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                                                                   EXHIBIT 10.11

                                 SANTARUS, INC.
                             1998 STOCK OPTION PLAN

                      (as amended through December 3, 2003)

1.       ESTABLISHMENT, PURPOSE AND TERM OF PLAN.

         1.1      ESTABLISHMENT. The Santarus, Inc. 1998 Stock Option Plan (the
"PLAN") is hereby established effective as of October 30, 1998 (the "EFFECTIVE
DATE").

         1.2      PURPOSE. The purpose of the Plan is to advance the interests
of the Participating Company Group and its shareholders by providing an
incentive to attract, retain and reward persons performing services for the
Participating Company Group and by motivating such persons to contribute to the
growth and profitability of the Participating Company Group.

         1.3      TERM OF PLAN. The Plan shall continue in effect until the
earlier of its termination by the Board or the date on which all of the shares
of Stock available for issuance under the Plan have been issued and all
restrictions on such shares under the terms of the Plan and the agreements
evidencing Options granted under the Plan, if any, have lapsed. However, all
Options shall be granted, if at all, within ten (10) years from the earlier of
the date the Plan is adopted by the Board or the date the Plan is duly approved
by the shareholders of the Company.

2.       DEFINITIONS AND CONSTRUCTION.

         2.1      DEFINITIONS. Whenever used herein, the following terms shall
have the meanings set forth below:

                  (a)      "BOARD" means the Board of Directors of the Company.
If one or more Committees have been appointed by the Board to administer the
Plan, "BOARD" also means such Committee(s).

                  (b)      "CODE" means the Internal Revenue Code of 1986, as
amended, and any applicable regulations promulgated thereunder.

                  (c)      "COMMITTEE" means the Compensation Committee or other
committee of the Board duly appointed to administer the Plan and having such
powers as shall be specified by the Board. Unless the powers of the Committee
have been specifically limited, the Committee shall have all of the powers of
the Board granted herein, including, without limitation, the power to amend or
terminate the Plan at any time, subject to the terms of the Plan and any
applicable limitations imposed by law.

                  (d)      "COMPANY" means Santarus, Inc., a Delaware
corporation, or any successor corporation thereto.

                  (e)      "CONSULTANT" means any person, including an advisor,
engaged by a Participating Company to render services other than as an Employee
or a Director.

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                  (f)      "DIRECTOR" means a member of the Board or of the
board of directors of any other Participating Company.

                  (g)      "DISABILITY" means the inability of the Optionee, in
the opinion of a qualified physician acceptable to the Company, to perform the
major duties of the Optionee's position with the Participating Company Group
because of the sickness or injury of the Optionee.

                  (h)      "EMPLOYEE" means any person treated as an employee
(including an officer or a Director who is also treated as an employee) in the
records of a Participating Company and, with respect to any Incentive Stock
Option granted to such person, who is an employee for purposes of Section 422 of
the Code; provided, however, that neither service as a Director nor payment of a
Director's fee shall be sufficient to constitute employment for purposes of the
Plan.

                  (i)      "EXCHANGE ACT" means the Securities Exchange Act of
1934, as amended.

                  (j)      "FAIR MARKET VALUE" means, as of any date, the value
of a share of Stock or other property as determined by the Board, in its sole
discretion, or by the Company, in its sole discretion, if such determination is
expressly allocated to the Company herein, subject to the following:

                           (i)      If, on such date, there is a public market
for the Stock, the Fair Market Value of a share of Stock shall be the closing
sale price of a share of Stock (or the mean of the closing bid and asked prices
of a share of Stock if the Stock is so quoted instead) as quoted on the Nasdaq
National Market, the Nasdaq Small-Cap Market or such other national or regional
securities exchange or market system constituting the primary market for the
Stock, as reported in the Wall Street Journal or such other source as the
Company deems reliable. If the relevant date does not fall on a day on which the
Stock has traded on such securities exchange or market system, the date on which
the Fair Market Value shall be established shall be the last day on which the
Stock was so traded prior to the relevant date, or such other appropriate day as
shall be determined by the Board, in its sole discretion.

                           (ii)     If, on such date, there is no public market
for the Stock, the Fair Market Value of a share of Stock shall be as determined
by the Board without regard to any restriction other than a restriction which,
by its terms, will never lapse.

                  (k)      "IMMEDIATE FAMILY" means any child, stepchild,
grandchild, parent, stepparent, grandparent, spouse, former spouse, sibling,
niece, nephew, mother-in-law, father-in-law, son-in law, daughter-in-law,
brother-in-law, or sister-in-law, including adoptive relationships, any person
sharing the Optionee's household (other than a tenant or employee), a trust in
which these persons (or the Optionee) have more than fifty percent (50%) of the
beneficial interest, a foundation in which these persons (or the Optionee)
control the management of assets, and any other entity in which these persons
(or the Optionee) own more than fifty percent (50%) of the voting interests.

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                  (l)      "INCENTIVE STOCK OPTION" means an Option intended to
be (as set forth in the Option Agreement) and which qualifies as an incentive
stock option within the meaning of Section 422(b) of the Code.

                  (m)      "INSIDER" means an officer or a Director of the
Company or any other person whose transactions in Stock are subject to Section
16 of the Exchange Act.

                  (n)      "NONSTATUTORY STOCK OPTION" means an Option which (i)
is not intended to (as set forth in the Option Agreement) or (ii) does not
qualify as an Incentive Stock Option.

