Document:

EX-10.1

 Exhibit 10.1 

EXECUTIVE EMPLOYMENT AGREEMENT 

This EXECUTIVE EMPLOYMENT AGREEMENT (this “Agreement”) is entered into as of the 8th day of February, 2017 (the
“Execution Date”), between RICHARD P. SHEA (“Executive”) and SYNDAX PHARMACEUTICALS, INC. (the “Company”). Certain capitalized terms used in this Agreement are
defined in Article 7. 
 RECITALS 

A.    The Company is a biopharmaceutical company. 

B.    The Company desires to employ Executive in the position set forth below, and Executive wishes to be employed
by the Company in such position, upon the terms and conditions set forth in this Agreement. 
 AGREEMENT 

NOW, THEREFORE, in consideration of the mutual promises contained herein, the Company and Executive agree as follows: 

ARTICLE 1 
 PRELIMINARY
MATTERS 
 1.1    Effectiveness of Agreement. This Agreement shall be effective on the Execution Date.

 ARTICLE 2 
 TERMS
OF EMPLOYMENT 
 2.1    Appointment. Executive’s start date with the Company is February 13,
2017 or such other date as mutually agreed upon by the Company and Executive (the “Start Date”). Executive shall serve as Chief Financial Officer, reporting to the President and Chief Operating Officer. As Chief Financial
Officer, Executive will have such duties and responsibilities typically associated with such officer plus other reasonable duties as may from time to time be assigned to Executive. During Executive’s employment with the Company, Executive shall
(i) devote approximately eighty percent (80%) of Executive’s business efforts to the Company, provided, however, that Executive may (a) serve as a consultant to Momenta Pharmaceuticals, Inc., (b) participate in charitable,
civic, educational, professional, community or industry affairs, (c) manage Executive’s passive personal investments, and (d) serve as a board member, advisor or a similar position, of up to two other companies, so long as such
service does not conflict with or is not detrimental to the Company’s best interests, as determined in good faith by the Board, and (ii) faithfully and to the best of Executive’s abilities and experience, and in accordance with the
standards and ethics of the business in which the Company is engaged, perform all duties that may be required of Executive by this Agreement, the Company’s policies and procedures, and such other duties and responsibilities as may be assigned
to Executive from time to time, as well as the directives of the Board. During Executive’s employment with the Company, Executive shall not engage in any activity that conflicts with or is detrimental to the Company’s best interests, as
determined by the Board. Executive and the Company acknowledge that Executive’s primary office will be located at the Company’s Waltham, MA headquarters, but that Executive may be required to spend a certain amount of time each month at
the Company’s New York, NY office. 

 2.2    Employment Term. Executive will be employed by the
Company on an “at-will” basis. This means that either the Company or Executive may terminate Executive’s employment at any time, for any reason, with or without Cause, and with or without
advance notice (provided that Resignation for Good Reason (as defined below) requires certain advanced notice by Executive. It also means that Executive’s job title, duties, responsibilities, reporting level, compensation and benefits, as well
as the Company’s personnel policies and procedures, may be changed with or without notice at any time in the Company’s sole discretion. This at-will employment relationship shall not be modified by
any conflicting actions or representations of any Company employee or other party before or during the term of Executive’s employment. 

2.3    Compensation. 

a)    Annual Base Salary. Executive’s annual base salary shall be $325,000 per year (“Annual Base
Salary”), payable in equal installments, less applicable deductions and withholdings, in accordance with the Company’s standard payroll practices. Executive’s Annual Base Salary shall be subject to review by the Company’s
compensation committee and may be increased or decreased from time to time, but shall not be reduced unless, and only to the extent that, the base salaries of all other similarly situated executives of the Company are proportionately reduced. 

b)    Benefits. Executive will be entitled to participate in all of the employee benefits and benefit plans that
the Company generally makes available to its full-time employees and executives and for which Executive is eligible in accordance with the Company’s policies as in effect from time to time. These benefits are subject to the terms, conditions,
and eligibility requirements that govern or apply to them. 
 c)    Bonus. In addition to Annual Base Salary,
Executive shall be eligible to earn an annual performance bonus of up to thirty-five percent (35%) of Executive’s Annual Base Salary, which bonus shall be earned upon Executive’s attainment of objectives to be determined by the Board (or
the compensation committee thereof, as such determination may be delegated by the Board to the compensation committee) and continued employment with the Company as described below (the “Target Performance Bonus”). The amount
of and Executive’s eligibility for the Target Performance Bonus shall be determined in the sole discretion of the Board (or the compensation committee thereof, as such determination may be delegated by the Board to the compensation committee).
If earned, any Target Performance Bonus shall be paid to Executive, less authorized deductions and applicable withholdings, on or before the February 15th following the applicable bonus year. For the 2017 calendar year, if earned, the Target
Performance Bonus will be pro-rated from the Start Date. Except as provided in Sections 3.2 and 4.2, Executive shall be eligible to earn the Target Performance Bonus only if Executive is actively employed
and in good standing with the Company on both the determination and payment dates for the Target Performance Bonus. 

2.4    Reimbursement of Expenses. Subject to Section 5.10(c), the Company shall reimburse Executive for
Executive’s necessary and reasonable business expenses incurred in connection with Executive’s duties in accordance with the Company’s generally applicable policies. 

2.5    Grant of Stock Option. Subject to the approval of the Board or the compensation committee of the
Board, approximately upon the Start Date Executive will be issued an option to purchase 125,000 shares of the Company’s common stock (the “Option”). The Option will be evidenced by a stock option agreement and be subject
to the terms and conditions of the Company’s 2015 Equity 

  
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Incentive Plan, as amended (the “Equity Plan”). Subject to the terms and conditions of the Equity Plan, the Option will have a term of ten (10) years from the
Option’s grant date. The exercise price per share of the Option will be equal to the per share fair market value of the Company’s common stock on the date the Option is granted, as determined by the Board. The vesting schedule of the
Option will be as follows: twenty-five percent (25%) of the shares of the Company’s common stock subject to the Option will vest upon the one year anniversary of the Start Date, and one thirty-sixth (1/36th) of the remaining shares of the
Company’s common stock subject to the Option will vest each month thereafter on the last day of each month, so long as Executive remains an employee, consultant, director or officer of the Company, and subject to the terms and conditions of the
stock option agreement and the Equity Plan. 
 ARTICLE 3 

CHANGE IN CONTROL SEVERANCE BENEFITS 

3.1    Severance Benefits. Upon a Change in Control Termination, and subject to the limitations and
conditions set forth in this Agreement, Executive shall be eligible to receive the benefits set forth in this Article 3. The receipt of any severance payments or benefits pursuant to this Agreement is subject to Executive signing and not revoking a
separation agreement and general release of claims (the “Release”), in substantially the form attached hereto and incorporated herein as Exhibit A, Exhibit B or Exhibit C, as appropriate, which Release
must become effective and irrevocable no later than the sixtieth (60th) day following Executive’s termination of employment (the “Release Deadline Date”). If the
Release does not become effective and irrevocable by the Release Deadline Date, Executive will forfeit any right to any severance payments or benefits under this Agreement. In no event will severance payments or benefits be paid or provided until
the Release actually becomes effective and irrevocable 
 3.2    Salary and
Pro-Rata Bonus Payment. In consideration of Executive’s execution and non-revocation of the Release by the Release Deadline Date in a form provided by the
Company and in accordance with Article 4, the Company shall pay Executive a severance payment equal to (a) the sum of Executive’s Monthly Base Salary and Pro-Rata Bonus multiplied by (b) the
number of months in the Change in Control Severance Period, less applicable withholdings. The severance payment shall be payable (except as set forth in Article 5) in a lump sum on the first regularly-scheduled payroll date occurring on or after the
Release Deadline Date. 
 3.3    Health Continuation Coverage. 

a)    Provided that Executive is eligible and has made the necessary elections for continuation coverage pursuant to COBRA
under a health, dental or vision plan sponsored by the Company, the Company shall pay the applicable premiums (inclusive of premiums for Executive’s dependents for such health, dental or vision plan coverage as in effect immediately prior to
the date of the Change in Control Termination) for such continued health, dental or vision plan coverage following the date of the Change in Control Termination for up to the number of months equal to the Change in Control Benefits Period (but in no
event after such time as Executive is eligible for coverage under a health, dental or vision insurance plan of a subsequent employer or as Executive and Executive’s dependents are no longer eligible for COBRA coverage); provided that if
continued payment by the Company of the applicable premiums would result in a violation of the nondiscrimination rules of Section 105(h)(2) of the Internal Revenue Code of 1986, as amended, or any statute or regulation of similar effect
(including, without limitation, the 2010 Patient Protection and Affordable Care Act, as amended by the 2010 Health Care and Education Reconciliation Act), then in lieu of providing such continued payment, the Company will instead pay Executive on
the first day of each month a fully taxable cash payment equal to the applicable premiums for that month, subject to applicable tax withholdings, for the remainder of the Change in Control Benefits Period. Such coverage shall be counted as coverage
pursuant to COBRA. 

