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Exhibit 4.2



        1.    Purpose. Titan Pharmaceuticals, Inc., a Delaware corporation ("Titan"), desires to attract and retain the best available talent and to encourage the highest level of performance. The Titan Pharmaceuticals, Inc. 2002 Stock Option Plan (the "Plan") is intended to contribute significantly to the attainment of these objectives by affording eligible employees and independent contractors of Titan and its Affiliates (as defined in Section 23) (collectively, with Titan, the "Company") the opportunity to acquire a proprietary interest in Titan through the grant of stock options ("Options") to purchase shares of common stock, $.001 par value per share, of Titan (the "Common Stock").

        2.    Administration.

        3.    Type of Options. Options granted under the Plan may be either incentive stock options ("ISOs") intended to meet the requirements of Code Section 422 or nonqualified stock options ("NSOs") which are not intended to meet such Code requirements.

        4.    Eligible Persons. Subject in the case of ISOs to Section 16(a), Options may be granted to employees, officers and directors of, and consultants and advisors to, the Company. In determining the persons to whom awards shall be made and the number of shares to be covered by each Option, the Committee shall take into account the duties of the respective persons, their present and potential contributions to the success of the Company and other factors deemed relevant by the Committee in connection with accomplishing the purposes of the Plan.

        5.    Share Limitations under the Plan.

        6.    Term of Options. The term of each Option shall be fixed by the Committee and specified in the applicable Option Agreement, but in no event shall it be more than ten years from the date of grant, subject to earlier termination as provided in Section 8. Subject in the case of ISOs to Section 16, the term of an Option may be extended from time to time by the Committee, provided that no extension shall extend the term beyond ten years from the date of grant.

        7.    Vesting. The Committee shall determine the vesting schedule applicable to a particular Option grant and specify the vesting schedule in the applicable Option Agreement. Notwithstanding the foregoing the Committee may accelerate the vesting of an Option at any time.

        8.    Termination of Relationship to the Company.

        9.    Option Price. Subject in the case of ISOs to Section 16, the exercise price per share of Common Stock covered by an Option shall be established by the Committee; provided, however, that (a) the exercise price per share for any Option shall not be less than one-hundred-percent (100%) of the Fair Market Value of a share of Common Stock on the date the Option is granted and (b) no ISO granted to a 10% Shareholder (as defined in Section 16) shall have a exercise price per share less than one hundred ten percent (110%) of the Fair Market Value of a share of Common Stock on the date the Option is granted. Notwithstanding the foregoing, an Option (whether an ISO or NSO) may be granted with an exercise price lower than the minimum exercise price set forth above if such Option is granted pursuant to an assumption or substitution for another option in a manner qualifying under the provision of Section 424(a) of the Code.

        10.  Exercise of Options.

        11.  Option Agreement. The terms and conditions of each Option shall be set forth in an Option Agreement in the form approved by the Committee. Each Option Agreement shall, at a minimum, specify (i) the number of shares of Common Stock subject to the Option, (ii) whether the Option is intended to be an ISO or NSO, (iii) the provisions related to vesting and exercisability of the Option, including the Option exercise price, and (iv) that the Option is subject to the terms and provisions of the Plan. Option Agreements may differ from one another.

        12.  No Stockholder Rights. No Optionee shall have the rights of a stockholder with respect to shares covered by an Option until such person becomes the holder of record of such shares.

        13.  Nontransferability.

        14.  Compliance with Law; Registration of Shares.

        15.  Adjustments upon Changes in Capitalization.

        16.  ISO Provisions.

        17.  No Right to Continued Employment. Neither the Plan nor any action taken hereunder shall be construed as giving any employee or any independent contractor any right to continue in the employ of or to be engaged as an independent contractor by the Company or affect the right of the Company to terminate such person's employment or other relationship with the Company at any time.

        18.  Amendment; Early Termination. Subject to Section 22, the Board may at any time and from time to time alter, amend, suspend or terminate the Plan in whole or in part; provided, however, that no amendment requiring stockholder approval by law or by the rules of any stock exchange, inter-dealer quotation system, or other market in which shares of Common Stock are traded, shall be effective unless and until such stockholder approval has been obtained in compliance with such rule or law; and provided, further, that no such amendment shall materially adversely affect the rights of an Optionee in any Option previously granted under the Plan without the Optionee's written consent.

        19.  Effective Date. The Plan shall be effective as of the date of its adoption by the Board (the "Effective Date"), subject to the approval thereof by the stockholders of Titan entitled to vote thereon within 12 months of such date. In the event that such stockholder approval is not obtained within such time period, the Plan and any Options granted under the Plan on or prior to the expiration of such 12 month period shall be void and of no further force and effect.

        20.  Termination of Plan. Unless terminated earlier by the Board in accordance with Section 18 above, the Plan shall terminate on, and no further Options may be granted after, the tenth anniversary of the Effective Date.

        21.  Severability. In the event that any one or more provisions of the Plan or an Option Agreement, or any action taken pursuant to the Plan or an Option Agreement, should, for any reason, be unenforceable or invalid in any respect under the laws of the United States, any state of the United States or any other jurisdiction, such unenforceability or invalidity shall not affect any other provision of the Plan or Option Agreement, but in such particular jurisdiction and instance the Plan and/or Option Agreement, as applicable, shall be construed as if such unenforceable or invalid provision had not been contained therein or if the action in question had not been taken thereunder.

        22.  Cancellation and New Grant of Options, Etc. The Committee shall have the authority to effect, at any time and from time to time, with the consent of the affected Optionees, (i) the cancellation of any or all outstanding options under the Plan and the grant in substitution therefor of new options

under the Plan covering the same or different numbers of shares of Common Stock and having an option exercise price per share which may be lower or higher than the exercise price per share of the cancelled options or (ii) the amendment of the terms of any and all outstanding options under the Plan to provide an option exercise price per share which is higher or lower than the then-current exercise price per share of such outstanding options; provided, however, that the Committee shall not take any of the actions described in (i) or (ii) hereof without receiving the approval of Titan's stockholders. The provisions of this Section 22 may not be altered or amended without stockholder approval.

        23.  Definitions.