                  (o)      "OPTION" means a right to purchase Stock (subject to
adjustment as provided in Section 4.2) pursuant to the terms and conditions of
the Plan. An Option may be either an Incentive Stock Option or a Nonstatutory
Stock Option.

                  (p)      "OPTION AGREEMENT" means a written agreement between
the Company and an Optionee setting forth the terms, conditions and restrictions
of the Option granted to the Optionee and any shares acquired upon the exercise
thereof.

                  (q)      "OPTIONEE" means a person who has been granted one or
more Options.

                  (r)      "PARENT CORPORATION" means any present or future
"parent corporation" of the Company, as defined in Section 424(e) of the Code.

                  (s)      "PARTICIPATING COMPANY" means the Company or any
Parent Corporation or Subsidiary Corporation.

                  (t)      "PARTICIPATING COMPANY GROUP" means, at any point in
time, all corporations collectively which are then Participating Companies.

                  (u)      "RULE 16B-3" means Rule 16b-3 under the Exchange Act,
as amended from time to time, or any successor rule or regulation.

                  (v)      "SECURITIES ACT" means the Securities Act of 1933, as
amended.

                  (w)      "SERVICE" means an Optionee's employment or service
with the Participating Company Group, whether in the capacity of an Employee, a
Director or a Consultant. The Optionee's Service shall not be deemed to have
terminated merely because of a change in the capacity in which the Optionee
renders Service to the Participating Company Group or a change in the
Participating Company for which the Optionee renders such Service, provided that
there is no interruption or termination of the Optionee's Service. Furthermore,
an Optionee's Service with the Participating Company Group shall not be deemed
to have terminated if the Optionee takes any military leave, sick leave, or
other bona fide leave of absence approved by the Company; provided, however,
that if any such leave exceeds ninety (90) days, on the ninety-first (91st) day
of such leave the Optionee's Service shall be deemed to have terminated unless
the Optionee's right to return to Service with the Participating Company Group
is guaranteed by statute or contract. Notwithstanding the foregoing, unless
otherwise designated by the Company or required by law, a leave of absence shall
not be treated as Service for purposes of determining vesting under the
Optionee's Option Agreement. The Optionee's

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Service shall be deemed to have terminated either upon an actual termination of
Service or upon the corporation for which the Optionee performs Service ceasing
to be a Participating Company. Subject to the foregoing, the Company, in its
sole discretion, shall determine whether the Optionee's Service has terminated
and the effective date of such termination.

                  (x)      "STOCK" means the common stock of the Company, as
adjusted from time to time in accordance with Section 4.2.

                  (y)      "SUBSIDIARY CORPORATION" means any present or future
"subsidiary corporation" of the Company, as defined in Section 424(f) of the
Code.

                  (z)      "TEN PERCENT OWNER OPTIONEE" means an Optionee who,
at the time an Option is granted to the Optionee, owns stock possessing more
than ten percent (10%) of the total combined voting power of all classes of
stock of a Participating Company within the meaning of Section 422(b)(6) of the
Code.

         2.2      CONSTRUCTION. Captions and titles contained herein are for
convenience only and shall not affect the meaning or interpretation of any
provision of the Plan. Except when otherwise indicated by the context, the
singular shall include the plural and the plural shall include the singular. Use
of the term "or" is not intended to be exclusive, unless the context clearly
requires otherwise.

3.       ADMINISTRATION.

         3.1      ADMINISTRATION BY THE BOARD. The Plan shall be administered by
the Board. All questions of interpretation of the Plan or of any Option shall be
determined by the Board, and such determinations shall be final and binding upon
all persons having an interest in the Plan or such Option. Any officer of a
Participating Company shall have the authority to act on behalf of the Company
with respect to any matter, right, obligation, determination or election which
is the responsibility of or which is allocated to the Company herein, provided
the officer has apparent authority with respect to such matter, right,
obligation, determination or election.

         3.2      ADMINISTRATION WITH RESPECT TO INSIDERS. With respect to
participation by Insiders in the Plan, at any time that any class of equity
security of the Company is registered pursuant to Section 12 of the Exchange
Act, the Plan shall be administered in compliance with the requirements, if any,
of Rule 16b-3.

         3.3      POWERS OF THE BOARD. In addition to any other powers set forth
in the Plan and subject to the provisions of the Plan, the Board shall have the
full and final power and authority, in its sole discretion to:

                  (a)      determine the persons to whom, and the time or times
at which, Options shall be granted and the number of shares of Stock to be
subject to each Option;

                  (b)      designate Options as Incentive Stock Options or
Nonstatutory Stock Options;

                  (c)      determine the Fair Market Value of shares of Stock or
other property;

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                  (d)      determine the terms, conditions and restrictions
applicable to each Option (which need not be identical) and any shares acquired
upon the exercise thereof, including, without limitation, (i) the exercise price
of the Option, (ii) the method of payment for shares purchased upon the exercise
of the Option, (iii) the method for satisfaction of any tax withholding
obligation arising in connection with the Option or such shares, including by
the withholding or delivery of shares of stock, (iv) the timing, terms and
conditions of the exercisability of the Option or the vesting of any shares
acquired upon the exercise thereof, (v) the time of the expiration of the
Option, (vi) the effect of the Optionee's termination of Service with the
Participating Company Group on any of the foregoing, and (vii) all other terms,
conditions and restrictions applicable to the Option or such shares not
inconsistent with the terms of the Plan;

                  (e)      approve one or more forms of Option Agreement;