  
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The Company shall have no obligation in respect of any premium payments (or any other payments in respect of health, dental or vision coverage from the Company) following the effective date of
Executive’s coverage by a health, dental or vision insurance plan of a subsequent employer. Executive shall be required to notify the Company immediately if Executive becomes covered by a health, dental or vision insurance plan of a subsequent
employer. If Executive and Executive’s dependents continue coverage pursuant to COBRA following the conclusion of the Change in Control Benefits Period, Executive will be responsible for the entire payment of such premiums required under COBRA
for the duration of the COBRA period. 
 b)    For purposes of this Section 3.3, (i) references to COBRA shall
be deemed to refer also to analogous provisions of state law, and (ii) any applicable insurance premiums that are paid by the Company shall not include any amounts payable by Executive under a Code Section 125 health care reimbursement
plan, which amounts, if any, are the sole responsibility of Executive. 
 3.4    Stock Awards. Upon a
Change in Control Termination, (a) the vesting and exercisability of all outstanding options to purchase the Company’s common stock (or stock appreciation rights or other rights with respect to the stock of the Company issued pursuant to
any equity incentive plan of the Company) that are held by Executive on the Termination Date shall be accelerated in full, (b) any reacquisition or repurchase rights held by the Company with respect to common stock issued or issuable (or with
respect to other rights with respect to the stock of the Company issued or issuable) pursuant to any other stock award granted to Executive pursuant to any equity incentive plan of the Company shall lapse and (c) the time period that Executive
has to exercise any outstanding options to purchase the Company’s common stock that are held by Executive on the Termination Date shall be extended for a period equal to the shorter of (i) twelve (12) months or (ii) the remaining term
of the outstanding option. 
 ARTICLE 4 

COVERED TERMINATION SEVERANCE BENEFITS 

4.1    Severance Benefits. Upon a Covered Termination, and subject to the limitations and conditions set
forth in this Agreement, Executive shall be eligible to receive the benefits set forth in this Article 4. The receipt of any severance payments or benefits pursuant to this Agreement is subject to Executive signing and not revoking the appropriate
Release, which Release must become effective and irrevocable no later than the Release Deadline Date. If the Release does not become effective and irrevocable by the Release Deadline Date, Executive will forfeit any right to any severance payments
or benefits under this Agreement. In no event will severance payments or benefits be paid or provided until the Release actually becomes effective and irrevocable. 

4.2    Salary Payment. In consideration of Executive’s timely execution and non-revocation of the Release by the Release Deadline Date, the Company shall pay Executive a severance payment equal to Executive’s Monthly Base Salary multiplied by the number of months in the Covered
Termination Severance Period, less applicable withholdings. The severance payment shall be payable (except as set forth in Article 5) in a lump sum on the first regularly-scheduled payroll date occurring on or after the Release Deadline Date. 

4.3    Health Continuation Coverage. 

a)    Provided that Executive is eligible and has made the necessary elections for continuation coverage pursuant to COBRA
under a health, dental or vision plan sponsored by the Company, the Company shall pay for the applicable premiums (inclusive of premiums for Executive’s 

  
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dependents for such health, dental or vision plan coverage as in effect immediately prior to the date of the Covered Termination) for such continued health, dental or vision plan coverage
following the date of the Covered Termination for up to the number of months equal to the Covered Termination Benefits Period (but in no event after such time as Executive is eligible for coverage under a health, dental or vision insurance plan of a
subsequent employer or as Executive and Executive’s dependents are no longer eligible for COBRA coverage); provided that if continued payment by the Company of the applicable premiums would result in a violation of the nondiscrimination rules
of Section 105(h)(2) of the Internal Revenue Code of 1986, as amended, or any statute or regulation of similar effect (including, without limitation, the 2010 Patient Protection and Affordable Care Act, as amended by the 2010 Health Care and
Education Reconciliation Act), then in lieu of providing such continued payment, the Company will instead pay Executive on the first day of each month a fully taxable cash payment equal to the applicable premiums for that month, subject to
applicable tax withholdings, for the remainder of the Covered Termination Benefits Period. Such coverage shall be counted as coverage pursuant to COBRA. The Company shall have no obligation in respect of any premium payments (or any other payments
in respect of health, dental or vision coverage from the Company) following the effective date of Executive’s coverage by a health, dental or vision insurance plan of a subsequent employer. Executive shall be required to notify the Company
immediately if Executive becomes covered by a health, dental or vision insurance plan of a subsequent employer. If Executive and Executive’s dependents continue coverage pursuant to COBRA following the conclusion of the Covered Termination
Benefits Period, Executive will be responsible for the entire payment of such premiums required under COBRA for the duration of the COBRA period. 

b)    For purposes of this Section 4.3, (i) references to COBRA shall be deemed to refer also to analogous
provisions of state law, and (ii) any applicable insurance premiums that are paid by the Company shall not include any amounts payable by Executive under a Code Section 125 health care reimbursement plan, which amounts, if any, are the
sole responsibility of Executive. 
 4.4    Stock Awards. Upon a Covered Termination: 

a)    the vesting and exercisability of all outstanding options to purchase the Company’s common stock (or stock
appreciation rights or other rights with respect to the stock of the Company issued pursuant to any equity incentive plan of the Company) that are held by Executive on the Termination Date shall be accelerated as to the number of shares of common
stock issuable upon exercise of such option (“Option Shares”) as equals the number of Option Shares as would otherwise vest during the twelve (12) month period following the Termination Date in accordance with the
applicable options’ vesting schedule were the Executive to remain an employee of the Company during such twelve (12) month period (disregarding any other basis for acceleration of vesting of Option Shares during such twelve (12) month
period); 
 b)    any reacquisition or repurchase rights held by the Company with respect to common stock issued or
issuable (or with respect to other rights with respect to the stock of the Company issued or issuable) pursuant to any option to purchase the Company’s common stock (or stock appreciation rights or other rights with respect to the stock of the
Company) (“Restricted Shares”) held by the Executive as of the Termination Date shall lapse as to the number of Restricted Shares as equals the number of Restricted Shares as to which such reacquisition or repurchase rights
would otherwise lapse during the twelve (12) month period following the Termination Date in accordance with the option’s vesting schedule were the Executive to remain an employee of the Company during such twelve (12) month period
(disregarding any other basis for acceleration of the lapsing of such reacquisition or repurchase rights on Restricted Shares during such twelve (12) month period); and 

  
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 c)    the time period that Executive has to exercise any outstanding options
to purchase the Company’s common stock that are held by Executive on the Termination Date shall be extended for a period equal to the shorter of (i) twelve (12) months or (ii) the remaining term of the outstanding option. 

ARTICLE 5 
 LIMITATIONS
AND CONDITIONS ON BENEFITS 
 5.1    Rights Conditioned on Compliance. Executive’s rights to
receive all severance benefits described in Article 3 and Article 4 shall be conditioned upon and subject to Executive’s compliance with the limitations and conditions on benefits as described in this Article 5. 

5.2    Continuation of Service Until Date of Termination. Executive shall continue to provide service to the
Company in good faith until the Termination Date, unless such performance is otherwise excused in writing by the Company. 

5.3    Release Prior to Payment of Benefits. Upon the occurrence of a Change in Control Termination or a
Covered Termination, as applicable, and prior to Executive earning any entitlement to any severance or separation benefits under this Agreement on account of such Change in Control Termination or Covered Termination, as applicable, Executive must
execute the appropriate Release, and such Release must become effective in accordance with its terms, but in no event later than the Release Deadline Date. No amount shall be paid prior to such date. Instead, on the first regularly-scheduled payroll
date occurring on or after the Release Deadline Date, the Company will pay Executive the severance amount that Executive would otherwise have received on or prior to such date but for the delay in payment related to the effectiveness of the Release,
with the balance of the severance amount being paid as originally scheduled. The Company may modify the Release in its discretion to comply with changes in applicable law at any time prior to Executive’s execution of such Release. Such Release
shall specifically relate to all of Executive’s rights and claims in existence at the time of such execution and shall confirm Executive’s obligations under the Confidentiality Agreement and any similar obligations under applicable law. It
is understood that, as specified in the applicable Release, Executive has a certain number of calendar days to consider whether to execute such Release. If Executive does not execute and deliver such Release within the applicable period, no benefits
shall be provided or payable under this Agreement, and Executive shall have no further rights, title or interests in or to any severance benefits or payments pursuant to this Agreement. It is further understood that if Executive is age 40 or older
at the time of a Change in Control Termination or a Covered Termination, as applicable, Executive may revoke the applicable Release within seven (7) calendar days after its execution by Executive. If Executive revokes such Release within such
subsequent seven (7) day period, no benefits shall be provided or payable under this Agreement pursuant to such Change in Control Termination or Covered Termination, as applicable. 

5.4    Return of Company Property. Not later than the Termination Date, Executive shall return to the
Company all documents (and all copies thereof) and other property belonging to the Company that Executive has in his or her possession or control. The documents and property to be returned include, but are not limited to, all files, correspondence,
email, memoranda, notes, notebooks, records, plans, forecasts, reports, studies, analyses, compilations of data, proposals, agreements, financial information, research and development information, marketing information, operational and personnel
information, databases, computer-recorded information, tangible property and equipment (including, but not limited to, computers, facsimile machines, mobile telephones and servers), credit cards, entry cards, identification badges and keys, and any
materials of any kind which contain or embody any proprietary or confidential information of the Company (and all reproductions thereof in whole or in part). Executive 

  
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agrees to make a diligent search to locate any such documents, property and information. If Executive has used any personally owned computer, server or
e-mail system to receive, store, review, prepare or transmit any Company confidential or proprietary data, materials or information, then within ten (10) business days after the Termination Date,
Executive shall provide the Company with a computer-useable copy of all such information and then permanently delete and expunge such confidential or proprietary information from those systems. Executive agrees to provide the Company access to
Executive’s system as requested to verify that the necessary copying and/or deletion is done. 

