Exhibit 10.9

LEXICON PHARMACEUTICALS, INC.
2017 NON-EMPLOYEE DIRECTORS’ EQUITY INCENTIVE PLAN

This Plan initially was established as the 2000 Non-Employee Directors’ Stock
Option Plan, effective as of April 12, 2000 (the “2000 Non-Employee Directors’
Stock Option Plan”) which was adopted by the Board on February 3, 2000 and
approved by the Company’s stockholders on March 15, 2000. The 2000 Non-Employee
Directors’ Stock Option Plan, as amended, was subsequently amended and restated
in its entirety and renamed the Non-Employee Directors’ Stock Option Plan (the
“Non-Employee Directors’ Stock Option Plan”), which was adopted by the Board on
February 27, 2009 and approved by the Company’s stockholders on April 23, 2009.
A subsequent amendment to the Non-Employee Directors’ Stock Option Plan pursuant
to which it was renamed the Non-Employee Directors’ Equity Incentive Plan (the
“Non-Employee Directors’ Equity Incentive Plan”) was adopted by the Board on
February 16, 2012 and approved by the Company’s stockholders on April 26, 2012.
The Non-Employee Directors’ Equity Incentive Plan, as amended, was subsequently
amended and restated in its entirety and renamed the 2017 Non-Employee
Directors’ Equity Incentive Plan, which was adopted by the Board on February 9,
2017 and approved by the Company’s stockholders on April 27, 2017. The terms of
this Plan shall supersede the terms of the 2000 Non-Employee Directors’ Stock
Option Plan, Non-Employee Directors’ Stock Option Plan and Non-Employee
Directors’ Equity Incentive Plan in their entirety.

1.    PURPOSES.

(a)    ELIGIBLE STOCK AWARD RECIPIENTS. The persons eligible to receive Stock
Awards are the Non-Employee Directors of the Company.

(b)    AVAILABLE STOCK AWARDS. The purpose of the Plan is to provide a means by
which Non-Employee Directors may be given an opportunity to benefit from
increases in value of the Common Stock through the granting of the following
Stock Awards: (i) Nonstatutory Stock Options, (ii) Restricted Stock Awards and
(iii) Restricted Stock Unit Awards.

(c)    GENERAL PURPOSE. The Company, by means of the Plan, seeks to retain the
services of its Non-Employee Directors, to secure and retain the services of new
Non-Employee Directors and to provide incentives for such persons to exert
maximum efforts for the success of the Company and its Affiliates.

2.    DEFINITIONS.

(a)    “AFFILIATE” means any parent corporation or subsidiary corporation of the
Company, whether now or hereafter existing, as those terms are defined in
Sections 424(e) and (f), respectively, of the Code.

(b)    “BOARD” means the Board of Directors of the Company.

(c)    “CODE” means the Internal Revenue Code of 1986, as amended.

(d)    “COMMON STOCK” means the common stock, par value $.001 per share, of the
Company.

(e)    “COMPANY” means Lexicon Pharmaceuticals, Inc., a Delaware corporation.

(f)    “CONSULTANT” means any person other than a Director or Employee who is
engaged by the Company or an Affiliate to render consulting or advisory services
and who is compensated for such services.

(g)    “CONTINUOUS SERVICE” means that the Participant’s service with the
Company or an Affiliate, whether as an Employee, Director or Consultant, is not
interrupted or terminated. The Participant’s Continuous Service shall not be
deemed to have terminated merely because of a change in the capacity in which
the Participant renders service to the Company or an Affiliate as an Employee,
Consultant or Director or a change in the entity for which the Participant
renders such service, provided that there is no interruption or termination of
the Participant’s Continuous Service. For example, a change in status from a
Non-Employee Director of the Company to a Consultant of an Affiliate or an
Employee of the Company will not constitute an interruption of Continuous
Service. The Board or the chief executive officer of the Company, in that
party’s sole discretion, may determine whether Continuous Service shall be
considered interrupted in the case of any leave of absence approved by that
party, including sick leave, military leave or any other personal leave.

(h)    “DIRECTOR” means a member of the Board of Directors of the Company.

(i)    “DISABILITY” means the permanent and total disability of a person within
the meaning of Section 22(e)(3) of the Code.

(j)    “EMPLOYEE” means any person employed by the Company or an Affiliate. Mere
service as a Director or payment of a director’s fee by the Company or an
Affiliate shall not be sufficient to constitute “employment” by the Company or
an Affiliate.