                  (f)      amend, modify, extend, cancel, renew, reprice or
otherwise adjust the exercise price of, or grant a new Option in substitution
for, any Option or to waive any restrictions or conditions applicable to any
Option or any shares acquired upon the exercise thereof;

                  (g)      accelerate, continue, extend or defer the
exercisability of any Option or the vesting of any shares acquired upon the
exercise thereof, including with respect to the period following an Optionee's
termination of Service with the Participating Company Group;

                  (h)      prescribe, amend or rescind rules, guidelines and
policies relating to the Plan, or adopt supplements to, or alternative versions
of, the Plan, including, without limitation, as the Board deems necessary or
desirable to comply with the laws of, or to accommodate the tax policy or custom
of, foreign jurisdictions whose citizens may be granted Options; and

                  (i)      correct any defect, supply any omission or reconcile
any inconsistency in the Plan or any Option Agreement and to make all other
determinations and take such other actions with respect to the Plan or any
Option as the Board may deem advisable to the extent consistent with the Plan
and applicable law.

4.       SHARES SUBJECT TO PLAN.

         4.1      MAXIMUM NUMBER OF SHARES ISSUABLE. Subject to adjustment as
provided in Section 4.2, the maximum aggregate number of shares of Stock that
may be issued under the Plan shall be Fourteen Million Six Hundred Thousand
(14,600,000) and shall consist of authorized but unissued or reacquired shares
of Stock or any combination thereof. If an outstanding Option for any reason
expires or is terminated or canceled or shares of Stock acquired, subject to
repurchase, upon the exercise of an Option are repurchased by the Company, the
shares of Stock allocable to the unexercised portion of such Option, or such
repurchased shares of Stock, shall again be available for issuance under the
Plan. Notwithstanding the foregoing, at any such time as the offer and sale of
securities pursuant to the Plan is subject to compliance with Section 260.140.45
of Title 10 of the California Code of Regulations ("SECTION 260.140.45"), the
total number of shares of Stock issuable upon the exercise of all outstanding
Options (together with options outstanding under any other stock option plan of
the Company)

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and the total number of shares provided for under any stock bonus or similar
plan of the Company shall not exceed thirty percent (30%) (or such other higher
percentage limitation as may be approved by the shareholders of the Company
pursuant to Section 260.140.45) of the then outstanding shares of the Company as
calculated in accordance with the conditions and exclusions of Section
260.140.45.

         4.2      ADJUSTMENTS FOR CHANGES IN CAPITAL STRUCTURE. In the event of
any stock dividend, stock split, reverse stock split, recapitalization,
combination, reclassification or similar change in the capital structure of the
Company, appropriate adjustments shall be made in the number and class of shares
subject to the Plan and to any outstanding Options and in the exercise price per
share of any outstanding Options. If a majority of the shares which are of the
same class as the shares that are subject to outstanding Options are exchanged
for, converted into, or otherwise become (whether or not pursuant to an
Ownership Change Event, as defined in Section 8.1) shares of another
corporation, the Board may unilaterally amend the outstanding Options to provide
that such Options are exercisable for such shares. In the event of any such
amendment, the number of shares subject to, and the exercise price per share of,
the outstanding Options shall be adjusted in a fair and equitable manner as
determined by the Board, in its sole discretion. Notwithstanding the foregoing,
any fractional share resulting from an adjustment pursuant to this Section 4.2
shall be rounded up or down to the nearest whole number, as determined by the
Board, and in no event may the exercise price of any Option be decreased to an
amount less than the par value, if any, of the stock subject to the Option. The
adjustments determined by the Board pursuant to this Section 4.2 shall be final,
binding and conclusive.

5.       ELIGIBILITY AND OPTION LIMITATIONS.

         5.1      PERSONS ELIGIBLE FOR OPTIONS. Options may be granted only to
Employees, Consultants, and Directors. For purposes of the foregoing sentence,
"EMPLOYEES," "CONSULTANTS" and "DIRECTORS" shall include prospective Employees,
prospective Consultants and prospective Directors to whom Options are granted in
connection with written offers of an employment or other service relationship
with the Participating Company Group. Eligible persons may be granted more than
one (1) Option.

         5.2      OPTION GRANT RESTRICTIONS. Any person who is not an Employee
on the effective date of the grant of an Option to such person may be granted
only a Nonstatutory Stock Option. An Incentive Stock Option granted to a
prospective Employee upon the condition that such person become an Employee
shall be deemed granted effective on the date such person commences Service with
a Participating Company, with an exercise price determined as of such date in
accordance with Section 6.1.

         5.3      FAIR MARKET VALUE LIMITATION. To the extent that options
designated as Incentive Stock Options (granted under all stock option plans of
the Participating Company Group, including the Plan) become exercisable by an
Optionee for the first time during any calendar year for stock having a Fair
Market Value greater than One Hundred Thousand Dollars ($100,000), the portion
of such options which exceeds such amount shall be treated as Nonstatutory Stock
Options. For purposes of this Section 5.3, options designated as Incentive Stock
Options shall be taken into account in the order in which they were granted, and
the Fair Market Value of stock shall be determined as of the time the option
with respect to such stock is

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granted. If the Code is amended to provide for a different limitation from that
set forth in this Section 5.3, such different limitation shall be deemed
incorporated herein effective as of the date and with respect to such Options as
required or permitted by such amendment to the Code. If an Option is treated as
an Incentive Stock Option in part and as a Nonstatutory Stock Option in part by
reason of the limitation set forth in this Section 5.3, the Optionee may
designate which portion of such Option the Optionee is exercising. In the
absence of such designation, the Optionee shall be deemed to have exercised the
Incentive Stock Option portion of the Option first. Separate certificates
representing each such portion shall be issued upon the exercise of the Option.

