Document:

EX-4.2

 EXHIBIT 4.2 

AEGLEA BIOTHERAPEUTICS, INC. 

AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT 

March 10, 2015 

 TABLE OF CONTENTS 

 

							
	 	    	 	  	Page	 
	 Section 1. DEFINITIONS
	  	 	2	  
			
	 1.1.
	    	Definitions	  	 	2	  
		
	 Section 2. RESTRICTIONS ON TRANSFER
	  	 	2	  
			
	 2.1.
	    	Restrictive Legend	  	 	2	  
			
	 2.2.
	    	Notice of Proposed Transfers	  	 	3	  
		
	 Section 3. REGISTRATION RIGHTS
	  	 	4	  
			
	 3.1.
	    	Certain Definitions	  	 	4	  
			
	 3.2.
	    	Demand Registration.	  	 	5	  
			
	 3.3.
	    	Piggyback Registration.	  	 	6	  
			
	 3.4.
	    	Expenses of Registration	  	 	8	  
			
	 3.5.
	    	Obligations of the Company	  	 	8	  
			
	 3.6.
	    	Indemnification.	  	 	10	  
			
	 3.7.
	    	Information by Holder	  	 	12	  
			
	 3.8.
	    	Transfer and Assignment of Rights	  	 	12	  
			
	 3.9.
	    	Form S-3	  	 	13	  
			
	 3.10.
	    	Delay of Registration	  	 	13	  
			
	 3.11.
	    	Limitations on Subsequent Registration Rights	  	 	13	  
			
	 3.12.
	    	Rule 144 Reporting	  	 	14	  
			
	 3.13.
	    	“Market Stand-Off’ Agreement	  	 	14	  
			
	 3.14.
	    	Termination of Rights	  	 	15	  
		
	 Section 4. RIGHTS OF FIRST REFUSAL
	  	 	15	  
			
	 4.1.
	    	Certain Definitions.	  	 	15	  
			
	 4.2.
	    	Right of First Refusal	  	 	16	  

  
 i 

 TABLE OF CONTENTS 

(CONTINUED) 
  

							
	 	    	 	  	Page	 
	 4.3.
	    	Required Notices	  	 	16	  
			
	 4.4.
	    	Company’s Right to Sell	  	 	16	  
			
	 4.5.
	    	Expiration of Right	  	 	16	  
		
	 Section 5. COMPANY COVENANTS
	  	 	16	  
			
	 5.1.
	    	Affirmative Covenants.	  	 	16	  
			
	 5.2.
	    	Negative Covenants	  	 	21	  
			
	 5.3.
	    	FCPA	  	 	22	  
			
	 5.4.
	    	Right to Conduct Activities	  	 	22	  
			
	 5.5.
	    	Expiration of Covenants	  	 	22	  
		
	 Section 6. MISCELLANEOUS
	  	 	23	  
			
	 6.1.
	    	Additional Investors	  	 	23	  
			
	 6.2.
	    	Governing Law	  	 	23	  
			
	 6.3.
	    	Successors and Assigns	  	 	23	  
			
	 6.4.
	    	Entire Agreement	  	 	23	  
			
	 6.5.
	    	Severability	  	 	23	  
			
	 6.6.
	    	Amendment and Waiver	  	 	24	  
			
	 6.7.
	    	Delays or Omissions	  	 	24	  
			
	 6.8.
	    	Notices, etc	  	 	24	  
			
	 6.9.
	    	Titles and Subtitles	  	 	25	  
			
	 6.10.
	    	Counterparts, Facsimile Signatures	  	 	25	  

  
 ii 

 AEGLEA BIOTHERPEUTICS, INC. 

AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT 

This Amended and Restated Investor Rights Agreement (the “Agreement”) is entered into as of this 10th
day of March 2015, by and among Aeglea BioTherapeutics, Inc., a Delaware corporation (the “Company”), and each holder of the Company’s Series A Preferred Stock, $0.0001 par value per share (“Series A
Preferred Stock”) and Series B Preferred Stock, $0.0001 par value per share (“Series B Preferred Stock”, referred to herein collectively with the Series A Preferred Stock as the “Preferred
Stock”) listed on Schedule A (together with any subsequent investors, or transferees, who become parties hereto as “Investors” pursuant to Section 6.1 below, the “Investors”).

 RECITALS 

WHEREAS, immediately prior to entering into this Agreement, and as a condition to the closing of the transactions contemplated by the Purchase
Agreement (as defined below), Aeglea BioTherapeutics Holdings, LLC, a Delaware limited liability company and predecessor in interest of the Company (the “LLC Predecessor”), has converted from a Delaware limited liability
company to a Delaware “C” corporation (the “Conversion”) in accordance with Section 265 of the General Corporation Law of the State of Delaware and pursuant to a Plan of Conversion adopted by the LLC
Predecessor and its members dated on or about the date hereof (the “Plan”); 
 WHEREAS, in connection with and as a
result of the Conversion, the membership interests held by members of the LLC Predecessor converted into shares of the Company’s capital stock, including shares of the Company’s Common Stock, par value $0.0001 per share (the
“Common Stock”), and shares of the Series A Preferred Stock, as more specifically set forth in the Plan, and the members of the LLC Predecessor became stockholders of the Company; 

WHEREAS, certain of the Investors (the “Existing Investors”) were granted certain rights under an Investor Rights
Agreement dated December 24, 2013, by and among the LLC Predecessor and the Investors (the “Prior Agreement”); 

WHEREAS, the Company and certain of the Investors are parties to the Series B Preferred Stock Purchase Agreement of even date herewith (the
“Purchase Agreement”) providing for the sale and purchase of shares of the Series B Preferred Stock; 
 WHEREAS, in
order to induce the Company to enter into the Purchase Agreement and to induce certain Investors to invest funds in the Company pursuant to the Purchase Agreement, the Company as the successor corporation to the LLC Predecessor and the Investors
desire to enter into this Agreement in order to amend, restate and replace their rights and obligations under the Prior Agreement with the rights and obligations set forth in this Agreement. 

 AGREEMENT 

NOW, THEREFORE, in consideration of the mutual agreements, covenants and conditions contained herein, the Company and the Investors party
hereto agree to amend and restate the Prior Agreement in its entirety and to agree as follows. 
 Section 1. 

DEFINITIONS 
 1.1.
Definitions. Capitalized terms used and not otherwise defined herein shall have the meaning specified in the Certificate of Incorporation of the Company (the “Certificate of Incorporation”). 

Section 2. 
 RESTRICTIONS
ON TRANSFER 
 2.1. Restrictive Legend. Each certificate representing (a) the shares of Preferred Stock, (b) shares of
Common Stock issued upon conversion of the Preferred Stock, and (c) any other securities issued in respect of the Preferred Stock or Common Stock issued upon conversion of the Preferred Stock upon any share split, share dividend,
recapitalization, merger, consolidation or similar event, shall (unless otherwise permitted by the provisions of Section 2.2 below) be stamped or otherwise imprinted with a legend in substantially the following form (in addition to any legend
required under applicable state securities laws). 
 THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO DISTRIBUTION OR RESALE, AND MAY NOT BE SOLD, MORTGAGED, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED
WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND ANY APPLICABLE STATE SECURITIES LAWS, OR THE AVAILABILITY OF AN EXEMPTION FROM THE REGISTRATION PROVISIONS OF THE SECURITIES ACT OF
1933, AS AMENDED, AND APPLICABLE STATE SECURITIES LAWS. COPIES OF THEINVESTOR RIGHTS AGREEMENT, AS MAY BE AMENDED FROM TIME TO TIME, PROVIDING FOR RESTRICTIONS ON TRANSFER OF THESE SECURITIES MAY BE OBTAINED UPON WRITTEN REQUEST BY THE HOLDER OF
RECORD OF THIS CERTIFICATE TO THE SECRETARY OF THE COMPANY AT THE PRINCIPAL EXECUTIVE OFFICES OF THE COMPANY. 
 Each Investor consents to
the Company’s making a notation on its records and giving instructions to any transfer agent of the Preferred Stock or the Common Stock issued upon conversion of the Preferred Stock in order to implement the restrictions on transfer established
in 

  
 2 

 
this Section 2. Such legend shall be removed by the Company from any certificate at such time as the holder of the shares represented by the certificate satisfies the requirements of Rule
144(b)(1) under the Securities Act of 1933, as amended (the “Securities Act”), provided that Rule 144(b)(1) as then in effect does not differ substantially from Rule 144(b)(1) as in effect as of the date of this Agreement,
and provided further that the Company has received from the Holder a written representation that (a) such Investor is not an affiliate of the Company and has not been an affiliate during the preceding three months, (b) such Investor has
beneficially owned the shares represented by the certificate for a period of at least one year, (c) such Investor otherwise satisfies the requirements of Rule 144(b)(1) as then in effect with respect to such shares, and (d) such Investor
will submit the certificate for any such shares to the Company for reapplication of the legend at such time as the holder becomes an affiliate of the Company or otherwise ceases to satisfy the requirements of Rule 144(b)(1) as then in effect.
Notwithstanding anything to the contrary contained herein, for purposes of the foregoing sentence, the term “affiliate” means an “affiliate” as such term is defined under Rule 144. 

2.2. Notice of Proposed Transfers. The holder of each certificate representing Preferred Stock or Common Stock issued upon conversion
of the Preferred Stock by acceptance thereof agrees to comply in all respects with the provisions of this Section 2.2. Prior to any proposed sale, assignment, transfer or pledge of any Preferred Stock or the Common Stock issued upon conversion
of the Preferred Stock, unless there is in effect a registration statement under the Securities Act covering the proposed transfer, the holder thereof shall give written notice to the Company of such holder’s intention to effect such transfer,
sale, assignment or pledge. Each such notice shall describe the manner and circumstances of the proposed transfer, sale, assignment or pledge in sufficient detail, and shall be accompanied at such holder’s expense by a written opinion of legal
counsel who shall, and whose legal opinion shall, be reasonably satisfactory to the Company addressed to the Company, to the effect that the proposed transfer of the Preferred Stock or the Common Stock issued upon conversion of the Preferred Stock
may be effected without registration under the Securities Act. Each certificate evidencing the Preferred Stock or the Common Stock issued upon conversion of the Preferred Stock transferred as above provided shall bear, except if such transfer is
made pursuant to Rule 144, the appropriate restrictive legend set forth in Section 2.1 above, except that such certificate shall not bear such restrictive legend if in the opinion of counsel for such holder and the Company such legend is not
required in order to establish compliance with any provisions of the Securities Act. Notwithstanding the foregoing, no such opinion of counsel shall be necessary for a transfer by a Holder (as defined in Section 3.1(c) below) to an Affiliate of
such Holder, provided that in each case the transferee will be subject to the terms of this Agreement to the same extent as if such transferee were an original Holder hereunder. For purposes of this Agreement, an individual, firm,
corporation, partnership, association, limited liability company, trust or any other entity (collectively, a “Person”) shall be deemed an “Affiliate” of another Person who, directly or indirectly,
controls, is controlled by or is under common control with such Person, including, without limitation, any current or former limited partner, general partner, managing member, manager, officer or director of such Person or any venture capital fund
now or hereafter existing that is controlled by one or more general partners or managing members of, or shares the same management company with, such Person. 

  
 3 

 Section 3. 

REGISTRATION RIGHTS 
 The
Company hereby grants to each of the Holders (as defined below) the registration rights set forth in this Section 3 with respect to the Registrable Securities (as defined below) owned by such Holders. The Company and the Holders agree that the
registration rights provided herein set forth the sole and entire agreement between the Company and the Holders with respect to registration rights for the Company’s securities. 

3.1. Certain Definitions. As used in this Section 3, the following terms shall have the following meanings. 

(a) “Capital Stock” means (a) shares of Common Stock and Preferred Stock (whether now outstanding or hereafter
issued in any context), (b) shares of Common Stock issued or issuable upon conversion of Preferred Stock, and (c) shares of Common Stock issued or issuable upon exercise or conversion, as applicable, of stock options, warrants or other
convertible securities of the Company. 
 (b) The terms “register”, “registered” and
“registration” refer to a registration effected by filing with the Securities and Exchange Commission (the “SEC’) a registration statement (the “Registration Statement”) in
compliance with the Securities Act, and the declaration or ordering by the SEC of the effectiveness of such Registration Statement. 
 (c)
The term “Registrable Securities” means (i) Common Stock issued or issuable upon conversion of the Preferred Stock held (or issuable upon the conversion or exercise of any warrant, right or other security) by Investors
or any transferee as permitted by Section 3.8 hereof, (ii) shares of Common Stock otherwise owned or held by Major Holders (as defined below) as of the date hereof, and (iii) any Common Stock issued as (or issuable upon the conversion
or exercise of any warrant, right or other security that is issued as) a dividend or other distribution with respect to, or in exchange or in replacement of, such above-described securities; provided, however, that Common Stock or
other securities shall only be treated as Registrable Securities if and so long as (A) they have not been sold to or through a broker or dealer or underwriter in a public distribution or a public securities transaction, (B) they have not
been sold in a transaction exempt from the registration and prospectus delivery requirements of the Securities Act under Section 4(a)(1) thereof so that all transfer restrictions and restrictive legends with respect thereto are removed upon the
consummation of such sale, and (C) the registration rights associated with such securities have not been terminated pursuant to Section 3.14 hereof. 

(d) The term “Holder” (collectively, “Holders”) means each Investor and any transferee, as
permitted by Section 3.8 hereof, holding Registrable Securities, securities exercisable for or convertible into Registrable Securities or securities exercisable for securities convertible into Registrable Securities. 

(e) The term “Major Holder” (collectively, “Major Holders”) means each Investor and any
transferee, as permitted by Section 3.8 hereof, holding at least 1,000,000 shares of Registrable Securities (as adjusted for splits, dividends, recapitalizations, combinations and other similar events). 

  
 4 

 (f) The term “Initiating Holders” means the Holders holding at least 62%
of the shares of Series B Preferred Stock then outstanding at the time of any request for registration made pursuant to Section 3.2 of this Agreement. 

3.2. Demand Registration. 

(a) Demand for Registration. If the Company shall receive from Initiating Holders a written demand that the Company effect any
registration (a “Demand Registration”) of at least a majority of the Registrable Securities held by such Initiating Holders then outstanding (other than a registration on Form S-3 or any related form of registration
statement, such a request being provided for under Section 3.9 hereof), the Company will: 
 (i) promptly (but in any event within 10
days) give written notice of the proposed registration to all other Holders; and 
 (ii) use its best efforts to effect such registration as
soon as practicable and as will permit or facilitate the sale and distribution of all or such portion of such Initiating Holders’ Registrable Securities as are specified in such demand, together with all or such portion of the Registrable
Securities of any Holder or Holders joining in such demand as are specified in a written demand received by the Company within 15 days after such written notice is given, provided that the Company shall not be obligated to take any
action to effect any such registration pursuant to this Section 3.2: 
 (A) in any particular jurisdiction in which the
Company would be required to execute a general consent to service of process in effecting such registration, qualification or compliance unless the Company is already subject to service in such jurisdiction and except as may be required by the
Securities Act; 
 (B) after the Company has effected two (2) such registrations pursuant to this Section 3.2, and
the sales of the shares of Common Stock under such registration have closed; 
 (C) if the Company shall furnish to such
Holders a certificate signed by the President of the Company, stating that in the good faith judgment of the Company’s Board of Directors (the “Board”) it would be seriously detrimental to the Company and its
stockholders for such Registration Statement to be filed at the date filing would be required, in which case the Company shall have an additional period or periods of not more than 90 days within which to file such Registration Statement;
provided, however, that the Company shall not use this right to delay the filing for more than 90 days in the aggregate in any 12-month period; or 

(D) prior to the earlier of (1) March 10, 2019, or (2) the date six (6) months after the effective date of
the initial public offering of the Company’s securities. 

  
 5 

 (b) Underwriting. If reasonably required to maintain an orderly market in the Common
Stock, the Holders shall distribute the Registrable Securities covered by their demand by means of an underwriting. If the Initiating Holders intend to distribute the Registrable Securities covered by their demand by means of an underwriting, they
shall so advise the Company as part of their demand made pursuant to this Section 3.2, including the identity of the managing underwriter as determined by the holders of at least 62% of the shares of Registrable Securities held by such
Initiating Holders, and the Company shall include such information in the written notice referred to in Section 3.2(a)(i). In such event, the right of any Holder to registration pursuant to this Section 3.2 shall be conditioned upon such
Holder’s participation in such underwriting and the inclusion of such Holder’s Registrable Securities in the underwriting to the extent provided herein. 

The Company shall, together with all Holders of shares proposing to distribute their securities through such underwriting, enter into an
underwriting agreement in customary form with the underwriter or underwriters selected by the Initiating Holders holding at least 62% of the shares of Preferred Stock held by Initiating Holders and reasonably satisfactory to the Company.
Notwithstanding any other provision of this Section 3.2, if the underwriter shall advise the Company that marketing factors (including, without limitation, an adverse effect on the per share offering price) require a limitation of the number of
shares to be underwritten, then the Company shall so advise all Holders of Registrable Securities that have requested to participate in such offering, and the number of shares of Registrable Securities that may be included in the registration and
underwriting shall be allocated pro rata among such Holders thereof in proportion, as nearly as practicable, to the amounts of Registrable Securities held by such Holders at the time of filing the Registration Statement. No Registrable Securities
excluded from the underwriting by reason of the underwriter’s marketing limitation shall be included in such registration. 
 If any
Holder disapproves of the terms of the underwriting, such Holder may elect to withdraw therefrom by written notice to the Company, the underwriter and the Initiating Holders. The Registrable Securities so withdrawn shall also be withdrawn from
registration. 
 If the underwriter has not limited the number of Registrable Securities to be underwritten, the Company may include
securities for its own account (or for the account of other stockholders) in such registration if the underwriter so agrees and if the number of Registrable Securities would not thereby be limited. 

3.3. Piggyback Registration. 

(a) Company Registration. If at any time or from time to time the Company shall determine to register any of its securities, either for
its own account or for the account of security holders, other than a registration relating solely to employee benefit plans, a registration on Form S-4 relating solely to an SEC Rule 145 transaction or a registration pursuant to Section 3.2 or
3.9 hereof, the Company will: 
 (i) promptly (but in any event within 10 days) give to each Holder written notice thereof; and 

  
 6 

 (ii) include in such registration (and any related qualification under state securities laws or
other compliance), and in any underwriting involved therein, all the Registrable Securities specified in a written request or requests, made within 15 days after receipt of such written notice from the Company, by any Holder or Holders, except as
set forth in Section 3.3(b) below. 
 Such Registrable Securities shall only be included to the extent that inclusion will not diminish
the number of securities included by the Company. 
 (b) Underwriting. If the registration of which the Company gives notice is for a
registered public offering involving an underwriting, the Company shall so advise the Holders as a part of the written notice given pursuant to Section 3.3(a)(i). In such event the right of any Holder to registration pursuant to this
Section 3.3 shall be conditioned upon such Holder’s participation in such underwriting and the inclusion of such Holder’s Registrable Securities in the underwriting to the extent provided herein. 

