Exhibit 10.1

AERPIO THERAPEUTICS, INC.

2011 EQUITY INCENTIVE PLAN

ARTICLE I

ESTABLISHMENT AND TERM

Section 1.01 Establishment; Definitions. This Plan was adopted by the Board
effective December 22, 2011 (the “Effective Date”), and by the stockholders of
the Corporation effective December 22, 2011. All capitalized terms used herein
are defined herein or in Appendix A attached hereto.

Section 1.02 Term. The Board may suspend or terminate the Plan at any time.
Unless sooner terminated, the Plan shall terminate on the tenth anniversary of
the Effective Date. No Equity Awards may be granted under the Plan while the
Plan is suspended or after it is terminated. Suspension or termination of the
Plan shall not impair rights and obligations under any Equity Award granted
while the Plan is in effect, except with the consent of the person to whom the
Equity Award was granted.

ARTICLE II

STRUCTURE AND PURPOSE

Section 2.01 Structure of Plan. The Equity Awards issued under the Plan shall be
either, in the discretion of the Board, (a) Options granted pursuant to Article
VI hereof, including Incentive Stock Options and Non-statutory Stock Options, or
(b) Stock bonuses or restricted Stock awards granted pursuant to Article VII
hereof. All Options shall be designated as Incentive Stock Options or
Non-statutory Stock Options at the time of grant.

Section 2.02 Purpose. The purpose of the Plan is to promote the interests of the
Corporation by aligning the interests of selected eligible persons under the
Plan with the interests of the stockholders of the Corporation and by providing
to such persons an opportunity to obtain the benefits from ownership of the
Corporation’s Stock through the granting to such persons of Equity Awards. The
Corporation, through the use of the Plan, seeks to attract and retain the
services of Employees, Directors and Consultants, and to provide additional
incentives for such persons apart from the provisions of their employment
agreements or other arrangements with the Corporation or its Affiliates.

ARTICLE III

ADMINISTRATION

Section 3.01 Board; Delegation to Committee. The Board shall administer the Plan
unless and until the Board delegates administration to a Committee. The Board
may delegate administration of the Plan to a Committee composed of two or more
members of the Board, composed solely of Outside Directors or composed, if
applicable law permits, of one or more officers of the Corporation. If
administration is delegated to a Committee, the Committee shall have, in
administering the Plan, all of the powers that were possessed by the Board prior
to such delegation, subject, however, to such resolutions, not inconsistent with
the provisions of the Plan, as may be adopted from time to time by the Board. If
administration is delegated to a Committee, all references in this Plan to the
Board shall thereafter be to the Committee. The Board may abolish the Committee
at any time and revest in the Board the administration of the Plan.

Section 3.02 Administration. The Board shall have the power, consistent with the
express provisions of the Plan:

(a) To determine from time to time which of the eligible persons under the Plan
shall be granted Equity Awards;

(b) To determine whether an Equity Award shall be an Incentive Stock Option, a
Non-statutory Stock Option, a Stock bonus, a restricted Stock award or a
combination of the foregoing;

(c) To approve forms of Equity Award Agreements for use under the Plan;

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(d) To determine the number of shares of Stock to be covered by each Equity
Award granted hereunder;

(e) To determine how and when each Equity Award shall be granted, the provisions
of each Equity Award granted (including, but not limited to, provisions setting
forth or relating to exercise price, vesting schedule, vesting acceleration,
forfeiture and rights of repurchase), and to provide for any and all other terms
and conditions in an Equity Award which are not expressly prohibited by the
Plan;

(f) To construe and interpret the Plan and Equity Awards granted under it, and
to establish, amend and revoke rules and regulations for the administration of
such Plan and Equity Awards;

(g) To correct any defect, omission or inconsistency in the Plan or in any
Equity Award Agreement, in a manner and to the extent it shall deem necessary or
expedient to make the Plan fully effective;

(h) To amend the Plan or an Equity Award as provided in Article XI; and

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

Any determination by the Board with respect to the matters referred to above
shall be final and conclusive.

ARTICLE IV

ELIGIBILITY

Section 4.01 Persons Eligible for Equity Awards. Incentive Stock Options may be
granted only to Employees who meet the definition of “employee” under
Section 3401 (c) of the Code on the date of grant. Equity Awards other than
Incentive Stock Options may be granted only to Employees, Directors or
Consultants. The extent to which any such person shall be entitled to be granted
Equity Awards pursuant to the Plan shall be determined in the sole and absolute
discretion of the Board. Eligibility to participate does not confer upon any
Employee any right to be granted Equity Awards and the acceptance of any Equity
Award by an Employee is voluntary.

Section 4.02 Other Limitations. If any payment or right accruing to an
individual under this Plan (without the application of this Section 4.02),
either alone or together with other payments or rights accruing to such
individual from the Corporation or an Affiliate of the Corporation (“TOTAL
PAYMENTS”), would constitute a “parachute payment” (as defined in Section 280G
of the Code), such payment or right shall be reduced to the largest amount or
greatest right that will result in no portion of the amount payable or right
accruing under this Plan being subject to an excise tax under Section 4999 of
the Code or being disallowed as a deduction under Section 280G of the Code,
provided that the foregoing shall not apply to the extent provided otherwise in
an Equity Award Agreement or in the event the affected individual is party to an
agreement with the Corporation or an Affiliate of the Corporation that
explicitly provides for an alternate treatment of payments or rights that would
constitute “parachute payments.” If the Total Payments are subject to reduction
under this Section 4.02, the Corporation shall reduce the Total Payments by
first reducing or eliminating any cash payments to which the individual may be
entitled (with the payments to be made furthest in the future being reduced
first), then by reducing or eliminating any accelerated vesting of any Option or
Stock under the Plan. The determination of whether any reduction in the rights
or payments under this Plan is to apply shall be made by the Board in good faith
after consultation with the affected individual, and such determination shall be
conclusive and binding on such affected individual. The affected individual
shall cooperate in good faith with the Board in making such determination and
providing the necessary information for this purpose. The foregoing provisions
of this Section 4.02 shall apply with respect to any person only if, after
reduction for any applicable Federal excise tax imposed by Section 4999 of the
Code and Federal income tax imposed by the Code, the Total Payments accruing to
such person would be less than the amount of the Total Payments as reduced, if
applicable, under the foregoing provisions of this Section 4.02 and after
reduction for any applicable Federal income tax imposed by the Code. At the
request of an affected individual, the Corporation shall use its reasonable best
efforts to obtain approvals as may be required, including stockholder approvals,
to cause payments made under this Plan to be exempt from the definition of
‘‘parachute payments” under

 

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Section 280G of the Code, if such payments hereunder are made in connection with
the events described under Section 280G of the Code. Notwithstanding any
provision contained herein to the contrary, the Corporation shall not be
responsible for the payment of any excise taxes incurred by any person under
Section 4999 of the Code or for any tax gross-up payments at any time,
including, but not limited to, in the event that the appropriate approvals are
not obtained or in the event that exemptions to “parachute payments” no longer
apply.

ARTICLE V

SHARES SUBJECT TO THE PLAN

Section 5.01 Authorized Shares. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, no more than [ ] shares of Stock
may be issued pursuant to Equity Awards. All of the shares of Stock may be
issued in the form of Incentive Stock Options. The number of shares of Stock
reserved for issuance under this Plan may be increased from time to time as
permitted by law.

Section 5.02 Calculation of Stock Available Under Plan. If any Equity Award
shall for any reason expire, be cancelled, be forfeited or otherwise terminate,
in whole or in part, without having been exercised in full, or if shares of
Stock are not delivered because an Equity Award is settled in cash or because
such shares of Stock are used to satisfy the exercise price, an applicable tax
withholding obligation, in whole or in part, or if shares of Stock which
originally underlay an Equity Award are repurchased or otherwise reacquired by
the Corporation, the Stock not acquired or delivered or reacquired (as the case
may be) under such Equity Award by the holder thereof shall revert to and again
become available for issuance under the Plan. The Stock subject to the Plan may
be unissued shares or reacquired shares, bought on the market or otherwise.

Section 5.03 Annual Limitations. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, the maximum number of shares of
Stock that may be issued pursuant to Equity Awards in any consecutive twelve
month period during the Term shall not exceed the limits imposed by Rule 701
under the Securities Act of 1933 and no holder shall be granted Equity Awards
that in the aggregate exceed [    ] shares of Stock in any calendar year during
the Term.

ARTICLE VI

TERMS OF OPTIONS

Section 6.01 Form of Option. Subject to the provisions of the Plan, each Option
shall be in such form and shall contain such terms and conditions as the Board
shall determine. The provisions of separate Options need not be identical.

Section 6.02 Term. No Option shall be exercisable after the expiration often
(10) years from the date it was granted.

Section 6.03 Date of Grant. For purposes of determining the exercise price under
Section 6.04, except as may be otherwise provided in an Equity Award, the grant
date of an Option granted under this Plan shall be the date as of which the
Committee approves the Option if the Option is a unilateral grant and shall be
the date on which the later of the Optionee and an authorized officer of the
Corporation executes the Option if the Option is a bilateral grant.

Section 6.04 Exercise Price. The exercise price of each Incentive Stock Option
shall be not less than one hundred percent (100%) of the Fair Market Value of
the Stock subject to the Option on the date the Option is granted. The exercise
price of each Non-statutory Stock Option shall be the exercise price determined
by the Board. Notwithstanding the foregoing, an Option (whether an Incentive
Stock Option or a Non-statutory Stock Option) may be granted with an exercise
price lower than that otherwise provided in this Section 6.03 if such Option is
granted pursuant to an assumption or substitution for another option in a manner
satisfying the provisions of Section 424(a) and Section 409A of the Code.

 

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Section 6.05 Exercise of Options. Subject to the provisions of Section 6.07, an
Optionee may at any time prior to the expiration or termination of an Option
elect to purchase all or a portion of the Stock subject to such Option which
such holder is then entitled to purchase by delivering to the Corporation a
completed Stock Purchase Agreement specifying the number of shares of Stock the
Participant desires to purchase. An Option may be exercised for whole shares of
Stock only. The Stock Purchase Agreement shall be accompanied by payment of the
applicable exercise price for Stock being acquired. Subject to the provisions of
the Equity Award Agreement, the Corporation shall cause to be delivered to the
holder a certificate for the shares of Stock so purchased. If the number of
shares so purchased is less than the number of shares of Stock subject to the
Option, the Corporation shall deliver to the holder a memorandum of the number
of shares in respect of which the Option has been exercised and the number of
shares which remain subject to the Option.