6.       TERMS AND CONDITIONS OF OPTIONS.

         Options shall be evidenced by Option Agreements specifying the number
of shares of Stock covered thereby, in such form as the Board shall from time to
time establish. No Option or purported Option shall be a valid and binding
obligation of the Company unless evidenced by a fully executed Option Agreement.
Option Agreements may incorporate all or any of the terms of the Plan by
reference and shall comply with and be subject to the following terms and
conditions:

         6.1      EXERCISE PRICE. The exercise price for each Option shall be
established in the sole discretion of the Board; provided, however, that (a) the
exercise price per share for an Incentive Stock Option shall be not less than
the Fair Market Value of a share of Stock on the effective date of grant of the
Option, (b) the exercise price per share for a Nonstatutory Stock Option shall
be not less than eighty-five percent (85%) of the Fair Market Value of a share
of Stock on the effective date of grant of the Option, and (c) no Option granted
to a Ten Percent Owner Optionee shall have an exercise price per share less than
one hundred ten percent (110%) of the Fair Market Value of a share of Stock on
the effective date of grant of the Option. Notwithstanding the foregoing, an
Option (whether an Incentive Stock Option or a Nonstatutory Stock Option) 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 provisions of Section 424(a) of
the Code.

         6.2      EXERCISE PERIOD. Options shall be exercisable at such time or
times, or upon such event or events, and subject to such terms, conditions,
performance criteria, and restrictions as shall be determined by the Board and
set forth in the Option Agreement evidencing such Option; provided, however,
that (a) no Option shall be exercisable after the expiration of ten (10) years
after the effective date of grant of such Option, (b) no Incentive Stock Option
granted to a Ten Percent Owner Optionee shall be exercisable after the
expiration of five (5) years after the effective date of grant of such Option,
(c) no Option granted to a prospective Employee, prospective Consultant or
prospective Director may become exercisable prior to the date on which such
person commences Service with a Participating Company, and (d) with the
exception of an Option granted to an officer, Director or Consultant, no Option
shall become exercisable at a rate less than twenty percent (20%) per year over
a period of five (5) years from the effective date of grant of such Option,
subject to the Optionee's continued Service. Subject to the foregoing, unless
otherwise specified by the Board in the grant of an Option, any Option granted
hereunder shall have a term of ten (10) years from the effective date of grant
of the Option.

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         6.3      PAYMENT OF EXERCISE PRICE.

                  (a)      FORMS OF CONSIDERATION AUTHORIZED. Except as
otherwise provided below, payment of the exercise price for the number of shares
of Stock being purchased pursuant to any Option shall be made (i) in cash, by
check, or cash equivalent, (ii) by tender to the Company of shares of Stock
owned by the Optionee having a Fair Market Value (as determined by the Company
without regard to any restrictions on transferability applicable to such stock
by reason of federal or state securities laws or agreements with an underwriter
for the Company) not less than the exercise price, (iii) by the assignment of
the proceeds of a sale or loan (a "CASHLESS EXERCISE") with respect to some or
all of the shares being acquired upon the exercise of the Option (including,
without limitation, through an exercise complying with the provisions of
Regulation T as promulgated from time to time by the Board of Governors of the
Federal Reserve System), (iv) by the Optionee's promissory note in a form
approved by the Company, (v) by such other consideration as may be approved by
the Board from time to time to the extent permitted by applicable law, or (vi)
by any combination thereof. The Board may at any time or from time to time, by
adoption of or by amendment to the standard forms of Option Agreement described
in Section 7, or by other means, grant Options which do not permit all of the
foregoing forms of consideration to be used in payment of the exercise price or
which otherwise restrict one or more forms of consideration.

                  (b)      TENDER OF STOCK. Notwithstanding the foregoing, an
Option may not be exercised by tender to the Company of shares of Stock to the
extent such tender of Stock would constitute a violation of the provisions of
any law, regulation or agreement restricting the redemption of the Company's
stock. Unless otherwise provided by the Board, an Option may not be exercised by
tender to the Company of shares of Stock unless such shares either have been
owned by the Optionee for more than six (6) months or were not acquired,
directly or indirectly, from the Company.

                  (c)      CASHLESS EXERCISE. The Company reserves, at any and
all times, the right, in the Company's sole and absolute discretion, to
establish, decline to approve or terminate any program or procedures for the
exercise of Options by means of a Cashless Exercise.

                  (d)      PAYMENT BY PROMISSORY NOTE. No promissory note shall
be permitted if the exercise of an Option using a promissory note would be a
violation of any law. Any permitted promissory note shall be on such terms as
the Board shall determine. The Board shall have the authority to permit or
require the Optionee to secure any promissory note used to exercise an Option
with the shares of Stock acquired upon the exercise of the Option or with other
collateral acceptable to the Company. Unless otherwise provided by the Board, if
the Company at any time is subject to the regulations promulgated by the Board
of Governors of the Federal Reserve System or any other governmental entity
affecting the extension of credit in connection with the Company's securities,
any promissory note shall comply with such applicable regulations, and the
Optionee shall pay the unpaid principal and accrued interest, if any, to the
extent necessary to comply with such applicable regulations.