All Holders proposing to distribute their Registrable Securities through such underwriting shall, together with the Company and the other
parties distributing their securities through such underwriting, enter into an underwriting agreement in customary form with the underwriter or underwriters selected for such underwriting by the Company. Notwithstanding any other provision of this
Section 3.3, if the underwriter determines that marketing factors require a limitation of the number of shares to be underwritten, the underwriter may limit the number of Registrable Securities to be included in the registration and
underwriting, or may exclude Registrable Securities entirely from such registration and underwriting subject to the terms of this Section 3.3. The Company shall so advise all holders of the Company’s securities that would otherwise be
registered and underwritten pursuant hereto, and the number of shares of such securities, including Registrable Securities, that may be included in the registration and underwriting shall be allocated in the following manner: (i) first, shares,
other than Registrable Securities and other securities that have contractual rights with respect to registration similar to those provided for in this Section 3.3, requested to be included in such registration by stockholders shall be excluded,
and (ii) second, if a limitation on the number of shares still is required, securities other than Registrable Securities that have contractual rights with respect to registration shall be excluded, and (iii) third, if a limitation on the
number of shares is still required, the number of Registrable Securities that may be included shall be allocated among the Holders thereof in proportion, as nearly as practicable, to the amounts of Registrable Securities held by each such Holder at
the time of filing the Registration Statement; provided, however, that the aggregate value of securities (including Registrable Securities) to be included in such registration by the Holders may not be so reduced to less than 25% of
the total value of all securities included in such registration except in the Company’s IPO (as defined below). For purposes of any such underwriter cutback, all Registrable Securities and other securities held by any holder that is a
partnership, limited liability company or corporation shall also include any Registrable Securities held by the partners, retired partners, members, stockholders or affiliated entities of such holder, or the estates and family members of any such
partners, retired partners, members and any trusts for the benefit of any of the foregoing Persons, and such holder and other Persons shall be deemed to be a single “selling holder,” and any pro rata reduction with respect to such
“selling holder” shall be based upon the aggregate amount of shares carrying registration rights owned by all entities and individuals included in such “selling holder,” as 

  
 7 

 
defined in this sentence. No securities excluded from the underwriting by reason of the underwriter’s marketing limitation shall be included in such registration. Except as specifically set
forth herein, nothing in this Section 3.3(b) is intended to diminish the number of securities to be included by the Company in the underwriting. 

If any Holder disapproves of the terms of the underwriting, it may elect to withdraw therefrom by written notice to the Company and the
underwriter. The Registrable Securities so withdrawn shall also be withdrawn from registration. 
 (c) Right to Terminate
Registration. The Company shall have the right to terminate or withdraw any registration initiated by it under this Section 3.3 prior to the effectiveness of such registration whether or not any Holder has elected to include securities in
such registration. 
 3.4. Expenses of Registration. All expenses incurred in connection with all registrations effected pursuant to
Sections 3.2, 3.3 and 3.9, including without limitation all registration, filing and qualification fees (including state securities law fees and expenses), printing expenses, escrow fees, fees and disbursements of counsel for the Company (and if
(a) the participating Holders request representation by a separate special counsel for the participating Holders, the reasonable fees and disbursements of one such counsel, not to exceed $50,000, or, (b) in the case of any public offering
or the IPO, the Major Holders request representation by a separate special counsel for the participating Major Holders, the reasonable fees and disbursements of one such counsel, not to exceed $100,000) expenses of any special audits incidental to
or required by such registration shall be borne by the Company; provided, however, that the Company shall not be required to pay share transfer taxes or underwriters’ discounts or selling commissions relating to Registrable
Securities; and provided, further, that the Company shall not be required to pay for any expenses of any registration pursuant to Section 3.9 if the Company has effected two (2) registrations pursuant to Section 3.9 in the
preceding twelve (12) months and paid the expenses thereof, in which event the Holders of Registrable Securities to be registered shall bear all such expenses pro rata on the basis of Registrable Securities to be registered. Notwithstanding
anything to the contrary above, the Company shall not be required to pay for any expenses of any registration proceeding under Section 3.2 if the registration request is subsequently withdrawn at the request of the Holders of the Registrable
Securities to have been registered, in which event the Holders of Registrable Securities to have been registered shall bear all such expenses pro rata on the basis of the Registrable Securities to have been registered. Notwithstanding the preceding
sentence, however, if at the time of the withdrawal, the Holders have learned of a materially adverse change in the condition, business or prospects of the Company from that known to the Holders at the time of their request, then the Holders shall
not be required to pay any of said expenses and shall retain their rights pursuant to Section 3.2. 
 3.5. Obligations of the
Company. Whenever required under this Section 3 to effect the registration of any Registrable Securities, the Company shall, as expeditiously as reasonably possible: 

(a) prepare and file with the SEC a Registration Statement with respect to such Registrable Securities and use its diligent efforts to cause
such Registration Statement to become effective, and keep such Registration Statement effective for the lesser of 90 days or until the Holder or Holders have completed the distribution relating thereto; 

  
 8 

 (b) prepare and file with the SEC such amendments and supplements to such Registration Statement
and the prospectus used in connection with such Registration Statement as may be necessary to keep such Registration Statement effective and to comply with the provisions of the Securities Act with respect to the disposition of all securities
covered by such Registration Statement for the period set forth in paragraph (a) above; 
 (c) furnish to the Holders such numbers of
copies of a prospectus, including a preliminary prospectus, in conformity with the requirements of the Securities Act, and such other documents as they may reasonably request in order to facilitate the disposition of Registrable Securities owned by
them; 
 (d) use its reasonable efforts to register or otherwise qualify the securities covered by such Registration Statement under such
other securities laws of such states and other jurisdictions as shall be reasonably requested by the Holders or the managing underwriter, provided that the Company shall not be required in connection therewith or as a condition thereto
to qualify to do business or to file a general consent to service of process in any such states or jurisdictions; 
 (e) in the event of any
underwritten public offering, enter into and perform its obligations under an underwriting agreement, in usual and customary form, with the managing underwriter of such offering. Each Holder participating in such underwriting shall also enter into
and perform its obligations under such an agreement; 
 (f) notify each Holder of Registrable Securities covered by such Registration
Statement, at any time when a prospectus relating thereto is required to be delivered under the Securities Act, of the happening of any event as a result of which the prospectus included in such Registration Statement, as then in effect, includes an
untrue statement of a material fact or omits to state a material fact required to be stated therein or necessary to make the statements therein not misleading in light of the circumstances then existing; 

(g) use its reasonable efforts to list the Registrable Securities covered by such Registration Statement with any securities exchange on which
the Capital Stock of the Company are then listed; 
 (h) make available for inspection by each Holder including Registrable Securities in
such registration, any underwriter participating in any distribution pursuant to such registration, and any attorney, accountant or other agent retained by such Holder or underwriter, all financial and other records, pertinent corporate documents
and properties of the Company, as such parties may reasonably request, and cause the Company’s officers, directors and employees to supply all information reasonably requested by any such Holder, underwriter, attorney, accountant or agent in
connection with such Registration Statement; 
 (i) cooperate with Holders including Registrable Securities in such registration and the
managing underwriters, if any, to facilitate the timely preparation and delivery of certificates representing Registrable Securities to be sold, such certificates to be in such denominations and registered in such names as such Holders or the
managing underwriters may request at least two (2) business days prior to any sale of Registrable Securities; and 

  
 9 

 (j) permit any Holder which Holder, in the sole and exclusive judgment, exercised in good faith,
of such Holder, might be deemed to be a controlling Person of the Company, to participate in good faith in the preparation of such Registration Statement and to require the insertion therein of material, furnished to the Company in writing, that in
the reasonable judgment of such Holder and its counsel should be included. 
 3.6. Indemnification. 

(a) The Company will, and does hereby undertake to, indemnify and hold harmless each Holder of Registrable Securities, each of such
Holder’s officers, directors, managers, partners, members and agents, and each Person controlling such Holder, with respect to any registration, qualification or compliance effected pursuant to this Section 3, and each underwriter, if any,
and each Person who controls any underwriter, of the Registrable Securities held by or issuable to such Holder, against all claims, losses, damages and liabilities (or actions in respect thereto) to which they may become subject under the Securities
Act, the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or other federal or state law arising out of or based on (i) any untrue statement (or alleged untrue statement) of a material fact contained in
any prospectus, offering circular or other similar document (including any related Registration Statement, notification, or the like) incident to any such registration, qualification or compliance, or based on any omission (or alleged omission) to
state therein a material fact required to be stated therein or necessary to make the statements therein not misleading in light of the circumstances in which they were made, (ii) any violation or alleged violation by the Company of any federal,
state or common law rule or regulation applicable to the Company in connection with any such registration, qualification or compliance, or (iii) any failure to register or qualify Registrable Securities in any state where the Company or its
agents have affirmatively undertaken or agreed in writing that the Company (the undertaking of any underwriter chosen by the Company being attributed to the Company) will undertake such registration or qualification on behalf of the Holders of such
Registrable Securities (provided that in such instance the Company shall not be so liable if it has undertaken its best efforts to so register or qualify such Registrable Securities) and will reimburse, as incurred, each such Holder, each such
underwriter and each such director, manager, officer, partner, member agent and controlling Person, for any legal and any other expenses reasonably incurred in connection with investigating or defending any such claim, loss, damage, liability or
action; provided that the Company will not be liable in any such case to the extent that any such claim, loss, damage, liability or expense arises out of or is based on any untrue statement or omission made in conformity with written information
furnished to the Company by an instrument duly executed by such Holder or underwriter and stated to be specifically for use therein. 
 (b)
Each Holder will, and if Registrable Securities held by or issuable to such Holder are included in such registration, qualification or compliance pursuant to this Section 3, does hereby undertake to indemnify and hold harmless the Company, each
of its directors and officers, and each Person controlling the Company, each underwriter, if any, and each Person who controls any underwriter, of the Company’s securities covered by such a Registration Statement, and each other Holder, each of
such other Holder’s officers, directors, managers, 

  
 10 

 
partners, members and agents and each Person controlling such other Holder, against all claims, losses, damages and liabilities (or actions in respect thereof) arising out of or based on any
untrue statement (or alleged untrue statement) of a material fact contained in any such Registration Statement, prospectus, offering circular or other document, or any omission (or alleged omission) to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading in light of the circumstances in which they were made; and will reimburse, as incurred, the Company, each such underwriter, each such other Holder, and each such director,
officer, manager, partner, member and controlling Person of the foregoing, for any legal or any other expenses reasonably incurred in connection with investigating or defending any such claim, loss, damage, liability or action, in each case to the
extent, but only to the extent, that such untrue statement (or alleged untrue statement) or omission (or alleged omission) was made in such Registration Statement, prospectus, offering circular or other document, in reliance upon and in conformity
with written information furnished to the Company by an instrument duly executed by such Holder and stated to be specifically for use therein; provided, however, that the liability of each Holder hereunder (unless such Holder’s
liability hereunder is based upon such Holder’s willful misconduct as determined by the nonappealable final decision of a court) shall be limited to the proportion of any such claim, loss, damage or liability that is equal to the proportion
that the public offering price of the shares sold by such Holder under such Registration Statement bears to the total public offering price of all securities sold thereunder, but in any event not to exceed the net proceeds received by such Holder
from the sale of securities under such Registration Statement. It is understood and agreed that the indemnification obligations of each Holder pursuant to any underwriting agreement entered into in connection with any Registration Statement shall be
limited to the obligations contained in this subsection 3.6(b). 
 (c) Each party entitled to indemnification under this Section 3.6
(the “Indemnified Party”) shall give notice to the party required to provide such indemnification (the “Indemnifying Party”) of any claim as to which indemnification may be sought promptly after such
Indemnified Party has actual knowledge thereof, and shall permit the Indemnifying Party to assume the defense of any such claim or any litigation resulting therefrom; provided that counsel for the Indemnifying Party, who shall conduct the defense of
such claim or litigation, shall be subject to approval by the Indemnified Party (whose approval shall not be unreasonably withheld) and the Indemnified Party may participate in such defense at the Indemnifying Party’s expense if representation
of such Indemnified Party would be inappropriate due to actual or potential differing interests between such Indemnified Party and any other party represented by such counsel in such proceeding; and provided further that the failure of any
Indemnified Party to give notice as provided herein shall not relieve the Indemnifying Party of its obligations under this Section 3, except to the extent that such failure to give notice shall materially adversely affect the Indemnifying Party
in the defense of any such claim or any such litigation. An Indemnifying Party, in the defense of any such claim or litigation, may, without the consent of each Indemnified Party, consent to entry of any judgment or enter into any settlement that
includes as an unconditional term thereof the giving by the claimant or plaintiff therein, to such Indemnified Party, of a release from all liability with respect to such claim or litigation. 

(d) In order to provide for just and equitable contribution to joint liability under the Securities Act in any case in which either
(i) any Holder exercising rights under this Agreement, or any controlling Person of any such Holder, makes a claim for indemnification 

  
 11 

 
pursuant to this Section 3.6 but it is judicially determined (by the entry of a final judgment or decree by a court of competent jurisdiction and the expiration of time to appeal or the
denial of the last right of appeal) that such indemnification may not be enforced in such case notwithstanding the fact that this Section 3.6 provides for indemnification in such case, or (ii) contribution under the Securities Act may be
required on the part of any such Holder or any such controlling Person in circumstances for which indemnification is provided under this Section 3.6; then, and in each such case, the Company and such Holder will contribute to the aggregate
claims, losses, damages or liabilities to which they may be subject (after contribution from others) in such proportion so that such Holder is responsible for the portion represented by the percentage that the public offering price of the securities
offered by such Holder pursuant to the Registration Statement bears to the public offering price of all securities offered by such Registration Statement, and the Company will be responsible for the remaining portion (without prejudice as to the
Company’s right to contributions from any other responsible parties); provided, however, that, in any case, (A) no such Holder will be required to contribute any amount in excess of the public offering price of all securities
offered by it pursuant to such Registration Statement, after deduction of underwriting discounts and commissions (unless such Holder’s liability hereunder is based upon such Holder’s willful misconduct as determined by the nonappealable
final decision of a court); and (B) no Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) will be entitled to contribution from any Person who was not guilty of such fraudulent
misrepresentation. 
 (e) Notwithstanding the foregoing, to the extent that the provisions on indemnification and contribution contained in
the underwriting agreement entered into in connection with the underwritten public offering are in conflict with the foregoing provisions, the provisions in the underwriting agreement shall control. 

(f) The indemnities provided in this Section 3.6 shall survive the transfer of any Registrable Securities by such Holder. 

3.7. Information by Holder. The Holder or Holders of Registrable Securities included in any registration shall furnish to the Company
such information regarding such Holder or Holders and the distribution proposed by such Holder or Holders as the Company may reasonably request in writing and as shall be required in connection with any registration, qualification or compliance
referred to in this Section 3. 
 3.8. Transfer and Assignment of Rights. The rights contained in Section 3 hereof may be
assigned or otherwise conveyed to transferees or assignees of Registrable Securities, who shall be considered a “Holder” for purposes hereof, provided that (i) such transfer is effected in compliance with
Section 2.2 hereof, (ii) such transferee (A) is an Affiliate or current or retired principal, manager or officer of the transferor of such Registrable Securities or (B) acquires at least 100,000 shares of the transferor’s
Registrable Securities (as adjusted for splits, dividends, recapitalizations, combinations and other similar events), provided that such transferee is not a Person whom the Company reasonably believes is a competitor of the Company (it
being understood that Affiliates of Lilly Ventures Fund I, LLC (“ LV”) and Novartis Bioventures Ltd (“NBV”) shall not be deemed competitors for purposes of this Agreement), and (iii) such
transferee agrees in writing to be subject to all restrictions set forth in this Agreement. The rights contained in Sections 4 and 5 hereof may be assigned or otherwise conveyed by a party to this 

  
 12 

 
Agreement to transferees or assignees of shares of Preferred Stock or Common Stock issued upon conversion of shares of Preferred Stock, who shall be considered a “Holder” for purposes
hereof, provided that (i) such transfer is effected in compliance with Section 2.2 hereof, (ii) such transferee is an Affiliate or current or retired principal, manager or officer of the transferor of such Registrable
Securities, provided that such transferee is not a Person whom the Company reasonably believes is a competitor of the Company, and (iii) such transferee agrees in writing to be subject to all restrictions set forth in this
Agreement. For the avoidance of doubt, the transfer or assignment of rights pursuant to this Section 3.8 shall not affect the transferor’s rights under this Agreement with respect to the remaining shares of Registrable Securities held by
such transferor, if any. 
 3.9. Form S-3. The Company shall use its best efforts to qualify for registration on Form S-3 (or any
future form that is substantially equivalent to the current Form S-3) as soon as it is eligible. After the Company has qualified for the use of Form S-3, the Holders of at least twenty percent (20%) of the shares constituting the
then-outstanding shares of Preferred Stock on an as-converted to Common Stock basis plus the then-outstanding Common Stock that were issued upon the conversion of shares of Preferred Stock previously held by such Holders shall have the right to
request registrations on Form S-3 thereafter under this Section 3.9. The Company shall give notice to all Holders of Registrable Securities of the receipt of a request for registration pursuant to this Section 3.9 and shall provide a
reasonable opportunity for other Holders to participate in the registration. Subject to the foregoing, the Company will use its diligent efforts to effect as soon as practicable the registration of all shares of Registrable Securities on Form S-3 to the extent requested by the Holder or Holders thereof for purposes of disposition; provided, however, that the Company shall not be obligated to effect any such registration if the Holders,
together with the holders of any other securities of the Company entitled to inclusion in such registration, propose to sell Registrable Securities and such other securities (if any) at an aggregate price to the public of less than $1,000,000.
Notwithstanding the foregoing, nothing herein shall restrict, prohibit or limit in any way a Holder’s ability to exercise its registration rights under Sections 3.2 or 3.3 hereof. The Company shall have no obligation to take any action to
effect any registration pursuant to this Section 3.9 for any of the reasons set forth in Section 3.2(a)(ii)(A) or (C) (which shall be deemed to apply to the obligations under this Section 3.9 with equal force). In addition, any
registration pursuant to this Section 3.9 shall be subject to the provisions of Section 3.2(b), which shall be deemed to apply to the obligations under this Section 3.9 with equal force, except that any reference therein to
Section 3.2 or a subsection thereof shall, for these purposes only, be deemed to be a reference to this Section 3.9. 
 3.10.
Delay of Registration. No Holder shall have any right to obtain or seek an injunction restraining or otherwise delaying any such registration as the result of any controversy that might arise with respect to the interpretation or
implementation of this Section 3. 
 3.11. Limitations on Subsequent Registration Rights. From and after the date of this
Agreement, the Company shall not, without the prior written consent of the Major Holders holding at least 62% of the shares of Series B Preferred Stock then outstanding, enter into any agreement with any holder or prospective holder of any
securities of the Company that would allow such holder or prospective holder to (a) require the Company to effect a registration, or (b) include any securities in any registration filed under Section 3.2, 3.3 or 3.9 hereof, unless,
under 

  
 13 

 
the terms of such agreement, such holder or prospective holder may include such securities in any such registration only to the extent that the inclusion of such securities will not diminish the
amount of Registrable Securities that are included in such registration. 
 3.12. Rule 144 Reporting. With a view to making available
to the Holders the benefits of certain rules and regulations of the SEC that may permit the sale of the Registrable Securities to the public without registration, the Company agrees to use its diligent efforts to: 

(a) make and keep current public information available, within the meaning of SEC Rule 144 or any similar or analogous rule promulgated under
the Securities Act, at all times after it has become subject to the reporting requirements of the Exchange Act; 
 (b) file with the SEC, in
a timely manner, all reports and other documents required of the Company under the Securities Act and Exchange Act (after it has become subject to such reporting requirements); and 

(c) so long as a Holder owns any Registrable Securities, furnish to such Holder forthwith upon request a written statement by the Company as
to its compliance with the reporting requirements of said Rule 144 (at any time commencing 90 days after the effective date of the first registration filed by the Company for an offering of its securities to the general public), the Securities Act
and the Exchange Act (at any time after it has become subject to such reporting requirements); a copy of the most recent annual or quarterly report of the Company; and such other reports and documents as a Holder may reasonably request in availing
itself of any rule or regulation of the SEC allowing it to sell any such securities without registration. 
 3.13. “Market
Stand-Off’ Agreement. Each Holder hereby agrees that during a period, not to exceed 180 days (or, if required by such underwriter, such longer period of time as is necessary to enable such underwriter to issue a research report or make a
public appearance that relates to an earnings release or announcement by the Company within 18 days prior to or after the date that is one hundred eighty (180) days after the effective date of the registration statement relating to such
offering, but in any event not to exceed two hundred ten (210) days following the effective date of the registration statement relating to such offering), following the effective date of the initial, effective registration statement of the
Company filed under the Securities Act (“IPO”), it shall not, to the extent requested by the Company and any underwriter, sell, pledge, transfer, make any short sale of, loan, grant any option for the purchase of, or
otherwise transfer or dispose of any Capital Stock of the Company held by it at any time during such period except Capital Stock included in such registration; provided, however, that all “One Percent Stockholders” and all
officers and directors of the Company enter into similar agreements. The underwriters in connection with the IPO are intended third-party beneficiaries of this Section 3.13 and shall have the right, power and authority to enforce the provisions
hereof as though they were a party hereto. Each Holder further agrees to execute such agreements as may be reasonably requested by the underwriters in the IPO that are consistent with this Section 3.13 or that are necessary to give further
effect thereto. 
 For purposes of this Agreement, the term “One Percent Stockholder” shall mean a
stockholder of the Company who holds at least 1% of the outstanding Capital Stock of the Company (assuming conversion of all outstanding preferred securities of the Company). 