Section 6.06 Payment. The entire purchase price of Stock acquired pursuant to an
Option shall be payable in full by, as applicable, cash or check for an amount
equal to the aggregate purchase price for the number of shares being purchased,
or in the discretion of the Administrator, upon any of the following terms:
(i) by a copy of instructions to a broker directing such broker to sell the
number of shares of Stock for which an Option is exercised, and to remit to the
Corporation the aggregate purchase price of such shares; (ii) by paying all or a
portion of the purchase price by tendering shares of Stock owned by the
Optionee, duly endorsed for transfer to the Corporation, with a Fair Market
Value on the date of delivery equal to the aggregate purchase price with respect
to the number of shares of Stock for which an Option is exercised; (iii) by a
share-for-share exercise by means of attestation whereby the Optionee identifies
for delivery specific shares of Stock already owned by the Optionee and receives
a number of shares of Stock equal to the difference between the Option thereby
exercised and the identified attestation shares of Stock; or (iv) by directing
the Corporation in writing to deliver to the Optionee a number of shares equal
to the number of shares for which the Option is exercised less a number of
shares with a Fair Market Value on the date of exercise equal to the aggregate
purchase price of the shares for which the Option is exercised.

Section 6.07 Transferability. An Incentive Stock Option and, unless otherwise
provided in an Equity Award Agreement, a Non-statutory Stock Option shall not be
transferable except by will or by the laws of descent and distribution, and
shall be exercisable during the lifetime of the person to whom the Option is
granted only by such person.

Section 6.08 Vesting. Subject to the provisions of the Plan, the Board, in its
discretion, shall determine at the time of grant the time when an Option vests,
becomes exercisable and shall expire, and such determinations shall be set forth
in the applicable Equity Award Agreement. An 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, and
the Board may provide for early exercise ofunvested Options (with the Stock
received therefor being itself subject to vesting) if expressly set forth in an
Equity Award Agreement. Unless otherwise approved by the Board and set forth in
writing by an authorized officer of the Corporation, an Option shall cease
vesting upon the Optionee’s Termination, regardless of whether or not the
Optionee was given requisite notice of Termination of such Optionee’s employment
by the Corporation or by any Affiliate of the Corporation.

Section 6.09 Termination of Employment or Relationship as a Director or
Consultant. An Option will expire immediately upon the Optionee’s Termination
for Cause. Unless otherwise provided in the Equity Award Agreement relating to
an Option, in the event of an Optionee’s Termination for reasons other than
Cause, the Optionee’s death or the Optionee’s Disability, the Optionee may
exercise the Option to the extent of the shares in respect of which such Option
is exercisable on the date notice of Termination is given to the Optionee by the
Corporation or any Affiliate of the Corporation at any time beginning on such
date and ending on the earlier of (a) the date thirty (30) days after such
notice of Termination is delivered to the Optionee, or (b) the expiration of the
term of the Option as set forth in the Equity Award Agreement. The time period
for the exercise of such Options applies regardless of the sufficiency or the
length of notice of Termination given by the Corporation or any Affiliate of the
Corporation to the Optionee.

Section 6.10 Disability of Optionee. Unless otherwise provided in the Equity
Award Agreement relating to an Option, in the event of a Termination as a result
of the Optionee’s Disability, the Optionee may exercise the Option to the extent
of the shares of Stock in respect of which such Option is exercisable on the
date notice of Termination is given to the Optionee by the Corporation or any
Affiliate of the Corporation at any time beginning on such date and ending on
the earlier of (a) the one year anniversary of the date such notice of
Termination is delivered to the Optionee, or (b) the expiration of the term of
the Option as set forth in the Equity Award Agreement.

 

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Section 6.11 Death of Optionee. Unless otherwise provided in the Equity Award
Agreement relating to an Option, in the event of a Termination as a result of
the Optionee’s death, the Optionee’s estate or a person who acquired the right
to exercise the Option by bequest or inheritance may exercise the Option to the
extent of the Shares in respect of which such Option is exercisable on the date
of death at any time beginning on such date and ending on the earlier of (a) the
first anniversary of the date of death, or (b) the expiration of the term of the
Option as set forth in the Equity Award Agreement.

Section 6.12 Incentive Stock Option Limitations. The following limitations shall
apply to a grant of an Incentive Stock Option:

(a) If, at the time of the grant of an Incentive Stock Option, the Optionee owns
(or is deemed to own pursuant to Section 424(d) of the Code) equity securities
possessing more than ten percent (10%) of the total combined voting power of all
classes of equity securities of the Corporation or of any of its Affiliates, the
exercise price of such Incentive Stock Option shall be at least one hundred and
ten percent (110%) of the Fair Market Value of such Stock on the date of grant
and the Incentive Stock Option shall terminate on the date that is within five
(5) years after the date of grant.

(b) If the aggregate Fair Market Value (determined as of the time the Incentive
Stock Option with respect to such Stock is granted) of Stock with respect to
which Incentive Stock Options are exercisable for the first time by the Optionee
during any calendar year (under all plans of the Corporation and its Affiliates)
exceeds one hundred thousand dollars ($100,000), the Options or portions thereof
that exceed such limit shall be treated as Non-statutory Stock Options.

Section 6.13 Cancellation and Regrant. The Board shall have the authority to
effect, at any time and from time to time, (a) the repricing of any outstanding
Options under the Plan, or (b) with the consent of the affected holders of
Options, the cancellation of any outstanding Options under the Plan and the
grant in substitution therefor of new Options under the Plan covering the same
or different numbers of shares of Stock and having an exercise price per share
as determined by the Board.

Section 6.14 Qualification of Incentive Stock Options. Anything in the Plan to
the contrary notwithstanding, no term of the Plan relating to Incentive Stock
Options shall be interpreted, amended or altered, nor shall any discretion or
authority granted under the Plan be exercised, so as to disqualify the Plan
under Section 422 of the Code or, without the written consent of the Optionee
affected, to disqualify any Incentive Stock Option under Section 422 of the
Code.

ARTICLE VII

TERMS OF STOCK BONUSES AND RESTRICTED STOCK AWARDS

Section 7.01 Form of Stock Bonus or Restricted Stock Award. Subject to the
provisions of the Plan, each Stock bonus or restricted Stock award shall be in
such form and shall contain such terms and conditions as the Board shall
determine. The provisions of separate Stock bonuses or restricted Stock awards
need not be identical.

Section 7.02 Date of Grant. Except as may be otherwise provided in an Equity
Award, the grant date of a Stock Bonus or Restricted Stock Award granted under
this Plan shall be the date as of which the Committee approves the award if the
Stock Bonus or Restricted Stock Award is a unilateral grant and shall be the
date on which the later of the holder and an authorized officer of the
Corporation executes the award if the Stock Bonus or Restricted Stock Award is a
bilateral grant.

Section 7.03 Purchase Price. The purchase price, if any, for any Stock granted
as a Stock bonus or restricted Stock award shall be such amount as the Board
shall determine and designate in the Equity Award Agreement. Notwithstanding the
foregoing, the Board may determine that eligible participants in the Plan may be
awarded Stock in consideration for past services rendered to the Corporation or
an Affiliate thereof or for the benefit of the Corporation or an Affiliate
thereof. Upon the award of any Stock bonus or restricted Stock award and the
payment of any purchase price, if applicable, the holder of such Stock bonus or
restricted Stock award shall deliver to the Corporation a completed Stock
Purchase Agreement.

 

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Section 7.04 Transferability. Unless otherwise provided in the Equity Award
Agreement and subject to the provisions of any applicable buy-sell or similar
agreements, Stock awarded or purchased pursuant to this Article VII shall not be
transferable except by will or by the laws of descent and distribution, or
except in connection with a Corporate Transaction, until such time as any
vesting restrictions and/or repurchase rights thereon shall lapse.

Section 7.05 Payment. Unless otherwise provided in the applicable Equity Award
Agreement, the purchase price, if any, of Stock acquired pursuant to a Stock
bonus or restricted Stock award shall be paid in cash (by check) or, in the
discretion of the Board, by promissory note (with terms determined by it in its
discretion) prior to the issuance of any Stock pursuant to such award.

Section 7.06 Vesting. Subject to the provisions of the Plan, the Board, in its
discretion, shall determine whether shares of Stock sold or awarded under
Article VII of the Plan shall be subject to vesting or to repurchase by the
Corporation, and the time or times when such vesting restrictions and/or
repurchase rights shall lapse, and such determinations shall be set forth in the
applicable Equity Award Agreement. An Equity Award may be subject to such other
terms and conditions on the time or times when it may vest (which may be based
on performance or other criteria) as the Board may deem appropriate if expressly
set forth in an Equity Award Agreement. Unless otherwise approved by the Board
and set forth in writing by an authorized officer of the Corporation, a Stock
bonus or restricted Stock award shall cease vesting upon the holder’s
Termination, and (if applicable) the right to acquire any Stock purchasable
thereunder which has not been purchased by such time shall terminate, regardless
of whether or not the holder was given requisite notice of Termination of such
holder’s employment by the Corporation or by any Affiliate of the Corporation.

ARTICLE VIII

ADJUSTMENTS UPON CHANGES IN STOCK; CORPORATE TRANSACTIONS

Section 8.01 Change in Stock. If any change is made in the Stock subject to the
Plan, through a 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 Corporation (other than a Corporate Transaction), the Plan
will be appropriately adjusted in the class(es) and maximum number of shares
subject to the Plan pursuant to Article V, and the outstanding Equity Awards
will be appropriately adjusted (to the extent not previously exercised by the
holders thereof) in the class(es) and number of shares subject thereto and in
the exercise price of such outstanding Equity Awards. If as a result of such
event, a holder of an Equity Award would become entitled to a fractional share
of Stock or other security, such holder shall have the right to purchase only
the next lowest whole number of shares of Stock or other security and no payment
or other adjustment will be made with respect to the fractional interest so
disregarded. The Board shall make such adjustments at the time of the change in
the Stock, whether or not specifically provided for in any outstanding Equity
Award. The Board’s determination shall be final, binding and conclusive.
Notwithstanding the foregoing, any such adjustment shall be made only if and to
the extent that such adjustment would not cause any Equity Award intended to
qualify as an Incentive Stock Option to fail to so qualify.