         6.4      TAX WITHHOLDING. The Company shall have the right, but not the
obligation, to deduct from the shares of Stock issuable upon the exercise of an
Option, or to accept from the Optionee the tender of, a number of whole shares
of Stock having a Fair Market Value, as

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determined by the Company, equal to all or any part of the federal, state, local
and foreign taxes, if any, required by law to be withheld by the Participating
Company Group with respect to such Option or the shares acquired upon the
exercise thereof. Alternatively or in addition, in its sole discretion, the
Company shall have the right to require the Optionee, through payroll
withholding, cash payment or otherwise, including by means of a Cashless
Exercise, to make adequate provision for any such tax withholding obligations of
the Participating Company Group arising in connection with the Option or the
shares acquired upon the exercise thereof. The Company shall have no obligation
to deliver shares of Stock or to release shares of Stock from an escrow
established pursuant to the Option Agreement until the Participating Company
Group's tax withholding obligations have been satisfied by the Optionee.

         6.5      REPURCHASE RIGHTS. Shares issued under the Plan may be subject
to a right of first refusal, one or more repurchase options, or other conditions
and restrictions as determined by the Board in its sole discretion at the time
the Option is granted. The Company shall have the right to assign at any time
any repurchase right it may have, whether or not such right is then exercisable,
to one or more persons as may be selected by the Company. Upon request by the
Company, each Optionee shall execute any agreement evidencing such transfer
restrictions prior to the receipt of shares of Stock hereunder and shall
promptly present to the Company any and all certificates representing shares of
Stock acquired hereunder for the placement on such certificates of appropriate
legends evidencing any such transfer restrictions.

         6.6      EFFECT OF TERMINATION OF SERVICE.

                  (a)      OPTION EXERCISABILITY. Subject to earlier termination
of the Option as otherwise provided herein, an Option shall be exercisable after
an Optionee's termination of Service as follows:

                           (i)      DISABILITY. If the Optionee's Service with
the Participating Company Group is terminated because of the Disability of the
Optionee, the Option, to the extent unexercised and exercisable on the date on
which the Optionee's Service terminated, may be exercised by the Optionee (or
the Optionee's guardian or legal representative) at any time prior to the
expiration of six (6) months (or such longer period of time as determined by the
Board, in its sole discretion) after the date on which the Optionee's Service
terminated, but in any event no later than the date of expiration of the
Option's term as set forth in the Option Agreement evidencing such Option (the
"OPTION EXPIRATION DATE").

                           (ii)     DEATH. If the Optionee's Service with the
Participating Company Group is terminated because of the death of the Optionee,
the Option, to the extent unexercised and exercisable on the date on which the
Optionee's Service terminated, may be exercised by the Optionee's legal
representative or other person who acquired the right to exercise the Option by
reason of the Optionee's death at any time prior to the expiration of six (6)
months (or such longer period of time as determined by the Board, in its sole
discretion) after the date on which the Optionee's Service terminated, but in
any event no later than the Option Expiration Date. The Optionee's Service shall
be deemed to have terminated on account of death if the Optionee dies within one
(1) month after the Optionee's termination of Service.

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                           (iii)    OTHER TERMINATION OF SERVICE. If the
Optionee's Service with the Participating Company Group terminates for any
reason, except Disability or death, the Option, to the extent unexercised and
exercisable by the Optionee on the date on which the Optionee's Service
terminated, may be exercised by the Optionee within one (1) month (or such
longer period of time as determined by the Board, in its sole discretion) after
the date on which the Optionee's Service terminated, but in any event no later
than the Option Expiration Date.

                  (b)      EXTENSION IF EXERCISE PREVENTED BY LAW.
Notwithstanding the foregoing, if the exercise of an Option within the
applicable time periods set forth in this Section 6.6 is prevented by the
provisions of Section 11 below, the Option shall remain exercisable until one
(1) month after the date the Optionee is notified by the Company that the Option
is exercisable, but in any event no later than the Option Expiration Date.

                  (c)      EXTENSION IF OPTIONEE SUBJECT TO SECTION 16(b).
Notwithstanding the foregoing, if a sale within the applicable time periods set
forth in this Section 6.6 of shares acquired upon the exercise of the Option
would subject the Optionee to suit under Section 16(b) of the Exchange Act, the
Option shall remain exercisable until the earliest to occur of (i) the tenth
(10th) day following the date on which a sale of such shares by the Optionee
would no longer be subject to such suit, (ii) the one hundred and ninetieth
(190th) day after the Optionee's termination of Service, or (iii) the Option
Expiration Date.

7.       STANDARD FORMS OF OPTION AGREEMENT.

         7.1      INCENTIVE STOCK OPTIONS. Unless otherwise provided by the
Board at the time the Option is granted, an Option designated as an "INCENTIVE
STOCK OPTION" shall comply with and be subject to the terms and conditions set
forth in the form of Incentive Stock Option Agreement adopted by the Board
concurrently with its adoption of the Plan and as amended from time to time.

         7.2      NONSTATUTORY STOCK OPTIONS. Unless otherwise provided by the
Board at the time the Option is granted, an Option designated as a "NONSTATUTORY
STOCK OPTION" shall comply with and be subject to the terms and conditions set
forth in the form of Nonstatutory Stock Option Agreement adopted by the Board
concurrently with its adoption of the Plan and as amended from time to time.