  
 14 

 In order to enforce the foregoing covenant, the Company may impose stop-transfer instructions
with respect to the Capital Stock of each Holder (and the shares or securities of every other Person subject to the foregoing restriction) until the end of such period. 

3.14. Termination of Rights. The rights of any particular Holder under this Section 3 hereof shall terminate as to any Holder on
the earlier of (a) the date that is five (5) years after the closing of a Qualified Public Offering or (b) the date on which such Holder ceases to hold Registrable Securities. 

Section 4. 
 RIGHTS OF
FIRST REFUSAL 
 4.1. Certain Definitions. 

(a) The term “Eligible Holder” shall mean a Holder, as defined in Section 3.1(d). 

(b) The term “New Securities” shall mean any Capital Stock of the Company, whether now authorized or not, and rights,
options or warrants to purchase Capital Stock, and securities of any type whatsoever that are, or may become, convertible into or exercisable for Capital Stock; provided that the term “New Securities” does not
include: (i) 12,901,499 shares or options to purchase such number of shares, or a combination of both, of the Company’s Common Stock (as adjusted for any splits, dividends, combination or other reclassification), previously issued or to be
issued to directors, officers, employees or consultants of the Company pursuant to plans or arrangements approved by the Board; (ii) Common Stock issued upon conversion of the Preferred Stock; (iii) securities issued pursuant to any
dividend on, or split, combination or other reclassification by the Company of, the Preferred Stock; (iv) Common Stock issued in a Qualified Public Offering; (v) Capital Stock, or options, warrants or other securities convertible into or
exercisable for Capital Stock of the Company, issued pursuant to leasing, financing or other lending arrangements approved by the Board, including the affirmative vote or consent of a majority of the Preferred Directors; (vi) Capital Stock, or
options, warrants or other securities convertible into or exercisable for Capital Stock of the Company, issued pursuant to agreements with strategic partners of the Company or its Affiliates approved by the Board, including the affirmative vote or
consent of a majority of the Preferred Directors; (vii) the issuance or sale of up to 821,471 shares of Series B Preferred Stock (as adjusted for share splits, share distributions, combinations and other reclassifications) to KBI Biopharma,
Inc. (“KBI”) pursuant to the KBI MSA and (viii) shares of Series B Preferred Stock issued pursuant to the Purchase Agreement. “KBI MSA” means the Master Service Agreement by and between Aeglea
Development, Inc., a Subsidiary of the Company, and KBI Biopharma, Inc. dated December 24, 2013, as may be amended from time to time. 

(c) The term “Pro Rata Share” of an Eligible Holder means the ratio, (i) the numerator of which is the number of
shares of Common Stock issuable upon conversion of the Preferred Stock held by such Eligible Holder, and the number of shares of Common Stock issued to such Eligible Holder upon the conversion of Preferred Stock previously held by such Eligible
Holder, on the date of the Company’s written notice pursuant to Section 4.3 hereof, and (ii) the 

  
 15 

 
denominator of which is the number of shares of Common Stock of the Company outstanding, assuming for this purpose conversion or exercise of all securities convertible into or exercisable for
Common Stock of the Company (including without limitation the Preferred Stock). 
 4.2. Right of First Refusal. The Company hereby
grants to each Eligible Holder, subject to the terms and conditions specified in this Section 4, the right of first refusal to purchase, on the terms and conditions set forth in the Company’s notice pursuant to Section 4.3 hereof, up
to its Pro Rata Share of all New Securities that the Company may, from time to time, propose to sell and issue. 
 4.3. Required
Notices. In the event the Company proposes to undertake an issuance of New Securities, it shall give each Eligible Holder written notice of its intention, describing the type of New Securities, the price and the general terms upon which the
Company proposes to issue the same. Each Eligible Holder shall have 30 days from the date of any such notice to exercise its right of first refusal under Section 4.2 hereof for the price and upon the general terms specified in the notice by
giving written notice to the Company and stating therein the quantity of New Securities to be purchased. 
 4.4. Company’s Right to
Sell. The Company shall have 60 days after the 30-day period described in Section 4.3 hereof to sell all such New Securities respecting which the Eligible Holders’ rights of first refusal hereunder were not exercised, at a price and
upon terms no more favorable in any material respect to the purchasers thereof than specified in the Company’s notice. In the event the Company has not sold all such New Securities within such 60-day period, the Company shall not thereafter
issue or sell any New Securities without first notifying the Eligible Holders in the manner provided herein. 
 4.5. Expiration of
Right. The rights of first refusal granted under this Section 4 shall not apply to, and shall expire upon, a Qualified Public Offering. 

Section 5. 
 COMPANY
COVENANTS 
 The Company hereby covenants and agrees on behalf of itself and its Subsidiaries to the following. 

5.1. Affirmative Covenants. 

The Company hereby covenants and agrees as follows. 

(a) Financial Statements and Information. The Company will keep books of account and prepare financial statements and will cause to be
furnished to each Investor the following reports (all of the foregoing and following to be kept and prepared in accordance with United States generally accepted accounting principles applied on a consistent basis), provided, however,
that the Company shall not be obligated pursuant to this Section 5.1(a) to provide financial information to (x) any Investor, or its transferee, holding fewer than 2,000,000 shares of Preferred Stock (as adjusted for share splits, share
distributions, combinations and other reclassifications) or (y) any Person whom the Company reasonably believes is a competitor of the Company. 

  
 16 

 (i) As soon as practicable, but in any event within forty-five (45) days after the end of
each fiscal year of the Company, the Company will furnish to each Investor preliminary, unaudited consolidated balance sheets of the Company and its Subsidiaries, if any, as at the end of such fiscal year, and preliminary, unaudited consolidated
statements of income and cash flows of the Company and its Subsidiaries, if any, for such fiscal year, setting forth in each case in comparative form the figures for the previous fiscal year, if any, all in reasonable detail. 

(ii) As soon as practicable, but in any event within one hundred fifty (150) days after the end of each fiscal year of the Company, the
Company will furnish to each Investor (A) audited consolidated balance sheets of the Company and its Subsidiaries, if any, as at the end of such fiscal year, and audited consolidated statements of income and cash flows of the Company and its
Subsidiaries, if any, for such fiscal year, setting forth in each case in comparative form the figures for the previous fiscal year, if any, all in reasonable detail and accompanied by a report and opinion thereon by independent auditors selected by
the Company’s Board, and (B) a copy of such auditors’ management letter prepared in connection therewith, if any, (as soon as such management letter is available, which may be greater than the aforesaid 150-day period). 

(iii) As soon as practicable after the end of each quarter of the fiscal year, but in any event within thirty (30) days after the end of
each such quarter, the Company will furnish to each Investor the unaudited consolidated balance sheets of the Company and its Subsidiaries, if any, as of the end of such quarter, and its unaudited consolidated statements of income and cash flows for
such quarter, setting forth in each case in comparative form the figures for the corresponding period of the preceding fiscal year, all in reasonable detail, and except that such financial statements may not contain notes and will be subject to
year-end adjustment. 
 (iv) As soon as practicable after the end of each month, but in any event within thirty (30) days thereafter,
the Company will furnish to each Investor the unaudited consolidated balance sheet of the Company and its Subsidiaries, if any, as of the end of such month and its unaudited statement of and cash flows for such month, indicating actual results
versus the Company’s plan for such month, setting forth in each case in comparative form the figures for the corresponding period of the preceding fiscal year, except that such financial statements may not contain notes and will be subject to
year-end adjustment. 
 (v) As soon as practicable after the end of each quarter of the fiscal year, but in any event within thirty
(30) days after the end of each such quarter, the Company will furnish to each Investor a report from the Company’s Chief Executive Officer describing the general progress of the Company and its Subsidiaries for such quarter, setting forth
details on research, development, sales, marketing and other operating activities. 
 (vi) As soon as practicable, but in any event not
less than thirty (30) days before the end of each fiscal year, the Company will furnish to each Investor an annual 

  
 17 

 
operating plan and budget for the next fiscal year, and, as soon as practicable after the adoption thereof by the Board before the beginning of such fiscal year, copies of any revisions to such
annual operating plan and budget. 
 (vii) The Company will furnish to each Investor with reasonable promptness, such other information
respecting the business, properties or the condition or operations, financial or other, of the Company or any Subsidiary as such Investor may from time to time reasonably request. 

(b) Inspection. The Company shall permit each Investor and its transferee(s) (provided such transfer is effected in compliance with
Section 2.2 hereof), its attorney or its other representative to visit and inspect the Company’s properties, to examine the Company’s books of account and other records, to make copies or extracts therefrom and to discuss the
Company’s affairs, finances and accounts with its officers, management, employees and independent auditors all at such reasonable times and as often as such Investor or transferee may reasonably request; provided, however, that
the Company shall not be obligated pursuant to this Section 5.1(b) to provide trade secrets or confidential information or to provide information to any Person whom the Company reasonably believes is a competitor of the Company;
provided, further, that such Investor shall bear any costs or expenses of such investigations or inquiries. 
 (c) Payment
of Taxes. The Company shall pay, and cause each Subsidiary to pay, and discharge all taxes, assessments and governmental charges or levies imposed upon it or upon its income, profits or business, or upon any properties belonging to it, prior to
the date on which penalties attach thereto, and all lawful claims that, if unpaid, might become a lien or charge upon any properties of the Company or any Subsidiary, provided that neither the Company nor any Subsidiary shall be
required to pay any such tax, assessment, charge, levy or claim that is being contested in good faith and by appropriate proceedings if the Company or any Subsidiary shall have set aside on its books sufficient reserves, if any, with respect
thereto. 
 (d) Payment of Trade Debt. The Company shall pay, and cause each Subsidiary to pay, when due, or in conformity with
customary trade terms but not later than ninety (90) days from the due date, all lease obligations, all trade debt, and all other indebtedness incident to the operations of the Company or its Subsidiaries, except such as are being contested in
good faith and by proper proceedings if the Company or Subsidiary concerned shall have set aside on its books sufficient reserves, if any, with respect thereto. 

(e) Maintenance of Insurance. The Company shall maintain, and cause each Subsidiary to maintain, insurance with responsible and
reputable insurance companies or associations in such amounts and covering such risks as is customarily carried by companies engaged in similar businesses and owning similar properties in the same general areas in which the Company or such
Subsidiary operates. For so long any Preferred Director (as defined in the Company’s Certificate of Incorporation) is serving on the Board, the Company shall maintain a Directors and Officers liability insurance policy in an amount and on terms
satisfactory to the Board, including a majority of the Preferred Directors. 
 (f) Intellectual Property. The Company shall secure,
preserve and maintain, and cause each Subsidiary to secure, preserve and maintain, all licenses and other rights to use 

  
 18 

 
patents, processes, licenses, permits, trademarks, trade names, inventions, intellectual property rights or copyrights owned or used by it to the extent necessary to the conduct of its business
or the business of any Subsidiary. 
 (g) Compliance with Laws. The Company shall comply, and cause each Subsidiary to comply, with
the requirements of all applicable laws, rules, regulations and orders of any governmental authority, noncompliance with which could materially adversely affect its business or condition, financial or otherwise. 

(h) Records and Books of Account. The Company shall keep, and cause each Subsidiary to keep, adequate records and books of account in
which complete entries will be made in accordance with generally accepted accounting principles consistently applied, reflecting all financial transactions of the Company and any Subsidiary, and in which, for each fiscal year, all proper reserves
for depreciation, depletion, returns of merchandise, obsolescence, amortization, taxes, bad debts and other purposes in connection with its business shall be made. 

(i) Maintenance of Properties. The Company shall maintain and preserve, and cause each Subsidiary to maintain and preserve, all of its
properties and assets necessary for the proper conduct of its business, in good repair, working order and condition, ordinary wear and tear excepted. 

(j) Regulatory Compliance. 

(i) The Company shall comply, and cause each Subsidiary to comply, with all minimum funding requirements applicable to any pension, employee
benefit plans, or employee contribution plans that are subject to the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), or to the Internal Revenue Code of 1986, as amended (the
“Code”), and comply, and cause each Subsidiary to comply, in all other material respects with the provisions of ERISA and the Code, and the rules and regulations thereunder, which are applicable to any such plan;
provided further that neither the Company nor any Subsidiary will permit any event or condition to exist that would permit any such plan to be terminated under circumstances that would cause any material lien provided for in section
4068 of ERISA to attach to the assets of the Company or any Subsidiary. 
 (ii) The Company shall maintain, and cause each Subsidiary to
maintain, such permits, licenses, franchises, authorizations and clearances (“Permits”) of governmental or regulatory authorities, including, without limitation, the Food and Drug Administration (the
“FDA”) of the U.S. Department of Health and Human Services and/or any committee thereof, as are necessary to own, lease and operate its properties and to conduct its business as now conducted and as currently proposed to be
conducted; the Company shall fulfill and perform, and cause each Subsidiary to fulfill and perform, all such material obligations with respect to the Permits; and the Company shall conduct or sponsor, and cause each Subsidiary to conduct or sponsor,
feasibility, pre-clinical, clinical and other studies and tests in accordance with standard medical and scientific research procedures. 

(k) Compliance with Environmental Laws. The Company shall comply, and cause each Subsidiary to comply, with the provisions of all
federal, state and local 

  
 19 

 
environmental, health and safety laws, codes and ordinances and all rules and regulations promulgated thereunder, and the Company shall maintain, and cause each Subsidiary to maintain, all
federal, state and local permits, licenses, certificates and approvals known to the Company or any subsidiary to be required relating to (i) air emissions, (ii) discharges to surface water or ground water, (iii) noise emissions,
(iv) solid or liquid waste disposal, (v) the use, generation, storage, transportation or disposal of toxic or hazardous substances or wastes (intended hereby and hereafter to include any and all such materials listed in any federal, state
or local law, code or ordinance and all rules and regulations promulgated thereunder, as hazardous or potentially hazardous), or (vi) other environmental, health and safety matters. 

(l) Financings. The Company shall promptly, fully and in detail, inform the Board of any discussions, offers or contracts relating to
possible financings of any nature for the Company, whether initiated by the Company or any other Person, except for arrangements with trade creditors. 

(m) Nondisclosure and Inventions Agreements. The Company shall require each officer, employee and consultant of the Company, and cause
each Subsidiary to require each officer, employee and consultant of such Subsidiary, to enter into a Nondisclosure and Assignment of Inventions Agreement, in form and substance reasonably satisfactory to the Investors, prior to the commencement of
such officer’s, employee’s or consultant’s employment or consulting relationship with the Company or Subsidiary, as applicable. The Company shall require, and cause each Subsidiary to require, all key employees to enter into
non-competition and non-solicitation agreements covering a one year period following termination of employment in a form or forms approved by the Board, including a majority of the Preferred Directors. 

(n) Use of Proceeds. The Company shall expend the proceeds from the sale of the Series B Preferred Stock for working capital and
general corporate purposes and otherwise as determined by the Board from time to time. 
 (o) Quarterly Expense Reports. The Company
shall provide to the Board, on no less than a quarterly basis, a detailed expense report from the Company’s Chief Executive Officer. 

(p) Market Standoff Agreements. The Company will require all future purchasers of Capital Stock of the Company prior to the initial
public offering of the Company’s securities to execute a market standoff agreement in which the holders agree, if so requested by the Company or any underwriter’s representative in connection with an initial public offering, not to sell or
otherwise transfer any securities of the Company during a period of up to 180 days following the effective date of the registration statement. 

(q) Material Change; Litigation. The officers of the Company will promptly advise the Investors and the Board of any material adverse
change in the business or condition, financial or otherwise, of the Company and of each suit or proceeding commenced or threatened against the Company which, if adversely determined, in the reasonable judgment or the officers of the Company after
consultation with counsel, would result in a material adverse change. The Company will also promptly advise the Investors of the occurrence of any event that constitutes a material breach of any covenant contained herein. 

  
 20 

 (r) Preservation of Existence. The Company will preserve and maintain and, unless the
Company reasonably deems it not to be in its best interests, cause each Subsidiary to preserve and maintain, its corporate existence, rights, franchises and privileges in the jurisdictions of its organization, and qualify and remain qualified, and
cause each Subsidiary to qualify and remain qualified, as a foreign company in each jurisdiction in which such qualification is necessary or desirable in view of its business and operations or the ownership or lease of its properties, except when
the failure to be so qualified would not have a material adverse effect on the Company or its Subsidiaries. 
 (s) Reservation of Shares
of Common Stock. The Company will at all times reserve and keep available, solely for issuance and delivery upon the conversion of the Preferred Stock, all shares of Common Stock issuable upon such conversion. 