5.5    Cooperation and Continued Compliance with Restrictive Covenants. 

a)    From and after the Termination Date, Executive shall cooperate fully with the Company in connection with its actual
or contemplated defense, prosecution or investigation of any existing or future litigation, arbitrations, mediations, claims, demands, audits, government or regulatory inquiries, or other matters arising from events, acts or failures to act that
occurred during the time period in which Executive was employed by the Company (including any period of employment with an entity acquired by the Company). Such cooperation includes, without limitation, being available upon reasonable notice,
without subpoena, to provide accurate and complete advice, assistance and information to the Company, including offering and explaining evidence, providing truthful and accurate sworn statements, and participating in discovery and trial preparation
and testimony. Executive also agrees to promptly send the Company copies of all correspondence (for example, but not limited to, subpoenas) received by Executive in connection with any such legal proceedings, unless Executive is expressly prohibited
by law from so doing. The Company will reimburse Executive for reasonable out-of-pocket expenses incurred in connection with any such cooperation (excluding foregone
wages, salary or other compensation) within thirty (30) days of Executive’s timely presentation of appropriate documentation thereof, in accordance with the Company’s standard reimbursement policies and procedures, and will make
reasonable efforts to accommodate Executive’s scheduling needs. 
 b)    From and after the Termination Date,
Executive shall continue to abide by all of the terms and provisions of the Confidentiality Agreement (and any other comparable agreement signed by Executive), in accordance with its terms. 

c)    Executive acknowledges and agrees that Executive’s obligations under this Section 5.5 are an essential
part of the consideration Executive is providing hereunder in exchange for which and in reliance upon which the Company has agreed to provide the payments and benefits under this Agreement. Executive further acknowledges and agrees that
Executive’s violation of this Section 5.5 inevitably would involve use or disclosure of the Company’s proprietary and confidential information. Accordingly, Executive agrees that Executive will forfeit, effective as of the date of any
breach, any right, entitlement, claim or interest in or to any unpaid portion of the severance payments or benefits provided in Article 3 or Article 4. If it is determined by a court of competent jurisdiction in any state that any restriction in
this Section 5.5 is excessive in duration or scope or is unreasonable or unenforceable under the laws of that state, it is the intention of the parties that such restriction may be modified or amended by the court to render it enforceable to
the maximum extent permitted by the law of that state. 
 5.6    Parachute Payments. 

a)    Parachute Payment Limitation. If any payment or benefit (including payments and benefits pursuant to this
Agreement) Executive would receive in connection with a Change in Control from the Company or otherwise (“Payment”) would (i) constitute a “parachute payment” within the meaning of Section 280G of the
Code, and (ii) but for this paragraph, be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then the Company shall cause to be determined, before any amounts of the Payment are paid
to Executive, which of the following two alternative forms of 

  
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payment shall be paid to Executive: (A) payment in full of the entire amount of the Payment (a “Full Payment”), or (B) payment of only a part of the Payment so
that Executive receives the largest payment possible without the imposition of the Excise Tax (a “Reduced Payment”). A Full Payment shall be made in the event that the amount received by Executive on a net after-tax basis is greater than what would be received by Executive on a net after-tax basis if the Reduced Payment were made, otherwise a Reduced Payment shall be made. If a
Reduced Payment is made, (i) the Payment shall be paid only to the extent permitted under the Reduced Payment alternative, and Executive shall have no rights to any additional payments and/or benefits constituting the Payment, and
(ii) reduction in payments and/or benefits shall occur in the following order: (A) reduction of cash payments; (B) cancellation of accelerated vesting of equity awards other than stock options; (C) cancellation of accelerated
vesting of stock options; and (D) reduction of other benefits paid to Executive. In the event that acceleration of compensation from Executive’s equity awards is to be reduced, such acceleration of vesting shall be canceled in the reverse
order of the date of grant. 
 b)    The independent registered public accounting firm engaged by the Company for
general audit purposes as of the day prior to the effective date of the Change in Control shall make all determinations required to be made under this Section 5.6. If the independent registered public accounting firm so engaged by the Company
is serving as accountant or auditor for the individual, entity or group effecting the Change in Control, the Company shall appoint a nationally recognized independent registered public accounting firm to make the determinations required hereunder.
The Company shall bear all expenses with respect to the determinations by such independent registered public accounting firm required to be made hereunder. 

c)    The independent registered public accounting firm engaged to make the determinations hereunder shall provide its
calculations, together with detailed supporting documentation, to the Company and Executive within fifteen (15) calendar days after the date on which Executive’s right to a Payment is triggered (if requested at that time by the Company or
Executive) or such other time as requested by the Company or Executive. If the independent registered public accounting firm determines that no Excise Tax is payable with respect to a Payment, either before or after the application of the Reduced
Amount, it shall furnish the Company and Executive with an opinion reasonably acceptable to Executive that no Excise Tax will be imposed with respect to such Payment. Any good faith determinations of the accounting firm made hereunder shall be
final, binding and conclusive upon the Company and Executive. 
 5.7    Certain Reductions and Offsets. To
the extent that any federal, state or local laws, including, without limitation, the Worker Adjustment and Retraining Notification Act or any other so-called “plant closing” laws, require the Company
to give advance notice or make a payment of any kind to Executive because of Executive’s involuntary termination due to a layoff, reduction in force, plant or facility closing, sale of business, change in control or any other similar event or
reason, the benefits payable under this Agreement shall be correspondingly reduced. The benefits provided under this Agreement are intended to satisfy any and all statutory obligations that may arise out of Executive’s involuntary termination
of employment for the foregoing reasons, and the parties shall construe and enforce the terms of this Agreement accordingly. 

5.8    Mitigation. Except as otherwise specifically provided herein, Executive shall not be required to
mitigate damages or the amount of any payment provided under this Agreement by seeking other employment or otherwise, nor shall the amount of any payment provided for under this Agreement be reduced by any compensation earned by Executive as a
result of employment by another employer or by any retirement benefits received by Executive after the date of a Change in Control Termination or Covered Termination (except as expressly provided in Sections 3.3 and 4.3 above).

  
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 5.9    Indebtedness of Executive. If Executive is indebted to
the Company on the effective date of a Change in Control Termination or Covered Termination, the Company reserves the right to offset any severance payments and benefits under this Agreement by the amount of such indebtedness. 

5.10    Application of Section 409A. 

a)    Separation from Service. Notwithstanding any provision to the contrary in this Agreement, no amount deemed
deferred compensation subject to Section 409A of the Code shall be payable pursuant to Article 3 or Article 4 unless Executive’s termination of employment constitutes a “separation from service” with the Company within the
meaning of Section 409A of the Code and the Department of Treasury Regulations and other guidance promulgated thereunder and, except as provided under Section 5.10(b) hereof, any such amount shall not be paid, or in the case of
installments, commence payment, until the first regularly-scheduled payroll date occurring on or after the sixtieth (60th) day following Executive’s separation from service. Any installment
payments that would have been made to Executive during the sixty (60) day period immediately following Executive’s separation from service but for the preceding sentence shall be paid to Executive on the first regularly-scheduled payroll
date occurring on or after the sixtieth (60th) day after Executive’s separation from service and the remaining payments shall be made as provided in this Agreement. 

b)    Specified Executive. Notwithstanding any provision to the contrary in this Agreement, if Executive is deemed
at the time of his or her separation from service to be a “specified employee” for purposes of Section 409A(a)(2)(B)(i) of the Code, to the extent delayed commencement of any portion of the benefits to which Executive is entitled
under this Agreement is required in order to avoid a prohibited distribution under Section 409A(a)(2)(B)(i) of the Code, such portion of Executive’s benefits shall not be provided to Executive prior to the earlier of (i) the
expiration of the six (6)-month period measured from the date of Executive’s “separation from service” with the Company (as such term is defined in the Treasury Regulations issued under Section 409A of the Code) or (ii) the
date of Executive’s death. Upon the first business day following the expiration of the applicable Code Section 409A(a)(2)(B)(i) period, all payments deferred pursuant to this Section 5.10(b) shall be paid in a lump sum to Executive,
and any remaining payments due under this Agreement shall be paid as otherwise provided herein. 
 c)    Expense
Reimbursements. To the extent that any reimbursement payable pursuant to this Agreement is subject to the provisions of Section 409A of the Code, any such reimbursement payable to Executive pursuant to this Agreement shall be paid to
Executive no later than December 31 of the year following the year in which the expense was incurred; the amount of expenses reimbursed in one year shall not affect the amount eligible for reimbursement in any subsequent year; and
Executive’s right to reimbursement under this Agreement will not be subject to liquidation or exchange for another benefit. 

d)    Installments. For purposes of Section 409A of the Code (including, without limitation, for purposes of
Treasury Regulation Section 1.409A-2(b)(2)(iii)), Executive’s right to receive any installment payments under this Agreement shall be treated as a right to receive a series of separate payments and,
accordingly, each such installment payment shall at all times be considered a separate and distinct payment. 