Section 8.02 Corporate Transaction. Unless the surviving corporation (or a
parent or subsidiary of such corporation) in the Corporate Transaction assumes
this Plan or such Equity Award or issues a substitute therefor or unless the
Board provides in substitution for any outstanding Equity Award such alternative
consideration as it, in good faith, may determine to be equitable in the
circumstances, including cash, or unless otherwise provided in the Equity Award
Agreement pursuant to which such Equity Award was originally granted, and
subject to the provisions of Section 10.01, the following shall apply in the
event of a Corporate Transaction:

(a) If such Equity Award is an Option, then it shall terminate upon the
effective date of the Corporate Transaction to the extent not exercised prior
thereto.

(b) If such Equity Award is a Stock bonus or restricted Stock award, then
(i) the vested portion thereof shall survive the Corporate Transaction and shall
be subject to the terms and conditions of such Corporate Transaction (including,
but not limited to, any terms and conditions applicable to the sale, exchange,
conversion or other disposition of such Stock bonus or Restricted Stock award in
such Corporation Transaction), and (ii) the unvested portion thereof shall
terminate upon the effective date of the Corporate Transaction (provided that in
connection with the consummation of such Corporate Transaction, the Corporation
shall pay the holder thereof an amount equal to the purchase price (if any)
originally paid by such holder for the Stock bonus or Restricted Stock award so
terminated).

 

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(c) No Equity Award may be made after the effective date of the Corporate
Transaction.

ARTICLE IX

COVENANTS OF THE CORPORATION

Section 9.01 Reservation of Stock. The Corporation shall reserve from its
authorized but unissued Stock the number of shares of Stock issuable pursuant to
outstanding Equity Awards.

Section 9.02 Regulatory Authority. The Corporation shall seek to obtain from
each regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to make an Equity Award and to issue and sell
shares of Stock upon the exercise of outstanding Equity Awards, provided that
this undertaking shall not require the Corporation to register under the
Securities Act or under any applicable state securities laws either the Plan,
any Equity Award or any Stock issued or issuable pursuant to any such Equity
Award. If, after reasonable efforts, the Corporation is unable to obtain from
any such regulatory commission or agency the authority for the lawful grant of
any such Equity Award or the lawful issuance and sale of Stock under the Plan,
then, as the case may be, the Equity Award so granted shall be nullified or the
Corporation shall be relieved from any liability for failure to issue and sell
Stock upon exercise of such Equity Awards unless and until such authority is
obtained.

ARTICLE X

GENERAL PROVISIONS

Section 10.01 Acceleration of Vesting. Notwithstanding any provision in any
Equity Award Agreement, the Board may, in its discretion, accelerate the time at
which an Equity Award may first be exercised or the time during which an Equity
Award or any part thereof will vest.

Section 10.02 Stockholder Rights. Except as set forth in the Equity Award
Agreement, no holder of any Equity Award shall be deemed to be the holder of, or
to have any of the rights of a holder with respect to, any Stock subject to such
Equity Award unless and until such person has satisfied all requirements for
vesting or exercise of the Equity Award pursuant to its terms and the amount due
in payment for Stock to be issued pursuant to such Equity Award Agreement, if
any, has been paid in full to the Corporation.

Section 10.03 Employment or Other Services. Nothing in the Plan, any Equity
Award Agreement or any instrument executed pursuant thereto shall (a) confer
upon any Employee or other holder of an Equity Award any right to employment or
to continue in the employ of the Corporation or any Affiliate, (b) confer upon
any Director or Consultant or other holder of an Equity Award any right to act
or to continue acting as a Director or Consultant, (c) affect the right of the
Corporation or any Affiliate to terminate the employment of any Employee with or
without Cause, (d) affect the right of the Corporation’s Board and/or the
Corporation’s stockholders to remove any Director pursuant to the terms of the
Corporation’s charter documents and the provisions of applicable law, or
(e) affect the right of the Corporation to terminate the relationship of any
Consultant pursuant to the terms of such Consultant’s agreement with the
Corporation or Affiliate.

Section 10.04 Securities Requirements. The Corporation hereby informs each
recipient of an Equity Award that the Equity Award and the Stock subject thereto
(a) have not been qualified by prospectus and are subject to indefmite holding
periods, and (b) are unregistered securities under the Securities Act and under
all applicable state securities laws and must be held indefinitely unless they
are subsequently registered or qualified thereunder or an exemption from such
registration or qualification is available. The grant of any Equity Award and
the issuance of any shares of Stock by the Corporation pursuant to an Equity
Award is subject to compliance with the laws, rules and regulations of all
public agencies and authorities applicable to the issuance and distribution of
such Equity Award and/or Stock and to the listing requirements of any stock
exchange or exchanges on which the Stock may be listed from time to time. The
recipient agrees (a) to comply with all such laws, rules and regulations, (b) to
furnish to the Corporation any information, report and/or undertakings required
to comply with all such laws, rules and

 

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regulations, and (c) to fully cooperate with the Corporation in complying with
such laws, rules and regulations. The Corporation may require any person to whom
an Equity Award is granted, or any person to whom an Equity Award is
transferred, as a condition of exercising or acquiring Stock under any Equity
Award, to give written assurances satisfactory to the Corporation (a) as to the
matters provided above, (b) as to such person’s knowledge and experience in
financial and business matters, (c) that he or she is capable of evaluating,
alone or together with a purchaser representative, the merits and risks of
exercising the Equity Award, and (d) that such person is acquiring the Stock
subject to the Equity Award for such person’s own account and not with any view
to a distribution of the Stock. The Corporation may, upon advice of counsel to
the Corporation, 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 Stock. Notwithstanding anything to the contrary contained in this Plan or
an Equity Award Agreement, no Stock shall be issued to a person pursuant to an
Equity Award unless such shares of Stock are then registered under the
Securities Act and registered or qualified under all applicable state securities
laws, or if such shares are not then so registered or qualified, the Corporation
has determined that such issuance would be exempt from the registration
requirements of the Securities Act and all applicable state securities laws.

Section 10.05 Tax Withholding. Unless otherwise provided in the applicable
Equity Award Agreement or by the Board, the Corporation shall require the holder
of an Equity Award to pay in cash (by check) to the Corporation the holder’s
share of any tax withholding arising under any applicable law by reason of such
Equity Award, the vesting thereof or the disposition of Stock subject thereto.
Alternatively, if permitted by the Administrator in its sole discretion in
connection with the exercise of an Option or the vesting of a bonus Stock or
restricted Stock award only, the holder may direct the Corporation in writing to
withhold a number of shares having an aggregate Fair Market Value on the date of
exercise or vesting equal to the minimum amount required be withheld in
connection with the exercise of the Option or the vesting of the Stock by
applicable taxing authorities. Subject to its withholding obligations under
applicable law, and notwithstanding any other provision ofthis Plan, the
Corporation does not assume responsibility for the income or other tax
consequences for any person who is eligible for or has received an Equity Award
under the Plan, and such persons are advised to consult with their own tax
advisers with respect to such matters.

Section 10.06 Equity Award Agreement. The grant of any Equity Award is subject
to the execution by the recipient of an Equity Award Agreement.

ARTICLE XI

AMENDMENT OF THE PLAN AND EQUITY AWARDS

Section 11.01 Amendment and Termination of Plan; Stockholder Approval. The Board
may, in its discretion, amend or terminate the Plan, provided, however, that no
such action may adversely and materially affect the rights of a holder of an
Equity Award without the holder’s written consent. Such amendment or termination
shall be effective on the date the Board determines, except for amendments that
require the approval of the Corporation’s stockholders, in which case such
amendments shall be effective on the date the Corporation’s stockholders approve
the amendment. The Board may, in its discretion, submit any amendment or
termination of the Plan for stockholder approval.

Section 11.02 Changes in Law. The Board may amend the Plan as it deems necessary
or advisable to provide eligible Employees, Directors or Consultants with the
maximum benefits provided or to be provided under the provisions of the Plan
relating to Incentive Stock Options and to bring the Plan or Incentive Stock
Options granted under the Plan into compliance therewith. The Board may also, in
its discretion, amend the Plan to take into account changes in law and tax and
accounting rules, as well as other developments, and to grant Equity Awards that
qualify for beneficial treatment under such rules.

 

8

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APPENDIX A

DEFINITIONS

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

“BOARD” means the Board of Directors of the Corporation.

“CAUSE” has the meaning given it in the employment or consulting agreement which
governs the relationship between the Corporation and the holder of the Equity
Award or, if there is no such definition in any such agreement, means
(a) indictment or conviction for either any felony offense or any other crime
involving dishonesty, (b) participation in any fraud, theft, embezzlement or
other misconduct against the Corporation, (c) intentional damage to any property
of the Corporation, (d) breach of the holder’s duties of good faith and fair
dealing that are owed to the Corporation, (e) breach or violation of any
employment, confidentiality, non-competition, non-solicitation or assignment of
inventions agreement, (f) conduct which in the good faith and reasonable
determination of the Board demonstrates gross unfitness to serve, (g) failure to
comply with the policies of the Corporation that have been approved by the
Board, or (h) insubordination or failure to follow the directions of the Board
or of the Chief Executive Officer or President of the Corporation.

“CODE” means the Internal Revenue Code of 1986, as amended, and the regulations
promulgated thereunder.

“COMMITTEE” means a Committee appointed by the Board in accordance with
Section 3.01 of the Plan.

“CORPORATION” means Aerpio Therapeutics, Inc., a Delaware corporation, and its
successors and assigns.