         7.3      AUTHORITY TO VARY TERMS. The Board shall have the authority
from time to time to vary the terms of any of the standard forms of Option
Agreement described in this Section 7 either in connection with the grant or
amendment of an individual Option or in connection with the authorization of a
new standard form or forms; provided, however, that the terms and conditions of
any such new, revised or amended standard form or forms of Option Agreement
shall be in accordance with the terms of the Plan.

8.       CHANGE IN CONTROL.

         8.1      DEFINITIONS.

                  (a)      An "OWNERSHIP CHANGE EVENT" shall be deemed to have
occurred if any of the following occurs with respect to the Company:

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                           (i)      the direct or indirect sale or exchange in a
single or series of related transactions by the shareholders of the Company of
more than fifty percent (50%) of the voting stock of the Company;

                           (ii)     a merger or consolidation in which the
Company is a party;

                           (iii)    the sale, exchange, or transfer of all or
substantially all of the assets of the Company; or

                           (iv)     a liquidation or dissolution of the Company.

                  (b)      A "CHANGE IN CONTROL" shall mean an Ownership Change
Event or a series of related Ownership Change Events (collectively, the
"TRANSACTION") wherein the shareholders of the Company immediately before the
Transaction do not retain immediately after the Transaction, in substantially
the same proportions as their ownership of shares of the Company's voting stock
immediately before the Transaction, direct or indirect beneficial ownership of
more than fifty percent (50%) of the total combined voting power of the
outstanding voting stock of the Company or the corporation or corporations to
which the assets of the Company were transferred (the "TRANSFEREE
CORPORATION(S)"), as the case may be. For purposes of the preceding sentence,
indirect beneficial ownership shall include, without limitation, an interest
resulting from ownership of the voting stock of one or more corporations which,
as a result of the Transaction, own the Company or the Transferee
Corporation(s), as the case may be, either directly or through one or more
subsidiary corporations. The Board shall have the right to determine whether
multiple sales or exchanges of the voting stock of the Company or multiple
Ownership Change Events are related, and its determination shall be final,
binding and conclusive.

         8.2      EFFECT OF CHANGE IN CONTROL.

                  (a)      In the event of a Change in Control, the surviving,
continuing, successor, or purchasing corporation or parent or subsidiary
corporation thereof, as the case may be (the "ACQUIRING CORPORATION"), may
either (i) assume the Company's rights and obligations under outstanding
Options, (ii) substitute for outstanding Options substantially equivalent
options for the Acquiring Corporation's stock, or (iii) do none of the above.
For purposes of this Section 8.2, an Option shall be deemed assumed if,
following the Change in Control, the Option confers the right to purchase in
accordance with its terms and conditions, for each share of Stock subject to the
Option immediately prior to the Change in Control, the consideration (whether
stock, cash or other securities or property) to which a holder of a share of
Stock on the effective date of the Change in Control was entitled.

                  (b)      In the event of a Change in Control where the
Company's repurchase rights with respect to unvested, exercised option shares
will NOT be assigned to or otherwise continued in effect by the Acquiring
Corporation, one hundred percent (100%) of any outstanding repurchase rights
applicable to any unvested, exercised option shares shall terminate
automatically, and the shares of Stock subject to those terminated rights shall
automatically become vested shares immediately prior to the consummation of the
Change in Control.

                                       11
<PAGE>

                  (c)      In the event of a Change in Control where the
outstanding Options will NOT be assumed or substituted by the Acquiring
Corporation as provided in Section 8.2(a) above, and provided that the
Optionee's Service has not terminated prior to such date, one hundred percent
(100%) of any unexercisable or unvested portion of each of any outstanding
unexercised Options shall become automatically exercisable and vested as of the
date ten (10) days prior to the date of the Change in Control.

                  (d)      In the event of a Change in Control where the
outstanding Options will be assumed or substituted by the Acquiring Corporation
as provided in Section 8.2(a) above, and provided that the Optionee's Service
has not terminated prior to such date, (i) 50% of any outstanding repurchase
rights applicable to any unvested, exercised option shares (determined as of the
date ten (10) days prior to the date of the Change in Control) shall terminate
automatically, and the shares of Stock subject to those terminated rights shall
automatically become vested shares immediately prior to the consummation of the
Change in Control and (ii) fifty percent (50%) of any unexercisable or unvested
portion of each of any outstanding, unexercised Options (determined as of the
date ten (10) days prior to the date of the Change in Control) shall become
automatically immediately exercisable and vested as of the date ten (10) days
prior to the date of the Change in Control.

                  (e)      Notwithstanding the foregoing, if any Option had
previously been partially exercised such that an unexercised portion of the
Option still remains outstanding as of the date ten (10) days prior to the date
of the Change in Control, the 50% vesting acceleration provisions of Section
8.2(d) above shall be applied to the total number of shares subject to such
Option that consist of (i) then unvested exercised shares that were previously
acquired upon the partial exercise of such Option plus (ii) the remaining
unvested unexercised Option shares. The 50% acceleration of vesting shall be
first applied toward the unvested previously exercised option shares such that
no unexercised Option shares shall vest on an accelerated basis in accordance
with the provisions of Section 8.2(d) unless and until all the unvested
exercised shares subject to such Option have first vested.

                  (f)      The exercise or vesting of any Option or exercised
option shares that was permissible solely by reason of this Section 8.2 shall be
conditioned upon the consummation of the Change in Control. Any Options which
are neither assumed or substituted for by the Acquiring Corporation in
connection with the Change in Control nor exercised as of the date of the Change
in Control shall terminate and cease to be outstanding effective as of the date
of the Change in Control. To the extent any Option shall continue in effect
following a Change in Control, it shall continue to be subject to all applicable
provisions of the Option Agreement evidencing such Option except as otherwise
provided in such Option Agreement. Shares acquired upon exercise of an Option
prior to the Change in Control shall continue to be subject to all applicable
provisions of the Option Agreement except as otherwise provided in such Option
Agreement.

