tolled during any period which use of the Shelf Registration Statement is
suspended.

                                       3
<PAGE>
         SECTION 2.2. REGISTRATION PROCEDURES. In connection with any
registration under Section 2.1, the Company shall:

                  (a) Prepare and file with the Commission a registration
statement with respect to such securities, including executing an undertaking to
file post-effective amendments and use its commercially reasonable efforts to
cause such registration statement to become effective;

                  (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 for
the period specified herein and comply with the provisions of the Securities Act
with respect to the disposition of all Registrable Securities covered by such
registration statement in accordance with the sellers' intended method of
disposition set forth in such registration statement for such period;

                  (c) Furnish to each seller of Registrable Securities, such
number of conformed copies of the registration statement and each such amendment
and supplement thereto (in each case including all exhibits and documents filed
therewith) and the prospectus included therein (including each preliminary and
summary prospectus) and any other prospectus filed under Rule 424 under the
Securities Act in conformity with the requirements of the Securities Act as such
persons reasonably may request in order to facilitate the public sale or other
disposition of the Registrable Securities covered by such registration
statement;

                  (d) Use its commercially reasonable efforts to register or
qualify the Registrable Securities covered by such registration statement under
the securities or "blue sky" laws of such jurisdictions as the sellers of
Registrable Securities reasonably shall request, provided, however, that the
Company shall not for any such purpose be required to qualify generally to
transact business as a foreign corporation in any jurisdiction where it is not
so qualified or to consent to general service of process or submit to taxation
in any such jurisdiction, unless the Company is already subject to service or
subject to taxation in such jurisdiction;

                  (e) Cause the Registrable Securities covered by such
registration statement to be listed on any securities exchange or quotation
system on which the equity securities of the Company are then listed;

                  (f) Immediately notify each seller of Registrable Securities
at any time when a prospectus relating thereto is required to be delivered under
the Securities Act, of the happening of any event of which the Company has
knowledge as a result of which the prospectus contained in such registration
statement, as then in effect, includes an untrue statement of a material fact or
omits to state a material fact required to be stated therein or necessary to
make the statements therein not misleading in light of the circumstances then
existing, and promptly prepare and furnish to such seller a reasonable number of
copies of a prospectus supplemented or amended so that, as thereafter delivered
to the purchasers of such Registrable 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 light of the circumstances then existing;

                                       4
<PAGE>
                   (g) Notify each seller of Registrable Securities covered by
such registration statement (i) when the prospectus or any prospectus supplement
or post-effective amendment has been filed, and, with respect to such
registration statement or any post-effective amendment, when the same has become
effective, (ii) of any request by the Commission for amendments or supplements
to such registration statement or to amend or to supplement such prospectus or
for additional information, (iii) of the issuance by the Commission of any stop
order suspending the effectiveness of such registration statement or the
initiation of any proceeding for that purpose and (iv) of the suspension of the
qualification of such securities for offering or sale in any jurisdiction, or of
the institution of any proceeding for any of such purposes;

                  (h) In the event of any underwritten public offering, enter
into and perform its obligations under an underwriting agreement, in usual and
customary form, with the managing underwriter(s) of such offering, including
providing such underwriter(s) an opinion from counsel to the Company and a
letter from the independent certified public accountants of the Company. Each
seller of Registrable Securities participating in such underwriting shall also
enter into and perform its obligations under such an agreement;

                  (i) Use its commercially reasonable efforts to take all other
steps necessary to effect the registration of such Registrable Securities
contemplated hereby.

         SECTION 2.3 EXPENSES. The Company will pay all Registration Expenses in
connection with each registration statement under Section 2.1. All Selling
Expenses in connection with each registration statement under Section 2.1 shall
be borne by the participating sellers in proportion to the number of shares
registered by each, or by such participating sellers other than the Company as
they may agree.

         SECTION 2.4 RULE 144 REPORTING. With a view to making available to the
holders of Registrable Securities the benefits of Rule 144 promulgated under the
Securities Act ("Rule 144") and any other rule or regulation of the Commission
that may at any time permit the holders to sell the Registrable Securities to
the public without registration or pursuant to the Resale Registration
Statement, the Company covenants and agrees to: (i) make and keep public
information available, as those terms are understood and defined in Rule 144,
until the Termination Date; (ii) file with the Commission in a timely manner all
reports and other documents required of the Company under the Securities Act and
Exchange Act; and (iii) furnish to the holders of Registrable Securities upon
request (A) a written statement by the Company that it has complied with the
reporting requirements of the Securities Act and the Exchange Act and (B) a copy
of the most recent annual or quarterly report of the Company.

         SECTION 2.5 INDEMNIFICATION.