“CONSULTANT” means any person, including an advisor, engaged by the Corporation
or an Affiliate to render bona fide consulting services (other than services in
connection with the offer or sale of securities in a capital-raising
transaction) and who is compensated for such services, provided that the term
“Consultant” shall not include Directors who are paid only a director’s fee by
the Corporation or who are not compensated by the Corporation for their services
as Directors.

“CORPORATE TRANSACTION” means a “Deemed Liquidation Event” as such term is
defined in the Corporation’s charter documentation, as in effect from time to
time.

“DIRECTOR” means a member of the Board.

“DISABILITY” has the meaning given it in the employment or consulting agreement
which governs the relationship between the Corporation and the holder of the
Equity Award or, if there is no such defmition in any such agreement, means any
medically determinable physical or mental impairment rendering an individual
unable to engage in any substantial gainful activity, which disability can be
expected to result in death or which has lasted or can be expected to last for a
continuous period of not less than six (6) months.

“EMPLOYEE” means any person employed, whether full or part-time, as an employee
(including as an officer) by the Corporation or any Affiliate of the
Corporation. Neither service as a Director nor payment of a director’s fee by
the Corporation shall be sufficient to constitute “employment” by the
Corporation. However, a Director who is also employed as an employee by the
Corporation or an Affiliate shall constitute an Employee hereunder.

“EQUITY AWARD” means any right granted under the Plan, including any Option, any
Stock bonus or any right to purchase restricted Stock.

 

9

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“EQUITY A WARD AGREEMENT” means a written agreement between the Corporation and
a holder of an Equity Award evidencing the terms and conditions of an individual
Equity Award grant. Each Equity Award Agreement shall be subject to the terms
and conditions of the Plan.

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

 

  •   If the Stock is listed on any established stock exchange or a national
market system, including, but not limited to, the Nasdaq National Market or
Nasdaq Small Cap Market, the Fair Market Value of a share of Stock shall be the
last sales price for the Stock (or the closing bid, if no sales were reported)
as quoted on such system or exchange, as reported in The Wall Street Journal or
such other source as the Board deems reliable.

 

  •   In the absence of an established market for the Stock, the Fair Market
Value shall be determined in good faith by the Board, shall take into account
appropriate discounts for lack of marketability or due to a minority position,
and shall take into account the applicable preferences and privileges of the
Corporation’s preferred stock as set forth in the Corporation’s .charter
documentation, as in effect from time to time.

“INCENTIVE STOCK OPTION” means an Option intended to qualify as an incentive
stock option within the meaning of Section 422 of the Code and the regulations
promulgated thereunder.

“NON-STATUTORY STOCK OPTION” means an Option not intended to qualify as an
Incentive Stock Option.

“OPTION” means a stock option granted pursuant to the Plan

“OPTIONEE” means an Employee, Director or Consultant who holds an outstanding
Option.

“OUTSIDE DIRECTOR” means a Director who either (a) is not a current Employee of
the Corporation or an “affiliated corporation” (within the meaning of Treasury
regulations promulgated under Section 162(m) of the Code), is not a former
Employee of the Corporation or an “affiliated corporation” receiving
compensation for prior services (other than benefits under a tax qualified
pension plan), was not an officer of the Corporation or an “affiliated
corporation” at any time, and is not currently receiving direct or indirect
remuneration from the Corporation or an “affiliated corporation” for services in
any capacity other than as a Director, or (b) is otherwise considered an
“outside director” for purposes of Section 162(m) of the Code.

“PLAN” means this Equity Incentive Plan, as amended and restated.

“SECURITIES ACT” means the Securities Act of 1933, as amended, and the
regulations promulgated thereunder.

“STOCK” means the Corporation’s Common Stock, $0.00001 par value per share, and
any security into which such Common Stock may be changed.

“STOCK PURCHASE AGREEMENT” means a written agreement between the Corporation and
a holder of an Equity Award evidencing the terms and conditions under which such
holder shall hold the shares of Stock awarded or purchased under the terms of
the Equity Award. Each Stock Purchase Agreement shall be subject to the terms
and conditions of the Plan and the Equity Award Agreement that evidenced the
bonus, award or Option.

“TERMINATION” means the termination of an Employee’s, Director’s or Consultant’s
employment or relationship with the Corporation or with any Affiliate of the
Corporation.

[End of Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan]

 

10

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AMENDMENT NO. 1

TO

AERPIO THERAPEUTICS, INC.

2011 EQUITY INCENTIVE PLAN

The Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan (the “Plan”) is hereby
amended by the Board of Directors and stockholders of Aerpio Therapeutics, Inc.,
a Delaware corporation (the “Corporation”), as follows:

Section 5.01 of the Plan is amended and restated to read in its entirety as
follows:

“Section 5.01 Authorized Shares. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, no more than 2,245,313 shares of
Stock may be issued pursuant to Equity Awards. All of the shares of Stock may be
issued in the form of Incentive Stock Options. The number of shares of Stock
reserved for issuance under this Plan may be increased from time to time as
permitted by law.”

 

ADOPTED BY BOARD OF DIRECTORS:

 

August 28, 2012

ADOPTED BY STOCKHOLDERS:

 

August 28, 2012

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

AMENDMENT NO. 2

TO

AERPIO THERAPEUTICS, INC.

2011 EQUITY INCENTIVE PLAN

The Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan (the “Plan”) is hereby
amended by the Board of Directors and stockholders of Aerpio Therapeutics, Inc.,
a Delaware corporation (the “Corporation”), as follows:

Section 5.01 of the Plan is amended and restated to read in its entirety as
follows:

“Section 5.01 Authorized Shares. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, no more than 3,075,763 shares of
Stock may be issued pursuant to Equity Awards. All of the shares of Stock may be
issued in the form of Incentive Stock Options. The number of shares of Stock
reserved for issuance under this Plan may be increased from time to time as
permitted by law.”

 

ADOPTED BY BOARD OF DIRECTORS:

 

August 23, 2013

ADOPTED BY STOCKHOLDERS:

 

August 23, 2013

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

AMENDMENT NO. 3

TO

AERPIO THERAPEUTICS, INC.

2011 EQUITY INCENTIVE PLAN

The Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan (the “Plan”) is hereby
amended by the Board of Directors and stockholders of Aerpio Therapeutics, Inc.,
a Delaware corporation (the “Corporation”), as follows:

Section 5.01 of the Plan is amended and restated to read in its entirety as
follows:

“Section 5.01 Authorized Shares. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, no more than 4,012,137 shares of
Stock may be issued pursuant to Equity Awards. All of the shares of Stock may be
issued in the form of Incentive Stock Options. The number of shares of Stock
reserved for issuance under this Plan may be increased from time to time as
permitted by law.”

 

ADOPTED BY BOARD OF DIRECTORS:

 

February 18, 2014

ADOPTED BY STOCKHOLDERS:

 

February 20, 2014

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

AMENDMENT NO. 4

TO

AERPIO THERAPEUTICS, INC.

2011 EQUITY INCENTIVE PLAN

The Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan (the “Plan”) is hereby
amended by the Board of Directors and stockholders of Aerpio Therapeutics, Inc.,
a Delaware corporation (the “Corporation”), as follows:

Section 5.01 of the Plan is amended and restated to read in its entirety as
follows:

“Section 5.01 Authorized Shares. Subject to the provisions of Article VIII
relating to adjustments upon changes in Stock, no more than 5,860,874 shares of
Stock may be issued pursuant to Equity Awards. All of the shares of Stock may be
issued in the form of Incentive Stock Options. The number of shares of Stock
reserved for issuance under this Plan may be increased from time to time as
permitted by law.”

 

ADOPTED BY BOARD OF DIRECTORS:

 

April 22, 2014

ADOPTED BY STOCKHOLDERS:

 

April 22, 2014

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EQUITY AWARD AGREEMENT—STOCK OPTIONS

(AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN)

AERPIO THERAPEUTICS, INC., a Delaware corporation (the “CORPORATION”), pursuant
to its 2011 EQUITY INCENTIVE PLAN (the “PLAN”), for good and valuable
consideration, hereby grants to the Optionee an option (the “OPTION”) to
purchase the number of shares of Stock set forth below. This Option is subject
to all of the terms and conditions set forth herein and in the Plan and the
Stock Purchase Agreement (each of which is attached hereto as Attachment A and
Attachment B, respectively, and is incorporated herein in its entirety).
Capitalized terms used herein but not defined are defined in the Plan.

 

Name of Optionee:   

 

Date of Grant:   

 

Vesting Commencement Date:   

 

Shares of Stock Subject to Option:   

 

Exercise Price Per Share:   

 

Expiration Date:    The earliest of: (a) the tenth anniversary of the Date of   
Grant, (b) twelve (12) months after notice of Termination    due to Disability
is delivered to you, (c) twelve (12)    months after the date of death in the
event of your    Termination due to death, (d) immediately, upon your   
Termination for Cause, (e) one (1) month after notice of    Termination for any
reason other than Cause, death or    Disability is delivered to you, or (f) upon
the effective date    of a Corporate Transaction if this Option is not assumed,
   or a substitute option is not issued, by the surviving    corporation. Upon
the Expiration Date, this Option will    automatically be cancelled and will be
of no further force    or effect to the extent not exercised prior thereto. FORM
OF OPTION        Incentive Stock Option        Non-statutory Stock Option
VESTING SCHEDULE.    Shares For Which Option is Exercisable:    After This
Period of Service (25% of Option Shares)    One-year anniversary of the Vesting
Commencement    Date. (75% of Option Shares)    Ratably on the first day of each
month between the one-    year anniversary of the Vesting Commencement Date and
   the fourth anniversary of the Vesting Commencement    Date (i.e., 2.0833% of
the total number of Option Shares    hereunder shall vest on the first day of
each such month).

In no event shall any shares of Stock subject to the Option vest after the
Optionee’s Termination, regardless of whether or not the Optionee was given
adequate notice of Termination of the Optionee’s employment by the Corporation
or by any Affiliate of the Corporation. Any shares of Stock subject to the
Option that remain unvested on the Optionee’s Termination shall be immediately
forfeited without compensation and without the requirement for any action on the
part of the Company or the Optionee.

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

ACCELERATION.

