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                                                                    EXHIBIT 10.4

                          SIGNAL PHARMACEUTICALS, INC.

                            STOCK OPTION GRANT NOTICE
                          (2000 EQUITY INCENTIVE PLAN)


SIGNAL PHARMACEUTICALS, INC. (the "Company"), pursuant to its 2000 Equity
Incentive Plan (the "Plan"), hereby grants to Optionee an option to purchase the
number of shares of the Company's common stock set forth below. This option is
subject to all of the terms and conditions as set forth herein and in
Attachments I, II and III, which are incorporated herein in their entirety.

Optionee:                       _________________________________
Date of Grant:                  _________________________________
Vesting Commencement Date:      _________________________________
Shares Subject to Option:       _________________________________
Exercise Price Per Share:       _________________________________
Expiration Date:                _________________________________

                  ____ Incentive Stock Option ____ Nonstatutory Stock Option

        EXERCISE SCHEDULE:   Exercisable as vested.

        VESTING SCHEDULE:    One fourth (1/4th) of the shares subject to this
                             option shall vest on the first anniversary of the
                             date of grant of this option and the balance of
                             the shares shall vest in equal successive monthly
                             installments over each of the next thirty-six (36)
                             months until this option is fully vested or vesting
                             terminates as provided in the Plan or the Stock
                             Option Agreement.

PAYMENT: Any one or a combination of the following: (i) by cash or check, (ii)
pursuant to a Regulation T program, as set forth in the Stock Option Agreement
or (iii) by delivering shares of previously-owned common stock of the Company,
as set forth in the Stock Option Agreement.

ADDITIONAL TERMS/ACKNOWLEDGEMENTS: The undersigned Optionee acknowledges receipt
of, and understands and agrees to, this Grant Notice, the Stock Option Agreement
and the Plan. Optionee further acknowledges that as of the Date of Grant, this
Grant Notice, the Stock Option Agreement and the Plan set forth the entire
understanding between Optionee and the Company regarding the acquisition of
stock in the Company and supersedes all prior oral and written agreements on
that subject with the exception of (i) options previously granted and delivered
to Optionee under the Plan, and (ii) the following agreements only:

        OTHER AGREEMENTS:
                         -----------------------------------------

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

SIGNAL PHARMACEUTICALS, INC.                OPTIONEE:

By:
   --------------------------------         Signature
Title:                                      ------------------------------------
      -----------------------------
Date:
     ------------------------------


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Attachment I:      Stock Option Agreement
Attachment II:     2000 Equity Incentive Plan
Attachment III:    Notice of Exercise


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                          SIGNAL PHARMACEUTICALS, INC.
                           2000 EQUITY INCENTIVE PLAN

                             STOCK OPTION AGREEMENT
                   (INCENTIVE AND NONSTATUTORY STOCK OPTIONS)


        Pursuant to your Stock Option Grant Notice ("Grant Notice") and this
Stock Option Agreement, Signal Pharmaceuticals, Inc. (the "Company") has granted
you an option under its 2000 Equity Incentive Plan (the "Plan") to purchase the
number of shares of the Company's Common Stock indicated in your Grant Notice at
the exercise price indicated in your Grant Notice. Defined terms not explicitly
defined in this Stock Option Agreement but defined in the Plan shall have the
same definitions as in the Plan.

        The details of your option are as follows:

        1.      VESTING. Subject to the limitations contained herein, your
option will vest as provided in your Grant Notice, provided that vesting will
cease upon the termination of your Continuous Service.

        2.      NUMBER OF SHARES AND EXERCISE PRICE. The number of shares of
Common Stock subject to your option and your exercise price per share referenced
in your Grant Notice may be adjusted from time to time for Capitalization
Adjustments, as provided in the Plan.