                  (a) The Company will indemnify each holder of Registrable
Securities, each of its officers, directors and partners, legal counsel, and
accountants and each Affiliate of such holder, with respect to which
registration, qualification, or compliance has been effected pursuant to this
Agreement, and each underwriter, if any, and each Affiliate of any such
underwriter, against all expenses, claims, losses, damages, and liabilities (or
actions, proceedings, or settlements in respect thereof) arising out of or based
on any untrue statement (or alleged untrue statement) of a material fact
contained in any prospectus, offering circular, or other document (including any
related registration statement, notification, or the like) incident to any such
registration,

                                       5
<PAGE>
qualification, or compliance, or based on 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, or any violation by the Company of the
Securities Act or any rule or regulation thereunder applicable to the Company
and relating to action or inaction required of the Company in connection with
any such registration, qualification, or compliance, and will reimburse each
such holder, each of its officers, directors, partners, legal counsel, and
accountants and each Affiliate of such holder, each such underwriter, and each
Affiliate of any such underwriter, for any reasonable legal and any other
expenses reasonably incurreded in connection with investigating and defending or
settling any such claim, loss, damage, liability, or action, provided that the
Company will not be liable in any such case to the extent that any such claim,
loss, damage, liability, or expense arises out of or is based on any untrue
statement or omission based upon written information furnished to the Company by
such holder or underwriter and stated to be specifically for use therein. It is
agreed that the indemnity agreement contained in this Section 2.5(a) shall not
apply to amounts paid in settlement of any such loss, claim, damage, liability,
or action if such settlement is effected without the consent of the Company
(which consent has not been unreasonably withheld).

                  (b) Each holder will, if Registrable Securities held by such
holder are included in the securities as to which such registration,
qualification, or compliance is being effected, indemnify the Company, each of
its directors, officers, partners, legal counsel, and accountants and each
underwriter, if any, of the Company's securities covered by such a registration
statement, each Affiliate of the Company or such underwriter, each other such
holder, and each of their officers, directors, and partners, and each Affiliate
of such holder, against all claims, losses, damages and liabilities (or actions
in respect thereof) arising out of or based on any untrue statement (or alleged
untrue statement) of a material fact contained in any such registration
statement, prospectus, offering circular, or other document, 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 will reimburse
the Company and such holders, directors, officers, partners, legal counsel, and
accountants, persons, underwriters, or Affiliate of such holder for any
reasonable legal or any other expenses reasonably incurred in connection with
investigating or defending any such claim, loss, damage, liability, or action,
in each case to the extent, but only to the extent, that such untrue statement
(or alleged untrue statement) or omission (or alleged omission) is made in such
registration statement, prospectus, offering circular, or other document in
reliance upon and in conformity with written information furnished to the
Company by such holder and stated to be specifically for use therein provided,
however, that the obligations of such holder hereunder shall not apply to
amounts paid in settlement of any such claims, losses, damages, or liabilities
(or actions in respect thereof if such settlement is effected without the
consent of such holder (which consent shall not be unreasonably withheld).

                  (c) Each party entitled to indemnification under this Section
2.5 (the "Indemnified Party") shall give notice to the party required to provide
indemnification (the "Indemnifying Party") promptly after such Indemnified Party
has actual knowledge of any claim as to which indemnity may be sought, and shall
permit the Indemnifying Party to assume the defense of such claim or any
litigation resulting therefrom, provided that counsel for the Indemnifying
Party, who shall conduct the defense of such claim or any litigation resulting
therefrom, shall be approved by the Indemnified Party (whose approval shall not
unreasonably be withheld), and the

                                       6
<PAGE>
Indemnified Party may participate in such defense at such party's expense, and
provided further that the failure of any Indemnified Party to give notice as
provided herein shall not relieve the Indemnifying Party of its obligations
under this Agreement, to the extent such failure is not prejudicial. No
Indemnifying Party, in the defense of any such claim or litigation, shall,
except with the consent of each Indemnified Party, consent to entry of any
judgment or enter into any settlement that 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. Each
Indemnified Party shall furnish such information regarding itself or the claim
in question as an Indemnifying Party may reasonably request in writing and as
shall be reasonably required in connection with defense of such claim and
litigation resulting therefrom.

                  (d) If the indemnification provided for in this Section 2.5 is
held by a court of competent jurisdiction to be unavailable to an Indemnified
Party with respect to any loss, liability, claim, damage, or expense referred to
therein, then the Indemnifying Party, in lieu of indemnifying such Indemnified
Party hereunder, shall contribute to the amount paid or payable by such
Indemnified Party as a result of such loss, liability, claim, damage, or expense
in such proportion as is appropriate to reflect the relative fault of the
Indemnifying Party on the one hand and of the Indemnified Party on the other in
connection with the statements or omissions that resulted in such loss,
liability, claim, damage, or expense as well as any other relevant equitable
considerations. The relative fault of the Indemnifying Party and of the
Indemnified Party shall be determined by reference to, among other things,
whether the untrue or alleged untrue statement of a material fact or the
omission to state a material fact relates to information supplied by the
Indemnifying Party or by the Indemnified Party and the parties' relative intent,
knowledge, access to information, and opportunity to correct or prevent such
statement or omission.

                  (e) Notwithstanding the foregoing, to the extent that the
provisions on indemnification and contribution contained in the underwriting
agreement entered into in connection with an underwritten public offering are in
conflict with the foregoing provisions, the provisions in the underwriting
agreement shall control.