5.2. Negative Covenants. Without first obtaining the approval from the Board, including a majority of the Preferred Directors, the
Company will not, and will not permit any Subsidiary to: 
 (a) make any loan or advance to, or own any stock or other securities of, any
subsidiary or other corporation, partnership, or other entity; 
 (b) make any loan or advance to any employee or director, except advances
and similar expenditures in the ordinary course of business for travel or salary; 
 (c) hire, fire or change the compensation of any
officer of the Company, including base salaries, bonus programs and equity grants or appoint or remove the Company’s Chief Executive Officer; 

(d) approve any equity incentive plans or approve changes to any existing equity incentive plans or issue options with a different vesting
schedule than that which has been approved by the Board as the standard vesting schedule; 
 (e) approve or materially modify the
Company’s annual budget, business plan, financial plan or the standard operating procedures; 
 (f) enter into any employment agreement
other than the Company’s standard “at will” employment agreement; 
 (g) amend the KBI MSA in a manner that impacts the
equity compensation to be issued thereunder; 
 (h) take any of the actions listed under “Protective Provisions” in
Section 3.3 of the Certificate of Incorporation; or 
 (i) effect any merger or consolidation among the Company and any of its
Subsidiaries. 

  
 21 

 5.3. FCPA. The Company represents that it shall not (and shall not permit any of its
subsidiaries or affiliates or any of its or their respective directors, officers, managers, employees, independent contractors, representatives or agents to) promise, authorize or make any payment to, or otherwise contribute any item of value to,
directly or indirectly, to any third party, including any Non-U.S. Official (as (as such term is defined in the U.S. Foreign Corrupt Practices Act of 1977, as amended (the “FCPA”)), in each case, in violation of the FCPA, the
U.K. Bribery Act, or any other applicable anti-bribery or anti-corruption law. The Company further represents that it shall (and shall cause each of its subsidiaries and affiliates to) cease all of its or their respective activities, as well as
remediate any actions taken by the Company, its subsidiaries or affiliates, or any of their respective directors, officers, managers, employees, independent contractors, representatives or agents in violation of the FCPA, the U.K. Bribery Act, or
any other applicable anti-bribery or anti-corruption law. The Company further represents that it shall (and shall cause each of its subsidiaries and affiliates to) maintain systems of internal controls (including, but not limited to, accounting
systems, purchasing systems and billing systems) to ensure compliance with the FCPA, the U.K. Bribery Act, or any other applicable anti-bribery or anti-corruption law. Upon request, the Company agrees to provide responsive information and/or
certifications concerning its compliance with applicable anti-corruption laws. The Company shall promptly notify each Investor if the Company becomes aware of any enforcement action pursuant to such laws. The Company shall, and shall cause any
direct or indirect subsidiary or entity controlled by it, whether now in existence or formed in the future, to comply with the FCPA. The Company shall use its best efforts to cause any direct or indirect subsidiary, whether now in existence or
formed in the future, to comply in all material respects with all applicable laws. 
 5.4. Right to Conduct Activities. The Company
hereby agrees and acknowledges that each of LV and NBV (together with their respective Affiliates) is a professional investment fund, or a venture investment arm of its Affiliates, and as such invests in numerous portfolio companies and has
Affiliates, some of which may be deemed competitive with the Company’s business (as currently conducted or as currently propose to be conducted). The Company hereby agrees that, to the extent permitted under applicable law, none of the
Investors shall be liable to the Company for any claim arising out of, or based upon, (i) the investment by such Investor in any entity competitive with the Company or the activities of such Investor’s Affiliates, or (ii) actions
taken by any partner, officer or other representative of the Investor to assist any such competitive company, whether or not such action was taken as a member of the board of directors of such competitive company or otherwise, and whether or not
such action has a detrimental effect on the Company; provided, however, that the foregoing shall not relieve (x) any of the Investors from liability associated with the unauthorized disclosure of the Company’s confidential information
obtained pursuant to this Agreement, or (y) any director or officer of the Company from any liability associated with his or her fiduciary duties to the Company. 

5.5. Expiration of Covenants. The covenants set forth in this Section 5 shall expire and be of no further force or effect upon the
effectiveness of a Qualified Public Offering. After such time, the Investors shall be entitled to receive such annual and quarterly reports as the Company shall distribute to its stockholders generally. 

  
 22 

 Section 6. 

MISCELLANEOUS 
 6.1.
Additional Investors. Notwithstanding anything to the contrary contained herein, if the Company issues additional shares of the Series B Preferred Stock after the date hereof, whether to Additional Closing Purchasers (as defined in the
Purchase Agreement) pursuant to the Purchase Agreement or to KBI pursuant to the KBI MSA, any such purchaser of Series B Preferred Stock may become a party to this Agreement by executing and delivering an additional counterpart signature page to
this Agreement, and thereafter shall be deemed an “Investor” for all purposes hereunder. No action or consent by the Investors shall be required for such joinder to this Agreement by KBI or any Additional Closing Purchaser, so long as KBI
or such Additional Closing Purchaser has agreed in writing to be bound by all of the obligations as an “Investor” hereunder. Any joinder to this Agreement by additional purchasers of Series B Preferred Stock other than KBI or Additional
Closing Purchasers shall require the approval of both LV and NBV for so long as each of LV and NBV and their Affiliates hold at least 5,000,000 shares of Common Stock of the Company (including shares of Common Stock issued or issuable upon
conversion of Preferred Stock), which number is subject to appropriate adjustment for all stock splits, dividends, combinations, recapitalizations and the like. 

6.2. Governing Law. This Agreement shall be governed by, and construed and interpreted in accordance with the laws of the State of
Delaware as applied to agreements among Delaware residents made and to be performed entirely within the State of Delaware. 
 6.3.
Successors and Assigns. Except as otherwise expressly provided herein, the provisions hereof shall inure to the benefit of, and be binding upon, the successors, assigns, heirs, executors and administrators of the parties hereto. 

6.4. Entire Agreement. This Agreement constitutes the full and entire understanding and agreement among the parties with regard to the
subjects hereof. Nothing in this Agreement, express or implied, is intended to confer upon any party, other than the parties hereto and their successors and assigns, any rights, remedies, obligations or liabilities under or by reason of this
Agreement, except as expressly provided herein. Upon the effectiveness of this Agreement, the Prior Agreement shall be deemed amended and restated and superseded and replaced in its entirety by this Agreement, and shall be of no further force or
effect. 
 6.5. Severability. Any invalidity, illegality or limitation of the enforceability with respect to any Holder of any one or
more of the provisions of this Agreement, or any part thereof, whether arising by reason of the law of any such Person’s domicile or otherwise, shall in no way affect or impair the validity, legality or enforceability of this Agreement with
respect to any other Holder. In case any provision of this Agreement shall be invalid, illegal or unenforceable, it shall to the extent practicable, be modified so as to make it valid, legal and enforceable and to retain as nearly as practicable the
intent of the parties, and the validity, legality, and enforceability of the remaining provisions shall not in any way be affected or impaired thereby. 

  
 23 

 6.6. Amendment and Waiver. Except as otherwise expressly provided herein, any term of this
Agreement may be amended and the observance of any term of this Agreement may be waived (either generally or in a particular instance, either retroactively or prospectively and either for a specified period of time or indefinitely) with the written
consent of the Company and the Investors, or their transferees, holding at least 62% of the outstanding shares of Series B Preferred Stock, voting together as a single group (treated as if converted at the conversion rate then in effect and
including, for such purposes, shares of Common Stock into which any Series B Preferred Stock shall have been converted that are held by an Investor); provided that any amendment, termination or waiver to the terms of Section 3 (or
a defined term used therein) that occurs after the closing of the Qualified Public Offering shall instead require the written consent of the Company and Investors holding Registrable Securities representing at least 62% of the voting power of all
Registrable Securities then held by all Investors. Furthermore, clause (x) of Section 5.1(a) of this Agreement shall not be amended to increase the minimum number of shares required to be held by an existing Investor or its transferee in
order to receive the financial information described in Section 5.1(a) unless such amendment is approved by each existing Investor that would lose rights to such financial information as a result of such amendment. Notwithstanding the
foregoing, this Agreement may not be amended or terminated and the observance of any term hereof may not be waived with respect to any Investor without the written consent of such Investor, unless such amendment, termination, or waiver applies to
all Investors in the same fashion (it being agreed that a waiver of the provisions of Section 4 with respect to a particular transaction shall be deemed to apply to all Investors in the same fashion if such waiver does so by its terms,
notwithstanding the fact that certain Investors may nonetheless, by agreement with the Company, purchase securities in such transaction). Notwithstanding the foregoing provision, no such amendment or waiver shall reduce the aforesaid percentage of
Preferred Stock and Common Stock issued upon conversion thereof, the holders of which are required to consent to any waiver or supplemental agreement, without the consent of the holders of at least 75% of such Preferred Stock and Common Stock. Any
amendment or waiver effected in accordance with this Section 6.6 shall be binding upon the Company and each Investor and each transferee of the Registrable Securities. Upon the effectuation of each such amendment or waiver, the Company shall
promptly give written notice thereof to the Investors who have not previously consented thereto in writing. 
 6.7. Delays or
Omissions. No delay or omission to exercise any right, power or remedy accruing to the Company, the Investors, or any transferees upon any breach, default or noncompliance of the Investors or any transferee or the Company under this Agreement,
shall impair any such right, power or remedy, nor shall it be construed to be a waiver of any such breach, default or noncompliance, or any acquiescence therein, or of any similar breach, default or noncompliance thereafter occurring. It is further
agreed that any waiver, permit, consent or approval of any kind or character on the part of the Company or the Investors of any breach, default or noncompliance under this Agreement or any waiver on the Company’s or the Investors’ part of
any provisions or conditions of this Agreement must be in writing and shall be effective only to the extent specifically set forth in such writing and that all remedies, either under this Agreement, by law, or otherwise afforded to the Company and
the Investors, shall be cumulative and not alternative. 
 6.8. Notices, etc. All notices and other communications given or made
pursuant to this Agreement shall be in writing and shall be deemed effectively given upon the earlier of 

  
 24 

 
actual receipt or: (a) personal delivery to the party to be notified, (b) when sent, if sent by facsimile during normal business hours of the recipient, and if not sent during normal
business hours, then on the recipient’s next Business Day, (c) five (5) days after having been sent by registered or certified mail, return receipt requested, postage prepaid, or (d) one (1) Business Day after deposit with a
nationally recognized overnight courier, freight prepaid, specifying next Business Day delivery, with written verification of receipt. All communications shall be sent to the respective parties at their address as set forth on the signature page or
Exhibit A, or to such address or facsimile number as subsequently modified by written notice given in accordance with this Section 6.8. If notice is given to the Company, it shall be sent to 815-A Brazos Street, #101, marked “Attention:
Chief Executive Officer”; and a copy (which shall not constitute notice) shall also be sent to Fenwick & West, LLP, 555 California Street, San Francisco, CA 94104, Attn: Effie Toshav and Matthew Rossiter. 

6.9. Titles and Subtitles. The titles of the sections and subsections of this Agreement are for convenience of reference only and are
not to be considered in construing this Agreement. 
 6.10. Counterparts, Facsimile Signatures. This Agreement may be executed in two
or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument. Counterparts may be delivered via facsimile, electronic mail (including PDF or any electronic signature
complying with the U.S. federal ESIGN Act of 2000, e.g., www.docusign.com) or other transmission method and any counterpart so delivered shall be deemed to have been duly and validly delivered and be valid and effective for all purposes. 

[The next page is the signature page.] 

  
 25 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
  

							
	THE COMPANY				AEGLEA BIOTHERAPEUTICS, INC.
				
					By:		 /s/ David G. Lowe

					Name:		David G. Lowe
					Title:		President and Chief Executive Officer

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
  

									
	INVESTORS:		
			
	LILLY VENTURES FUND 1 LLC				NOVARTIS BIOVENTURES LTD.
					
	By:		 /s/ S. Edward Torres
				By:		 /s/ H. S. Zivi

	Name:		S. Edward Torres				Name:		H. S. Zivi
	Title:		Managing Director				Title:		Deputy Chairman
					
							By:		 /s/ Laurieann Chaikowsky

							Name:		Laurieann Chaikowsky
							Title:		Authorised Signatory
			
	THE O’LEARY FAMILY INVESTMENT TRUST				
					
	By:		  
				By:		  

	Name:		Brendan M. O’Leary				Name:		Jonathan L. Sessler
	Title:		Trustee						

  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE BOARD OF REGENTS OF THE
	UNIVERSITY OF TEXAS SYSTEM
		
	By:		 /s/ Daniel H. Sharphorn

			Daniel H. Sharphorn
			Vice Chancellor and General Counsel
	
	Approved by:
		
	By:		 /s/ Patricia D. Hurn

			Patricia D. Hurn
			Vice Chancellor for Research and Innovation
		
	By:		 /s/ Julie Goonewardene

			Julie Goonewardene
			Associate Vice Chancellor for Innovation
			and Strategic Investment

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	 VENROCK HEALTHCARE CAPITAL
 PARTNERS
II, L.P.

	By:		VHCP Management II, LLC
	Its:		General Partner
		
	By:		 /s/ signature illegible

			Authorized Signatory
	
	VHCP CO-INVESTMENT HOLDINGS II, LLC
	By:		VHCP Management II, LLC
	Its:		Manager
		
	By:		 /s/ signature illegible

			Authorized Signatory

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	JENNISON GLOBAL HEALTHCARE
	MASTER FUND, LTD. (the “Fund”)
		
	By:		Jennison Associates LLC, as the
			Investment Manager of the Fund
		
	By:		 /s/ David Chan

	Name:		David Chan
	Title:		Managing Director of
			Jennison Associates LLC

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	RA CAPITAL HEALTHCARE FUND, LP
		
	By:		 /s/ Peter Kolchinsky

	Name:		Peter Kolchinsky
	Title:		Manager

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	ABG II-AEGLEA LIMITED
		
	By:		 /s/ Yeh Shan-ju

	Name:		Yeh Shan-ju
	Title:		Director

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	ROCK SPRINGS CAPITAL MASTER
	FUND LP
		
	By:		Rock Springs GP LLC
		
	Its:		General Partner
		
	By:		 /s/ Graham McPhail

	Name:		Graham McPhail
	Title:		Managing Director
			Rock Springs Capital
			650 S. Exeter St., Suite 1070
			Baltimore, MD 21202

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	COWEN AB INVESTMENT LLC
		
	By:		 /s/ Stephen Lasota

	Name:		Stephen Lasota
	Title:		Authorized Signatory

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	ORBIMED PRIVATE INVESTMENTS V, LP
		
	By:		OrbiMed Capital GP V LLC
	Its:		General Partner
		
	By:		OrbiMed Advisors LLC
	Its:		Managing Member
		
	By:		 /s/ Carl Gordon

	Name:		Carl Gordon
	Title:		Member

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE O’LEARY FAMILY INVESTMENT TRUST
	BRENDAN M. O’LEARY, TRUSTEE
		
	By:		 /s/ Brendan M. O’Leary

	Name:		Brendan M. O’Leary
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

	
	 /s/ Jonathan L. Sessler

	Jonathan L. Sessler

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

	
	 /s/ Mary S. Newman

	Mary S. Newman

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

							
	SELF-DIRECTED IRA SERVICES, INC., Custodian PBO: Charles York IRA # 201419166				SELF DIRECTED IRA SERVICES, INC. CUSTODIAN, FBO: CHARLES N. YORK II, IRA #201419166
				
	 /s/ signature illegible
                    3-6-2015                
				By:		 /s/ Charles N. York II

	Authorized Signature                     Date				Name:		Charles N. York II
			
					CHARLES N. YORK II
				
					By:		 /s/ Charles N. York II

					Name:		Charles N. York II

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	DAVID G. LOWE & ANN M. LOWE,
	AS TRUSTEE OF THE LOWE
	FAMILY TRUST DATED DECEMBER 11, 1991
		
	By:		 /s/ David G. Lowe

	Name:		David G. Lowe
	Title:		Trustee
		
	By:		 /s/ Ann M. Lowe

	Name:		Ann M. Lowe
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

	
	 /s/ Joseph E. Tyler

	Joseph E. Tyler

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

	
	 /s/ Kristin J. Hora Beach

	Kristin J. Hora Beach

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	STEVEN T. WEBER
		
	By:		 /s/ Steven T. Weber

	Name:		Steven T. Weber

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE SCOTT W. AND SUSAN D. ROWLINSON
	JOINT TRUST AGREEMENT
		
	By:		 /s/ Scott W. Rowlinson

	Name:		Scott W. Rowlinson
	Title:		Trustee
		
	By:		 /s/ Susan D. Rowlinson

	Name:		Susan D. Rowlinson
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	SUSAN ALTERS AND DANIEL ABRAMOVITCH JOINT TENANTS WITH RIGHTS OF SURVIVORSHIP
		
	By:		 /s/ Susan Alters

			Susan Alters
		
	By:		 /s/ Daniel Abramovitch

			Daniel Abramovitch

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	ZUKE LLC
		
	By:		 /s/ Conor Richardson

	Name:		Conor Richardson
	Title:		Chief Executive Officer

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

	
	 /s/ Louis C. Bock

	Louis C. Bock

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	 THE FREUND/GRAIS REVOCABLE TRUST

D/T/D MARCH 29, 2005

	JOHN G. FREUND, TRUSTEE
		
	By:		 John G. Freund

	Name:		John G. Freund
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	HORNBLOWER CAPITAL HOLDINGS, LLC
		
	By:		 /s/ Josiah Hornblower

	Name:		Josiah Hornblower
	Title:		Managing Member

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Hunter Family Trust, LLC
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Robert W. Horstman
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Robert W. Horstman
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Trustee of Managing Member
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Stone Dock Investors
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Josiah Hornblower
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Josiah Hornblower
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Managing Partner
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Sauder Property Company Ltd.
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ John Sauder
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 John Sauder
						
			(Print/Type Signatory’s Name)						
					
	Title:		 General Partner
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	WOODPECKER PHARMA HOLDINGS, LLC
		
	By:		 /s/ Eric Stein

	Name:		Eric Stein
	Title:		Managing Member

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	ATHON FAMILY INVESTMENTS, L.P.
		
	By:		 /s/ Merrell Athon

	Name:		Merrell Athon
	Title:		President of the General Partner

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Mark Plunkett

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Mark Plunkett

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Martin D. Cohen

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Martin D. Cohen

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s								
	Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Kawaja Living Trust Dated June 30, 2008
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Christopher Kawaja, TTEE
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s								
	Name:		 Christopher Kawaja
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Trustee
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	IFS COATINGS, INC.
		