5.11    Tax Withholding. All payments under this Agreement shall be subject to applicable withholding for
federal, state and local income and employment taxes. 
 5.12    No Duplication of Severance Benefits. The
severance and other benefits provided in Article 3 and Article 4 are mutually exclusive of each other, and in no event shall Executive receive any severance or other benefits pursuant to both Article 3 and Article 4. 

  
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 ARTICLE 6 

TERMINATION WITH CAUSE OR BY VOLUNTARY RESIGNATION; 

OTHER RIGHTS AND BENEFITS 

6.1    Termination for Cause by the Company. If the Company shall terminate the Executive’s employment
with the Company for Cause, then upon such termination, the Company shall have no further obligation to Executive hereunder except for the payment or provision, as applicable, of (a) the portion of the Annual Base Salary for the period prior to
the effective date of termination earned but unpaid (if any), (b) all unreimbursed expenses (if any), subject to Sections 2.4 and 5.10(c), and (c) other payments, entitlements or benefits, if any, in accordance with terms of the applicable
plans, programs, arrangements or other agreements of the Company (other than any severance plan or policy) as to which the Executive held rights to such payments, entitlements or benefits, whether as a participant, beneficiary or otherwise on the
date of termination (“Other Benefits”). For the avoidance of doubt, Executive shall have no right to receive (and Other Benefits shall not include) any amounts under any Company severance plan or policy or pursuant to Article
3 or Article 4 upon Executive’s termination for Cause. 
 6.2    Termination by Voluntary Resignation by
the Executive (other than Resignation for Good Reason). Upon any voluntary resignation by Executive that is not a Resignation for Good Reason, the Company shall have no further obligation to the Executive hereunder except for the payment of
(a) the portion of the Annual Base Salary for the period prior to the effective date of termination earned but unpaid (if any), (b) all unreimbursed expenses (if any), subject to Sections 2.4 and 5.10(c), and (c) the payment or provision
of any Other Benefits. For the avoidance of doubt, Executive shall have no right to receive (and Other Benefits shall not include) any amounts under any Company severance plan or policy or pursuant to Article 3 or Article 4 upon any voluntary
resignation by Executive that is not a Resignation for Good Reason. 
 6.3    Other Rights and Benefits.
Nothing in this Agreement shall prevent or limit Executive’s continuing or future participation in any benefit, bonus, incentive or other plans, programs, policies or practices provided by the Company and for which Executive may
otherwise qualify, nor shall anything herein limit or otherwise affect such rights as Executive may have under other agreements with the Company except as provided in Article 2, Article 5, Section 6.1 and Section 6.2 above. Except as
otherwise expressly provided herein, amounts that are vested benefits or that Executive is otherwise entitled to receive under any plan, policy, practice or program of the Company at or subsequent to the date of a Change in Control shall be payable
in accordance with such plan, policy, practice or program. 
 ARTICLE 7 

DEFINITIONS 
 Unless
otherwise provided, for purposes of this Agreement, the following definitions shall apply: 

7.1    “Board” means the Board of Directors of the Company. 

7.2    “Cause” means, upon a reasonable determination by the Company, Executive’s:
(a) dishonest statements or acts with respect to the Company, any subsidiary or any affiliate of the Company or any subsidiary; (b) commission by or indictment for (i) a felony or (ii) any misdemeanor (excluding minor traffic
violations) involving moral turpitude, deceit, dishonesty or fraud (“indictment,” for these purposes, meaning an indictment, probable cause hearing or any other procedure pursuant to which an initial determination of probable or reasonable
cause with respect to such offense is made); 

  
 10 

 
(c) gross negligence, willful misconduct or insubordination with respect to the Company, any subsidiary or any affiliate of the Company or any subsidiary; (d) material breach of any of
Executive’s obligations under any agreement to which Executive and the Company or any subsidiary are a party; or (e) death or disability. With respect to clause (d), Executive will be given notice and a
30-day period in which to cure such breach, only to the extent such breach can be reasonably expected to be able to be cured within such period. Executive agrees that the breach of any confidentiality
obligation to the Company or any subsidiary shall not be curable to any extent. 
 7.3    “Change in
Control” means the occurrence, in a single transaction or in a series of related transactions, of any one or more of the following events: 

a)    Any natural person, entity or group within the meaning of Section 13(d) or 14(d) of the Securities Exchange Act
of 1934, as amended (“Exchange Act Person”), becomes the owner, directly or indirectly, of securities of the Company representing more than fifty percent (50%) of the combined voting power of the Company’s then
outstanding securities other than by virtue of a merger, consolidation or similar transaction. Notwithstanding the foregoing, a Change in Control shall not be deemed to occur (i) on account of the acquisition of securities of the Company by any
institutional investor, any affiliate thereof or any other Exchange Act Person that acquires the Company’s securities in a transaction or series of related transactions that are primarily a private financing transaction for the Company or
(ii) solely because the level of ownership held by any Exchange Act Person (the “Subject Person”) exceeds the designated percentage threshold of the outstanding voting securities as a result of a repurchase or other
acquisition of voting securities by the Company reducing the number of shares outstanding, provided that if a Change in Control would occur (but for the operation of this sentence) as a result of the acquisition of voting securities by the Company,
and after such share acquisition, the Subject Person becomes the owner of any additional voting securities that, assuming the repurchase or other acquisition had not occurred, increases the percentage of the then outstanding voting securities owned
by the Subject Person over the designated percentage threshold, then a Change in Control shall be deemed to occur; 

b)    There is consummated a merger, consolidation or similar transaction involving, directly or indirectly, the Company
if, immediately after the consummation of such merger, consolidation or similar transaction, the stockholders of the Company immediately prior thereto do not own, directly or indirectly, either (i) outstanding voting securities representing
more than fifty percent (50%) of the combined outstanding voting power of the surviving entity in such merger, consolidation or similar transaction or (ii) more than fifty percent (50%) of the combined outstanding voting power of the
parent of the surviving entity in such merger, consolidation or similar transaction; 
 c)    The stockholders of the
Company approve or the Board approves a plan of complete dissolution or liquidation of the Company, or a complete dissolution or liquidation of the Company shall otherwise occur; or 

d)    There is consummated a sale, lease, license or other disposition of all or substantially all of the consolidated
assets of the Company and its subsidiaries, other than a sale, lease, license or other disposition of all or substantially all of the consolidated assets of the Company and its subsidiaries to an entity, more than fifty percent (50%) of the
combined voting power of the voting securities of which are owned by stockholders of the Company in substantially the same proportion as their ownership of the Company immediately prior to such sale, lease, license or other disposition. 

The term Change in Control shall not include a sale of assets, merger or other transaction effected exclusively for the purpose of changing
the domicile of the Company. Notwithstanding the foregoing or any other provision of this Agreement, the definition of Change in Control (or any analogous term) in an individual written agreement between the Company or any affiliate and the
participant shall 

  
 11 

 
supersede the foregoing definition with respect to stock awards subject to such agreement (it being understood, however, that if no definition of Change in Control or any analogous term is set
forth in such an individual written agreement, the foregoing definition shall apply). 

7.4    “Change in Control Benefits Period” means the period of twelve (12) months
commencing on the Termination Date. 
 7.5    “Change in Control Severance Period” means
the period of twelve (12) months commencing on the Termination Date. 
 7.6    “Change in Control
Termination” means an “Involuntary Termination Without Cause” or “Resignation for Good Reason,” either of which occurs on, or within three (3) months prior to, or within twelve
(12) months following, the effective date of a Change in Control, provided that any such termination is a “separation from service” within the meaning of Treasury Regulation
Section 1.409A-1(h). Death and disability shall not be deemed Change in Control Terminations. 

7.7    “COBRA” means the Consolidated Omnibus Budget Reconciliation Act of 1985, as
amended. 
 7.8    “Code” means the Internal Revenue Code of 1986, as amended. 

7.9    “Company” means Syndax Pharmaceuticals, Inc. or, following a Change in Control, the
surviving entity resulting from such transaction, or any subsequent surviving entity resulting from any subsequent Change in Control. 

7.10    “Confidentiality Agreement” means Executive’s Assignment of Developments, Non-Disclosure, and Non-Solicitation Agreement with the Company (or any successor agreement thereto). 

7.11    “Covered Termination” means an “Involuntary Termination Without
Cause” or “Resignation for Good Reason,” provided that any such termination is a “separation from service” within the meaning of Treasury Regulation
Section 1.409A-1(h). Death and disability shall not be deemed Covered Terminations. If an Involuntary Termination Without Cause or Resignation for Good Reason qualifies as a Change in Control Termination,
it shall not constitute a Covered Termination. 
 7.12    “Covered Termination Benefits
Period” means the period of twelve (12) months commencing on the Termination Date. 

7.13    “Covered Termination Severance Period” means the period of six (6) months
commencing on the Termination Date. 
 7.14    “Involuntary Termination Without Cause”
means Executive’s dismissal or discharge by the Company for reasons other than Cause and other than as a result of death or disability. 