                                   ARTICLE III
                                  MISCELLANEOUS

         SECTION 3.1 NOTICES. All notices, requests and other communications to
any party hereunder shall be given as provided in the Purchase Agreement.

         SECTION 3.2 ENTIRE AGREEMENT. This Agreement, the Purchase Agreement,
and the other documents delivered pursuant hereto and thereto constitutes the
entire agreement and understanding between the parties hereto and supersedes any
and all prior agreements and understandings, written or oral, relating to the
subject matter hereof

         SECTION 3.3 MODIFICATIONS AND AMENDMENTS. This Agreement may not be
amended or modified, and no provision hereof may be waived, without the written
consent of the Company and holders of at least a majority of the Registrable
Securities.

                                       7
<PAGE>
         SECTION 3.4 GOVERNING LAW. This Agreement and the rights and
obligations of the parties hereunder shall be construed in accordance with and
governed by the law of the State of California without giving effect to the
conflict of law principles thereof.

         SECTION 3.5 JURISDICTION AND SERVICE OF PROCESS. The parties hereto
agree that any suit, action or proceeding relating to or arising out of this
Agreement or the transactions contemplated hereby, shall be brought in the
federal and state courts located in Orange County, California, so long as one of
such courts shall have subject matter jurisdiction over such suit, action or
proceeding, and that any cause of action arising out of this Agreement directly
or indirectly shall be deemed to have arisen from a transaction of business in
the State of California, and each of the parties hereby irrevocably consents to
the jurisdiction of such courts (and of the appropriate appellate courts
therefrom) in any such suit, action or proceeding and irrevocably waives, to the
fullest extent permitted by law, any objection that it may now or hereafter have
to the laying of the venue of any such suit, action or proceeding in any such
court or that any such suit, action or proceeding which is brought in any such
court has been brought in an inconvenient forum. Process in any such suit,
action or proceeding may be served on any party anywhere in the world, whether
within or outside the jurisdiction of any such court. Without limiting the
foregoing, each party agrees that service of process on such party as provided
in Section 3.1 shall be deemed effective service of process on such party.

         SECTION 3.6 SEVERABILITY. Any provision of this Agreement that is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof but shall be interpreted as if it
were written so as to be enforceable to the maximum extent permitted by
applicable law, and any such prohibition or unenforceability in any jurisdiction
shall not invalidate or render unenforceable such provision in any other
jurisdiction. To the extent permitted by applicable law, the parties hereby
waive any provision of law which renders any provisions hereof prohibited or
unenforceable in any respect.

         SECTION 3.7 HEADINGS AND CAPTIONS. The headings and captions of the
various subdivisions of this Agreement are for convenience of reference only and
shall in no way modify or affect the meaning or construction of any of the terms
or provisions hereof.

         SECTION 3.8 COUNTERPARTS; FACSIMILE. This Agreement may be executed in
counterparts, each of which shall be deemed an original agreement, but all of
which together shall constitute one and the same instrument. Execution and
delivery of this Agreement by facsimile transmission shall constitute execution
and delivery of this Agreement for all purposes, with the same force and effect
as execution and delivery of an original manually signed copy hereof.

         SECTION 3.9 NO JURY TRIAL. THE COMPANY AND THE HOLDERS OF THE
REGISTRABLE SECURITIES EACH HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL
BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR
THE TRANSACTIONS CONTEMPLATED HEREBY.

                                       8
<PAGE>
         SECTION 3.10 SUCCESSORS AND ASSIGNS. The rights to cause the Company to
register Registrable Securities hereunder may be assigned by a holder of
Registrable Securities to a transferee or assignee of Registrible Securities;
provided, however that the transferor shall furnish to the Company written
notice of such transfer. The provisions hereof shall inure to the benefit of,
and be binding upon, the successors, assigns, heirs, executors, and
administrators of the parties hereto and shall inure to the benefit of and be
enforceable by each person who shall be a holder of Registrable Securities from
time to time.

         SECTION 3.11 ATTORNEYS FEES. In the event any suit or action is
instituted to enforce any provision in this Agreement, the substantially
prevailing party in such dispute shall be entitled to recover from the losing
party all fees, costs and expenses of enforcing any right of such prevailing
party under or with respect to this Agreement, including without limitation,
such reasonable fees and expenses of attorneys and accountants, which shall
include, without limitation, all fees, costs and expenses of appeal.

                                     * * *

                                       9
<PAGE>
         IN WITNESS WHEREOF, the parties hereto have executed this Agreement or
caused this Agreement to be executed by their duly authorized representatives,
as of the date first written above. ISTA PHARMACEUTICALS INC.

                                   By:          /s/ J.C. MacRae
                                            ------------------------------------
                                            Name:    J.C. MacRae
                                            Title:   Executive Vice President,
                                                     Chief Operating Offer and
                                                     Chief Financial Officer

                                   OTSUKA PHARMACEUTICAL CO., LTD.

                                   By:          /s/ Ichiro Otsuka
                                            ------------------------------------
                                            Name:    Ichiro Otsuka
                                            Title:   Managing Director

                                       10

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