[Alternative 1—“Double Trigger”]

(a) OPTION ASSUMED. In the event that the surviving corporation (or a parent or
subsidiary of such corporation) in a Corporate Transaction assumes this Option
or issues a substitute option herefor, then solely in such event this Option or
the substitute option, as the case may be, shall become fully vested in the
event that, within twelve (12) months of the effective date of such Corporate
Transaction, the Optionee is terminated without Cause by the surviving
corporation or has his or her job responsibilities or duties, or base
compensation, materially diminished by such surviving corporation. Such vesting
acceleration shall take place automatically and immediately on the date on which
the Optionee receives notice of his or her termination without Cause or material
diminishment in job responsibilities or duties, or base compensation, as the
case may be, so that this Option or the substitute option, as the case may be,
shall be fully vested and fully and immediately exercisable as to all shares of
Stock subject hereto or thereto. In such case, the terms and conditions of this
Option or the substitute option shall survive such Corporate Transaction and
shall be otherwise applicable to the manner and circumstances under which this
Option or the substitute option may be exercised and shall expire.

(b) OPTION NOT ASSUMED. In the event that the surviving corporation (or a parent
or subsidiary of such corporation) in a Corporate Transaction does not assume
this Option or issue a substitute option herefor, and in the event that the
Board does not provide in substitution herefor such alternative consideration as
it, in good faith, may determine to be equitable in the circumstances, including
cash, then this Option shall become fully vested as of the effective date of
such Corporate Transaction (immediately prior to the consummation thereof), so
that this Option shall be fully and immediately exercisable as to all shares of
Stock subject hereto as of such effective date. Notice thereof shall be
delivered by the Corporation to the Optionee at least fifteen (15) days prior to
such effective date. Upon the effective date of such Corporate Transaction (in
connection with the consummation thereof), this Option shall terminate to the
extent not exercised prior thereto.

[Alternative 2—“Single Trigger”]

In the event of a Corporate Transaction, then this Option shall become fully
vested as of the effective date of such Corporate Transaction (immediately prior
to the consummation thereof), so that this Option shall be fully and immediately
exercisable as to all shares of Stock subject hereto as of such effective date.
Notice thereof shall be delivered by the Corporation to the Optionee at least
fifteen (15) days prior to such effective date. Upon the effective date of such
Corporate Transaction (in connection with the consummation thereof), this Option
shall terminate to the extent not exercised prior thereto.

[Alternative 3—Termination]

This Option shall terminate upon the effective date of a Corporate Transaction
to the extent not exercised prior thereto.

RULE 701. This Option is granted in connection with and in furtherance of the
Corporation’s compensatory benefit plan for the Corporation’s employees
(including officers), directors or consultants, and is intended to comply with
the provisions of Rule 701 promulgated by the Securities and Exchange Commission
under the Securities Act as well as all applicable state securities laws.

NOTIFICATION OF ISO SHARE DISPOSITION. If this Option is an Incentive Stock
Option, the Optionee hereby agrees to notify the Corporation in writing within
fifteen (15) days after the date of any disposition of any of the Stock issued
upon exercise of this Option that occurs within two (2) years after the Date of
Grant or within one (1) year after such Stock is acquired upon exercise of this
Option.

TRANSFERABILITY. The Optionee agrees that this Option is not transferable,
except by will or by the laws of descent and distribution, and is exercisable
during the Optionee’s life only by the Optionee, provided that if this Option is
a Non-statutory Stock Option, then the Optionee may transfer this Option, in
whole or in part, upon the prior written approval of the Board and in accordance
with applicable law.

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

NO EMPLOYMENT OR SERVICE CONTRACT. The Optionee agrees and understands that
nothing in this Equity Award Agreement or the Plan shall confer any right with
respect to the position, title, salary or duties with respect to the Optionee’s
employment with, or service to, the Corporation or the continuation thereof.

ADDITIONAL TERMS AND ACKNOWLEDGMENTS. The Optionee acknowledges receipt of, and
understands and agrees to, this Equity Award Agreement, the Plan and the Stock
Purchase Agreement. The Optionee understands that any Stock acquired under the
Option will be subject to the terms set forth in this Equity Award Agreement,
the Plan and the Stock Purchase Agreement. The Optionee further acknowledges
that as of the Date of Grant, this Equity Award Agreement, the Plan and the
Stock Purchase Agreement does and will set forth the entire understanding
between the Optionee and the Corporation regarding the acquisition of the Stock
subject hereto and does and will supersede all prior oral and written agreements
on that subject.

SIGNATURE PAGE FOLLOWS

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

AERPIO THERAPEUTICS, INC.     OPTIONEE By:         By:     Name:         Name:  
  Date:         Date:    

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

ATTACHMENT A

AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN

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

ATTACHMENT B

STOCK PURCHASE AGREEMENT

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

FORM STOCK PURCHASE AGREEMENT

(AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN)

 

To:   AERPIO THERAPEUTICS, INC.    Date of Exercise:        Ladies and
Gentlemen:     

PURCHASE. This constitutes notice under my Option that I elect to purchase the
number of shares of Stock indicated below (the “PURCHASED SHARES”) for the price
set forth below. Capitalized terms used herein but not defined are defined in
the Aerpio Therapeutics, Inc. 2011 Equity Incentive Plan.

 

Type of option (check one):    Incentive:                             
Non-statutory:          

 

DATE OF GRANT

  

NUMBER OF SHARES EXERCISED

  

EXERCISE PRICE PER SHARE

                                   

 

Total Exercise Price delivered herewith:      Certificates should be issued in
the following name:          

By this exercise, I agree (a) to provide such additional documents as you may
require pursuant to the terms of the Corporation’s 2011 Equity Incentive Plan
(the “PLAN”), including, but not limited to, a counterpart signature page to
each of the Corporation’s Stock Restriction Agreement and Voting Agreement, as
in effect from time to time, (b) 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 this option, (c) if this exercise relates to an Incentive Stock
Option, to notify you in writing within fifteen (15) days after the date of any
disposition of any of the Purchased Shares that occurs within two (2) years
after the date of grant of the Option or within one (1) year after such
Purchased Shares have been acquired upon exercise of the Option, (d) to furnish
to you any information, report and/or undertakings required to comply with the
laws, rules and regulations of all public agencies and authorities applicable to
the issuance and distribution of the Purchased Shares and to the listing
requirements of any stock exchange or exchanges on which the Purchased Shares
may be listed from time to time, and (e) to fully cooperate with you in
complying with such laws, rules and regulations.

In addition, I acknowledge and confirm that (a) I have the knowledge and
experience in financial and business matters necessary to exercise, and that I
am capable of evaluating, alone or together with a purchaser representative, the
merits and risks relating to the exercise of, my Option, and (b) that I am
acquiring the Purchased Shares for my own account and not with any view to a
distribution of the Purchased Shares.

RESTRICTED SECURITIES. I understand that the Purchased Shares have not been
registered under the Securities Act or any applicable state securities laws and
are being issued to me in reliance upon the exemption from such registration
provided by Rule 701 under the Securities Act for stock issuances under
compensatory benefit plans such as the Plan as well as under applicable state
securities laws. I hereby confirm that I have been informed that the Purchased
Shares are restricted securities under the Securities Act and under applicable
state securities laws and may not be resold or transferred unless the Purchased
Shares are first registered under the Federal securities laws and registered or
qualified under applicable state securities laws, unless an exemption from such
registration or qualification is available or unless I comply with the
requirements of Rule 144 promulgated under the Securities Act as well as the
requirements of applicable state securities laws. Accordingly, I hereby
acknowledge that I am

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

prepared to hold the Purchased Shares for an indefinite period and that I am
aware that Rule 144 promulgated under the Securities Act, which exempts certain
resales of restricted securities, may not be available to exempt the resale of
the Purchased Shares from the registration requirements of the Securities Act
and that similar exemptions may not be available under applicable state
securities laws.

The certificates representing the Purchased Shares shall bear the following
legend (and such other restrictive legends as are required or deemed advisable
under the provisions of any applicable law):

THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, OR UNDER ANY STATE SECURITIES LAWS. NEITHER
THIS SECURITY NOR ANY PORTION HEREOF OR INTEREST HEREIN MAY BE SOLD, ASSIGNED,
TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED OF UNLESS THE SAME IS REGISTERED
UNDER SAID ACT AND APPLICABLE STATE SECURITIES LAWS OR UNLESS AN EXEMPTION FROM
SUCH REGISTRATION IS AVAILABLE AND THE COMPANY HAS RECEIVED, AT THE EXPENSE OF
THE HOLDER HEREOF, EVIDENCE OF SUCH EXEMPTION REASONABLY SATISFACTORY TO THE
COMPANY (WHICH MAY INCLUDE, AMONG OTHER THINGS, AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY).

[Alternative 1—“Rights of Repurchase”]

RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE. I acknowledge and
agree that the Purchased Shares shall be subject to the following restrictions
on transferability and repurchase rights exercisable by the Corporation (and/or
its assignee(s)). The certificates representing the Purchased Shares shall bear
on their face the following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE IN FAVOR OF THE
CORPORATION AND/OR ITS ASSIGNEE(S) AS PROVIDED IN THE STOCK PURCHASE AGREEMENT
PURSUANT TO WHICH THE SECURITIES WERE ORIGINALLY ACQUIRED.

For the ninety (90) day period following the termination of my employment with
the Corporation for any reason, including death or Disability, with or without
Cause and whether voluntary or involuntary, the Corporation (and/or its
assignee(s)) shall have the right, but shall not be obligated, to purchase, and
I (or my estate or representative) shall be obligated to sell, all (but not less
than all) of the Purchased Shares on the terms hereinafter set forth.

The purchase price of the Purchased Shares (the “PURCHASE PRICE”) shall be
agreed upon by the Corporation (and/or its assignee(s)) and me (or my estate or
representative) within thirty (30) days after the Corporation (and/or its
assignee(s)) delivers written notice to me of its or their desire to purchase
the Purchased Shares. If we are unable to agree upon the Purchase Price within
that time period, then the Purchase Price, on a per-share basis, shall be the
Fair Market Value thereof. For purposes of the foregoing sentence, the valuation
date shall be the date on which the Corporation (and/or its assignee(s))
delivered notice to me of its or their intention to purchase the Purchased
Shares. The Corporation (and/or its assignee(s)) shall have the opportunity to
rescind its purchase offer within the ten (10) day period following the date
upon which the Purchase Price is finally determined.