	By:		 /s/ Glynn Mason

	Name:		Glynn Mason
	Title:		President

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	MORTON R. BRANZBURG
		
	By:		 /s/ Morton R. Branzburg

	Name:		Morton R. Branzburg

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 SHKH, LLC
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Stephen Hochschuler
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s								
	Name:		 Stephen Hochschuler
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Manager
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 WSHL II, Ltd.
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ William S. Harte
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s								
	Name:		 William S. Harte
						
			(Print/Type Signatory’s Name)						
					
	Title:		 General Partner
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Brett Hogan

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Brett Hogan

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Marvin Belsky

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Marvin Belsky

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Paul Marc Belsky

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Paul Marc Belsky

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 The Ephraim Heller Separate Property Trust dated October 6, 2006
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Ephraim Heller
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Ephraim Heller
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Trustee
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE REBECCA ELIZABETH HELLER TRUST
		
	By:		 /s/ David G. Chandler

	Name:		David G. Chandler
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE JONAH HELLER TRUST
		
	By:		 /s/ David G. Chandler

	Name:		David G. Chandler
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE BOAZ HELLER TRUST
		
	By:		 /s/ David G. Chandler

	Name:		David G. Chandler
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	THE MARK FULLER TRUST
		
	By:		 /s/ Mark A. Fuller III

	Name:		Mark A. Fuller III
	Title:		Trustee

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Oliver A. Evans

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Oliver A. Evans

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Capital Partnership (ACG), L.P.
 By: Capital
Partners (ACB), L.L.C.
 its general partner
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Jay H. Hebert
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Jay H. Hebert
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Vice President
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Jay H. Hebert as Trustee of the Ann Chandler Bass 2010 Children’s Trust U/A/D 12-29-2010
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Jay H. Hebert
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Jay H. Hebert
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Trustee
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

			
	SKM PARTNERSHIP, LTD
		
	By:		 /s/ Scott Martin

	Name:		Scott Martin
	Title:		President

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Guy Levy

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Guy Levy

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		  
						
			(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 New Ground Ventures, LP
				Name:		  

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		 /s/ Zachary Zeitlin
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s Name:		 Zachary Zeitlin
						
			(Print/Type Signatory’s Name)						
					
	Title:		 Manager
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		  
				Name:		 Carson Lee Randolph Yost (Separate)

			(Print/Type Precise Legal Name of Entity)						(Print/Type Precise Legal Name of Individual)
					
	By:		  
				By:		 /s/ Carson Lee Randolph Yost

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s		  
						
	 Name:
		(Print/Type Signatory’s Name)						
					
	Title:		  
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 IN WITNESS WHEREOF, this Amended and Restated Investor Rights Agreement has been duly executed
and delivered by the parties as of the date first above written. 
 INVESTOR: 

 

									
	 [FOR ENTITY INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]
				 [FOR INDIVIDUAL INVESTOR USE

FOLLOWING SIGNATURE BLOCK:]

					
	Name:		 Goff Aeglea Holdings, LLC
 By:
Goff Capital, Inc.
 Its: Manager
				Name:		  

								(Print/Type Precise Legal Name of Individual)
								
			(Print/Type Precise Legal Name of Entity)						
					
	By:		 /s/ John C. Goff
				By:		  

			(Sign Here)						(Sign Here)
					
	Authorized Signatory’s		 John C. Goff
						
	Name:		(Print/Type Signatory’s Name)						
					
	Title:		 President
						
			(Print/Type Signatory’s Title)						
					
	Address:		  
				Address:		  

			  
						  

			  
						  

			  
						  

  
 [Signature Page to
Amended and Restated Investor Rights Agreement] 

 EXHIBIT A 

SCHEDULE OF INVESTORS 
  

					
	 	  	 Name and Address of Investor
	  	 
		  	 Lilly Ventures Fund I LLC
	  	
			
		  	 Novartis Bioventures Ltd.
	  	
			
		  	 The Board of Regents of the University of Texas System
	  	
			
		  	 Venrock Healthcare Capital Partners II, L.P.
	  	
			
		  	 VHCP Co-Investment Holdings II, LLC
	  	
			
		  	 Jennison Global Healthcare Master Fund, Ltd.
	  	
			
		  	 RA Capital Healthcare Fund, LP
	  	
			
		  	 ABG II-Aeglea Limited
	  	
			
		  	 Rock Springs Capital Master Fund LP
	  	
			
		  	 Cowen AB Investment LLC
	  	
			
		  	 OrbiMed Private Investments V, LP
	  	
			
		  	 Hornblower Capital Holdings, LLC
	  	
			
		  	 Hunter Family Trust
	  	
			
		  	 Stone Dock Investors
	  	
			
		  	 Sauder Property Company Ltd.
	  	
			
		  	 Woodpecker Pharma Holdings, LLC
	  	
			
		  	 Athon Family Investments, L.P.
	  	
			
		  	 Mark Barrett Plunkett
	  	
			
		  	 Martin D. Cohen
	  	
			
		  	 Christopher Kawaja, Trustee, Kawaja
	  	
			
		  	 IFS Coatings, Inc.
	  	
			
		  	 Morton R. Branzburg
	  	
			
		  	 SHKH, LLC
	  	
			
		  	 WSHL II, Ltd.
	  	
			
		  	 Brett Williams Hogan
	  	

  
 A-1 

					
			Dr. Marvin Belsky		
			
			Dr. Paul Belsky		
			
			Ephraim Heller, Trustee, The Ephraim Heller Separate Property Trust dated October 6, 2006		
			
			David G. Chandler, Trustee, The Rebecca Elizabeth Heller Trust		
			
			David G. Chandler, Trustee, The Jonah Heller Trust		
			
			David G. Chandler, Trustee, The Boaz Heller Trust		
			
			Mark A. Fuller III Rev. Trust of 2007		
			
			Oliver Anthony Evans		
			
			Jay H. Hebert, as Trustee of the Anne Chandler Bass 2010 Children’s Trust U/A/D 12/29/2010		
			
			Capital Partnership (ACB), L.P.		
			
			SKM Partnership, Ltd		
			
			Guy Levy		
			
			New Ground Ventures, LP		
			
			Carson Lee Randolph Yost		
			
			Goff Aeglea Holdings, LLC		
			
			 The O’Leary Family Investment Trust

Brendan M. O’Leary, Trustee
		
			
			Jonathan L. Sessler		
			
			Mary S. Newman		
			
			Self Directed IRA Services, Inc. Custodian, FBO: Charles N. York II, IRA #201419166		
			
			Charles N. York II		
			
			David G. Lowe & Ann M. Lowe, as Trustee of the Lowe Family Trust Dated December 11, 1991		
			
			Joseph E. Tyler		
			
			Kristin J. Hora Beach		

  
 A-2 

					
			
			Steven T. Weber		
			
			The Scott W. and Susan D. Rowlinson Joint Trust Agreement		
			
			 Susan Alters and Daniel Abramovitch
 Joint
Tenants with Rights of Survivorship
		
			
			Zuke LLC		
			
			Louis C. Bock		
			
			 The Freund/Grais Revocable Trust d/t/d March 29, 2005

John G. Freund, Trustee
		
			
			KBI Biopharma, Inc.		

  
 A-3EX-10.2

 EXHIBIT 10.2 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

As Adopted on March 10, 2015 

1. PURPOSE. The purpose of this Plan is to provide incentives to attract, retain and motivate eligible persons whose present and
potential contributions are important to the success of the Company, its Parent and Subsidiaries by offering eligible persons an opportunity to participate in the Company’s future performance through the grant of Awards covering Shares.
Capitalized terms not defined in the text are defined in Section 14 hereof. Although this Plan is intended to be a written compensatory benefit plan within the meaning of Rule 701, grants may be made pursuant to this Plan that do not
qualify for exemption under Rule 701 or Section 25102(o). Any requirement of this Plan that is required in law only because of Section 25102(o) need not apply if the Committee so provides. 

2. SHARES SUBJECT TO THE PLAN. 

2.1 Number of Shares Available. Subject to Sections 2.2 and 11 hereof, the total number of Shares reserved and available for
grant and issuance pursuant to this Plan will be 12,901,499 Shares. Subject to Sections 2.2 and 11 hereof, Shares subject to Awards that are cancelled, forfeited, settled in cash, used to pay withholding obligations or pay the exercise price of an
Option or that expire by their terms at any time will again be available for grant and issuance in connection with other Awards. In the event that Shares previously issued under the Plan are reacquired by the Company pursuant to a forfeiture
provision, right of first refusal, or repurchase by the Company, such Shares shall be added to the number of Shares then available for issuance under the Plan. At all times the Company will reserve and keep available a sufficient number of Shares as
will be required to satisfy the requirements of all Awards granted and outstanding under this Plan. In no event shall the total number of Shares issued (counting each reissuance of a Share that was previously issued and then forfeited or repurchased
by the Company as a separate issuance) under the Plan upon exercise of ISOs exceed 25,802,998 Shares (adjusted in proportion to any adjustments under Section 2.2 hereof) over the term of the Plan (the “ISO Limit”).
Subject to Sections 2.2 and 11 hereof, in the event that the number of Shares reserved for issuance under the Plan is increased, the ISO Limit shall be automatically increased by such number of Shares such that the ISO Limit equals (a) two
(2) multiplied by (b) the number of Shares reserved for issuance under the Plan. 
 2.2 Adjustment of Shares. In the
event that the number of outstanding shares of the Company’s Common Stock is changed by a stock dividend, recapitalization, stock split, reverse stock split, subdivision, combination, reclassification or other change in the capital structure of
the Company affecting Shares without consideration, then in order to prevent diminution or enlargement of the benefits or potential benefits intended to be made available under the Plan (a) the number of Shares reserved for issuance under this
Plan, (b) the Exercise Prices of and number of Shares subject to outstanding Options and SARs, and (c) the Purchase Prices of and/or number of Shares subject to other outstanding Awards will (to the extent

  
 1 

 
appropriate) be proportionately adjusted, subject to any required action by the Board or the stockholders of the Company and compliance with applicable securities laws; provided,
however, that fractions of a Share will not be issued but will either be paid in cash at the Fair Market Value of such fraction of a Share or will be rounded down to the nearest whole Share, as determined by the Committee. 

3. PLAN FOR BENEFIT OF SERVICE PROVIDERS. 

3.1 Eligibility. The Committee will have the authority to select persons to receive Awards. ISOs (as defined in Section 4
hereof) may be granted only to employees (including officers and directors who are also employees) of the Company or of a Parent or Subsidiary of the Company. NQSOs (as defined in Section 4 hereof) and all other types of Awards may be granted
to employees, officers, directors and consultants of the Company or any Parent or Subsidiary of the Company; provided such consultants render bona fide services not in connection with the offer and sale of securities in a
capital-raising transaction when Rule 701 is to apply to the Award granted for such services. A person may be granted more than one Award under this Plan. 

3.2 No Obligation to Employ. Nothing in this Plan or any Award granted under this Plan will confer or be deemed to confer on any
Participant any right to continue in the employ of, or to continue any other relationship with, the Company or any Parent or Subsidiary or limit in any way the right of the Company or any Parent or Subsidiary to terminate Participant’s
employment or other relationship at any time, with or without Cause. 
 4. OPTIONS. The Committee may grant Options to
eligible persons described in Section 3 hereof and will determine whether such Options will be Incentive Stock Options within the meaning of the Code (“ISOs”) or Nonqualified Stock Options
(“NQSOs”), the number of Shares subject to the Option, the Exercise Price of the Option, the period during which the Option may be exercised, and all other terms and conditions of the Option, subject to the following. 

4.1 Form of Option Grant. Each Option granted under this Plan will be evidenced by an Award Agreement which will expressly
identify the Option as an ISO or an NQSO (“Stock Option Agreement”), and will be in such form and contain such provisions (which need not be the same for each Participant) as the Committee may from time to time approve, and
which will comply with and be subject to the terms and conditions of this Plan. 
 4.2 Date of Grant. The date of grant of an
Option will be the date on which the Committee makes the determination to grant such Option, unless a later date is otherwise specified by the Committee. The Stock Option Agreement and a copy of this Plan will be delivered to the Participant within
a reasonable time after the granting of the Option. 
 4.3 Exercise Period. Options may be exercisable within the time or upon
the events determined by the Committee in the Award Agreement and may be awarded as immediately exercisable but subject to repurchase pursuant to Section 10 hereof or may be exercisable within the times or upon the events determined by the
Committee as set forth in the Stock Option Agreement governing such Option; provided, however, that (a) no Option will be 

  
 2 

 
exercisable after the expiration of ten (10) years from the date the Option is granted; and (b) no ISO granted to a person who directly or by attribution owns more than ten percent
(10%) of the total combined voting power of all classes of stock of the Company or of any Parent or Subsidiary (“Ten Percent Stockholder”) will be exercisable after the expiration of five (5) years from the date the
ISO is granted. The Committee also may provide for Options to become exercisable at one time or from time to time, periodically or otherwise, in such number of Shares or percentage of Shares as the Committee determines. 

4.4 Exercise Price. The Exercise Price of an Option will be determined by the Committee when the Option is granted and shall not
be less than the Fair Market Value per Share unless expressly determined in writing by the Committee on the Option’s date of grant; provided that the Exercise Price of an ISO granted to a Ten Percent Stockholder will not be less
than one hundred ten percent (110%) of the Fair Market Value of the Shares on the date of grant. Payment for the Shares purchased must be made in accordance with Section 8 hereof. 

4.5 Method of Exercise. Options may be exercised only by delivery to the Company of a written stock option exercise agreement
(the “Exercise Agreement”) in a form approved by the Committee (which need not be the same for each Participant). The Exercise Agreement will state (a) the number of Shares being purchased, (b) the restrictions
imposed on the Shares purchased under such Exercise Agreement, if any, and (c) such representations and agreements regarding Participant’s investment intent and access to information and other matters, if any, as may be required or
desirable by the Company to comply with applicable securities laws. Each Participant’s Exercise Agreement may be modified by (i) agreement of Participant and the Company or (ii) substitution by the Company, upon becoming a public
company, in order to add the payment terms set forth in Section 8.1 that apply to a public company and such other terms as shall be necessary or advisable in order to exercise a public company option. Upon exercise of an Option, Participant
shall execute and deliver to the Company the Exercise Agreement then in effect, together with payment in full of the Exercise Price for the number of Shares being purchased and payment of any applicable taxes. No adjustment will be made for a
dividend or other right for which the record date is prior to the date the Shares are issued, except as provided in Section 2.2 of the Plan. Exercising an Option in any manner will decrease the number of Shares thereafter available, both for
purposes of the Plan and for sale under the Option, by the number of Shares as to which the Option is exercised. 
 4.6
Termination. Subject to earlier termination pursuant to Sections 11 and 13.3 hereof and notwithstanding the exercise periods set forth in the Stock Option Agreement, exercise of an Option will always be subject to the following terms
and conditions. 
 4.6.1 Other than Death or Disability or for Cause. If the Participant is Terminated for any reason other than
death, Disability or for Cause, then the Participant may exercise such Participant’s Options only to the extent that such Options are exercisable as to Vested Shares upon the Termination Date or as otherwise determined by the Committee. Such
Options must be exercised by the Participant, if at all, as to all or some of the Vested Shares calculated as of the Termination Date or such other date determined by the Committee, within three (3) months after the Termination Date (or within
such shorter time period, not less than thirty (30) days, or within such longer time period after the Termination Date as may be determined by the Committee, with any exercise beyond three (3) months after the date Participant ceases to be
an employee deemed to be an NQSO) but in any event, no later than the expiration date of the Options. 

  
 3 

 4.6.2 Death or Disability. If the Participant is Terminated because of Participant’s
death or Disability (or the Participant dies within three (3) months after a Termination other than for Cause), then Participant’s Options may be exercised only to the extent that such Options are exercisable as to Vested Shares by
Participant on the Termination Date or as otherwise determined by the Committee. Such options must be exercised by Participant (or Participant’s legal representative or authorized assignee), if at all, as to all or some of the Vested Shares
calculated as of the Termination Date or such other date determined by the Committee, within twelve (12) months after the Termination Date (or within such shorter time period, not less than six (6) months, or within such longer time
period, after the Termination Date as may be determined by the Committee, with any exercise beyond (a) three (3) months after the date Participant ceases to be an employee when the Termination is for any reason other than the
Participant’s death or disability, within the meaning of Section 22(e)(3) of the Code, or (b) twelve (12) months after the date Participant ceases to be an employee when the Termination is for Participant’s disability,
within the meaning of Section 22(e)(3) of the Code, deemed to be an NQSO) but in any event no later than the expiration date of the Options. 

4.6.3 For Cause. If the Participant is terminated for Cause, the Participant may exercise such Participant’s Options, but not to
an extent greater than such Options are exercisable as to Vested Shares upon the Termination Date and Participant’s Options shall expire on such Participant’s Termination Date, or at such later time and on such conditions as are determined
by the Committee. 
 4.7 Limitations on Exercise. The Committee may specify a reasonable minimum number of Shares that may be
purchased on any exercise of an Option, provided that such minimum number will not prevent Participant from exercising the Option for the full number of Shares for which it is then exercisable. 

4.8 Limitations on ISOs. The aggregate Fair Market Value (determined as of the date of grant) of Shares with respect to which
ISOs are exercisable for the first time by a Participant during any calendar year (under this Plan or under any other incentive stock option plan of the Company or any Parent or Subsidiary of the Company) will not exceed One Hundred Thousand Dollars
($100,000). If the Fair Market Value of Shares on the date of grant with respect to which ISOs are exercisable for the first time by a Participant during any calendar year exceeds One Hundred Thousand Dollars ($100,000), then the Options for the
first One Hundred Thousand Dollars ($100,000) worth of Shares to become exercisable in such calendar year will be ISOs and the Options for the amount in excess of One Hundred Thousand Dollars ($100,000) that become exercisable in that calendar year
will be NQSOs. In the event that the Code or the regulations promulgated thereunder are amended after the Effective Date (as defined in Section 13.1 hereof) to provide for a different limit on the Fair Market Value of Shares permitted to be
subject to ISOs, then such different limit will be automatically incorporated herein and will apply to any Options granted after the effective date of such amendment. 

4.9 Modification, Extension or Renewal. The Committee may modify, extend or renew outstanding Options and authorize the grant of
new Options in substitution 

  
 4 

 
therefor, provided that any such action may not, without the written consent of a Participant, impair any of such Participant’s rights under any Option previously granted. Any
outstanding ISO that is modified, extended, renewed or otherwise altered will be treated in accordance with Section 424(h) of the Code. Subject to Section 4.10 hereof, the Committee may reduce the Exercise Price of outstanding Options
without the consent of Participants by a written notice to them; provided, however, that the Exercise Price may not be reduced below the minimum Exercise Price that would be permitted under Section 4.4 hereof for
Options granted on the date the action is taken to reduce the Exercise Price. 
 4.10 No Disqualification. Notwithstanding any
other provision in this Plan, no term of this Plan relating to ISOs will be interpreted, amended or altered, nor will any discretion or authority granted under this Plan be exercised, so as to disqualify this Plan under Section 422 of the Code
or, without the consent of the Participant, to disqualify any Participant’s ISO under Section 422 of the Code. 
 5.
RESTRICTED STOCK. A Restricted Stock Award is an offer by the Company to sell to an eligible person Shares that are subject to certain specified restrictions. The Committee will determine to whom an offer will be made, the number of
Shares the person may purchase, the Purchase Price, the restrictions to which the Shares will be subject, and all other terms and conditions of the Restricted Stock Award, subject to the following terms and conditions. 

5.1 Form of Restricted Stock Award. All purchases under a Restricted Stock Award made pursuant to this Plan will be evidenced by
an Award Agreement (“Restricted Stock Purchase Agreement”) that will be in such form (which need not be the same for each Participant) as the Committee will from time to time approve, and will comply with and be subject to
the terms and conditions of this Plan. The Restricted Stock Award will be accepted by the Participant’s execution and delivery of the Restricted Stock Purchase Agreement and full payment for the Shares to the Company within thirty
(30) days from the date the Restricted Stock Purchase Agreement is delivered to the person. If such person does not execute and deliver the Restricted Stock Purchase Agreement along with full payment for the Shares to the Company within such
thirty (30) days, then the offer will terminate, unless otherwise determined by the Committee. 
 5.2 Purchase Price. The
Purchase Price of Shares sold pursuant to a Restricted Stock Award will be determined by the Committee on the date the Restricted Stock Award is granted or at the time the purchase is consummated. Payment of the Purchase Price must be made in
accordance with Section 8 hereof. 
 5.3 Dividends and Other Distributions. Participants holding Restricted Stock will be
entitled to receive all dividends and other distributions paid with respect to such Shares, unless the Committee provides otherwise at the time of award. If any such dividends or distributions are paid in Shares, the Shares will be subject to the
same restrictions on transferability and forfeitability as the Shares of Restricted Stock with respect to which they were paid. 