(k)    “EXCHANGE ACT” means the Securities Exchange Act of 1934, as amended.

(l)    “FAIR MARKET VALUE” means, as of any date, the value of the Common Stock
determined as follows:

(i)    If the Common Stock is listed on any established stock exchange or traded
on the Nasdaq Stock Market, the Fair Market Value of a share of Common Stock
shall be the closing sales price for such stock (or the closing bid, if no sales
were reported) as quoted on such exchange or market (or the exchange or market
with the greatest volume of trading in the Common Stock) on the last market
trading day prior to the day of determination, as reported in The Wall Street
Journal or such other source as the Board deems reliable.

(ii)    In the absence of such markets for the Common Stock, the Fair Market
Value shall be determined in good faith by the Board in such manner as it deems
appropriate and as is consistent with the requirements of section 409A of the
Code.

(m)    “NON-EMPLOYEE DIRECTOR” means a Director who is not an Employee.

(n)    “NONSTATUTORY STOCK OPTION” means an option to purchase Common Stock that
is not intended to qualify as an incentive stock option within the meaning of
Section 422 of the Code and the regulations promulgated thereunder.

(o)    “OPTION” means a Nonstatutory Stock Option to purchase Common Stock
granted pursuant to Section 6 of the Plan.

(p)    “PARTICIPANT” means any Non-Employee Director to whom a Stock Award is
granted pursuant to the Plan.

(q)    “PLAN” means this Lexicon Pharmaceuticals, Inc. 2017 Non-Employee
Directors’ Equity Incentive Plan.

(r)    “RESTRICTED STOCK AWARD” means a right to receive restricted Common Stock
granted pursuant to Section 7(a) of the Plan.

(s)    “RESTRICTED STOCK UNIT AWARD” means a right to receive shares of Common
Stock (or a cash payment equal to the Fair Market Value thereof) granted
pursuant to Section 7(b) of the Plan.

(t)    “RULE 16B-3” means Rule 16b-3 promulgated under the Exchange Act or any
successor to Rule 16b-3, as in effect from time to time.

(u)    “SECURITIES ACT” means the Securities Act of 1933, as amended.

(v)    “STOCK AWARD” means any right granted under the Plan, including an
Option, a Restricted Stock Award or a Restricted Stock Unit Award.

(w)    “STOCK AWARD AGREEMENT” means a written agreement between the Company and
a holder of a Stock Award evidencing the terms and conditions of an individual
Stock Award grant. Each Stock Award Agreement shall be subject to the terms and
conditions of the Plan.

3.    ADMINISTRATION.

(a)    ADMINISTRATION BY BOARD. The Board shall administer the Plan. The Board
may not delegate administration of the Plan to a committee.

(b)    POWERS OF BOARD. The Board shall have the power, subject to, and within
the limitations of, the express provisions of the Plan:

(i)    To determine from time to time which of the Non-Employee Directors shall
be granted Stock Awards; when and how each Stock Award shall be granted; what
type or combination of types of Stock Award shall be granted; the provisions of
each Stock Award granted (which need not be identical), including the time or
times when a Non-Employee Director shall be permitted to receive Common Stock
pursuant to a Stock Award; and the number of shares of Common Stock with respect
to which a Stock Award shall be granted to each such Non-Employee Director.

(ii)    To construe and interpret the Plan and Stock Awards granted under it,
and to establish, amend and revoke rules and regulations for its administration.
The Board, in the exercise of this power, may correct any defect, omission or
inconsistency in the Plan or in any Stock Award Agreement, in a manner and to
the extent it shall deem necessary or expedient to make the Plan fully
effective.

(iii)    To amend the Plan or a Stock Award as provided in Section 12.

(iv)    Generally, to exercise such powers and to perform such acts as the Board
deems necessary or expedient to promote the best interests of the Company that
are not in conflict with the provisions of the Plan.

(c)    EFFECT OF BOARD’S DECISION. All determinations, interpretations and
constructions made by the Board in good faith shall not be subject to review by
any person and shall be final, binding and conclusive on all persons.

4.    SHARES SUBJECT TO THE PLAN.

(a)    SHARE RESERVE. Subject to the provisions of Section 11 relating to
adjustments upon changes in the Common Stock, the Common Stock that may be
issued pursuant to Stock Awards shall not exceed in the aggregate six hundred
thousand (600,000) shares of Common Stock.