The Purchase Price shall be paid to me at closing, which shall take place as
soon as is practicable after the Purchase Price is finally determined. At the
discretion of the Corporation (and/or its assignee(s)), the Purchase Price may
be paid (a) in full in cash at closing, or (b) by installment, by payment of no
less than twenty-five percent (25%) of the Purchase Price in cash at closing and
the balance by a promissory note with (i) a term no longer than three (3) years,
(ii) a pro rata payment schedule of principal and interest that is at least
semi-annual, and (iii) an interest rate that is at least ten percent (10%),
compounded annually. I agree that I will execute and deliver all instruments and
documents that the Corporation requests to effectively convey or transfer the
Purchase Shares.

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

Unless otherwise terminated by the Board, the foregoing restrictions on
transferability and rights of repurchase shall be terminated and of no further
force and effect upon the effective date of (a) the first underwritten
registration of the offering of any securities of the Corporation under the
Securities Act, or (b) the liquidation, dissolution or winding-up of the
Corporation (or the deemed liquidation, dissolution or winding-up of the
Corporation), as defined in and construed under the Corporation’s charter
documentation, as amended from time to time.

[Alternative 2—“No Rights of Repurchase”]

RESTRICTIONS ON TRANSFERABILITY. I acknowledge and agree that the Purchased
Shares shall be subject to the following restrictions on transferability
exercisable by the Corporation (and/or its assignee(s)). The certificates
representing the Purchased Shares shall bear on their face the following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
RESTRICTIONS ON TRANSFERABILITY IN FAVOR OF THE CORPORATION AND/OR ITS
ASSIGNEE(S) AS PROVIDED IN THE STOCK PURCHASE AGREEMENT PURSUANT TO WHICH THE
SECURITIES WERE ORIGINALLY ACQUIRED.

Unless otherwise terminated by the Board, the foregoing restrictions on
transferability shall be terminated and of no further force and effect upon the
effective date of (a) the first underwritten registration of the offering of any
securities of the Corporation under the Securities Act, or (b) the liquidation,
dissolution or winding-up of the Corporation (or the deemed liquidation,
dissolution or winding-up of the Corporation), as defined in and construed under
the Corporation’s charter documentation, as amended from time to time.

MARKET STAND-OFF. I agree that the Corporation (or a representative of its
underwriters) may, in connection with any underwritten registration of the
offering of any securities of the Corporation under the Securities Act, require
that I not sell or otherwise transfer or dispose of any shares of Stock or other
securities of the Corporation held by me during the period (not to exceed one
hundred eighty (180) days) following the effective date of the registration
statement of the Corporation filed under the Securities Act. I further agree
that the Corporation may impose stop-transfer instructions with respect to
securities subject to the foregoing restrictions until the end of such period.
The certificates representing the Purchased Shares shall bear on their face the
following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A “MARKET
STAND-OFF” AGREEMENT AS PROVIDED IN THE STOCK PURCHASE AGREEMENT PURSUANT TO
WHICH THE SECURITIES WERE ORIGINALLY ACQUIRED.

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

Very truly yours,  

 

  (Print Name)

 

AGREED AND ACCEPTED: AERPIO THERAPEUTICS, INC. By:     Name:     Date:    

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

EQUITY AWARD AGREEMENT – RESTRICTED STOCK AWARD

(AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN)

AERPIO THERAPEUTICS, INC., a Delaware corporation (the “CORPORATION”), pursuant
to its 2011 EQUITY INCENTIVE PLAN (the “PLAN”), for good and valuable
consideration, hereby grants to the undersigned grantee (the “GRANTEE”) a
restricted Stock award (the “AWARD”) for the number of shares of Stock set forth
below. This Award is subject to all of the terms and conditions set forth herein
and in the Plan, Right of First Refusal and Co-Sale Agreement and the Voting
Agreement (each of which is attached hereto as Attachment A, Attachment B and
Attachment C, respectively, and is incorporated herein in its entirety).
Capitalized terms used herein but not defined are defined in the Plan.

 

Name of Grantee:   

 

Date of Grant:   

 

Vesting Commencement Date:   

 

Shares of Stock Subject to Award:   

 

Purchase Price Per Share:   

 

VESTING SCHEDULE.    Vesting    After This Period of Service (25% of Stock
acquired hereunder)    One-year anniversary of the Vesting Commencement Date.
(75% of Stock acquired hereunder)    Ratably on the first day of each month
between the one-year anniversary of the Vesting Commencement Date and the fourth
anniversary of the Vesting Commencement Date (i.e., 2.0833% of the total number
of shares of Stock awarded hereunder shall vest on the first day of each such
month).

In no event shall any shares of Stock acquired hereunder vest after the
Grantee’s Termination, regardless of whether or not the Grantee was given
adequate notice of Termination of the Grantee’s employment by the Corporation or
by any Affiliate of the Corporation.

ACCELERATION.

[Alternative 1 – “Double Trigger”]

(a) AWARD ASSUMED. In the event that the surviving corporation (or a parent or
subsidiary of such corporation) in a Corporate Transaction assumes this Award or
issues a substitute award herefor, then solely in such event this Award or the
substitute award, as the case may be, shall become fully vested in the event
that, within twelve (12) months of the effective date of such Corporate
Transaction, the Grantee is terminated without Cause by the surviving
corporation or has his or her job responsibilities or duties, or base
compensation, materially diminished by such surviving corporation. Such vesting
acceleration shall take place automatically and immediately on the date on which
the Grantee receives notice of his or her termination without Cause or material
diminishment in job responsibilities or duties, or base compensation, as the
case may be, so that this Award or the substitute award, as the case may be,
shall be fully vested. In such case, the terms and conditions of this Award or
the substitute award shall survive such Corporate Transaction and shall be
otherwise applicable to the manner and circumstances under which this Award or
the substitute award may be exercised and shall expire.

(b) AWARD NOT ASSUMED. In the event that the surviving corporation (or a parent
or subsidiary of such corporation) in a Corporate Transaction does not assume
this Award or issue a substitute award herefor, and in the event that the Board
does not provide in substitution herefor such alternative consideration as it,
in good faith, may determine to be equitable in the circumstances, including
cash, then this Award shall become fully vested as of the effective date of such
Corporate Transaction (immediately prior to the consummation thereof). Notice
thereof shall be delivered by the Corporation to the Grantee at least fifteen
(15) days prior to such effective date.

 

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[Alternative 2 – “Single Trigger”]

In the event of a Corporate Transaction, then this Award shall become fully
vested as of the effective date of such Corporate Transaction (immediately prior
to the consummation thereof). Notice thereof shall be delivered by the
Corporation to the Grantee at least fifteen (15) days prior to such effective
date.

ACKNOWLEDGEMENTS. The Grantee hereby agrees (a) to provide such additional
documents as the Corporation may require pursuant to the Plan, including, but
not limited to, a counterpart signature page to each of the Corporation’s
Amended and Restated Right of First Refusal and Co-Sale Agreement and Amended
and Restated Voting Agreement, (b) to furnish to the Corporation any
information, report and/or undertakings required to comply with the laws, rules
and regulations of all public agencies and authorities applicable to the
issuance and distribution of the Stock acquired hereunder and to the listing
requirements of any stock exchange or exchanges on which the Stock acquired
hereunder may be listed from time to time, and (c) to fully cooperate with the
Corporation in complying with such laws, rules and regulations.

The Grantee hereby acknowledges and confirms that (a) the Grantee has the
knowledge and experience in financial and business matters necessary to acquire,
and that he or she is capable of evaluating, alone or together with a purchaser
representative, the merits and risks relating to the acquisition of, the Stock
acquired hereunder, and (b) that he or she is acquiring the Stock acquired
hereunder for his or her own account and not with any view to a distribution of
the Stock acquired hereunder.

The Grantee further acknowledges that he or she understands that the Stock
acquired hereunder has not been registered under the Securities Act or any
applicable state securities laws and is being issued to him or her in reliance
upon the exemption from such registration provided by Rule 701 under the
Securities Act for stock issuances under compensatory benefit plans such as the
Plan as well as under applicable state securities laws. The Grantee hereby
confirms that he or she has been informed that the Stock acquired hereunder is
restricted securities under the Securities Act and under applicable state
securities laws and may not be resold or transferred unless the Stock acquired
hereunder is first registered under the Federal securities laws and registered
or qualified under applicable state securities laws, unless an exemption from
such registration or qualification is available or unless the Grantee complies
with the requirements of Rule 144 promulgated under the Securities Act as well
as the requirements of applicable state securities laws. Accordingly, the
Grantee hereby acknowledges that he or she is prepared to hold the Stock
acquired hereunder for an indefinite period and that he or she is aware that
Rule 144 promulgated under the Securities Act, which exempts certain resales of
restricted securities, may not be available to exempt the resale of the Stock
acquired hereunder from the registration requirements of the Securities Act and
that similar exemptions may not be available under applicable state securities
laws.

The certificates representing the Stock acquired hereunder shall bear the
following legend (and such other restrictive legends as are required or deemed
advisable under the provisions of any applicable law):

THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, OR UNDER ANY STATE SECURITIES LAWS. NEITHER
THIS SECURITY NOR ANY PORTION HEREOF OR INTEREST HEREIN MAY BE SOLD, ASSIGNED,
TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED OF UNLESS THE SAME IS REGISTERED
UNDER SAID ACT AND APPLICABLE STATE SECURITIES LAWS OR UNLESS AN EXEMPTION FROM
SUCH REGISTRATION IS AVAILABLE AND THE COMPANY HAS RECEIVED, AT THE EXPENSE OF
THE HOLDER HEREOF, EVIDENCE OF SUCH EXEMPTION REASONABLY SATISFACTORY TO THE
COMPANY (WHICH MAY INCLUDE, AMONG OTHER THINGS, AN OPINION OF COUNSEL
SATISFACTORY TO THE COMPANY).