  
 5 

 5.4 Restrictions. Restricted Stock Awards may be subject to the restrictions set
forth in Sections 9 and 10 hereof or, with respect to a Restricted Stock Award to which Section 25102(o) is to apply, such other restrictions not inconsistent with Section
 25102(o). 

6. RESTRICTED STOCK UNITS. 

6.1 Awards of Restricted Stock Units. A Restricted Stock Unit (“RSU”) is an Award covering a number of
Shares that may be settled in cash, or by issuance of those Shares at a date in the future. No Purchase Price shall apply to an RSU settled in Shares. All grants of Restricted Stock Units will be evidenced by an Award Agreement that will be in such
form (which need not be the same for each Participant) as the Committee will from time to time approve, and will comply with and be subject to the terms and conditions of this Plan. 

6.2 Form and Timing of Settlement. To the extent permissible under applicable law, the Committee may permit a Participant to
defer payment under a RSU to a date or dates after the RSU is earned, provided that the terms of the RSU and any deferral satisfy the requirements of Section 409A of the Code (or any successor) and any regulations or rulings
promulgated thereunder. Payment may be made in the form of cash or whole Shares or a combination thereof, all as the Committee determines. 

7. STOCK APPRECIATION RIGHTS. 

7.1 Awards of SARs. Stock Appreciation Rights (“SARs”) may be settled in cash, or Shares (which may
consist of Restricted Stock or RSUs), having a value equal to the value determined by multiplying the difference between the Fair Market Value on the date of exercise over the Exercise Price and the number of Shares with respect to which the SAR is
being settled. All grants of SARs made pursuant to this Plan will be evidenced by an Award Agreement that will be in such form (which need not be the same for each Participant) as the Committee will from time to time approve, and will comply with
and be subject to the terms and conditions of this Plan. 
 7.2 Exercise Period and Expiration Date. A SAR will be exercisable
within the times or upon the occurrence of events determined by the Committee and set forth in the Award Agreement governing such SAR. The Award Agreement shall set forth the Expiration Date; provided that no SAR will be exercisable
after the expiration of ten years from the date the SAR is granted. 
 7.3 Exercise Price. The Committee will determine the
Exercise Price of the SAR when the SAR is granted, and which may not be less than the Fair Market Value on the date of grant and may be settled in cash or in Shares. 

7.4 Termination. Subject to earlier termination pursuant to Sections 11 and 13.1 hereof and notwithstanding the exercise
periods set forth in the Award Agreement, exercise of SARs will always be subject to the following terms and conditions. 
 7.4.1 Other
than Death or Disability or for Cause. If the Participant is Terminated for any reason other than death, Disability or for Cause, then the Participant may exercise such Participant’s SARs only to the extent that such SARs are exercisable as
to Vested 

  
 6 

 
Shares upon the Termination Date or as otherwise determined by the Committee. SARs must be exercised by the Participant, if at all, as to all or some of the Vested Shares calculated as of the
Termination Date or such other date determined by the Committee, within three (3) months after the Termination Date (or within such shorter time period, not less than thirty (30) days, or within such longer time period after the
Termination Date as may be determined by the Committee) but in any event, no later than the expiration date of the SARs. 
 7.4.2 Death
or Disability. If the Participant is Terminated because of Participant’s death or Disability (or the Participant dies within three (3) months after a Termination other than for Cause), then Participant’s SARs may be exercised only
to the extent that such SARs are exercisable as to Vested Shares by Participant on the Termination Date or as otherwise determined by the Committee. Such SARs must be exercised by Participant (or Participant’s legal representative or authorized
assignee), if at all, as to all or some of the Vested Shares calculated as of the Termination Date or such other date determined by the Committee, within twelve (12) months after the Termination Date (or within such shorter time period, not
less than six (6) months, or within such longer time period after the Termination Date as may be determined by the Committee) but in any event no later than the expiration date of the SARs. 

7.4.3 For Cause. If the Participant is terminated for Cause, the Participant may exercise such Participant’s SARs, but not to an
extent greater than such SARs are exercisable as to Vested Shares upon the Termination Date and Participant’s SARs shall expire on such Participant’s Termination Date, or at such later time and on such conditions as are determined by the
Committee. 
 8. PAYMENT FOR PURCHASES AND EXERCISES. 

8.1 Payment in General. Payment for Shares acquired pursuant to this Plan may be made in cash (by check) or, where expressly
approved for the Participant by the Committee and where permitted by law: 
 (a) by cancellation of indebtedness of the Company owed to the
Participant; 
 (b) by surrender of shares of the Company that are clear of all liens, claims, encumbrances or security interests and:
(i) for which the Company has received “full payment of the purchase price” within the meaning of SEC Rule 144 (and, if such shares were purchased from the Company by use of a promissory note, such note has been fully paid with
respect to such shares) or (ii) that were obtained by Participant in the public market; 
 (c) by tender of a full recourse promissory
note having such terms as may be approved by the Committee and bearing interest at a rate sufficient to avoid imputation of income under Sections 483 and 1274 of the Code; provided, however, that Participants who are
not employees or directors of the Company will not be entitled to purchase Shares with a promissory note unless the note is adequately secured by collateral other than the Shares; provided, further, that the portion of
the Exercise Price or Purchase Price, as the case may be, equal to the par value (if any) of the Shares must be paid in cash or other legal consideration permitted by the laws under which the Company is then incorporated or organized; 

  
 7 

 (d) by waiver of compensation due or accrued to the Participant from the Company for services
rendered; 
 (e) by participating in a formal cashless exercise program implemented by the Committee in connection with the Plan; 

(f) subject to compliance with applicable law, provided that a public market for the Company’s Common Stock exists, by exercising
through a “same day sale” commitment from the Participant and a broker-dealer whereby the Participant irrevocably elects to exercise the Award and to sell a portion of the Shares so purchased sufficient to pay the total Exercise Price or
Purchase Price, and whereby the broker-dealer irrevocably commits upon receipt of such Shares to forward the total Exercise Price or Purchase Price directly to the Company; or 

(g) by any combination of the foregoing or any other method of payment approved by the Committee. 

8.2 Withholding Taxes. 

8.2.1 Withholding Generally. Whenever Shares are to be issued in satisfaction of Awards granted under this Plan, the Company may
require the Participant to remit to the Company an amount sufficient to satisfy applicable tax withholding requirements prior to the delivery of any certificate or certificates for such Shares. Whenever, under this Plan, payments in satisfaction of
Awards are to be made in cash by the Company, such payment will be net of an amount sufficient to satisfy applicable tax withholding requirements. 

8.2.2 Stock Withholding. When, under applicable tax laws, a Participant incurs tax liability in connection with the exercise or
vesting of any Award that is subject to tax withholding and the Participant is obligated to pay the Company the amount required to be withheld, the Committee may in its sole discretion allow the Participant to satisfy the minimum tax withholding
obligation by electing to have the Company withhold from the Shares to be issued up to the minimum number of Shares having a Fair Market Value on the date that the amount of tax to be withheld is to be determined that is not more than the minimum
amount to be withheld; or to arrange a mandatory “sell to cover” on Participant’s behalf (without further authorization) but in no event will the Company withhold Shares or “sell to cover” if such withholding would result in
adverse accounting consequences to the Company. Any elections to have Shares withheld or sold for this purpose will be made in accordance with the requirements established by the Committee for such elections and be in writing in a form acceptable to
the Committee. 
 9. RESTRICTIONS ON AWARDS. 

9.1 Transferability. Except as permitted by the Committee, Awards granted under this Plan, and any interest therein, will
not be transferable or assignable by Participant, other than by will or by the laws of descent and distribution, and, with respect to NQSOs, by instrument to an inter vivos or testamentary trust in which the NQSOs are to be passed to beneficiaries
upon the death of the trustor (settlor), or by gift to “family member” as that term is defined in Rule 701, and may not be made subject to execution, attachment or similar process. 

  
 8 

 
For the avoidance of doubt, the prohibition against assignment and transfer applies to a stock option and, prior to exercise , the shares to be issued on exercise of a stock option, and pursuant
to the foregoing sentence shall be understood to include, without limitation, a prohibition against any pledge, hypothecation, or other transfer, including any short position, any “put equivalent position” or any “call equivalent
position” (in each case, as defined in Rule 16a-1 promulgated under the Exchange Act). During the lifetime of the Participant an Award will be exercisable only by the Participant or Participant’s legal representative and any elections with
respect to an Award may be made only by the Participant or Participant’s legal representative. The terms of an Option shall be binding upon the executor, administrator, successors and assigns of the Participant who is a party thereto. 

9.2 Securities Law and Other Regulatory Compliance. Although this Plan is intended to be a written compensatory benefit plan
within the meaning of Rule 701 promulgated under the Securities Act, grants may be made pursuant to this Plan that do not qualify for exemption under Rule 701 or Section 25102(o). Any requirement of this Plan which is required in law only
because of Section 25102(o) need not apply with respect to a particular Award to which Section 25102(o) will not apply. An Award will not be effective unless such Award is in compliance with all applicable federal and state securities
laws, rules and regulations of any governmental body, and the requirements of any stock exchange or automated quotation system upon which the Shares may then be listed or quoted, as they are in effect on the date of grant of the Award and also on
the date of exercise or other issuance. Notwithstanding any other provision in this Plan, the Company will have no obligation to issue or deliver certificates for Shares under this Plan prior to (a) obtaining any approvals from governmental
agencies that the Company determines are necessary or advisable, and/or (b) compliance with any exemption, completion of any registration or other qualification of such Shares under any state or federal law or ruling of any governmental body
that the Company determines to be necessary or advisable. The Company will be under no obligation to register the Shares with the SEC or to effect compliance with the exemption, registration, qualification or listing requirements of any state
securities laws, stock exchange or automated quotation system, and the Company will have no liability for any inability or failure so do. 

9.3 Exchange and Buyout of Awards. The Committee may, at any time or from time to time, authorize the Company, with the consent
of the respective Participants, to issue new Awards in exchange for the surrender and cancellation of any or all outstanding Awards. Without prior stockholder approval the Committee may reprice Options or SARs (and where such repricing is a
reduction in the Exercise Price of outstanding Options or SARs, the consent of the affected Participants is not required provided written notice is provided to them). The Committee may at any time buy from a Participant an Award previously granted
with payment in cash, Shares (including Restricted Stock) or other consideration, based on such terms and conditions as the Committee and the Participant may agree. 

10. RESTRICTIONS ON SHARES. 

10.1 Privileges of Stock Ownership. No Participant will have any of the rights of a stockholder with respect to any Shares until
such Shares are issued to the Participant. After Shares are issued to the Participant, the Participant will be a stockholder and have all the rights of a stockholder with respect to such Shares, including the right to vote and receive all

  
 9 

 
dividends or other distributions made or paid with respect to such Shares; provided, that if such Shares are Restricted Stock, then any new, additional or different securities the
Participant may become entitled to receive with respect to such Shares by virtue of a stock dividend, stock split or any other change in the corporate or capital structure of the Company will be subject to the same restrictions as the Restricted
Stock. The Participant will have no right to retain such stock dividends or stock distributions with respect to Unvested Shares that are repurchased as described in this Section 10. 

10.2 Rights of First Refusal and Repurchase. At the discretion of the Committee, the Company may reserve to itself and/or its
assignee(s) in the Award Agreement (a) a right of first refusal to purchase all Shares that a Participant (or a subsequent transferee) may propose to transfer to a third party, provided that such right of first refusal terminates
upon the Company’s initial public offering of Common Stock pursuant to an effective registration statement filed under the Securities Act and (b) a right to repurchase Unvested Shares held by a Participant for cash and/or cancellation of
purchase money indebtedness owed to the Company by the Participant following such Participant’s Termination at any time. 
 10.3
Escrow; Pledge of Shares. To enforce any restrictions on a Participant’s Shares, the Committee may require the Participant to deposit all certificates representing Shares, together with stock powers or other instruments of transfer
approved by the Committee, appropriately endorsed in blank, with the Company or an agent designated by the Company to hold in escrow until such restrictions have lapsed or terminated. The Committee may cause a legend or legends referencing such
restrictions to be placed on the certificate. Any Participant who is permitted to execute a promissory note as partial or full consideration for the purchase of Shares under this Plan will be required to pledge and deposit with the Company all or
part of the Shares so purchased as collateral to secure the payment of Participant’s obligation to the Company under the promissory note; provided, however, that the Committee may require or accept other or
additional forms of collateral to secure the payment of such obligation and, in any event, the Company will have full recourse against the Participant under the promissory note notwithstanding any pledge of the Participant’s Shares or other
collateral. In connection with any pledge of the Shares, Participant will be required to execute and deliver a written pledge agreement in such form as the Committee will from time to time approve. The Shares purchased with the promissory note may
be released from the pledge on a pro rata basis as the promissory note is paid. 
 10.4 Securities Law Restrictions. All
certificates for Shares or other securities delivered under this Plan will be subject to such stock transfer orders, legends and other restrictions as the Committee may deem necessary or advisable, including restrictions under any applicable
federal, state or foreign securities law, or any rules, regulations and other requirements of the SEC or any stock exchange or automated quotation system upon which the Shares may be listed or quoted. 

11. CORPORATE TRANSACTIONS. 

11.1 Acquisitions or Other Combinations. In the event that the Company is subject to an Acquisition or Other Combination,
outstanding Awards acquired under the Plan shall be subject to the agreement evidencing the Acquisition or Other Combination, which need 

  
 10 

 
not treat all outstanding Awards in an identical manner. Such agreement, without the Participant’s consent, shall provide for one or more of the following with respect to all outstanding
Awards as of the effective date of such Acquisition or Other Combination: 
 (a) The continuation of such outstanding Awards by the Company
(if the Company is the successor entity). 
 (b) The assumption of outstanding Awards by the successor or acquiring entity (if any) in such
Acquisition or Other Combination (or by any of its Parents, if any), which assumption, will be binding on all Participants; provided that the exercise price and the number and nature of shares issuable upon exercise of any such option or stock
appreciation right, or any award that is subject to Section 409A of the Code, will be adjusted appropriately pursuant to Section 424(a) and Section 409A of the Code. For the purposes of this Section 11, an Award will be
considered assumed if, following the Acquisition or Other Combination, the Award confers the right to purchase or receive, for each Share subject to the Award immediately prior to the Acquisition or Other Combination, the consideration (whether
stock, cash, or other securities or property) received in the Acquisition or Other Combination by holders of Shares for each Share held on the effective date of the transaction (and if holders were offered a choice of consideration, the type of
consideration chosen by the holders of a majority of the outstanding Shares); provided, however, that if such consideration received in the Acquisition or Other Combination is not solely common stock of the successor corporation or its Parent, the
Committee may, with the consent of the successor corporation, provide for the consideration to be received upon the exercise of an Option or Stock Appreciation Right or upon the payout of a Restricted Stock Unit, for each Share subject to such
Award, to be solely common stock of the successor corporation or its Parent equal in fair market value to the per share consideration received by holders of Common Stock in the Acquisition or Other Combination. 

(c) The substitution by the successor or acquiring entity in such Acquisition or Other Combination (or by any of its Parents, if any) of
equivalent awards with substantially the same terms for such outstanding Awards (except that the exercise price and the number and nature of shares issuable upon exercise of any such option or stock appreciation right, or any award that is subject
to Section 409A of the Code, will be adjusted appropriately pursuant to Section 424(a) of the Code). 
 (d) The full or partial
exercisability or vesting and accelerated expiration of outstanding Awards. 
 (e) The settlement of the full value of such outstanding
Award (whether or not then vested or exercisable) in cash, cash equivalents, or securities of the successor entity (or its Parent, if any) with a Fair Market Value equal to the required amount, followed by the cancellation of such Awards; provided
however, that such Award may be cancelled without consideration if such Award has no value, as determined by the Committee, in its discretion. Subject to Section 409A of the Code, such payment may be made in installments and may be deferred
until the date or dates when the Award would have become exercisable or vested. Such payment may be subject to vesting based on the Participant’s continued service, provided that without the Participant’s consent, the vesting schedule
shall not be less favorable to the Participant than the schedule under which the Award would have become vested or exercisable. For purposes of this Section 11.1(e), the Fair Market Value of any security shall be determined without regard to
any vesting conditions that may apply to such security. 

  
 11 

 (f) The cancellation of outstanding Awards in exchange for no consideration. 

Immediately following an Acquisition or Other Combination, outstanding Awards shall terminate and cease to be outstanding, except to the
extent such Awards, have been continued, assumed or substituted, as described in Sections 11.1(a), (b) and/or (c). 
 11.2
Assumption of Awards by the Company. The Company, from time to time, also may substitute or assume outstanding awards granted by another entity, whether in connection with an acquisition of such other entity or otherwise, by either
(a) granting an Award under this Plan in substitution of such other entity’s award or (b) assuming and/or converting such award as if it had been granted under this Plan if the terms of such assumed award could be applied to an Award
granted under this Plan. Such substitution or assumption will be permissible if the holder of the substituted or assumed award would have been eligible to be granted an Award under this Plan if the other entity had applied the rules of this Plan to
such grant. In the event the Company assumes an award granted by another entity, the terms and conditions of such award will remain unchanged (except that the exercise price and the number and nature of shares issuable upon exercise of any such
option or stock appreciation right, or any award that is subject to Section 409A of the Code, will be adjusted appropriately pursuant to Section 424(a) of the Code). In the event the Company elects to grant a new Option or SAR rather than
assuming an existing option or stock appreciation right, such new Option or SAR may be granted with a similarly adjusted Exercise Price. 

12. ADMINISTRATION. 

12.1 Committee Authority. This Plan will be administered by the Committee or the Board if no Committee is created by the Board.
Subject to the general purposes, terms and conditions of this Plan, and to the direction of the Board, the Committee will have full power to implement and carry out this Plan. Without limitation, the Committee will have the authority to: 

(a) construe and interpret this Plan, any Award Agreement and any other agreement or document executed pursuant to this Plan; 

(b) prescribe, amend, expand, modify and rescind or terminate rules and regulations relating to this Plan; 

(c) approve persons to receive Awards; 

(d) determine the form and terms of Awards; 

(e) determine the number of Shares or other consideration subject to Awards granted under this Plan; 

  
 12 

 (f) determine the Fair Market Value in good faith and interpret the applicable provisions of
this Plan and the definition of Fair Market Value in connection with circumstances that impact the Fair Market Value, if necessary; 
 (g)
determine whether Awards will be granted singly, in combination with, in tandem with, in replacement of, or as alternatives to, other Awards under this Plan or awards under any other incentive or compensation plan of the Company or any Parent or
Subsidiary of the Company; 
 (h) grant waivers of any conditions of this Plan or any Award; 

(i) determine the terms of vesting, exercisability and payment of Awards to be granted pursuant to this Plan; 

(j) correct any defect, supply any omission, or reconcile any inconsistency in this Plan, any Award, any Award Agreement, any Exercise
Agreement or any Restricted Stock Purchase Agreement; 
 (k) determine whether an Award has been earned; 

(l) extend the vesting period beyond a Participant’s Termination Date; 

(m) adopt rules and/or procedures (including the adoption of any subplan under this Plan) relating to the operation and administration of the
Plan to accommodate requirements of local law and procedures outside of the United States; 
 (n) delegate any of the foregoing to a
subcommittee consisting of one or more executive officers pursuant to a specific delegation as may otherwise be permitted by applicable law; 

(o) change the vesting schedule of Awards under the Plan prospectively in the event that the Participant’s service status changes
between full and part time status in accordance with Company policies relating to work schedules and vesting of awards; and 
 (p) make all
other determinations necessary or advisable in connection with the administration of this Plan. 
 12.2 Committee Composition and
Discretion. The Board may delegate full administrative authority over the Plan and Awards to a Committee consisting of at least one member of the Board (or such greater number as may then be required by applicable law). Unless in
contravention of any express terms of this Plan or Award, any determination made by the Committee with respect to any Award will be made in its sole discretion either (a) at the time of grant of the Award, or (b) subject to
Section 4.9 hereof, at any later time. Any such determination will be final and binding on the Company and on all persons having an interest in any Award under this Plan. To the extent permitted by applicable law, the Committee may delegate to
one or more officers of the Company the authority to grant an Award under this Plan, provided that each such officer is a member of the Board. 