        3.      EXERCISE PRIOR TO VESTING ("EARLY EXERCISE"). If permitted in
your Grant Notice (i.e., the "Exercise Schedule" indicates that "Early Exercise"
of your option is permitted) and subject to the provisions of your option, you
may elect at any time that is both (i) during the period of your Continuous
Service and (ii) during the term of your option, to exercise all or part of your
option, including the nonvested portion of your option; provided, however, that:

               (a) a partial exercise of your option shall be deemed to cover
first vested shares of Common Stock and then the earliest vesting installment of
unvested shares of Common Stock;

               (b) any shares of Common Stock so purchased from installments
that have not vested as of the date of exercise shall be subject to the purchase
option in favor of the Company as described in the Company's form of Early
Exercise Stock Purchase Agreement;

               (c) you shall enter into the Company's form of Early Exercise
Stock Purchase Agreement with a vesting schedule that will result in the same
vesting as if no early exercise had occurred; and

               (d) if your option is an incentive stock option, then, as
provided in the Plan, to the extent that the aggregate Fair Market Value
(determined at the time of grant) of the shares of Common Stock with respect to
which your option plus all other incentive stock options you hold are
exercisable for the first time by you during any calendar year (under all plans
of the Company and its Affiliates) exceeds one hundred thousand dollars
($100,000), your option(s) or portions thereof that exceed such limit (according
to the order in which they were granted) shall be treated as nonstatutory stock
options.


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        4.      METHOD OF PAYMENT. Payment of the exercise price is due in full
upon exercise of all or any part of your option. You may elect to make payment
of the exercise price in cash or by check or in any other manner PERMITTED BY
YOUR GRANT NOTICE, which may include one or more of the following:

               (a) In the Company's sole discretion at the time your option is
exercised and provided that at the time of exercise the Common Stock is publicly
traded and quoted regularly in The Wall Street Journal, pursuant to a program
developed under Regulation T as promulgated by the Federal Reserve Board that,
prior to the issuance of Common Stock, results in either the receipt of cash (or
check) by the Company or the receipt of irrevocable instructions to pay the
aggregate exercise price to the Company from the sales proceeds.

               (b) Provided that at the time of exercise the Common Stock is
publicly traded and quoted regularly in The Wall Street Journal, by delivery of
already-owned shares of Common Stock either that you have held for the period
required to avoid a charge to the Company's reported earnings (generally six
months) or that you did not acquire, directly or indirectly from the Company,
that are owned free and clear of any liens, claims, encumbrances or security
interests, and that are valued at Fair Market Value on the date of exercise.
"Delivery" for these purposes, in the sole discretion of the Company at the time
you exercise your option, shall include delivery to the Company of your
attestation of ownership of such shares of Common Stock in a form approved by
the Company. Notwithstanding the foregoing, you may not exercise your option by
tender to the Company of Common Stock to the extent such tender would violate
the provisions of any law, regulation or agreement restricting the redemption of
the Company's stock.

        5.      WHOLE SHARES. You may exercise your option only for whole shares
of Common Stock.

        6.      SECURITIES LAW COMPLIANCE. Notwithstanding anything to the
contrary contained herein, you may not exercise your option unless the shares of
Common Stock issuable upon such exercise are then registered under the
Securities Act or, if such shares of Common Stock are not then so registered,
the Company has determined that such exercise and issuance would be exempt from
the registration requirements of the Securities Act. The exercise of your option
must also comply with other applicable laws and regulations governing your
option, and you may not exercise your option if the Company determines that such
exercise would not be in material compliance with such laws and regulations.

        7.      TERM. You may not exercise your option before the commencement
of its term or after its term expires. The term of your option commences on the
Date of Grant and expires upon the EARLIEST of the following:

               (a) three (3) months after the termination of your Continuous
Service for any reason other than your Disability or death, provided that if
during any part of such three- (3-) month period your option is not exercisable
solely because of the condition set forth in the preceding paragraph relating to
"Securities Law Compliance," your option shall not expire until the earlier of
the Expiration Date or until it shall have been exercisable for an aggregate
period of three (3) months after the termination of your Continuous Service;

               (b) twelve (12) months after the termination of your Continuous
Service due to your Disability;


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               (c) twelve (12) months after your death if you die either during
your Continuous Service or within three (3) months after your Continuous Service
terminates;

               (d) the Expiration Date indicated in your Grant Notice; or

               (e) the day before the tenth (10th) anniversary of the Date of
Grant.