7.15    “Monthly Base Salary” means
1/12th of the greater of (i) Executive’s annual base salary (excluding incentive pay, premium pay, commissions, overtime, bonuses and other forms of variable compensation) as in effect
on the date of a Change in Control Termination or a Covered Termination, as applicable, or (ii) in the case of a Change in Control Termination, Executive’s annual base salary (excluding incentive pay, premium pay, commissions, overtime,
bonuses and other forms of variable compensation) as in effect on the date of a Change in Control. 

  
 12 

 7.16    “Pro-Rata
Bonus” means 1/12th of the greater of (i) the average Target Performance Bonus paid to Executive for the three years preceding the date of a Change in Control Termination (or
such lesser number of years during which Executive has been employed by the Company), or (ii) the Target Performance Bonus, as in effect on the date of a Change in Control Termination. 

7.17    “Resignation for Good Reason” means Executive’s resignation from all employee
positions Executive then holds with the Company within sixty (60) days following any of the following events taken without Executive’s consent, provided Executive has given the Company written notice of such event within thirty
(30) days after the first occurrence of such event and the Company has not cured such event within thirty (30) days thereafter: 

a)    A decrease in Executive’s total target cash compensation (base and bonus) of more than 10% (i.e., a material
reduction in Executive’s base compensation and a material breach by the Company of Executive’s employment terms with the Company), other than in connection with a comparable decrease in compensation for all comparable executives of the
Company; 
 b)    Executive’s duties or responsibilities are materially diminished (not simply a change in title or
reporting relationships); provided, that Executive shall not be deemed to have a “Resignation for Good Reason” if the Company survives as a separate legal entity or business unit following the Change in Control and Executive
holds materially the same position in such legal entity or business unit as Executive held before the Change in Control; 

c)    Either (i) Executive is required to establish residence in a location more than fifty (50) miles from
Executive’s current principal personal residence or (ii) there is an increase in Executive’s round-trip driving distance of more than fifty (50) miles from Executive’s current principal personal residence to the principal
office or business location at which Executive is required to perform services (except for required business travel to the extent consistent with Executive’s prior business travel obligations) (“Executive’s Principal Place of
Business”) as a result of a change in location by the Company of Executive’s Principal Place of Business; or 

d)    The failure of the Company to obtain a satisfactory agreement from any successor to materially assume and materially
agree to perform under the terms of this Agreement. 
 7.18    “Termination Date” means
the effective date of the Change in Control Termination, the Covered Termination or a termination for Cause, as applicable. 
 ARTICLE 8

 GENERAL PROVISIONS 

8.1    Employment Status. This Agreement does not constitute a contract of employment or impose upon
Executive any obligation to remain as an employee, or impose on the Company any obligation (i) to retain Executive as an employee, (ii) to change the status of Executive as an at-will employee or
(iii) to change the Company’s policies regarding termination of employment. 
 8.2    Notices.
Any notices provided hereunder must be in writing, and such notices or any other written communication shall be deemed effective upon the earlier of personal delivery (including personal delivery by facsimile) or the third day after mailing by first
class mail, to the Company at its primary office location and to Executive at Executive’s address as listed in the Company’s payroll records. Any payments made by the Company to Executive under the terms of this Agreement shall be
delivered to Executive either in person or at the address as listed in the Company’s payroll records. 

  
 13 

 8.3    Severability. Whenever possible, each provision of this
Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any
jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or
unenforceable provisions had never been contained herein. 
 8.4    Waiver. If either party should waive
any breach of any provisions of this Agreement, he, she or it shall not thereby be deemed to have waived any preceding or succeeding breach of the same or any other provision of this Agreement. 

8.5    Complete Agreement. This Agreement, including Exhibit A, Exhibit B and Exhibit
C, and the Confidentiality Agreement constitute the entire agreement between Executive and the Company and is the complete, final and exclusive embodiment of their agreement with regard to this subject matter, wholly superseding all written and
oral agreements with respect to payments and benefits to Executive in the event of employment termination. It is entered into without reliance on any promise or representation other than those expressly contained herein. 

8.6    Amendment or Termination of Agreement; Continuation of Agreement. This Agreement may be changed or
terminated only upon the mutual written consent of the Company and Executive. The written consent of the Company to a change or termination of this Agreement must be signed by an executive officer of the Company (other than Executive) after such
change or termination has been approved by the Board. Unless so terminated, this Agreement shall continue in effect for as long as Executive continues to be employed by the Company or by any surviving entity following any Change in Control. In other
words, if, following a Change in Control, Executive continues to be employed by the surviving entity without a Change in Control Termination and the surviving entity then undergoes a Change in Control, following which Executive is terminated by the
subsequent surviving entity in a Change in Control Termination, then Executive shall receive the benefits described in Article 3 hereof. 

8.7    Counterparts. This Agreement may be executed in separate counterparts, any one of which need not
contain signatures of more than one party, but all of which taken together will constitute one and the same Agreement. 

8.8    Headings. The headings of the Articles and Sections hereof are inserted for convenience only and
shall not be deemed to constitute a part hereof nor to affect the meaning thereof. 
 8.9    Successors and
Assigns. This Agreement is intended to bind and inure to the benefit of and be enforceable by Executive, and the Company, and any surviving entity resulting from a Change in Control and upon any other person who is a successor by merger,
acquisition, consolidation or otherwise to the business formerly carried on by the Company, and their respective successors, assigns, heirs, executors and administrators, without regard to whether or not such person actively assumes any rights or
duties hereunder; provided, however, that Executive may not assign any duties hereunder and may not assign any rights hereunder without the written consent of the Company, which consent shall not be withheld unreasonably. 

8.10    Choice of Law. Because of the Company’s and Executive’s interests in ensuring that
disputes regarding this Agreement are resolved on a uniform basis, the parties agree that all questions concerning the construction, validity and interpretation of this Agreement will be governed by the law of the State of New York, without regard
for any conflict of law principles. Further, the parties consent to the jurisdiction of the state and federal courts of the State of New York for all purposes in connection with this Agreement. The parties hereby irrevocably waive, to the fullest
extent permitted by applicable law, any objection which Executive or the Company may now or hereafter have to the laying of venue of any such dispute brought in such court or any defense of inconvenient forum for the maintenance of such dispute.

  
 14 

 8.11    Arbitration. To ensure the rapid and economical
resolution of any disputes that may arise under or relate to this Agreement or Executive’s employment relationship, Executive and the Company agree that any and all disputes, claims, or causes of action, in law or equity, arising from or
relating to the performance, enforcement, execution, or interpretation of this Agreement, Executive’s employment with the Company, or the termination of Executive’s employment (collectively, “Claims”), shall be
resolved to the fullest extent permitted by law, by final, binding, and (to the extent permitted by law) confidential arbitration before a single arbitrator in the state where Executive is employed. The arbitration shall be governed by the
Federal Arbitration Act, 9 U.S.C. Section 1 et seq., as amended, and shall be administered by the Judicial Arbitration & Mediation Services, Inc. (“JAMS”), in accordance with its then-current Employment
Arbitration Rules & Procedures (the “JAMS Rules”). The JAMS Rules are also available online at http://www.jamsadr.com/rules-employment-arbitration/. The parties or their representatives may also call
JAMS at 800.352.5267 if they have questions about the arbitration process. If the JAMS Rules are inconsistent with the terms of this Agreement, the terms of this Agreement shall govern. Notwithstanding the foregoing, this provision shall
exclude Claims that by law are not subject to arbitration. The arbitrator shall: (a) have the authority to compel adequate discovery for the resolution of all Claims and to award such relief as would otherwise be permitted by law; and
(b) issue a written arbitration decision including the arbitrator’s essential findings and conclusions and a statement of the award. The Company shall pay all JAMS fees in excess of the amount of filing and other court-related fees
Executive would have been required to pay if the Claims were asserted in a court of law. EXECUTIVE AND THE COMPANY UNDERSTAND AND FULLY AGREE THAT BY ENTERING INTO THIS AGREEMENT, BOTH EXECUTIVE AND THE COMPANY ARE GIVING UP THE CONSTITUTIONAL
RIGHT TO HAVE A TRIAL BY JURY, AND ARE GIVING UP THE NORMAL RIGHTS OF APPEAL FOLLOWING THE RENDERING OF A DECISION, EXCEPT AS THE FEDERAL ARBITRATION ACT AND APPLICABLE FEDERAL LAW ALLOW FOR JUDICIAL REVIEW OF ARBITRATION PROCEEDINGS. Nothing in
this Agreement shall prevent either Executive or the Company from obtaining injunctive relief in court to prevent irreparable harm pending the conclusion of any such arbitration. Any awards or final orders in such arbitrations may be entered
and enforced as judgments or orders in the federal and state courts of any competent jurisdiction in compliance with Section 8.11 of this Agreement. 

8.12    Construction of Agreement. In the event of a conflict between the text of this Agreement and any
summary, description or other information regarding this Agreement, the text of this Agreement shall control. 