[Alternative 1 – “Rights of Repurchase”]

RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE. The Grantee
acknowledges and agrees that the Stock acquired hereunder shall be subject to
the following restrictions on transferability and repurchase rights exercisable
by the Corporation (and/or its assignee(s)). The certificates representing the
Stock acquired hereunder shall bear on their face the following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE IN FAVOR OF THE
CORPORATION AND/OR ITS ASSIGNEE(S) AS PROVIDED IN THE STOCK PURCHASE AGREEMENT
PURSUANT TO WHICH THE SECURITIES WERE ORIGINALLY ACQUIRED.

 

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For the ninety (90) day period following the Grantee’s Termination for any
reason, including death or Disability, with or without Cause and whether
voluntary or involuntary, the Corporation (and/or its assignee(s)) shall have
the right, but shall not be obligated, to purchase, and the Grantee (or his or
her estate or representative) shall be obligated to sell, all (but not less than
all) of the Stock acquired hereunder on the terms hereinafter set forth.

The purchase price of the unvested Stock shall be the original purchase price
therefor as set forth above. The purchase price of the vested Stock shall be
agreed upon by the Corporation (and/or its assignee(s)) and the Grantee (or his
or her estate or representative) within thirty (30) days after the Corporation
(and/or its assignee(s)) delivers written notice to the Grantee of its or their
desire to purchase the Stock acquired hereunder. If the purchase price for the
vested Stock is not agreed to within that time period, then the purchase price,
on a per-share basis, shall be the Fair Market Value thereof. For purposes of
the foregoing sentence, the valuation date shall be the date on which the
Corporation (and/or its assignee(s)) delivered notice to the Grantee of its or
their intention to purchase the Stock acquired hereunder. The Corporation
(and/or its assignee(s)) shall have the opportunity to rescind its purchase
offer within the ten (10) day period following the date upon which the purchase
price for the vested Stock is finally determined. The purchase price for the
unvested Stock and the purchase price for the vested Stock are collectively
referred to as the “PURCHASE PRICE.”

The Purchase Price shall be paid to the Grantee at closing, which shall take
place as soon as is practicable after the Purchase Price is finally determined.
At the discretion of the Corporation (and/or its assignee(s)), the Purchase
Price may be paid (a) in full in cash at closing, or (b) by installment, by
payment of no less than twenty-five percent (25%) of the Purchase Price in cash
at closing and the balance by a promissory note with (i) a term no longer than
three (3) years, (ii) a pro rata payment schedule of principal and interest that
is at least semi-annual, and (iii) an interest rate that is at least ten percent
(10%), compounded annually. The Grantee agrees that he or she will execute and
deliver all instruments and documents that the Corporation requests to
effectively convey or transfer the Stock.

Unless otherwise terminated by the Board, the foregoing restrictions on
transferability and rights of repurchase shall be terminated and of no further
force and effect upon the effective date of (a) the first underwritten
registration of the offering of any securities of the Corporation under the
Securities Act, or (b) the liquidation, dissolution or winding-up of the
Corporation (or the deemed liquidation, dissolution or winding-up of the
Corporation), as defined in and construed under the Corporation’s charter
documentation, as amended from time to time.

[Alternative 2 – “No Rights of Repurchase (Vested)”]

RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE. The Grantee
acknowledges and agrees that the Stock acquired hereunder shall be subject to
the following restrictions on transferability and repurchase rights exercisable
by the Corporation (and/or its assignee(s)). The certificates representing the
Stock acquired hereunder shall bear on their face the following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
RESTRICTIONS ON TRANSFERABILITY AND RIGHTS OF REPURCHASE IN FAVOR OF THE
CORPORATION AND/OR ITS ASSIGNEE(S) AS PROVIDED IN THE STOCK PURCHASE AGREEMENT
PURSUANT TO WHICH THE SECURITIES WERE ORIGINALLY ACQUIRED.

For the ninety (90) day period following the Grantee’s Termination for any
reason, including death or Disability, with or without Cause and whether
voluntary or involuntary, the Corporation (and/or its assignee(s)) shall have
the right, but shall not be obligated, to purchase, and the Grantee (or his or
her estate or representative) shall be obligated to sell, all (but not less than
all) of the unvested Stock acquired hereunder on the terms hereinafter set
forth.

The purchase price of the unvested Stock shall be the original purchase price
therefor as set forth above. The purchase price for the unvested Stock is
referred to as the “PURCHASE PRICE.”

 

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The Purchase Price shall be paid to the Grantee at closing, which shall take
place as soon as is practicable after the Purchase Price is finally determined.
At the discretion of the Corporation (and/or its assignee(s)), the Purchase
Price may be paid (a) in full in cash at closing, or (b) by installment, by
payment of no less than twenty-five percent (25%) of the Purchase Price in cash
at closing and the balance by a promissory note with (i) a term no longer than
three (3) years, (ii) a pro rata payment schedule of principal and interest that
is at least semi-annual, and (iii) an interest rate that is at least ten percent
(10%), compounded annually. The Grantee agrees that he or she will execute and
deliver all instruments and documents that the Corporation requests to
effectively convey or transfer the unvested Stock.

Unless otherwise terminated by the Board, the foregoing restrictions on
transferability and rights of repurchase shall be terminated and of no further
force and effect upon the effective date of (a) the first underwritten
registration of the offering of any securities of the Corporation under the
Securities Act, or (b) the liquidation, dissolution or winding-up of the
Corporation (or the deemed liquidation, dissolution or winding-up of the
Corporation), as defined in and construed under the Corporation’s charter
documentation, as amended from time to time.

MARKET STAND-OFF. The Grantee agrees that the Corporation (or a representative
of its underwriters) may, in connection with any underwritten registration of
the offering of any securities of the Corporation under the Securities Act,
require that the Grantee not sell or otherwise transfer or dispose of any shares
of Stock or other securities of the Corporation held by me during the period
(not to exceed one hundred eighty (180) days) following the effective date of
the registration statement of the Corporation filed under the Securities Act.
The Grantee further agrees that the Corporation may impose stop-transfer
instructions with respect to securities subject to the foregoing restrictions
until the end of such period. The certificates representing the Stock acquired
hereunder shall bear on their face the following legend:

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A “MARKET
STAND-OFF” AGREEMENT AS PROVIDED IN THE STOCK PURCHASE AGREEMENT PURSUANT TO
WHICH THE SECURITIES WERE ORIGINALLY ACQUIRED.

NO EMPLOYMENT OR SERVICE CONTRACT. The Grantee agrees and understands that
nothing in this Equity Award Agreement or the Plan shall confer any right with
respect to the position, title, salary or duties with respect to the Grantee’s
employment with, or service to, the Corporation or the continuation thereof.

ADDITIONAL TERMS AND ACKNOWLEDGMENTS. The Grantee acknowledges receipt of, and
understands and agrees to, this Equity Award Agreement, the Plan, the Amended
and Restated Right of First Refusal and Co-Sale Agreement and the Amended and
Restated Voting Agreement. The Grantee acknowledges and agrees that the
signature page to this Equity Award Agreement will also be fully effective as a
counterpart signature page to each of the Corporation’s Amended and Restated
Right of First Refusal and Co-Sale Agreement and Amended and Restated Voting
Agreement and that by executing and delivering this Equity Award Agreement, the
Grantee will, automatically and without the requirement of any further action,
be a party to the Corporation’s Amended and Restated Right of First Refusal and
Co-Sale Agreement and Amended and Restated Voting Agreement. The Grantee
understands that any Stock acquired under this Award will be subject to the
terms set forth in this Equity Award Agreement, the Plan, the Amended and
Restated Right of First Refusal and Co-Sale Agreement and the Amended and
Restated Voting Agreement. The Grantee further acknowledges that as of the Date
of Grant, this Equity Award Agreement, the Plan, the Amended and Restated Right
of First Refusal and Co-Sale Agreement and the Amended and Restated Voting
Agreement do and will set forth the entire understanding between the Grantee and
the Corporation regarding the acquisition of the Stock subject hereto and does
and will supersede all prior oral and written agreements on that subject. In the
event of any conflict or ambiguity between or among the provisions of this
Equity Award Agreement, the Plan, the Amended and Restated Right of First
Refusal and Co-Sale Agreement or the Amended and Restated Voting Agreement, the
provisions of this Equity Award Agreement will control.

SIGNATURE PAGE FOLLOWS

 

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AERPIO THERAPEUTICS, INC.     GRANTEE By:         By:     Name:         Name:  
  Date:         Date:    

 

- 5 -

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ATTACHMENT A

AERPIO 2011 EQUITY INCENTIVE PLAN

 

- 6 -

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ATTACHMENT B

RIGHT OF FIRST REFUSAL AND CO-SALE AGREEMENT

 

- 7 -

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ATTACHMENT C

VOTING AGREEMENT

 

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FORM OF STOCK PLEDGE AGREEMENT

(AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN)

STOCK PLEDGE AGREEMENT

THIS STOCK PLEDGE AGREEMENT (the “Agreement”) is made as of this      day of
            , 20    , by and between (“Pledgor”), and Aerpio Therapeutics, Inc.,
a Delaware corporation (“Lender”).

WHEREAS, Lender has extended a loan to Pledgor in the principal amount of $ (the
“Loan”), which Loan is evidenced by a promissory note in favor of Lender (the
“Note”); and

WHEREAS, to secure the payment and performance of all obligations under the
Note, Pledgor wishes to pledge to Lender all of Pledgor’s right, title and
interest in the capital stock of Lender owned by Pledgor and listed on Exhibit A
hereto (the “Stock”).

NOW, THEREFORE, the parties hereto agree as follows:

1. Warranty. Pledgor hereby represents and warrants to Lender that except for
the security interest created hereby, Pledgor owns the Stock free and clear of
all liens, charges and encumbrances, that the Stock is duly issued, fully paid
and nonassessable, and that Pledgor has the unencumbered right to pledge the
Stock.