(b)    ANNUAL LIMIT ON STOCK AWARDS. No Participant shall be eligible to be
granted Stock Awards with an aggregate grant date fair value (computed in
accordance with the Company’s financial reporting policies) of more than
$500,000 during any calendar year, taken together with any cash fees paid to
such Participant in compensation for such Participant’s service on the Board
during such calendar year.

(c)    REVERSION OF SHARES TO THE SHARE RESERVE. If any Stock Award shall for
any reason expire or otherwise terminate, in whole or in part, without the
shares of Common Stock issuable thereunder being issued in full, the shares of
Common Stock not issued under such Stock Award shall revert to and again become
available for issuance under the Plan. For clarity, shares subject to a Stock
Award that are not delivered to a Participant because (i) such Participant’s
right to purchase such shares subject to an Option are surrendered in payment of
the exercise price for other shares subject to such Option in a “net exercise,”
or (ii) such shares are withheld in satisfaction of the withholding of taxes
incurred in connection with the exercise of an Option, or the issuance of shares
under a Restricted Stock Award or Restricted Stock Unit Award, the shares so
surrendered or withheld shall not remain available for subsequent issuance under
the Plan.

(d)    SOURCE OF SHARES. The shares of Common Stock subject to the Plan may be
unissued shares or reacquired shares, bought on the market or otherwise.

5.    ELIGIBILITY.

Stock Awards may be granted under the Plan to all Non-Employee Directors.

6.    OPTION PROVISIONS.

Each Option shall be in such form and shall contain such terms and conditions,
not inconsistent with the Plan, as the Board shall deem appropriate. The
provisions of separate Options need not be identical, but each Option shall
include (through incorporation of provisions hereof by reference in the Option
or otherwise) the substance of each of the following provisions:

(a)    TERM. No Option shall be exercisable after the expiration of ten (10)
years from the date it was granted.

(b)    EXERCISE PRICE. The exercise price of each Option shall be one hundred
percent (100%) of the Fair Market Value of the stock subject to the Option on
the date the Option is granted. Notwithstanding the foregoing, an Option may be
granted with an exercise price lower than that set forth in the preceding
sentence if such Option is granted pursuant to an assumption or substitution for
another option in a manner satisfying the provisions of Section 424(a) of the
Code.

(c)    CONSIDERATION. The purchase price of stock acquired pursuant to an Option
may be paid, to the extent permitted by applicable statutes and regulations, in
any combination of (i) cash or check, (ii) delivery to the Company of other
Common Stock, or (iii) surrender of Participant’s right to purchase shares
subject to such Option (valued, for such purposes, as the Fair Market Value of
such surrendered shares on the date of exercise less the exercise price for such
surrendered shares) in payment of the exercise price for other shares subject to
such Option in a “net exercise” of such Option.

(d)    TRANSFERABILITY. An Option is not transferable, except (i) by will or by
the laws of descent and distribution, (ii) by instrument to an inter vivos or
testamentary trust, in a form accepted by the Company, in which the Option is to
be passed to beneficiaries upon the death of the trustor (settlor) and (iii) by
gift, in a form accepted by the Company, to a member of the “immediate family”
of the Participant as that term is defined in 17 C.F.R. 240.16a-1(e). In
addition, the Participant may, by delivering written notice to the Company, in a
form satisfactory to the Company, designate a third party who, in the event of
the death of the Participant, shall thereafter be entitled to exercise the
Option.

(e)    VESTING. The total number of shares of Common Stock subject to an Option
may, but need not, vest and therefore become exercisable in periodic
installments that may, but need not, be equal. The Option may be subject to such
other terms and conditions on the time or times when it may be exercised (which
may be based on performance or other criteria) as the Board may deem
appropriate. The vesting provisions of individual Options may vary.

(f)    TERMINATION OF CONTINUOUS SERVICE. In the event an Participant’s
Continuous Service terminates (other than upon the Participant’s death or
Disability), the Participant may exercise his or her Option (to the extent that
the Participant was entitled to exercise it as of the date of termination) but
only within such period of time ending on the earlier of (i) the date six (6)
months following the termination of the Participant’s Continuous Service, or
(ii) the expiration of the term of the Option as set forth in the Stock Award
Agreement. If, after termination, the Participant does not exercise his or her
Option within the time specified in the Stock Award Agreement, the Option shall
terminate.