  
 13 

 12.3 Nonexclusivity of the Plan. Neither the adoption of this Plan by the Board,
the submission of this Plan to the stockholders of the Company for approval, nor any provision of this Plan will be construed as creating any limitations on the power of the Board to adopt such additional compensation arrangements as it may deem
desirable, including, without limitation, the granting of stock options and other equity awards otherwise than under this Plan, and such arrangements may be either generally applicable or applicable only in specific cases. 

12.4 Governing Law. This Plan and all agreements hereunder shall be governed by and construed in accordance with the laws of the
State of Texas, without giving effect to that body of laws pertaining to conflict of laws. 
 13. EFFECTIVENESS, AMENDMENT AND
TERMINATION OF THE PLAN. 
 13.1 Adoption and Stockholder Approval. This Plan will become effective on the date that it
is adopted by the Board (the “Effective Date”). This Plan will be approved by the stockholders of the Company (excluding Shares issued pursuant to this Plan), consistent with applicable laws, within twelve (12) months
before or after the Effective Date. Upon the Effective Date, the Board may grant Awards pursuant to this Plan; provided, however, that: (a) no Option or SAR may be exercised prior to initial stockholder approval of
this Plan; (b) no Option or SAR granted pursuant to an increase in the number of Shares approved by the Board shall be exercised prior to the time such increase has been approved by the stockholders of the Company; (c) in the event that
initial stockholder approval is not obtained within the time period provided herein, all Awards for which only the exemption from California’s securities qualification requirements provided by Section 25102(o) can apply shall be canceled,
any Shares issued pursuant to any such Award shall be canceled and any purchase of such Shares issued hereunder shall be rescinded; and (d) Awards (to which only the exemption from California’s securities qualification requirements
provided by Section 25102(o) can apply) granted pursuant to an increase in the number of Shares approved by the Board which increase is not approved by stockholders within the time then required under Section 25102(o) shall be canceled,
any Shares issued pursuant to any such Awards shall be canceled, and any purchase of Shares subject to any such Award shall be rescinded. 

13.2 Term of Plan. Unless earlier terminated as provided herein, this Plan will automatically terminate ten (10) years
after the later of (i) the Effective Date, or (ii) the most recent increase in the number of Shares reserved under Section 2 that was approved by stockholders. 

13.3 Amendment or Termination of Plan. Subject to Section 4.9 hereof, the Board may at any time (a) terminate or amend
this Plan in any respect, including without limitation amendment of any form of Award Agreement or instrument to be executed pursuant to this Plan and (b) terminate any and all outstanding Options or SARs upon a dissolution or liquidation of
the Company, followed by the payment of creditors and the distribution of any remaining funds to the Company’s stockholders; provided, however, that the Board will not, without the approval of the stockholders of the
Company, amend this Plan in any manner that requires such stockholder approval pursuant to Section 25102(o) or pursuant to the Code or the regulations promulgated under the Code as such provisions apply to ISO plans. The termination of the
Plan, or any amendment thereof, shall not affect any Share previously issued or any Award previously granted under the Plan. 

  
 14 

 14. DEFINITIONS. For all purposes of this Plan, the following terms will have the
following meanings. 
 “Acquisition,” for purposes of Section 11, means: 

(a) any consolidation or merger in which the Company is a constituent entity or is a party in which the voting stock and other voting
securities of the Company that are outstanding immediately prior to the consummation of such consolidation or merger represent, or are converted into, securities of the surviving entity of such consolidation or merger (or of any Parent of such
surviving entity) that, immediately after the consummation of such consolidation or merger, together possess less than fifty percent (50%) of the total voting power of all voting securities of such surviving entity (or of any of its Parents, if
any) that are outstanding immediately after the consummation of such consolidation or merger; 
 (b) a sale or other transfer by the
holders thereof of outstanding voting stock and/or other voting securities of the Company possessing more than fifty percent (50%) of the total voting power of all outstanding voting securities of the Company, whether in one transaction or in a
series of related transactions, pursuant to an agreement or agreements to which the Company is a party and that has been approved by the Board, and pursuant to which such outstanding voting securities are sold or transferred to a single person or
entity, to one or more persons or entities who are Affiliates of each other, or to one or more persons or entities acting in concert; or 

(c) the sale, lease, transfer or other disposition, in a single transaction or series of related transactions, by the Company and/or any
Subsidiary or Subsidiaries of the Company, of all or substantially all the assets of the Company and its Subsidiaries taken as a whole, (or, if substantially all of the assets of the Company and its Subsidiaries taken as a whole are held by one or
more Subsidiaries, the sale or disposition (whether by consolidation, merger, conversion or otherwise) of such Subsidiaries of the Company), except where such sale, lease, transfer or other disposition is made to the Company or one or more wholly
owned Subsidiaries of the Company (an “Acquisition by Sale of Assets”). 
 “Affiliate” of a
specified person means a person that directly, or indirectly through one or more intermediaries, controls or is controlled by, or is under common control with, the person specified (where, for purposes of this definition, the term
“control” (including the terms controlling, controlled by and under common control with) means the possession, direct or indirect, of the power to direct or cause the direction
of the management and policies of a person, whether through the ownership of voting securities, by contract, or otherwise. 

“Award” means any award pursuant to the terms and conditions of this Plan, including any Option, Restricted Stock
Unit, Stock Appreciation Right or Restricted Stock Award. 
 “Award Agreement” means, with respect to each Award,
the signed written or electronic agreement between the Company and the Participant setting forth the terms and conditions of the Award as approved by the Committee. For purposes of the Plan, the Award Agreement may be executed via written or
electronic means. 

  
 15 

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

“Cause” means Termination because of (a) Participant’s unauthorized misuse of the Company or a Parent or
Subsidiary of the Company’s trade secrets or proprietary information, (b) Participant’s conviction of or plea of nolo contendere to a felony or a crime involving moral turpitude, (c) Participant’s committing an act of fraud
against the Company or a Parent or Subsidiary of the Company or (d) Participant’s gross negligence or willful misconduct in the performance of his or her duties that has had or will have a material adverse effect on the Company or Parent
or Subsidiary of the Company’ reputation or business. 
 “Code” means the Internal Revenue Code of 1986, as
amended. 
 “Committee” means the committee created and appointed by the Board to administer this Plan, or if no
committee is created and appointed, the Board. 
 “Company” means Aeglea BioTherapeutics, Inc., or any successor
corporation. 
 “Disability” means that the Participant is unable to engage in any substantial gainful activity by
reason of any medically determinable physical or mental impairment that can be expected to result in death or can be expected to last for a continuous period of not less than 12 months. 

“Exchange Act” means the Securities Exchange Act of 1934, as amended. 

“Exercise Price” means the price per Share at which a holder of an Option may purchase Shares issuable upon exercise
of the Option. 
 “Fair Market Value” means, as of any date, the value of a share of the Company’s Common Stock
determined as follows: 
 (a) if such Common Stock is then publicly traded on a national securities exchange, its closing price on the date
of determination on the principal national securities exchange on which the Common Stock is listed or admitted to trading as reported in The Wall Street Journal; 

(b) if such Common Stock is publicly traded but is not listed or admitted to trading on a national securities exchange, the average of the
closing bid and asked prices on the date of determination as reported by The Wall Street Journal (or, if not so reported, as otherwise reported by any newspaper or other source as the Committee may determine); or 

(c) if none of the foregoing is applicable to the valuation in question, by the Committee in good faith. 

“Option” means an award of an option to purchase Shares pursuant to Section 4 of this Plan. 

  
 16 

 “Other Combination” for purposes of Section 11 means any
(a) consolidation or merger in which the Company is a constituent entity and is not the surviving entity of such consolidation or merger or (b) any conversion of the Company into another form of entity; provided that such
consolidation, merger or conversion does not constitute an Acquisition. 
 “Parent” of a specified entity means, any
entity that, either directly or indirectly, owns or controls such specified entity, where for this purpose, “control” means the ownership of stock, securities or other interests that possess at least a majority of the voting
power of such specified entity (including indirect ownership or control of such stock, securities or other interests). 

“Participant” means a person who receives an Award under this Plan. 

“Plan” means this 2015 Equity Incentive Plan, as amended from time to time. 

“Purchase Price” means the price at which a Participant may purchase Restricted Stock pursuant to this Plan. 

“Restricted Stock” means Shares purchased pursuant to a Restricted Stock Award under this Plan. 

“Restricted Stock Award” means an award of Shares pursuant to Section 5 hereof. 

“Restricted Stock Unit” or “RSU” means an award made pursuant to Section 6 hereof. 

“Rule 701” means Rule 701 et seq. promulgated by the Commission under the Securities Act. 

“SEC” means the Securities and Exchange Commission. 

“Section 25102(o)” means Section 25102(o) of the California Corporations Code. 

“Securities Act” means the Securities Act of 1933, as amended. 

“Shares” means shares of the Company’s Common Stock reserved for issuance under this Plan, as adjusted pursuant
to Sections 2.2 and 11 hereof, and any successor security. 
 “Stock Appreciation Right” or
“SAR” means an award granted pursuant to Section 7 hereof. 
 “Subsidiary” means any
entity (other than the Company) in an unbroken chain of entities beginning with the Company if each of the entities other than the last entity in the unbroken chain owns stock or other equity securities representing fifty percent (50%) or more
of the total combined voting power of all classes of stock or other equity securities in one of the other entities in such chain. 

  
 17 

 “Termination” or “Terminated” means, for purposes
of this Plan with respect to a Participant, that the Participant has for any reason ceased to provide services as an employee, officer, director or consultant to the Company or a Parent or Subsidiary of the Company. A Participant will not be deemed
to have ceased to provide services while the Participant is on a bona fide leave of absence, if such leave was approved by the Company in writing. In the case of an approved leave of absence, the Committee may make such provisions respecting
crediting of service, including suspension of vesting of the Award (including pursuant to a formal policy adopted from time to time by the Company) it may deem appropriate, except that in no event may an Option be exercised after the expiration of
the term set forth in the Stock Option Agreement. The Committee will have sole discretion to determine whether a Participant has ceased to provide services and the effective date on which the Participant ceased to provide services (the
“Termination Date”). 
 “Unvested Shares” means “Unvested Shares” as
defined in the Award Agreement for an Award. 
 “Vested Shares” means “Vested Shares” as
defined in the Award Agreement. 
 * * * * * * * * * * * 

  
 18 

 OPTION GRANT NO.      

NOTICE OF STOCK OPTION GRANT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

The Optionee named below (“Optionee”) has been granted an option (this “Option”) to purchase shares of Common
Stock, $0.001 par value per share (the “Common Stock”), of Aeglea BioTherapeutics, Inc., a Delaware corporation (the “Company”), pursuant to the Company’s 2015 Equity Incentive Plan, as amended
from time to time (the “Plan”) on the terms, and subject to the conditions, described below and in the Stock Option Agreement attached hereto as Exhibit A, including its annexes (the “Stock
Option Agreement”). 
  

			
	Optionee:		
		
	Maximum Number of Shares Subject to this Option (the “Shares”):		
		
	Exercise Price Per Share:		$         per share
		
	Date of Grant:		
		
	Vesting Start Date:		
		
	Exercise Schedule:		This Option will become exercisable during its term with respect to portions of the Shares in accordance with the Vesting Schedule set forth below.
		
	Expiration Date:		The date ten (10) years after the Date of Grant set forth above, subject to earlier expiration in the event of Termination as provided in Section 3 of the Stock Option Agreement.
		
	 Tax Status of Option:
 (Check
Only One Box):
		  ̈ Incentive Stock Option (To the fullest extent permitted by the Code)

 ̈ Nonqualified Stock Option.

(If neither box is checked, this Option is a Nonqualified Stock Option).

			

 Vesting Schedule [EXAMPLE ONLY]: For so long as Optionee continuously provides services to the Company (or any
Subsidiary or Parent of the Company) as an employee, officer, director, contractor or consultant, this Option will vest (that is, become exercisable) with respect to the Shares as follows: (a) prior to the first one (1) year anniversary of
the Vesting Start Date this Option will not be vested or exercisable as to any of the Shares; (b) this Option will become vested and exercisable with respect to [1/4th] of the Shares
on the one (1) year anniversary of the Vesting Start Date; and (c) thereafter, this Option will become vested and exercisable with respect to an additional [1/48th] of the Shares
when Optionee completes each month of continuous service following the first one (1) year anniversary of the Vesting Start Date. 
 General;
Agreement: By their signatures below, Optionee and the Company agree that this Option is granted under and governed by this Notice of Stock Option Grant (this “Grant Notice”) and by the provisions of the Plan and the
Stock Option Agreement. The Plan and the Stock Option Agreement are incorporated herein by reference. Capitalized terms used but not defined herein shall have the meanings given to them in the Plan or in the Stock Option Agreement, as applicable. By
signing below, Optionee acknowledges receipt of a copy of this Grant Notice, the Plan and the Stock Option Agreement, represents that Optionee has carefully read and is familiar with their provisions, and hereby accepts the Option subject to all of
their respective terms and conditions. Optionee acknowledges that there may be adverse tax consequences upon exercise of the Option or disposition of the Shares and that Optionee should consult a tax adviser prior to such exercise or disposition.

 Execution and Delivery: This Grant Notice may be executed and delivered electronically whether via the Company’s intranet or the Internet
site of a third party or via email or any other means of electronic delivery specified by the Company. By Optionee’s acceptance hereof (whether written, electronic or otherwise), Optionee agrees, to the fullest extent permitted by law, that in
lieu of receiving documents in paper format, Optionee accepts the electronic delivery of any documents that the Company (or any third party the Company may designate), may deliver in connection with this grant (including the Plan, this Grant Notice,
the Stock Option Agreement, the information described in Rules 701(e)(2), (3), (4) and (5) under the Securities Act (the “701 Disclosures”), account statements, or other communications or information) whether via
the Company’s intranet or the Internet site of such third party or via email or such other means of electronic delivery specified by the Company. 

Aeglea BioTherapeutics, Inc. 
  

									
	By /Signature:		  
				Optionee Signature:		  

	Typed Name:		  
				Optionee’s Name:		  

	Title:		  
						

 ATTACHMENT: Exhibit A - Stock Option Agreement 

 Exhibit A 

Stock Option Agreement 

 EXHIBIT A 

STOCK OPTION AGREEMENT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

This Stock Option Agreement (this “Agreement”) is made and entered into as of the date of grant (the “Date
of Grant”) set forth on the Notice of Stock Option Grant attached as the facing page to this Agreement (the “Grant Notice”) by and between Aeglea BioTherapeutics, Inc., a Delaware corporation (the
“Company”), and the optionee named on the Grant Notice (“Optionee”). Capitalized terms not defined in this Agreement shall have the meaning ascribed to them in the Company’s 2015 Equity Incentive
Plan, as amended from time to time (the “Plan”), or in the Grant Notice, as applicable. 
 1. GRANT OF OPTION.
The Company hereby grants to Optionee an option (this “Option”) to purchase up to the total number of shares of Common Stock of the Company, $0.001 par value per share (the “Common Stock”), set
forth in the Grant Notice as the Shares (the “Shares”) at the Exercise Price Per Share set forth in the Grant Notice (the “Exercise Price”), subject to all of the terms and conditions of the Grant
Notice, this Agreement and the Plan. If designated as an Incentive Stock Option in the Grant Notice, this Option is intended to qualify as an incentive stock option (the “ISO”) within the meaning of Section 422 of the
Internal Revenue Code of 1986, as amended (the “Code”), except that if on the Date of Grant Optionee is not subject to U.S. income tax, then this Option shall be a NQSO. 

2. EXERCISE PERIOD. 

2.1 Exercise Period of Option. This Option is considered to be “vested” with respect to any particular Shares when this
Option is exercisable with respect to such Shares. This Option will become vested during its term as to portions of the Shares in accordance with the Vesting Schedule set forth in the Grant Notice. Notwithstanding any provision in the Plan or this
Agreement to the contrary, on or after Optionee’s Termination Date, this Option may not be exercised with respect to any Shares that are Unvested Shares on Optionee’s Termination Date. 

2.2 Vesting of Option Shares. Shares with respect to which this Option is vested and exercisable at a given time pursuant to the
Vesting Schedule set forth in the Grant Notice are “Vested Shares.” Shares with respect to which this Option is not vested and exercisable at a given time pursuant to the Vesting Schedule set forth in the Grant Notice
are “Unvested Shares.” 
 2.3 Expiration. The Option shall expire on the Expiration Date
set forth in the Grant Notice or earlier as provided in Section 3 below. 
 3. TERMINATION. 

3.1 Termination for Any Reason Except Death, Disability or Cause. Except as provided in subsection 3.2 in a case in which
Optionee dies within three (3) months after Optionee is Terminated other than for Cause, if Optionee is Terminated for any reason (other than Optionee’s death or Disability or for Cause), then (a) on and after Optionee’s
Termination Date, this Option shall expire immediately with respect to any Shares that are Unvested Shares and may not be exercised with respect to any Shares that are Unvested Shares on Optionee’s Termination Date and (b) this Option to
the extent (and only to the extent) that it is exercisable with respect to Vested Shares on Optionee’s Termination Date, may be exercised by Optionee no later than three (3) months after Optionee’s Termination Date (but in no event
may this Option be exercised after the Expiration Date). 
 3.2 Termination Because of Death or Disability. If Optionee is
Terminated because of Optionee’s death or Disability (or if Optionee dies within three (3) months of the date of 

 
Optionee’s Termination for any reason other than for Cause), then (a) on and after Optionee’s Termination Date, this Option shall expire immediately with respect to any Shares that
are Unvested Shares and may not be exercised with respect to any Shares that are Unvested Shares on Optionee’s Termination Date and (b) this Option, to the extent (and only to the extent) that it is exercisable with respect to Vested
Shares on Optionee’s Termination Date, may be exercised by Optionee (or Optionee’s legal representative) no later than twelve (12) months after Optionee’s Termination Date, but in no event later than the Expiration Date. Any
exercise of this Option beyond (i) three (3) months after the date Optionee ceases to be an employee when Optionee’s Termination is for any reason other than Optionee’s death or disability, within the meaning of
Section 22(e)(3) of the Code; or (ii) twelve (12) months after the date Optionee ceases to be an employee when the termination is for Optionee’s disability, within the meaning of Section 22(e)(3) of the Code, is deemed to be
an NQSO. 
 3.3 Termination for Cause. If Optionee is Terminated for Cause, then Optionee may exercise this Option, but only
with respect to any Shares that are Vested Shares on Optionee’s Termination Date, and this Option shall expire on Optionee’s Termination Date, or at such later time and on such conditions as may be affirmatively determined by the
Committee. On and after Optionee’s Termination Date, this Option shall expire immediately with respect to any Shares that are Unvested Shares and may not be exercised with respect to any Shares that are Unvested Shares on Optionee’s
Termination Date. 
 3.4 No Obligation to Employ. Nothing in the Plan or this Agreement shall confer on Optionee any right to
continue in the employ of, or other relationship with, the Company or any Parent or Subsidiary of the Company, or limit in any way the right of the Company or any Parent or Subsidiary of the Company to terminate Optionee’s employment or other
relationship at any time, with or without Cause. 
 4. MANNER OF EXERCISE. 