         8.3      EFFECT OF TERMINATION FOLLOWING CHANGE IN CONTROL.

                  (a)      In the event of a Change in Control where the Options
will be assumed or substituted as provided in Section 8.2(a) above such that
only 50% of the Option shares and/or unvested previously exercised shares will
accelerate in connection with a Change in Control,

                                       12
<PAGE>

then those remaining unvested Option shares shall become immediately vested and
exercisable and the remaining repurchase rights applicable to such exercised
unvested shares will also terminate automatically, and the unvested shares of
Stock subject to those terminated rights shall immediately become vested shares,
if within twelve (12) months following such Change in Control (i) the Optionee's
service relationship with the Acquiring Corporation is terminated by the
Acquiring Corporation without "cause," or (ii) such Optionee voluntarily quits
with "good reason." In either case, the Option will remain exercisable until the
earlier of the expiration date of such Option or three (3) months following such
Optionee's cessation of service.

                  (b)      A resignation by an Optionee that is for "good
reason" shall mean such Optionee's voluntary resignation following any one or
more of the following that is effected without the Optionee's written consent:
(i) a change in his or her position following the Change in Control that
materially reduces his or her duties or responsibilities, (ii) a reduction in
his or her base salary following the Change in Control, unless the base salaries
of all similarly situated individuals are similarly reduced by the Acquiring
Corporation employing the Optionee or (iii) a relocation of such Optionee's
place of employment of more than fifty (50) miles following the Change in
Control.

                  (c)      The term "cause" shall include any one or more of the
following: (i) the commission of any act of fraud, embezzlement or dishonesty by
such Optionee that has a material adverse impact on the Acquiring Corporation,
(ii) a conviction of, or a plea of "guilty" or "no contest" to, a felony by such
Optionee, (iii) any unauthorized use or disclosure by such Optionee of
confidential information or trade secrets of the Acquiring Corporation
(including confidential information or trade secrets of the Corporation) that
has a material adverse impact on the Acquiring Corporation, or (iv) any other
intentional misconduct by such Optionee that has a material adverse impact on
the Acquiring Corporation. However, if the term or concept has been defined in
an employment agreement between the Acquiring Corporation and the Optionee, then
"cause" shall have the definition set forth in such employment agreement. The
foregoing definition shall not in any way preclude or restrict the right of the
Acquiring Corporation to discharge or dismiss any Optionee in the service of the
Acquiring Corporation for any other acts or omissions, but such other acts or
omissions shall not be deemed, for purposes of the Plan, to constitute grounds
for termination for cause.

         8.4      BOARD DISCRETION. Notwithstanding the foregoing, the Board
shall have the discretion to grant Options with terms that are more favorable to
Optionees relating to the effect of a Change in Control on such Options than
those set forth in this Section 8. Any such terms shall be set forth in the form
of Option Agreement evidencing the grant of such Options.

9.       PROVISION OF INFORMATION.

         At least annually, copies of the Company's balance sheet and income
statement for the just completed fiscal year shall be made available to each
Optionee and purchaser of shares of Stock upon the exercise of an Option. The
Company shall not be required to provide such information to persons whose
duties in connection with the Company assure them access to equivalent
information.

                                       13
<PAGE>

10.      TRANSFERABILITY OF OPTIONS.

         Nonstatutory Stock Options shall be transferable (i) by will or by the
laws of descent and distribution or (ii) to the extent and in the manner
authorized by the Board by gift or pursuant to a domestic relations order to
members of the Optionee's Immediate Family. Incentive Stock Options may not be
sold, pledged, assigned, hypothecated, transferred, or disposed of in any manner
other than by will or by the laws of descent or distribution and may be
exercised, during the lifetime of the Optionee, only by the Optionee or the
Optionee's guardian or legal representative. Notwithstanding the foregoing, the
Optionee may designate one or more beneficiaries of the Optionee's Incentive
Stock Option or Nonstatutory Stock Option in the event of the Optionee's death
on a beneficiary designation form provided by the Board.

11.      COMPLIANCE WITH SECURITIES LAW.

         The grant of Options and the issuance of shares of Stock upon exercise
of Options shall be subject to compliance with all applicable requirements of
federal, state and foreign law with respect to such securities. Options may not
be exercised if the issuance of shares of Stock upon exercise would constitute a
violation of any applicable federal, state or foreign securities laws or other
law or regulations or the requirements of any stock exchange or market system
upon which the Stock may then be listed. In addition, no Option may be exercised
unless (a) a registration statement under the Securities Act shall at the time
of exercise of the Option be in effect with respect to the shares issuable upon
exercise of the Option or (b) in the opinion of legal counsel to the Company,
the shares issuable upon exercise of the Option may be issued in accordance with
the terms of an applicable exemption from the registration requirements of the
Securities Act. The inability of the Company to obtain from any regulatory body
having jurisdiction the authority, if any, deemed by the Company's legal counsel
to be necessary to the lawful issuance and sale of any shares hereunder shall
relieve the Company of any liability in respect of the failure to issue or sell
such shares as to which such requisite authority shall not have been obtained.
As a condition to the exercise of any Option, the Company may require the
Optionee to satisfy any qualifications that may be necessary or appropriate, to
evidence compliance with any applicable law or regulation and to make any
representation or warranty with respect thereto as may be requested by the
Company.