2. Security Interest. Pledgor hereby unconditionally grants and assigns to
Lender, its successors and assigns, a continuing security interest in the
security title to the Stock. Pledgor has delivered to and deposited with Lender
herewith all of Pledgor’s right, title and interest in and to the Stock,
together with certificates representing the Stock and stock powers endorsed in
blank by Pledgor, as security for payment and performance of all obligations of
Pledgor to Lender under the Note or any extension, renewal, amendment or
modification of the Note, however created, acquired, arising or evidenced,
whether direct or indirect, absolute or contingent, now or hereafter existing,
or due or to become due. Beneficial ownership of the Stock, including, without
limitation, all voting, consensual and dividend rights, shall remain in Pledgor
until the occurrence of a Default under the terms hereof (as defined in
Section 4 below).

3. Additional Shares. In the event that, during the term of this Agreement:

(a) any stock dividend, stock split, reclassification, readjustment or other
change is declared or made in the capital structure of Lender, all new,
substituted and additional shares, or other securities, issued by reason of any
such change and received by Pledgor or to which Pledgor shall be entitled shall
be immediately delivered to Lender, together with stock powers endorsed in blank
by Pledgor, and shall thereupon constitute Stock to be held by Lender under the
terms of this Agreement; and

(b) subscriptions, warrants or any other rights or options are issued in
connection with the Stock, all new stock or other securities acquired through
such subscriptions, warrants, rights or options by Pledgor shall be immediately
delivered to Lender and shall thereupon constitute Stock to be held by Lender
under the terms of this Agreement.

4. Default. Failure of Pledgor to pay any amount of principal or interest when
due pursuant to the terms of the Note or a default by Pledgor under this
Agreement shall constitute a default under the terms of this Agreement (any of
such occurrences being hereinafter referred to as a “Default”). Upon the
occurrence of a Default, Lender may take the actions described in the following
sentence and thereafter, or may elect, as its sole recourse hereunder and under
the Note and full remedy hereunder and thereunder, in full settlement and
repayment of all amounts due and owing under the Note (the “Obligations”), and
without the requirement of Pledgor’s consent or approval, to redeem that number
of shares of Stock equal to the amount of the Obligations (or, if the
Obligations exceed the total value of the Stock, then all of the Stock), based
upon a price per share of the Stock equal to the fair market value thereof as
determined in the most recent third-party appraisal thereof. Alternatively,
Lender may sell or make other commercially reasonable disposition of the Stock
or any portion thereof after ten (10) business days’ written notice to Pledgor,
and Lender may purchase the Stock or any portion thereof at any public sale. The

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

proceeds of the public or private sale or other disposition shall be applied
(i) to the costs incurred in connection with the sale; (ii) to any unpaid
interest which may have accrued on any obligations secured hereby; (iii) to any
unpaid principal; and (iv) to damages incurred by Lender by reason of any breach
of the obligations secured against hereby, in such order as Lender may determine
but in any event the proceeds shall be applied first to the Non-Recourse Portion
of the Note (as defined in the Note) and then to the balance of the sums due
under the Note, and any remaining proceeds shall be paid over to Pledgor or
others as law provides. Pledgor shall not be liable to Lender for any deficiency
in the Non-Recourse Portion of the Note in the event the proceeds of the sale or
other disposition of the Stock are insufficient to pay such expenses, interest,
principal, obligations and damages.

5. Additional Rights of Secured Parties. In addition to other rights and
privileges under this Agreement, Lender shall have the rights, powers and
privileges of secured parties under the Uniform Commercial Code.

6. Return of Stock to Pledgor. Upon payment in full of all principal and
interest on the Note, Lender shall return to Pledgor all of the then remaining
Stock and all rights received by Lender as agent for Pledgor as a result of its
possessory interest in the Stock.

7. Voting Rights. Pledgor shall retain all rights to vote the Stock until such
time as Lender either cancels or sells the Stock after a Default under the Note.

8. Notices. All notices and other communications required or permitted hereunder
shall be in writing and, if mailed by prepaid certified mail, shall be deemed to
have been received on the earlier of the date shown on the receipt or three
(3) business days after the postmarked date thereof. In addition, notices
hereunder may be delivered by hand, by facsimile or by email, in which event
such notice shall be deemed effective when delivered. Notice of change of
address for notice shall also be governed by this Section. Notices shall be
addressed as follows:

 

If to Pledgor:    Name:                                                    
Mailing Address:                                                    
Facsimile:                                                    
Email:                                                  If to Lender:    Aerpio
Therapeutics, Inc.    Attention: CEO (or, if CEO is Pledgor, then CFO)   
Mailing Address:                                                    
Facsimile:                                                    
Email:                                                     With a copy to:

9. Binding Agreement. The provisions of this Agreement shall be construed and
interpreted, and all rights and obligations of the parties hereto determined, in
accordance with the laws of the State of Delaware. This Agreement, together with
all documents referred to herein, constitutes the entire agreement between
Pledgor and Lender with respect to the matters addressed herein and may not be
modified except by a writing executed by Lender and Pledgor. This Agreement may
be executed in multiple counterparts and by facsimile or PDF, each of which
shall be deemed an original but all of which, taken together, shall constitute
one and the same instrument.

10. Severability. If any paragraph or part thereof shall for any reason be held
or adjudged to be invalid, illegal or unenforceable by any court of competent
jurisdiction, such paragraph or part thereof so adjudicated invalid, illegal or
unenforceable shall be deemed separate, distinct and independent, and the
remainder of this Agreement shall remain in full force and effect and shall not
be affected by such holding or adjudication.

11. Assignability. This Agreement, and the rights and obligations of Lender
hereunder, may be assigned by Lender to any person or entity to which the Note
is transferred by Lender, and such transferee shall be deemed the “Lender” for
purposes of this Agreement; provided that the transferee provides written notice
of such assignment to Pledgor and agrees to be bound by the terms of this
Agreement.

Signature Page Follows

 

2

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IN WITNESS WHEREOF, the undersigned have hereunto set their hands, by and
through their duly authorized officers, as of the day and year first above
written.

 

  Pledgor:             (Signature)               (Print Name)   Lender:   Aerpio
Therapeutics, Inc.     By:          Its:    

 

3

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Exhibit A

STOCK CERTIFICATE NUMBERS

 

Number

  

Owner

  

Class of Shares

  

Number of Shares

Represented

                 

 

4

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Form of Partial Recourse Promissory Note

(AERPIO THERAPEUTICS, INC. 2011 EQUITY INCENTIVE PLAN)

PARTIAL RECOURSE PROMISSORY NOTE

 

$                                                             Cincinnati, Ohio
                           ,20        

FOR VALUE RECEIVED,                                      (“Borrower”) promises
to pay to Aerpio Therapeutics, Inc., a Delaware corporation (“Lender”), or
order, the principal sum of $                                     with interest
as set forth below, both principal and interest payable in lawful money of the
United States of America, at such place as Lender may designate in writing.

The principal and interest shall be due and payable as follows:

Interest shall accrue at the rate of six percent (6%) per annum from the date
hereof up to and through the date on which all principal and interest hereunder
is paid in full. Interest shall be paid yearly on the anniversary of this Note.
The entire aggregate unpaid principal balance and accrued but unpaid interest
shall be due and payable on the first to occur of (a) the consummation of
Lender’s first underwritten public offering of its Common Stock (other than a
registration statement relating either to the sale of securities to employees of
Lender pursuant to its stock option, stock purchase or similar plan or an SEC
Rule 145 transaction); (b) the consummation of a “Deemed Liquidation Event” and
distribution of proceeds to or escrow for the benefit of the stockholders of
Lender in accordance with Lender’s certificate of incorporation as in effect and
amended from time to time; (c) Borrower’s Termination (as such term is defined
in Lender’s 2011 Equity Incentive Plan as in effect and amended from time to
time); and (d) the fifth anniversary of the date hereof.

The Note may be prepaid in full or in part at any time without penalty or
premium; provided, however, that partial prepayments shall be applied first to
the payment of interest accrued to the date of such prepayment and then to the
payment of principal.

All parties to this Note, including maker and any sureties, endorsers or
guarantors, hereby waive protest, presentment, notice of dishonor and notice of
acceleration of maturity and agree to continue to remain bound for the payment
of principal, interest and all other sums due under this Note, notwithstanding
any change or changes by way of any extension or extensions of time for the
payment of principal and interest; and all such parties waive all and every kind
of notice of such change or changes and agree that the same may be made without
notice or consent of any of them.

As an inducement for Lender to accept from Borrower this Note and as collateral
security for the payment of any and all indebtedness and liabilities whatsoever
of Borrower to Lender evidenced by this Note, the parties hereto have executed a
certain Stock Pledge Agreement of even date herewith (the “Pledge Agreement”),
pursuant to which Borrower has delivered, assigned and pledged to Lender and has
granted to Lender a first priority security interest in [    ] shares of Common
Stock of Lender owned by Borrower (the “Stock”).

Upon default of Borrower in the payment of any indebtedness under this Note,
Lender’s sole recourse with respect to fifty percent (50%) of the sum of
(a) unpaid principal of this Note, (b) accrued but unpaid interest on this Note,
and (c) collection costs including attorneys’ fees in connection therewith (the
“Non-Recourse Portion”) shall be to exercise its rights under the Pledge
Agreement. Liability of Borrower under the Non-Recourse Portion of this Note is
limited to the shares held by Lender pursuant to the Pledge Agreement, and in no
event shall Borrower be liable on the Non-Recourse Portion of this Note for any
deficiency resulting from any sale of shares pursuant to the Pledge Agreement,
nor shall any action or proceeding be brought by Lender against Borrower to
recover judgment against Borrower upon the Non-Recourse Portion of this Note or
the Pledge Agreement. Upon default of Borrower in the payment of any
indebtedness under this Note, Borrower shall be fully liable for all amounts due
under this Note other than the Non-Recourse Portion.

 

1

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At the sole and absolute discretion of Borrower, Borrower may elect to repay
some or all of the amounts due and owing hereunder, at any time and from time to
time, whether in the event of Default or otherwise, and without the requirement
of Lender’s consent or approval, by putting to Lender that number of shares of
Stock equal to the amount of such repayment, based upon a price per share of the
Stock equal to the fair market value thereof as determined in the most recent
third-party appraisal thereof.

This Note is to be governed and construed in accordance with the laws of the
State of Delaware.

IN TESTIMONY WHEREOF, the undersigned has executed this instrument the day and
year first above written.

 

BORROWER           (Signature)       (Print Name)

 

2