(g)    EXTENSION OF TERMINATION DATE. If the exercise of the Option following
the termination of the Participant’s Continuous Service (other than upon the
Participant’s death or Disability) would be prohibited at any time solely
because the issuance of shares would violate the registration requirements under
the Securities Act, then the Option shall terminate on the earlier of (i) the
expiration of the term of the Option set forth in Section 6(a) or (ii) the
expiration of a period of three (3) months after the termination of the
Participant’s Continuous Service during which the exercise of the Option would
not be in violation of such registration requirements.

(h)    DISABILITY OF PARTICIPANT. In the event an Participant’s Continuous
Service terminates as a result of the Participant’s Disability, the Participant
may exercise his or her Option (to the extent that the Participant was entitled
to exercise it as of the date of termination), but only within such period of
time ending on the earlier of (i) the date twelve (12) months following such
termination or (ii) the expiration of the term of the Option as set forth in the
Stock Award Agreement. If, after termination, the Participant does not exercise
his or her Option within the time specified herein, the Option shall terminate.

(i)    DEATH OF PARTICIPANT. In the event (i) an Participant’s Continuous
Service terminates as a result of the Participant’s death or (ii) the
Participant dies within the three-month period after the termination of the
Participant’s Continuous Service for a reason other than death, then the Option
may be exercised (to the extent the Participant was entitled to exercise the
Option as of the date of death) by the Participant’s estate, by a person who
acquired the right to exercise the Option by bequest or inheritance or by a
person designated to exercise the Option upon the Participant’s death, but only
within the period ending on the earlier of (A) the date eighteen (18) months
following the date of death or (B) the expiration of the term of such Option as
set forth in the Stock Award Agreement. If, after death, the Option is not
exercised within the time specified herein, the Option shall terminate.

7.    PROVISIONS OF STOCK AWARDS OTHER THAN OPTIONS.

(a)    RESTRICTED STOCK AWARDS. Each Restricted Stock Award shall be in such
form and shall contain such terms and conditions, not inconsistent with the
Plan, as the Board shall deem appropriate. The provisions of separate Restricted
Stock Awards need not be identical, but each Restricted Stock Award shall
include (through incorporation of provisions hereof by reference in the
Restricted Stock Award or otherwise) the substance of each of the following
provisions:

(i)    CONSIDERATION. Except as otherwise determined by the Board, no further
consideration will be payable by the Participant upon grant of the Restricted
Stock Award or delivery of each share of Common Stock subject to the Restricted
Stock Award. Any such consideration to be paid by the Participant may be paid in
any form of legal consideration that may be acceptable to the Board in its sole
discretion and permissible under applicable law.

(ii)    VESTING. At the time of the grant of a Restricted Stock Award, the Board
may, but need not, determine that Shares of Common Stock acquired under a
Restricted Stock Award shall be subject to a share repurchase option in favor of
the Company in accordance with a vesting schedule to be determined by the Board
in its sole discretion.

(iii)    TERMINATION OF PARTICIPANT’S CONTINUOUS SERVICE. In the event a
Participant’s Continuous Service terminates, the Company may repurchase or
otherwise reacquire any or all of the shares of Common Stock held by the
Participant which have not vested as of the date of termination under the terms
of the Restricted Stock Award.

(iv)    TRANSFERABILITY. Rights under the Restricted Stock Award shall be
transferable by the Participant only upon such terms and conditions as the Board
shall determine in its sole discretion.

(b)    RESTRICTED STOCK UNIT AWARDS. Each Restricted Stock Unit Award shall be
in such form and shall contain such terms and conditions as the Board shall deem
appropriate. The provisions of separate Restricted Stock Unit Awards need not be
identical, but each Restricted Stock Unit Award shall include (through
incorporation of provisions hereof by reference in the Restricted Stock Unit
Award or otherwise) the substance of each of the following provisions:

(i)    CONSIDERATION. Except as otherwise determined by the Board, no further
consideration will be payable by the Participant upon grant of the Restricted
Stock Unit Award or delivery of each share of Common Stock subject to the
Restricted Stock Unit Award. Any such consideration to be paid by the
Participant may be paid in any form of legal consideration that may be
acceptable to the Board in its sole discretion and permissible under applicable
law.