12.      INDEMNIFICATION.

         In addition to such other rights of indemnification as they may have as
members of the Board or officers or employees of the Participating Company
Group, members of the Board and any officers or employees of the Participating
Company Group to whom authority to act for the Board or the Company is delegated
shall be indemnified by the Company against all reasonable expenses, including
attorneys' fees, actually and necessarily incurred in connection with the
defense of any action, suit or proceeding, or in connection with any appeal
therein, to which they or any of them may be a party by reason of any action
taken or failure to act under or in connection with the Plan, or any right
granted hereunder, and against all amounts paid by them in settlement thereof
(provided such settlement is approved by independent legal counsel selected by
the Company) or paid by them in satisfaction of a judgment in any such action,
suit or proceeding, except in relation to matters as to which it shall be
adjudged in such action, suit or proceeding that such person is liable for gross
negligence, bad faith or intentional misconduct in

                                       14
<PAGE>

duties; provided, however, that within sixty (60) days after the institution of
such action, suit or proceeding, such person shall offer to the Company, in
writing, the opportunity at its own expense to handle and defend the same.

13.      TERMINATION OR AMENDMENT OF PLAN.

         The Board may terminate or amend the Plan at any time. However, subject
to changes in applicable law, regulations or rules that would permit otherwise,
without the approval of the Company's shareholders, there shall be (a) no
increase in the maximum aggregate number of shares of Stock that may be issued
under the Plan (except by operation of the provisions of Section 4.2), (b) no
change in the class of persons eligible to receive Incentive Stock Options, and
(c) no other amendment of the Plan that would require approval of the Company's
shareholders under any applicable law, regulation or rule. In any event, no
termination or amendment of the Plan may adversely affect any then outstanding
Option or any unexercised portion thereof, without the consent of the Optionee,
unless such termination or amendment is required to enable an Option designated
as an Incentive Stock Option to qualify as an Incentive Stock Option or is
necessary to comply with any applicable law, regulation or rule.

14.      SHAREHOLDER APPROVAL.

         The Plan or any increase in the maximum number of shares of Stock
issuable thereunder as provided in Section 4.1 (the "MAXIMUM SHARES") shall be
approved by the shareholders of the Company within twelve (12) months of the
date of adoption thereof by the Board. Options granted prior to shareholder
approval of the Plan or in excess of the Maximum Shares previously approved by
the shareholders shall become exercisable no earlier than the date of
shareholder approval of the Plan or such increase in the Maximum Shares, as the
case may be.

         IN WITNESS WHEREOF, the undersigned Secretary of the Company certifies
that the foregoing Santarus, Inc. 1998 Stock Option Plan was duly adopted by the
Board on October 30, 1998, and by the shareholders on November 5, 1998, revised
by the Board on June 16, 2000, and by the shareholders on August 27, 2000,
revised by the Board on February 21, 2001 and by the shareholders on February
21, 2001, revised by the Board on October 10, 2001, revised by the Board on
January 14, 2002, and by the shareholders on January 14, 2002, revised by the
Board on March 19, 2002, revised by the Board on March 5, 2003, and by the
shareholders on March 6, 2003, revised by the Board on December 3, 2003.

                                                      /s/ Debra P. Crawford
                                                     ---------------------------
                                                     Debra P. Crawford,
                                                     Secretary

                                       15
<PAGE>

                                  PLAN HISTORY

October 30, 1998           Board adopts Plan, with an initial reserve of
                           1,000,000 shares.

November 5, 1998           Shareholders approve Plan, with an initial reserve of
                           1,000,000 shares.

June 16, 2000              Board approves increase in share reserve from
                           1,000,000 to 1,600,000.

August 27, 2000            Shareholders approve increase in share reserve from
                           1,000,000 to 1,600,000.

February 21, 2001          Board approves increase in share reserve from
                           1,600,000 to 3,750,000.

February 21, 2001          Shareholders approve increase in share reserve from
                           1,600,000 to 3,750,000.

October 10, 2001           Board approves increase in share reserve form
                           3,750,000 to 4,600,000.

January 14, 2002           Board approves modification to allow the Board
                           flexibility in the determination of the terms of
                           promissory notes delivered as payment for the
                           exercise of options.

January 14, 2002           Shareholders approve increase in share reserve from
                           3,750,000 to 4,600,000.

March 19, 2002             Board approves modifications to the default
                           provisions relating to the effect of a Change in
                           Control on outstanding options and exercised shares
                           and expressly granting the Board increased
                           flexibility in determining such terms at the time of
                           option grant.

March 5, 2003              Board approves increase in share reserve from
                           4,600,000 to 14,600,000, effective immediately
                           subsequent to the closing of the first sale of the
                           Company's Series D Preferred Stock (which sale was
                           completed on April 30, 2003).

March 6, 2003              Shareholders approve increase in share reserve from
                           4,600,000 to 14,600,000, effective immediately
                           subsequent to the closing of the first sale of the
                           Company's Series D Preferred Stock (which sale was
                           completed on April 30, 2003).

December 3, 2003           Board approves amendment and restatement of the Plan
                           to permit (a) the transfer of Nonstatutory Stock
                           Options and (b) the designation of beneficiaries for
                           both Incentive Stock Options and Nonstatutory Stock
                           Options.