8.13    Circular 230 Disclaimer. THE FOLLOWING DISCLAIMER IS PROVIDED IN ACCORDANCE WITH THE INTERNAL REVENUE
SERVICE’S CIRCULAR 230 (21 C.F.R. PART 10). ANY TAX ADVICE CONTAINED IN THIS AGREEMENT IS INTENDED TO BE PRELIMINARY, FOR DISCUSSION PURPOSES ONLY AND NOT FINAL. ANY SUCH ADVICE IS NOT INTENDED TO BE USED FOR MARKETING, PROMOTING OR
RECOMMENDING ANY TRANSACTION OR FOR THE USE OF ANY PERSON IN CONNECTION WITH THE PREPARATION OF ANY TAX RETURN. ACCORDINGLY, THIS ADVICE IS NOT INTENDED OR WRITTEN TO BE USED, AND IT CANNOT BE USED, BY ANY PERSON FOR THE PURPOSE OF AVOIDING TAX
PENALTIES THAT MAY BE IMPOSED ON SUCH PERSON. 

  
 15 

 IN WITNESS WHEREOF, the parties have executed this Agreement on the dates below. 

 

									
	SYNDAX PHARMACEUTICALS, INC.	 		 		 	EXECUTIVE
					
	By:	 	 /s/ Briggs W. Morrison, M.D.
	 		 	By:	 	 /s/ Richard P. Shea

	Name:	 	Briggs W. Morrison, M.D.	 		 	Name:	 	Richard P. Shea
	Title:	 	Chief Executive Officer	 		 	Date:	 	February 8, 2017
	Date:	 	February 8, 2017	 		 		 	

 Exhibit A:    Release (Individual Termination – Age 40 or Older)  

Exhibit B:    Release (Individual and Group Termination – Under Age 40) 

Exhibit C:    Release (Group Termination – Age 40 or Older) 

  
 16 

 EXHIBIT A 

RELEASE 
 (INDIVIDUAL
TERMINATION – AGE 40 OR OLDER) 
 Certain capitalized terms used in this Release are defined in the Executive Employment Agreement
(the “Agreement”) which I have executed and of which this Release is a part. 
 I hereby confirm my obligations
under the Confidentiality Agreement (or other comparable agreement that I have signed, if any). 
 Except as otherwise set forth in this
Release, I hereby release, acquit and forever discharge the Company, its parents and subsidiaries, and their officers, directors, agents, servants, employees, shareholders, successors, assigns and affiliates, of and from any and all claims,
liabilities, demands, causes of action, costs, expenses, attorneys’ fees, damages, indemnities and obligations of every kind and nature, in law, equity or otherwise, known and unknown, suspected and unsuspected, disclosed and undisclosed (other
than any claim for indemnification I may have as a result of any third party action against me based on my employment with the Company), arising out of or in any way related to agreements, events, acts or conduct at any time prior to the date I
execute this Release, including, but not limited to: all such claims and demands directly or indirectly arising out of or in any way connected with my employment with the Company or the termination of that employment, including, but not limited to,
claims of intentional and negligent infliction of emotional distress, any and all tort claims for personal injury, claims or demands related to salary, bonuses, commissions, stock, stock options, or any other ownership interests in the Company,
vacation pay, fringe benefits, expense reimbursements, severance pay, or any other form of compensation; and claims pursuant to any federal, state or local law or cause of action including, but not limited to, the federal Civil Rights Act of 1964,
as amended, the federal Age Discrimination in Employment Act of 1967, as amended (“ADEA”), the federal Employee Retirement Income Security Act of 1974, as amended, the federal Americans with Disabilities Act of 1990, the
California Fair Employment and Housing Act, as amended, the New York City Human Rights Law, as amended, the Massachusetts Fair Employment Practices Law, as amended, the South Carolina Human Affairs Law, as amended, tort law, contract law, wrongful
discharge, discrimination, fraud, defamation, emotional distress, and breach of the implied covenant of good faith and fair dealing; provided, however, that nothing in this paragraph shall be construed in any way to (1) release the Company from
its obligation to indemnify me pursuant to the Company’s indemnification obligation pursuant to written agreement or applicable law; (2) release any claim by me against the Company relating to the validity or enforceability of this release
or the Agreement; (3) prohibit me from exercising any non-waivable right to file a charge with the United States Equal Employment Opportunity Commission (“EEOC”), the
National Labor Relations Board (“NLRB”), or any other government agency (provided, however, that I shall not be entitled to recover any monetary damages or to obtain non-monetary relief
if the agency were to pursue any claims relating to my employment with the Company). 
 I acknowledge that I am knowingly and voluntarily
waiving and releasing any rights I may have to assert claims for age discrimination under applicable law, including under the ADEA. I also acknowledge that the consideration given under the Agreement for the waiver and release in the preceding
paragraph hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that: (A) my waiver and release do not apply to any rights or claims
that may arise on or after the date I execute this Release; (B) I have the right to consult with an attorney prior to executing this Release; (C) I have twenty-one (21) days to consider this
Release (although I may choose to voluntarily execute this Release earlier); (D) I have seven (7) days following my execution of this Release to revoke the Release by providing a written notice

  
 A-1 

 
of revocation to the Company’s Chief Executive Officer; and (E) this Release shall not be effective until the date upon which the revocation period has expired, which shall be the
eighth (8th) day after I execute this Release (provided that I do not revoke it). 
 I hereby represent that I have been paid all
compensation owed and for all hours worked, I have received all the leave and leave benefits and protections for which I am eligible, pursuant to the federal Family and Medical Leave Act, any Company policy or applicable law, and I have not suffered
any on-the-job injury or illness for which I have not already filed a workers’ compensation claim. 

I agree that I will not make any disparaging statements regarding the Company or its officers, directors, shareholders, members, agents or
products jointly or severally. The foregoing shall not be violated by truthful statements in response to legal process, required governmental testimony or filings, or administrative or arbitral proceedings (including, without limitation, depositions
in connection with such proceedings). 
  

			
	EXECUTIVE:
	
	  

	Signature
	
	  

	Printed Name
		
	Date:	 	                                      
                                         
              

  
 A-2 

 EXHIBIT B 

RELEASE 
 (INDIVIDUAL
AND GROUP TERMINATION – UNDER AGE 40) 
 Certain capitalized terms used in this Release are defined in the Executive Employment
Agreement (the “Agreement”) which I have executed and of which this Release is a part. 
 I hereby confirm my
obligations under the Confidentiality Agreement (or other comparable agreement that I have signed, if any). 
 Except as otherwise set forth
in this Release, I hereby release, acquit and forever discharge the Company, its parents and subsidiaries, and their officers, directors, agents, servants, employees, shareholders, successors, assigns and affiliates, of and from any and all claims,
liabilities, demands, causes of action, costs, expenses, attorneys’ fees, damages, indemnities and obligations of every kind and nature, in law, equity or otherwise, known and unknown, suspected and unsuspected, disclosed and undisclosed (other
than any claim for indemnification I may have as a result of any third party action against me based on my employment with the Company), arising out of or in any way related to agreements, events, acts or conduct at any time prior to the date I
execute this Release, including, but not limited to: all such claims and demands directly or indirectly arising out of or in any way connected with my employment with the Company or the termination of that employment, including, but not limited to,
claims of intentional and negligent infliction of emotional distress, any and all tort claims for personal injury, claims or demands related to salary, bonuses, commissions, stock, stock options, or any other ownership interests in the Company,
vacation pay, fringe benefits, expense reimbursements, severance pay, or any other form of compensation; and claims pursuant to any federal, state or local law or cause of action including, but not limited to, the federal Civil Rights Act of 1964,
as amended, the federal Employee Retirement Income Security Act of 1974, as amended, the federal Americans with Disabilities Act of 1990, the California Fair Employment and Housing Act, as amended, the New York City Human Rights Law, as amended, the
Massachusetts Fair Employment Practices Law, as amended, the South Carolina Human Affairs Law, as amended, tort law, contract law, wrongful discharge, discrimination, fraud, defamation, emotional distress, and breach of the implied covenant of good
faith and fair dealing; provided, however, that nothing in this paragraph shall be construed in any way to (1) release the Company from its obligation to indemnify me pursuant to the Company’s indemnification obligation pursuant to
written agreement or applicable law; (2) release any claim by me against the Company relating to the validity or enforceability of this release or the Agreement; (3) prohibit me from exercising any
non-waivable right to file a charge with the United States Equal Employment Opportunity Commission (“EEOC”), the National Labor Relations Board (“NLRB”), or any
other government agency (provided, however, that I shall not be entitled to recover any monetary damages or to obtain non-monetary relief if the agency were to pursue any claims relating to my employment with
the Company). 
 I acknowledge that the consideration given under the Agreement for the waiver and release in the preceding paragraph hereof
is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing that: (A) my waiver and release do not apply to any rights or claims that may arise on or after the date I
execute this Release; (B) I have the right to consult with an attorney prior to executing this Release; and (C) I have twenty-one (21) days to consider this Release (although I may choose to
voluntarily execute this Release earlier). 
 I hereby represent that I have been paid all compensation owed and for all hours worked, I
have received all the leave and leave benefits and protections for which I am eligible, pursuant to the federal Family and Medical Leave Act, any Company policy or applicable law, and I have not suffered any on-the-job injury or illness for which I have not already filed a workers’ compensation claim. 

  
 B-1 

 I agree that I will not make any disparaging statements regarding the Company or its officers,
directors, shareholders, members, agents or products jointly or severally. The foregoing shall not be violated by truthful statements in response to legal process, required governmental testimony or filings, or administrative or arbitral proceedings
(including, without limitation, depositions in connection with such proceedings). 
  