(ii)    VESTING. At the time of the grant of a Restricted Stock Unit Award, the
Board may, but need not, impose such restrictions or conditions to the vesting
of the Restricted Stock Unit Award as determined by the Board in its sole
discretion.

(iii)    PAYMENT. A Restricted Stock Unit Award may be settled by the delivery
of shares of Common Stock, their cash equivalent, any combination thereof or in
any other form of consideration, as determined by the Board in its sole
discretion.

(iv)    DIVIDEND EQUIVALENTS. Except as otherwise determined by the Board,
dividend equivalents shall not be credited in respect of shares of Common Stock
subject to a Restricted Stock Unit Award. If any such dividend equivalents are
so credited, such dividend equivalents may be converted into additional shares
of Common Stock subject to the Restricted Stock Unit Award in such manner as
determined by the Board in its sole discretion. Any additional shares of Common
Stock subject to the Restricted Stock Unit Award credited by reason of such
dividend equivalents will be subject to all the terms and conditions of the
underlying Restricted Stock Unit Award to which they relate.

(v)    TERMINATION OF PARTICIPANT’S CONTINUOUS SERVICE. Except as otherwise
determined by the Board, such portion of the Restricted Stock Unit Award that
has not vested will be forfeited upon the Participant’s termination of
Continuous Service.

(vi)    TRANSFERABILITY. Rights under the Restricted Stock Unit Award shall be
transferable by the Participant only upon such terms and conditions as the Board
shall determine in its sole discretion.

8.    COVENANTS OF THE COMPANY.

(a)    AVAILABILITY OF SHARES. During the terms of the Stock Awards, the Company
shall keep available at all times the number of shares of Common Stock required
to satisfy such Stock Awards.

(b)    SECURITIES LAW COMPLIANCE. The Company shall seek to obtain from each
regulatory commission or agency having jurisdiction over the Plan such authority
as may be required to grant Stock Awards and to issue and sell shares of Common
Stock upon exercise, grant or vesting of the Stock Awards; provided, however,
that this undertaking shall not require the Company to register under the
Securities Act the Plan, any Stock Award or any stock issued or issuable
pursuant to any such Stock Award. If, after reasonable efforts, the Company is
unable to obtain from any such regulatory commission or agency the authority
which counsel for the Company deems necessary for the lawful issuance and sale
of Common Stock under the Plan, the Company shall be relieved from any liability
for failure to issue and sell Common Stock upon exercise or grant of such Stock
Awards unless and until such authority is obtained.

9.    USE OF PROCEEDS FROM STOCK.

Proceeds from the sale of Common Stock pursuant to any Stock Award shall
constitute general funds of the Company.

10.     MISCELLANEOUS.

(a)    STOCKHOLDER RIGHTS. No Participant shall be deemed to be the holder of,
or to have any of the rights of a holder with respect to, any shares subject to
such Stock Award unless and until such Participant has satisfied all
requirements for the acquisition of shares of Common Stock underlying the Stock
Award pursuant to its terms.

(b)    NO SERVICE RIGHTS. Nothing in the Plan or any instrument executed or
Stock Award granted pursuant thereto shall confer upon any Participant any right
to continue to serve the Company as a Non-Employee Director or shall affect the
right of the Company or an Affiliate to terminate (i) the employment of an
Employee with or without notice and with or without cause, (ii) the service of a
Consultant pursuant to the terms of such Consultant’s agreement with the Company
or an Affiliate or (iii) the service of a Director pursuant to the Bylaws of the
Company or an Affiliate, and any applicable provisions of the corporate law of
the state in which the Company or the Affiliate is incorporated, as the case may
be.

(c)    INVESTMENT ASSURANCES. The Company may require a Participant, as a
condition of exercising or acquiring Common Stock under any Stock Award, (i) to
give written assurances satisfactory to the Company as to the Participant’s
knowledge and experience in financial and business matters and/or to employ a
purchaser representative reasonably satisfactory to the Company who is
knowledgeable and experienced in financial and business matters and that he or
she is capable of evaluating, alone or together with the purchaser
representative, the merits and risks of the Stock Award; and (ii) to give
written assurances satisfactory to the Company stating that the Participant is
acquiring the Common Stock subject to the Stock Award for the Participant’s own
account and not with any present intention of selling or otherwise distributing
the Common Stock. The foregoing requirements, and any assurances given pursuant
to such requirements, shall be inoperative if (iii) the issuance of the shares
upon the exercise or acquisition of Common Stock under the Stock Award has been
registered under a then currently effective registration statement under the
Securities Act or (iv) as to any particular requirement, a determination is made
by counsel for the Company that such requirement need not be met in the
circumstances under the then applicable securities laws. The Company may, upon
advice of counsel to the Company, place legends on stock certificates issued
under the Plan as such counsel deems necessary or appropriate in order to comply
with applicable securities laws, including, but not limited to, legends
restricting the transfer of the Common Stock.