        If your option is an incentive stock option, note that, to obtain the
federal income tax advantages associated with an "incentive stock option," the
Code requires that at all times beginning on the date of grant of your option
and ending on the day three (3) months before the date of your option's
exercise, you must be an employee of the Company or an Affiliate, except in the
event of your death or Disability. The Company has provided for extended
exercisability of your option under certain circumstances for your benefit but
cannot guarantee that your option will necessarily be treated as an "incentive
stock option" if you continue to provide services to the Company or an Affiliate
as a Consultant or Director after your employment terminates or if you otherwise
exercise your option more than three (3) months after the date your employment
terminates.

        8.      EXERCISE.

               (a) You may exercise the vested portion of your option (and the
unvested portion of your option if your Grant Notice so permits) during its term
by delivering a Notice of Exercise (in a form designated by the Company)
together with the exercise price to the Secretary of the Company, or to such
other person as the Company may designate, during regular business hours,
together with such additional documents as the Company may then require.

               (b) By exercising your option you agree that, as a condition to
any exercise of your option, the Company may require you to enter into an
arrangement providing for the payment by you to the Company of any tax
withholding obligation of the Company arising by reason of (1) the exercise of
your option, (2) the lapse of any substantial risk of forfeiture to which the
shares of Common Stock are subject at the time of exercise, or (3) the
disposition of shares of Common Stock acquired upon such exercise.

               (c) If your option is an incentive stock option, by exercising
your option you agree that you will notify the Company in writing within fifteen
(15) days after the date of any disposition of any of the shares of the Common
Stock issued upon exercise of your option that occurs within two (2) years after
the date of your option grant or within one (1) year after such shares of Common
Stock are transferred upon exercise of your option.

        9.      TRANSFERABILITY. Your option is not transferable, except by will
or by the laws of descent and distribution, and is exercisable during your life
only by you. Notwithstanding the foregoing, by delivering written notice to the
Company, in a form satisfactory to the Company, you may designate a third party
who, in the event of your death, shall thereafter be entitled to exercise your
option.

        10.     RIGHT OF FIRST REFUSAL. Shares of Common Stock that you acquire
upon exercise of your option are subject to any right of first refusal that may
be described in the Company's bylaws in effect at such time the Company elects
to exercise its right. The Company's right of first refusal shall expire on the
Listing Date.


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        11.     RIGHT OF REPURCHASE. To the extent provided in the Company's
bylaws as amended from time to time, the Company shall have the right to
repurchase all or any part of the shares of Common Stock you acquire pursuant to
the exercise of your option.

        12.     OPTION NOT A SERVICE CONTRACT. Your option is not an employment
or service contract, and nothing in your option shall be deemed to create in any
way whatsoever any obligation on your part to continue in the employ of the
Company or an Affiliate, or of the Company or an Affiliate to continue your
employment. In addition, nothing in your option shall obligate the Company or an
Affiliate, their respective shareholders, Boards of Directors, Officers or
Employees to continue any relationship that you might have as a Director or
Consultant for the Company or an Affiliate.

        13.     WITHHOLDING OBLIGATIONS.

               (a) At the time you exercise your option, in whole or in part, or
at any time thereafter as requested by the Company, you hereby authorize
withholding from payroll and any other amounts payable to you, and otherwise
agree to make adequate provision for (including by means of a "cashless
exercise" pursuant to a program developed under Regulation T as promulgated by
the Federal Reserve Board to the extent permitted by the Company), any sums
required to satisfy the federal, state, local and foreign tax withholding
obligations of the Company or an Affiliate, if any, which arise in connection
with your option.