			
	EXECUTIVE:
	
	  

	Signature
	
	  

	Printed Name
		
	Date:	 	                                      
                                         
              

  
 B-2 

 EXHIBIT C 

RELEASE 
 (GROUP
TERMINATION – AGE 40 OR OLDER) 
 Certain capitalized terms used in this Release are defined in the Executive Employment Agreement
(the “Agreement”) which I have executed and of which this Release is a part. 
 I hereby confirm my obligations
under the Confidentiality Agreement (or other comparable agreement that I have signed, if any). 
 Except as otherwise set forth in this
Release, I hereby release, acquit and forever discharge the Company, its parents and subsidiaries, and their officers, directors, agents, servants, employees, shareholders, successors, assigns and affiliates, of and from any and all claims,
liabilities, demands, causes of action, costs, expenses, attorneys’ fees, damages, indemnities and obligations of every kind and nature, in law, equity or otherwise, known and unknown, suspected and unsuspected, disclosed and undisclosed (other
than any claim for indemnification I may have as a result of any third party action against me based on my employment with the Company), arising out of or in any way related to agreements, events, acts or conduct at any time prior to the date I
execute this Release, including, but not limited to: all such claims and demands directly or indirectly arising out of or in any way connected with my employment with the Company or the termination of that employment, including, but not limited to,
claims of intentional and negligent infliction of emotional distress, any and all tort claims for personal injury, claims or demands related to salary, bonuses, commissions, stock, stock options, or any other ownership interests in the Company,
vacation pay, fringe benefits, expense reimbursements, severance pay, or any other form of compensation; and claims pursuant to any federal, state or local law or cause of action including, but not limited to, the federal Civil Rights Act of 1964,
as amended, the federal Age Discrimination in Employment Act of 1967, as amended (“ADEA”), the federal Employee Retirement Income Security Act of 1974, as amended, the federal Americans with Disabilities Act of 1990, the
California Fair Employment and Housing Act, as amended, the New York City Human Rights Law, as amended, the Massachusetts Fair Employment Practices Law, as amended, the South Carolina Human Affairs Law, as amended, tort law, contract law, wrongful
discharge, discrimination, fraud, defamation, emotional distress, and breach of the implied covenant of good faith and fair dealing; provided, however, that nothing in this paragraph shall be construed in any way to (1) release the Company from
its obligation to indemnify me pursuant to the Company’s indemnification obligation pursuant to written agreement or applicable law; (2) release any claim by me against the Company relating to the validity or enforceability of this release
or the Agreement; (3) prohibit me from exercising any non-waivable right to file a charge with the United States Equal Employment Opportunity Commission (“EEOC”), the National
Labor Relations Board (“NLRB”), or any other government agency (provided, however, that I shall not be entitled to recover any monetary damages or to obtain non-monetary relief if the
agency were to pursue any claims relating to my employment with the Company). 
 I acknowledge that I am knowingly and voluntarily waiving
and releasing any rights I may have to assert claims for age discrimination under applicable law, including under the ADEA. I also acknowledge that the consideration given under the Agreement for the waiver and release in the preceding paragraph
hereof is in addition to anything of value to which I was already entitled. I further acknowledge that I have been advised by this writing, as required by the ADEA, that: (A) my waiver and release do not apply to any rights or claims that may
arise on or after the date I execute this Release; (B) I have the right to consult with an attorney prior to executing this Release; (C) I have forty-five (45) days to consider this Release (although I may choose to voluntarily
execute this Release earlier); (D) I have seven (7) days following my execution of this Release to revoke the Release by providing a written notice of 

  
 C-1 

 
revocation to the Company’s Chief Executive Officer; (E) this Release shall not be effective until the date upon which the revocation period has expired, which shall be the eighth day
(8th) after I execute this Release; and (F) I have received with this Release the required written disclosure for a “group termination” under the ADEA, including a detailed list of the job titles and ages of all employees who
were terminated in this group termination and the ages of all employees of the Company in the same job classification or organizational unit who were not terminated. 

I hereby represent that I have been paid all compensation owed and for all hours worked, I have received all the leave and leave benefits and
protections for which I am eligible, pursuant to the federal Family and Medical Leave Act, any Company policy or applicable law, and I have not suffered any on-the-job
injury or illness for which I have not already filed a workers’ compensation claim. 
 I agree that I will not engage in any conduct
that is injurious to the reputation of the Company or its parents, subsidiaries and affiliates, including but not limited to disparagement of the Company, its officers, Board members, employees and shareholders. The foregoing shall not be violated
by a statement made in a deposition, trial or administrative proceeding in response to legal process; by any statement made to a government agency; or whenever I make any statement to a court, administrative tribunal or government agency as required
by law.
  

			
	EXECUTIVE:
	
	  

	Signature
	
	  

	Printed Name
		
	Date:	 	                                     
                                         
               

  
 C-2EX-10.2

 Exhibit 10.2 

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SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

AMENDMENT NO. 1 TO CLINICAL TRIAL COLLABORATION 

AND SUPPLY AGREEMENT 
 (FOR NON-SMALL CELL LUNG CANCER STUDY WITH EXPANSION COHORTS 
 IN
NON-SMALL CELL LUNG CANCER, MELANOMA, AND COLORECTAL CANCER) 
 This Amendment No. 1 to the CLINICAL TRIAL
COLLABORATION AND SUPPLY AGREEMENT (this “Amendment No. 1”), made as of April 26, 2017 (the “Amendment Effective Date”), is entered into by and between Merck Sharp & Dohme
B.V., having a place of business at Waarderweg 39, 2031 BN Haarlem, Netherlands, and MSD International GmbH, having a place of business at Weystrasse 20, 6000 Luzern 6, Switzerland (together, “Merck”), and Syndax Pharmaceuticals,
Inc., having a place of business at 35 Gatehouse Drive, Building D, Floor 3, Waltham, MA 02451 (“Syndax”). Merck and Syndax are each referred to herein individually as a “Party” and collectively as the
“Parties”. 
 WHEREAS, the Parties entered into a Clinical Trial Collaboration and Supply Agreement dated as of
March 27, 2015, covering a Phase 1b/2, open-label, dose escalation study of the Syndax Compound in combination with the Merck Compound in patients with non-small cell lung cancer, with expansion cohorts
in patients with non-small cell lung cancer and melanoma (the “Agreement”); and 

WHEREAS, the Parties desire to add an additional expansion cohort to the study contemplated by the Agreement and to make certain amendments to
the Agreement in connection therewith, all on the terms and conditions set forth in this Amendment No. 1. 
 NOW, THEREFORE, the
Parties hereby agree as follows: 
  

	1	Certain Definitions. Capitalized terms used in this Amendment No. 1 and not defined herein shall have the meanings given to them in the Agreement. 

 

	2	Amendments to the Agreement. 

  

	 	2.1	Section 1.50 of the Agreement is hereby deleted in its entirety and replaced with the following: 

  

	 	“1.50	‘Study’ means a Phase 1b/2, open-label, dose escalation study of the Syndax Compound in combination with the Merck Compound in patients with non-small cell lung
cancer, with expansion cohorts in patients with non-small cell lung cancer, melanoma, and mismatch repair-proficient colorectal cancer.” 

  
 1 

	 	2.2	Section 4.1 of the Agreement is hereby amended by deleting the first sentence thereof and replacing it with the following: 

“A Protocol, entitled ‘A Phase 1b/2, Open-Label, Dose Escalation Study of Eninostat in Combination with Pembrolizumab in Patients
with Non-Small Cell Lung Cancer, with Expansion Cohorts in Patients with Non-Small Cell Lung Cancer, Melanoma, and Mismatch Repair-Proficient Colorectal Cancer’ has
been agreed to by the Parties as of April 13, 2017, the synopsis of which is attached as Appendix A.” 
  

	 	2.3	A new Section 4.4 is hereby added to the Agreement as follows: 

  

	 	“4.4	Transparency Reporting. 

 4.4.1. With respect to any
annual reporting period in which Company is not an entity that is required to make a Transparency Report under Applicable Law, Company will: (a) notify Merck, in writing, within *** after the commencement of such reporting period that Company is not
so required; and (b) during such reporting period Company will track and provide to Merck data regarding “indirect” payments or other transfers of value by Company to such health care professionals to the extent such payments or other
transfers of value were required, instructed, directed or otherwise caused by Merck pursuant to this Agreement in the format requested by Merck and provided on a basis to be agreed upon by both Parties. Company represents and warrants that any data
provided by Company to Merck pursuant to Section 4.4.1(b) above will be complete and accurate to the best of Company’s knowledge. 

4.4.2. With respect to any annual reporting period in which Company is required to make a Transparency Report under Applicable
Law, Company will provide to Merck, in writing, Company’s point of contact for purposes of receiving information from Merck pursuant to this Section 4.4, along with such contact’s full name, email address, and telephone number. Company may
update such contact from time to time by notifying Merck in writing pursuant to Section 22 (Notices). Where applicable, Merck will provide to such Company contact all information regarding the value of the Merck Compound provided for use in the
Study required for such reporting. In the event that the value of the Merck Compound provided pursuant to this Section 4.4.2 changes, Merck shall notify Company of such revised value and the effective date thereof. 