(d)    WITHHOLDING OBLIGATIONS. The Participant may satisfy any federal, state
or local tax withholding obligation relating to the exercise or acquisition of
Common Stock under a Stock Award by any of the following means (in addition to
the Company’s right to withhold from any compensation paid to the Participant by
the Company) or by a combination of such means: (i) tendering a cash payment;
(ii) authorizing the Company to withhold shares from the shares of the Common
Stock otherwise issuable to the Participant as a result of the exercise or
acquisition of stock under the Stock Award; or (iii) delivering to the Company
owned and unencumbered shares of the Common Stock.

11.    ADJUSTMENTS UPON CHANGES IN STOCK.

(a)    CAPITALIZATION ADJUSTMENTS. If any change is made in the stock subject to
the Plan, or subject to any Stock Award, without the receipt of consideration by
the Company (through merger, consolidation, reorganization, recapitalization,
reincorporation, stock dividend, dividend in property other than cash, stock
split, liquidating dividend, combination of shares, exchange of shares, change
in corporate structure or other transaction not involving the receipt of
consideration by the Company), the Plan will be appropriately adjusted in the
class(es) and number of securities subject to the Plan pursuant to Section 4(a)
and the outstanding Stock Awards will be appropriately adjusted in the class(es)
and number of securities and price per share of stock subject to such
outstanding Stock Awards. The Board shall make such adjustments, and its
determination shall be final, binding and conclusive. For clarity, the
conversion of any convertible securities of the Company shall not be treated as
a transaction “without receipt of consideration” by the Company.

(b)    DISSOLUTION OR LIQUIDATION. In the event of a dissolution or liquidation
of the Company, then all outstanding Stock Awards shall terminate immediately
prior to such event.

(c)    ASSET SALE, MERGER, CONSOLIDATION OR REVERSE MERGER.

(i)    In the event of (i) a sale, lease or other disposition of all or
substantially all of the assets of the Company, (ii) a merger or consolidation
in which the Company is not the surviving corporation or (iii) a reverse merger
in which the Company is the surviving corporation but the shares of Common Stock
outstanding immediately preceding the merger are converted by virtue of the
merger into other property, whether in the form of securities, cash or
otherwise, then any surviving corporation or acquiring corporation shall assume
any Stock Awards outstanding under the Plan or shall substitute similar stock
awards (including an award to acquire the same consideration paid to the
stockholders in the transaction described in this subsection 11(c) for those
outstanding under the Plan).

(ii)    In the event any surviving corporation or acquiring corporation refuses
to assume such Stock Awards or to substitute similar stock awards for those
outstanding under the Plan, then the vesting of such Stock Awards shall be
accelerated in full, and the Stock Awards shall terminate if not exercised (if
applicable) at or prior to such event.

(iii)    In the event any surviving corporation or acquiring corporation assumes
such Stock Awards or substitutes similar stock awards for those outstanding
under the Plan but the Participant is not elected or appointed to the board of
directors of the surviving corporation or acquiring corporation at the first
meeting of such board of directors after such change in control event, then the
vesting of such Stock Awards shall be accelerated by eighteen (18) months on the
day after the first meeting of the board of directors of the surviving
corporation or acquiring corporation.

(iv)    In the event any surviving corporation or acquiring corporation assumes
such Stock Awards or substitutes similar stock awards for those outstanding
under the Plan and the Participant is elected or appointed to the board of
directors of the surviving corporation or acquiring corporation at the first
meeting of such board of directors after such change in control event, then the
vesting of such Stock Awards shall not be accelerated.

12.    AMENDMENT OF THE PLAN AND STOCK AWARDS.

(a)    AMENDMENT OF PLAN. The Board at any time, and from time to time, may
amend the Plan. However, except as provided in Section 11 relating to
adjustments upon changes in stock, no amendment shall be effective unless
approved by the stockholders of the Company to the extent stockholder approval
is necessary to satisfy the requirements of Rule 16b-3 or any Nasdaq or other
securities exchange listing requirements.