               (b) Upon your request and subject to approval by the Company, in
its sole discretion, and compliance with any applicable conditions or
restrictions of law, the Company may withhold from fully vested shares of Common
Stock otherwise issuable to you upon the exercise of your option a number of
whole shares of Common Stock having a Fair Market Value, determined by the
Company as of the date of exercise, not in excess of the minimum amount of tax
required to be withheld by law. If the date of determination of any tax
withholding obligation is deferred to a date later than the date of exercise of
your option, share withholding pursuant to the preceding sentence shall not be
permitted unless you make a proper and timely election under Section 83(b) of
the Code, covering the aggregate number of shares of Common Stock acquired upon
such exercise with respect to which such determination is otherwise deferred, to
accelerate the determination of such tax withholding obligation to the date of
exercise of your option. Notwithstanding the filing of such election, shares of
Common Stock shall be withheld solely from fully vested shares of Common Stock
determined as of the date of exercise of your option that are otherwise issuable
to you upon such exercise. Any adverse consequences to you arising in connection
with such share withholding procedure shall be your sole responsibility.

               (c) You may not exercise your option unless the tax withholding
obligations of the Company and/or any Affiliate are satisfied. Accordingly, you
may not be able to exercise your option when desired even though your option is
vested, and the Company shall have no obligation to issue a certificate for such
shares of Common Stock or release such shares of Common Stock from any escrow
provided for herein.

        14.     NOTICES. Any notices provided for in your option or the Plan
shall be given in writing and shall be deemed effectively given upon receipt or,
in the case of notices delivered by mail by the Company to you, five (5) days
after deposit in the United States mail, postage prepaid, addressed to you at
the last address you provided to the Company.


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        15.     GOVERNING PLAN DOCUMENT. Your option is subject to all the
provisions of the Plan, the provisions of which are hereby made a part of your
option, and is further subject to all interpretations, amendments, rules and
regulations which may from time to time be promulgated and adopted pursuant to
the Plan. In the event of any conflict between the provisions of your option and
those of the Plan, the provisions of the Plan shall control.


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                               NOTICE OF EXERCISE


Signal Pharmaceuticals, Inc.
5555 Oberlin Drive
San Diego, CA  92121

                                                      Date of Exercise:_________

Ladies and Gentlemen:

        This constitutes notice under my stock option that I elect to purchase
the number of shares for the price set forth below.

        Type of option:                      ___ Incentive     ___ Nonstatutory

        Stock option dated:                  __________________

        Number of shares as
        to which option is
        exercised:                           __________________

        Certificates to be
        issued in name of:                   __________________

        Total exercise price:                $_________________

        Cash payment delivered
        herewith:                            $_________________

        Value of ______ shares of
        Signal Pharmaceuticals, Inc.
        common stock delivered herewith(1):  $_________________

        By this exercise, I agree (i) to provide such additional documents as
you may require pursuant to the terms of the Signal Pharmaceuticals, Inc. 2000
Equity Incentive Plan, (ii) to provide for the payment by me to you (in the
manner designated by you) of your withholding obligation, if any, relating to
the exercise of the Option, and (iii) to the extent the Option is an incentive
stock option, to notify you in writing within fifteen (15) days after the date
of any disposition of any of the shares of Common Stock issued upon exercise of
this Option that occurs within two (2) years after the date of grant of the
Option or within one (1) year after such shares of Common Stock are issued upon
exercise of the Option.

--------
(1) Shares must meet the public trading requirements set forth in the option.
Shares must be valued in accordance with the terms of the option being
exercised, must have been owned for the minimum period required in the option,
and must be owned free and clear of any liens, claims, encumbrances or security
interests. Certificates must be endorsed or accompanied by an executed
assignment separate from certificate.


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        I hereby make the following certification and representation with
respect to the number of shares of Common Stock (the "Shares"), which are being
acquired by me for my own account upon exercise of the Option as set forth
above:

        I acknowledge that all certificates representing any of the Shares
subject to the provisions of the Option shall have endorsed thereon appropriate
legends reflecting any restrictions imposed pursuant to the Company's Articles
of Incorporation, Bylaws and/or applicable securities laws.

                                          Very truly yours,


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


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