4.4.3. For purposes of this Section 4.4, “Transparency Report” means a transparency report in connection with
reporting payments and other transfers of value made to health care professionals, including, without limitation, investigators, steering committee members, data monitoring committee members, and consultants in connection with the Study in
accordance with reporting requirements under Applicable Law, 

  

					
	

	 	2	 	

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WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 
including, without limitation, the Physician Payment Sunshine Act and state gift laws, and the European Federation of Pharmaceutical Industries and Associations Disclosure Code, or a Party’s
applicable policies.” 
  

	 	2.4	Section 22 of the Agreement is hereby deleted in its entirety and replaced with the following: 

  

	 	“22.	Notices. 

 All notices or other communications that are required or
permitted hereunder shall be in writing and delivered personally, sent by facsimile (and promptly confirmed by personal delivery or overnight courier), or sent by internationally-recognized overnight courier addressed as follows: 

If to Merck, to: 
 MSD
International GmbH 
 Weystrasse 20 

6000 Luzern 
 Switzerland 

Attention: Director 
 Facsimile:
*** 
 -and- 
 Merck
Sharp & Dohme B.V. 
 Waarderweg 39 

2031 BN Haarlem 
 Netherlands

 Attention: Director 

Facsimile: *** 
 With a copy
(which shall not constitute notice) to: 
 Merck Sharp & Dohme Corp. 

One Merck Drive 
 P.O. Box 100

 Whitehouse Station, NJ 08889-0100 

Attention: Office of Secretary 

Facsimile No.: *** 

  

					
	

	 	3	 	

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WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 If to Syndax, to: 

Syndax Pharmaceuticals, Inc. 

35 Gatehouse Drive 
 Building D,
Floor 3 
 Waltham, MA 02451 

Facsimile No.: (781) 419-1420” 

 

	 	2.5	Appendix A of the Agreement is hereby deleted in its entirety and replaced with the new Appendix A attached to this Amendment No. 1 as Schedule 1. 

 

	 	2.6	Appendix B of the Agreement is hereby deleted in its entirety and replaced with the new Appendix B attached to this Amendment No. 1 as Schedule 2. 

 

	3	Press Release. On or immediately after the Amendment Effective Date, Syndax will issue a press release in the form attached hereto as Schedule 3. 

 

	4	General. Except as specifically modified or amended by this Amendment No. 1, the terms and conditions of the Agreement remain unchanged and in full force and effect. All references in the Agreement to the
“Agreement” shall mean the Agreement as modified by this Amendment No. 1. This Amendment No. 1 shall be governed by and construed in accordance with the substantive laws of the State of New York, without giving effect to its
choice of law principles. This Amendment No. 1 may be executed in two (2) or more counterparts (including by way of facsimile or electronic transmission), each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument. For clarity, facsimile signatures and signatures transmitted via PDF shall be treated as original signatures. 

[Remainder of page intentionally left blank.] 
  

  

					
	

	 	4	 	

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WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 IN WITNESS WHEREOF, the respective authorized representatives of the Parties have executed this
Amendment No. 1 as of the Amendment Effective Date. 
  

			
	Syndax Pharmaceuticals, Inc.
		
	By:	 	 /s/ Michael A. Metzger

			
	
	 Michael A. Metzger

	Name	 	
	
	 President & Chief Operating Officer

	Title	 	
	
	MSD International GmbH

			
		
	By:	 	 ***

			
	
	 ***

	Name	 	
	
	 ***

	Title	 	
	
	Merck Sharp & Dohme B.V.

			
		
	By:	 	 ***

			
	
	 ***

	Name	 	
	
	 ***

	Title	 	

  
 *** INDICATES MATERIAL THAT WAS
OMITTED AND FOR WHICH CONFIDENTIAL TREATMENT WAS REQUESTED. ALL SUCH OMITTED MATERIAL WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 Schedule 1 

Appendix A 
 PROTOCOL SYNOPSIS

 *** 

  

					
	

	 		 	

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MATERIAL WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 Schedule 2 

Appendix B 
 SUPPLY OF COMPOUND

 *** 

  
 *** INDICATES 1 PAGE OF MATERIAL THAT
WAS OMITTED AND FOR WHICH CONFIDENTIAL TREATMENT WAS REQUESTED. ALL SUCH OMITTED MATERIAL WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

 Schedule 3 

Press Release 
 Syndax
Announces Expansion of Immuno-Oncology Collaboration Evaluating Entinostat in Combination with KEYTRUDA® (pembrolizumab) for the Treatment of Colorectal Cancer 

Encore 601 cohort to begin enrolling patients with microsatellite stable colorectal cancer 

WALTHAM, Mass., April [XX], 2017 – Syndax Pharmaceuticals, Inc. (NASDAQ:SNDX), today announced the expansion of ENCORE 601/KEYNOTE 142, the ongoing
Phase 2 clinical collaboration with a subsidiary of Merck, known as MSD outside the United States and Canada, to include a cohort of patients with microsatellite stable colorectal cancer. This trial is designed to evaluate the safety, tolerability
and efficacy of Syndax’s entinostat, an oral, small molecule that targets immune regulatory cells, in combination with KEYTRUDA® (pembrolizumab), Merck’s anti-PD-1 (programmed death receptor-1) therapy. 

“Microsatellite stable colorectal cancers comprise approximately 85% of colorectal cancers, have limited treatment options once the disease
advances, and have been unresponsive to anti-PD-1 monotherapy,” said Briggs W. Morrison, M.D., Chief Executive Officer of Syndax. “This expansion of ENCORE
601/KEYNOTE 142 is based in part on the previously communicated clinical responses we observed for the entinostat-KEYTRUDA combination in advanced melanoma patients that had progressed on prior anti-PD-1 therapy.” 
 ENCORE 601 continues to evaluate the combination of entinostat and KEYTRUDA in patients
with advanced melanoma or non-small cell lung cancer (NSCLC) who have experienced disease progression following treatment with an
anti-PD-1 therapy, and patients with NSCLC who are naïve to treatment with a PD-1 or
PD-L1 antagonist. In March 2017, Syndax announced that the melanoma cohort achieved the pre-specified criteria required to advance to the second stage of the trial, and re-opened enrollment of that cohort. The Company will present results from the first stage of the melanoma cohort at the upcoming American Society of Clinical Oncology Annual Meeting in June. A decision on whether
the two NSCLC cohorts can proceed to the second stage of the trial is expected in 2Q17. 
 Financial and other terms of the initial agreement, as well as
the amendment covering the expanded collaboration between Syndax and Merck, were not disclosed. 

  

					
	

	 		 	

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WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED. 

 About Syndax Pharmaceuticals, Inc. 

Syndax is a clinical stage biopharmaceutical company developing an innovative pipeline of cancer therapies. Our lead product candidate, entinostat, which was
granted Breakthrough Therapy designation by the FDA following positive results from our Phase 2b clinical trial, ENCORE 301, is currently being evaluated in a Phase 3 clinical trial for advanced hormone receptor positive, human epidermal growth
factor receptor 2 negative breast cancer. Given its potential ability to block the function of immune suppressive cells in the tumor microenvironment, entinostat is also being evaluated in combination with approved
PD-1 antagonists. Ongoing Phase 1b/2 clinical trials combine entinostat with KEYTRUDA from Merck & Co., Inc. for non-small cell lung cancer and melanoma; with
TECENTRIQ from Genentech, Inc. for TNBC; and with BAVENCIO from Pfizer Inc. and Merck KGaA, Darmstadt, Germany, for ovarian cancer. Our second product candidate, SNDX-6352, is a monoclonal antibody that blocks the
CSF-1 receptor and may also block the function of immune suppressive cells in the tumor microenvironment. SNDX-6352 is being evaluated in a single ascending dose Phase 1 clinical trial and is expected to be
developed to treat a variety of cancers. 
 Syndax’s Cautionary Note on Forward-Looking Statements 

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as
“may,” “will,” “expect,” “plan,” “anticipate,” “estimate,” “intend,” “believe” and similar expressions (as well as other words or expressions referencing future events,
conditions or circumstances) are intended to identify forward-looking statements. These forward-looking statements are based on Syndax’s expectations and assumptions as of the date of this press release. Each of these forward-looking statements
involves risks and uncertainties. Actual results may differ materially from these forward-looking statements. Forward-looking statements contained in this press release include, but are not limited to, statements about the progress, timing, clinical
development and scope of clinical trials and the reporting of clinical data for Syndax’s product candidates, and the potential use of our product candidates to treat various cancer indications. Many factors may cause differences between current
expectations and actual results including unexpected safety or efficacy data observed during preclinical or clinical studies, clinical trial site activation or enrollment rates that are lower than expected, changes in expected or existing
competition, changes in the regulatory environment, failure of Syndax’s collaborators to support or advance collaborations or product candidates and unexpected litigation or other disputes. Other factors that may cause Syndax’s actual
results to differ from those expressed or implied in the forward-looking statements in this press release are discussed in Syndax’s filings with the U.S. Securities and Exchange Commission, including the “Risk Factors” sections
contained therein. Except as required by law, Syndax assumes no obligation to update any forward-looking statements contained herein to reflect any change in expectations, even as new information becomes available. 

KEYTRUDA® is a registered trademark of Merck Sharp & Dohme Corp., a subsidiary of
Merck & Co., Inc. 

  

					
	

	 		 	

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WAS FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION PURSUANT TO RULE 24B-2 PROMULGATED UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED.

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