(b)    STOCKHOLDER APPROVAL. The Board may, in its sole discretion, submit any
other amendment to the Plan for stockholder approval.

(c)    NO IMPAIRMENT OF RIGHTS. Rights under any Option granted before amendment
of the Plan shall not be impaired by any amendment of the Plan unless (i) the
Company requests the consent of the Participant and (ii) the Participant
consents in writing.

(d)    AMENDMENT OF STOCK AWARDS. The Board at any time, and from time to time,
may amend the terms of any one or more Stock Awards; provided, however, that the
rights under any Stock Award shall not be impaired by any such amendment unless
(i) the Company requests the consent of the Participant and (ii) the Participant
consents in writing.

(e)    SUBSTITUTE AWARDS; NO REPRICING. Stock Awards may be granted in
substitution or exchange for any other Stock Award granted under the Plan or
under another plan of the Company or an Affiliate or any other right of an
eligible person to receive payment from the Company or an Affiliate. Stock
Awards may also be granted under the Plan in substitution for awards held by
individuals who become eligible persons as a result of a merger, consolidation
or acquisition of another entity or the assets of another entity by or with the
Company or an Affiliate (“Substitute Awards”). Such Substitute Awards referred
to in the immediately preceding sentence that are Options may have an exercise
price that is less than the Fair Market Value of a share of Common Stock on the
date of the substitution if such substitution complies with applicable laws
(including rules regarding nonqualified deferred compensation) and exchange
rules. Except as provided in this Section 12(e) or in Section 11, without the
approval of the stockholders of the Company, the terms of outstanding Stock
Awards may not be amended to (i) reduce the exercise price of an outstanding
Option, (ii) grant a new Option or other Stock Award in substitution for, or
upon the cancellation of, any previously granted Option that has the effect of
reducing the exercise price thereof, (iii) exchange any Option for Common Stock,
cash or other consideration when the exercise price or grant price per share of
Common Stock under such Option exceeds the Fair Market Value of a share of
Common Stock.

13.    TERMINATION OR SUSPENSION OF THE PLAN.

(a)    PLAN TERM. The Board may suspend or terminate the Plan at any time.
Unless sooner terminated, the Plan shall terminate on the day before the tenth
(10th) anniversary of the date the Plan is adopted by the Board or approved by
the stockholders of the Company, whichever is earlier. No Stock Awards may be
granted under the Plan while the Plan is suspended or after it is terminated.

(b)    NO IMPAIRMENT OF RIGHTS. Suspension or termination of the Plan shall not
impair rights and obligations under any Stock Award granted while the Plan is in
effect except with the written consent of the Participant.

14.    EFFECTIVE DATE OF PLAN.

The Plan shall become effective as determined by the Board, but no Option shall
be exercised and no Restricted Stock Award or Restricted Stock Unit Award shall
be granted unless and until the Plan has been approved by the stockholders of
the Company, which approval shall be within twelve (12) months before or after
the date the Plan is adopted by the Board.

15.    CHOICE OF LAW.

All questions concerning the construction, validity and interpretation of this
Plan shall be governed by the law of the State of Delaware, without regard to
such state’s conflict of laws rules.

AMENDMENT NO.1 TO
LEXICON PHARMACEUTICALS, INC.
2017 NON-EMPLOYEE DIRECTORS’ EQUITY INCENTIVE PLAN

This Amendment No. 1 to the 2017 Non-Employee Directors’ Equity Incentive Plan
(the “Plan”) was adopted by the Board of Directors of Lexicon Pharmaceuticals,
Inc. on October 25, 2018 pursuant to Section 12(a) of the Plan.

Section 6(c) of the Plan is hereby amended and restated to read in its entirety
as follows:

“(c)    CONSIDERATION. The purchase price of stock acquired pursuant to an
Option may be paid, to the extent permitted by applicable statutes and
regulations, in any combination of (i) cash or check, (ii) delivery to the
Company of other Common Stock, or (iii) surrender of Participant’s right to
purchase shares subject to any Option with a term expiring in less than one (1)
year from the date of exercise (valued, for such purposes, as the Fair Market
Value of such surrendered shares on the date of exercise less the exercise price
for such surrendered shares) in payment of the exercise price for other shares
subject to such Option in a “net exercise” of such Option.”

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