4.1 Stock Option Exercise Notice and Agreement. To exercise this Option, Optionee (or in the case of exercise after
Optionee’s death or incapacity, Optionee’s executor, administrator, heir or legatee, as the case may be) must deliver to the Company an executed Stock Option Exercise Notice and Agreement in the form attached hereto as
Annex A, or in such other form as may be approved by the Committee from time to time (the “Exercise Agreement”) and payment for the shares being purchased in accordance with this Agreement. The Exercise
Agreement shall set forth, among other things, (i) Optionee’s election to exercise this Option, (ii) the number of Shares being purchased, (iii) any representations, warranties and agreements regarding Optionee’s investment
intent and access to information as may be required by the Company to comply with applicable securities laws in connection with any exercise of this Option and (iv) any other agreements required by the Company. If someone other than Optionee
exercises this Option, then such person must submit documentation reasonably acceptable to the Company verifying that such person has the legal right to exercise this Option and such person shall be subject to all of the restrictions contained
herein as if such person were Optionee. 
 4.2 Limitations on Exercise. This Option may not be exercised unless such exercise
is in compliance with all applicable federal and state securities laws, as they are in effect on the date of exercise. 
 4.3
Payment. The Exercise Agreement shall be accompanied by full payment of the Exercise Price for the shares being purchased in cash (by check or wire transfer), or where permitted by law: 

(a) by cancellation of indebtedness of the Company owed to Optionee; 

(b) by surrender of shares of the Company that are free and clear of all security interests, pledges, liens, claims or encumbrances and:
(i) for which the Company has received 

  
 2 

 
“full payment of the purchase price” within the meaning of SEC Rule 144 (and, if such shares were purchased from the Company by use of a promissory note, such note has been fully
paid with respect to such shares) or (ii) that were obtained by Optionee in the public market; 
 (c) by participating in a formal
cashless exercise program implemented by the Committee in connection with the Plan; 
 (d) provided that a public market for the Common
Stock exists and subject to compliance with applicable law, by exercising as set forth below, through a “same day sale” commitment from Optionee and a broker-dealer whereby Optionee irrevocably elects to exercise this Option and to sell a
portion of the Shares so purchased sufficient to pay the total Exercise Price, and whereby the broker-dealer irrevocably commits upon receipt of such Shares to forward the total Exercise Price directly to the Company; or 

(e) by any combination of the foregoing or any other method of payment approved by the Committee that constitutes legal consideration for the
issuance of Shares. 
 4.4 Tax Withholding. Prior to the issuance of the Shares upon exercise of the Option, Optionee must pay
or provide for any applicable federal, state and local withholding obligations of the Company. If the Committee permits, Optionee may provide for payment of withholding taxes upon exercise of the Option by requesting that the Company retain the
minimum number of Shares with a Fair Market Value equal to the minimum amount of taxes required to be withheld; or to arrange a mandatory “sell to cover” on Participant’s behalf (without further authorization); but in no event will
the Company withhold Shares or “sell to cover” if such withholding would result in adverse accounting consequences to the Company. In case of stock withholding or a sell to cover, the Company shall issue the net number of Shares to
Optionee by deducting the Shares retained from the Shares issuable upon exercise. 
 4.5 Issuance of Shares. Provided that the
Exercise Agreement and payment are in form and substance satisfactory to counsel for the Company, the Company shall issue the Shares issuable upon a valid exercise of this Option registered in the name of Optionee, Optionee’s authorized
assignee, or Optionee’s legal representative, and shall deliver certificates representing the Shares with the appropriate legends affixed thereto. 

5. COMPLIANCE WITH LAWS AND REGULATIONS. The Plan and this Agreement are intended to comply with
Section 25102(o) and Rule 701. Any provision of this Agreement that is inconsistent with Section 25102(o) or Rule 701 shall, without further act or amendment by the Company or the Committee, be reformed to comply with the requirements of
Section 25102(o) and/or Rule 701. The exercise of this Option and the issuance and transfer of Shares shall be subject to compliance by the Company and Optionee with all applicable requirements of federal and state securities laws and with all
applicable requirements of any stock exchange on which the Common Stock may be listed at the time of such issuance or transfer. Optionee understands that the Company is under no obligation to register or qualify the Shares with the SEC, any state
securities commission or any stock exchange to effect such compliance. 
 6. NONTRANSFERABILITY OF OPTION. This Option may
not be transferred in any manner other than by will or by the laws of descent and distribution, and, with respect to NQSOs, by instrument to a testamentary trust in which the options are to be passed to beneficiaries upon the death of the trustor
(settlor) or a revocable trust, or by gift to “immediate family” as that term is defined in 17 C.F.R. 240.16a-1(e), and may be exercised during the lifetime of Optionee only by Optionee or in the event of Optionee’s incapacity, by
Optionee’s legal representative. The terms of this Option shall be binding upon the executors, administrators, successors and assigns of Optionee. 

  
 3 

 7. RESTRICTIONS ON TRANSFER. 

7.1 Disposition of Shares. Optionee hereby agrees that Optionee shall make no disposition of any of the Shares (other than
as permitted by this Agreement) unless and until: 
 (a) Optionee shall have notified the Company of the proposed disposition and provided
a written summary of the terms and conditions of the proposed disposition; 
 (b) Optionee shall have complied with all requirements of
this Agreement applicable to the disposition of the Shares; 
 (c) Optionee shall have provided the Company with written assurances, in
form and substance satisfactory to counsel for the Company, that (i) the proposed disposition does not require registration of the Shares under the Securities Act or under any applicable state securities laws or (ii) all appropriate
actions necessary for compliance with the registration requirements of the Securities Act or of any exemption from registration available under the Securities Act (including Rule 144) or applicable state securities laws have been taken; and 

(d) Optionee shall have provided the Company with written assurances, in form and substance satisfactory to the Company, that the proposed
disposition will not result in the contravention of any transfer restrictions applicable to the Shares pursuant to the provisions of the regulations promulgated under Section 25102(o), Rule 701 or under any other applicable securities laws or
adversely affect the Company’s ability to rely on the exemption(s) from registration under the Securities Act or under any other applicable securities laws for the grant of the Option, the issuance of Shares thereunder or any other issuance of
securities under the Plan. 
 7.2 Restriction on Transfer. Optionee shall not transfer, assign, grant a lien or security
interest in, pledge, hypothecate, encumber or otherwise dispose of any of the Shares which are subject to the Company’s Right of First Refusal described below, except as permitted by this Agreement. 

7.3 Transferee Obligations. Each person (other than the Company) to whom the Shares are transferred by means of one of the
permitted transfers specified in this Agreement must, as a condition precedent to the validity of such transfer, acknowledge in writing to the Company that such person is bound by the provisions of this Agreement and that the transferred Shares are
subject to (i) the Company’s Right of First Refusal granted hereunder and (ii) the market stand-off provisions of Section 8 below, to the same extent such Shares would be so subject if retained by Optionee. 

8. MARKET STANDOFF AGREEMENT. Optionee agrees that, subject to any early release provisions that apply pro rata to stockholders of the
Company according to their holdings of Common Stock (determined on an as-converted into Common Stock basis), Optionee will not, for a period of up to one hundred eighty (180) days (plus up to an additional thirty five (35) days to the
extent reasonably requested by the Company or such underwriter(s) to accommodate regulatory restrictions on the publication or other distribution of research reports or earnings releases by the Company, including NASD and NYSE rules) following the
effective date of the registration statement filed with the SEC relating to the initial underwritten sale of Common Stock of the Company to the public under the Securities Act (the “IPO”), directly or indirectly sell, offer
to sell, grant any option for the sale of, or otherwise dispose of any Common Stock or securities convertible into Common Stock, except for: (i) transfers of Shares permitted under Section 9.6 hereof so long as such
transferee furnishes to the Company and the managing underwriter their written consent to be bound by this Section 8 as a condition precedent to such transfer; and (ii) sales of any securities to be included in the registration statement
for the IPO. For the avoidance of doubt, the provisions of this Section shall only apply to the IPO. The restricted period shall in any event terminate two (2) years after the closing date of the IPO. In order to enforce the foregoing covenant,
the Company shall have the right to place restrictive legends on the certificates representing the Shares subject to this Section and to impose stop transfer instructions with 

  
 4 

 
respect to the Shares until the end of such period. Optionee further agrees to enter into any agreement reasonably required by the underwriters to implement the foregoing restrictions on
transfer. For the avoidance of doubt, the foregoing provisions of this Section shall not apply to any registration of securities of the Company (a) under an employee benefit plan or (b) in a merger, consolidation, business combination or
similar transaction. 
 9. COMPANY’S RIGHT OF FIRST REFUSAL. Before any Shares held by Optionee or any transferee of such Shares
(either sometimes referred to herein as the “Holder”) may be sold or otherwise transferred (including, without limitation, a transfer by gift or operation of law), the Company and/or its assignee(s) will have a
right of first refusal to purchase the Shares to be sold or transferred (the “Offered Shares”) on the terms and conditions set forth in this Section (the “Right of First
Refusal”). 
 9.1 Notice of Proposed Transfer. The Holder of the Offered Shares will deliver
to the Company a written notice (the “Notice”) stating: (i) the Holder’s bona fide intention to sell or otherwise transfer the Offered Shares; (ii) the name and address of each proposed purchaser or other
transferee (the “Proposed Transferee”); (iii) the number of Offered Shares to be transferred to each Proposed Transferee; (iv) the bona fide cash price or other consideration for which the Holder proposes to
transfer the Offered Shares (the “Offered Price”); and (v) that the Holder acknowledges this Notice is an offer to sell the Offered Shares to the Company and/or its assignee(s) pursuant to the Company’s Right of
First Refusal at the Offered Price as provided for in this Agreement. 
 9.2 Exercise of Right of First Refusal. At any
time within thirty (30) days after the date of the Notice, the Company and/or its assignee(s) may, by giving written notice to the Holder, elect to purchase all (or, with the consent of the Holder, less than all) the Offered Shares proposed to
be transferred to any one or more of the Proposed Transferees named in the Notice, at the purchase price, determined as specified below. 

9.3 Purchase Price. The purchase price for the Offered Shares purchased under this Section will be the Offered Price,
provided that if the Offered Price consists of no legal consideration (as, for example, in the case of a transfer by gift) then the purchase price will be the fair market value of the Offered Shares as determined in good faith by the
Committee. If the Offered Price includes consideration other than cash, then the value of the non-cash consideration, as determined in good faith by the Committee, will conclusively be deemed to be the cash equivalent value of such non-cash
consideration. 
 9.4 Payment. Payment of the purchase price for the Offered Shares will be payable, at the option of the
Company and/or its assignee(s) (as applicable), by check or by cancellation of all or a portion of any outstanding purchase money indebtedness owed by the Holder to the Company (or to such assignee, in the case of a purchase of Offered Shares by
such assignee) or by any combination thereof. The purchase price will be paid without interest within sixty (60) days after the Company’s receipt of the Notice, or, at the option of the Company and/or its assignee(s), in the manner and at
the time(s) set forth in the Notice. 
 9.5 Holder’s Right to Transfer. If all of the Offered Shares proposed in the
Notice to be transferred to a given Proposed Transferee are not purchased by the Company and/or its assignee(s) as provided in this Section, then the Holder may sell or otherwise transfer such Offered Shares to each Proposed Transferee at the
Offered Price or at a higher price, provided that (i) such sale or other transfer is consummated within ninety (90) days after the date of the Notice, (ii) any such sale or other transfer is effected in compliance with
all applicable securities laws, and (iii) each Proposed Transferee agrees in writing that the provisions of this Section will continue to apply to the Offered Shares in the hands of such Proposed Transferee. If the Offered Shares described in
the Notice are not transferred to each Proposed Transferee within such ninety (90) day period, then a new Notice must be given to the Company pursuant to which the Company will again be offered the Right of First Refusal before any Shares held
by the Holder may be sold or otherwise transferred. 

  
 5 

 9.6 Exempt Transfers. Notwithstanding anything to the contrary in this Section, the
following transfers of Shares will be exempt from the Right of First Refusal: (i) the transfer of any or all of the Shares during Optionee’s lifetime by gift or on Optionee’s death by will or intestacy to any member(s) of
Optionee’s “Immediate Family” (as defined below) or to a trust for the benefit of Optionee and/or member(s) of Optionee’s Immediate Family, provided that each transferee or other recipient agrees in a writing
satisfactory to the Company that the provisions of this Section will continue to apply to the transferred Shares in the hands of such transferee or other recipient; (ii) any transfer of Shares made pursuant to a statutory merger, statutory
consolidation of the Company with or into another corporation or corporations or a conversion of the Company into another form of legal entity (except that the Right of First Refusal will continue to apply thereafter to such Shares, in which case
the surviving corporation of such merger or consolidation or the resulting entity of such conversion shall succeed to the rights of the Company under this Section unless the agreement of merger or consolidation or conversion expressly otherwise
provides); or (iii) any transfer of Shares pursuant to the winding up and dissolution of the Company. As used herein, the term “Immediate Family” will mean Optionee’s spouse, the lineal descendant or antecedent,
father, mother, brother or sister, child, adopted child, grandchild or adopted grandchild of Optionee or Optionee’s spouse, or the spouse of any of the above or Spousal Equivalent, as defined herein. As used herein, a person is deemed to be a
“Spousal Equivalent” provided the following circumstances are true: (i) irrespective of whether or not Optionee and the Spousal Equivalent are the same sex, they are the sole spousal equivalent of the other for the last
twelve (12) months, (ii) they intend to remain so indefinitely, (iii) neither are married to anyone else, (iv) both are at least 18 years of age and mentally competent to consent to contract, (v) they are not related by
blood to a degree of closeness that which would prohibit legal marriage in the state in which they legally reside, (vi) they are jointly responsible for each other’s common welfare and financial obligations, and (vii) they reside
together in the same residence for the last twelve (12) months and intend to do so indefinitely. 
 9.7 Termination of Right of
First Refusal. The Right of First Refusal will terminate as to all Shares: (i) on the effective date of the first sale of Common Stock of the Company to the general public pursuant to a registration statement filed with and
declared effective by the SEC under the Securities Act (other than a registration statement relating solely to the issuance of Common Stock pursuant to a business combination or an employee incentive or benefit plan); (ii) on any transfer or
conversion of Shares made pursuant to a statutory merger or statutory consolidation of the Company with or into another corporation or corporations if the common stock of the surviving corporation or any direct or indirect parent corporation thereof
is registered under the Exchange Act; or (iii) on any transfer or conversion of Shares made pursuant to a statutory conversion of the Company into another form of legal entity if the common equity (or comparable equity security) of entity
resulting from such conversion is registered under the Exchange Act. 
 9.8 Encumbrances on Shares. Optionee may grant a lien
or security interest in, or pledge, hypothecate or encumber Shares only if each party to whom such lien or security interest is granted, or to whom such pledge, hypothecation or other encumbrance is made, agrees in a writing satisfactory to the
Company that: (i) such lien, security interest, pledge, hypothecation or encumbrance will not adversely affect or impair the Right of First Refusal or the rights of the Company and/or its assignee(s) with respect thereto and will not apply to
such Shares after they are acquired by the Company and/or its assignees under this Section; and (ii) the provisions of this Agreement will continue to apply to such Shares in the hands of such party and any transferee of such party. 

10. RIGHTS AS A STOCKHOLDER. Optionee shall not have any of the rights of a stockholder with respect to any Shares unless and until
such Shares are issued to Optionee. Subject to the terms and conditions of this Agreement, Optionee will have all of the rights of a stockholder of the Company with respect to the Shares from and after the date that Shares are issued to Optionee
pursuant to, and in accordance with, the terms of the Exercise Agreement until such time as Optionee disposes of the Shares or the Company and/or its assignee(s) exercise(s) the Right of First Refusal. Upon an exercise of the Right of First Refusal,
Optionee will have no further rights as a holder of the Shares so purchased upon such exercise, other than the right to receive payment for the Shares so purchased in accordance with the provisions of this Agreement, and Optionee will promptly
surrender the stock certificate(s) evidencing the Shares so purchased to the Company for transfer or cancellation. 

  
 6 

 11. ESCROW. As security for Optionee’s faithful
performance of this Agreement, Optionee agrees, immediately upon receipt of the stock certificate(s) evidencing the Shares, to deliver such certificate(s) to the Secretary of the Company or other designee of the Company (the “Escrow
Holder”), who is hereby appointed to hold such certificate(s) in escrow and to take all such actions and to effectuate all such transfers and/or releases of such Shares as are in accordance with the terms of this Agreement. Optionee and
the Company agree that Escrow Holder will not be liable to any party to this Agreement (or to any other party) for any actions or omissions unless Escrow Holder is grossly negligent or intentionally fraudulent in carrying out the duties of Escrow
Holder under this Agreement. Escrow Holder may rely upon any letter, notice or other document executed with any signature purported to be genuine and may rely on the advice of counsel and obey any order of any court with respect to the transactions
contemplated by this Agreement and will not be liable for any act or omission taken by Escrow Holder in good faith reliance on such documents, the advice of counsel or a court order. The Shares will be released from escrow upon termination of the
Right of First Refusal.  
 12. RESTRICTIVE LEGENDS AND STOP-TRANSFER ORDERS. 

12.1 Legends. Optionee understands and agrees that the Company will place the legends set forth below or similar legends on any
stock certificate(s) evidencing the Shares, together with any other legends that may be required by state or U.S. Federal securities laws, the Company’s Certificate of Incorporation or Bylaws, any other agreement between Optionee and the
Company, or any agreement between Optionee and any third party (and any other legend(s) that the Company may become obligated to place on the stock certificate(s) evidencing the Shares under the terms of any agreement to which the Company is or may
become bound or obligated): 
 (a) THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED
(THE “SECURITIES ACT”), OR UNDER THE SECURITIES LAWS OF CERTAIN STATES. THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS PERMITTED UNDER THE SECURITIES ACT AND
APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM. INVESTORS SHOULD BE AWARE THAT THEY MAY BE REQUIRED TO BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN INDEFINITE PERIOD OF TIME. THE ISSUER OF THESE SECURITIES
MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS. 

(b) THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RESTRICTIONS ON RESALE AND TRANSFER, INCLUDING THE RIGHT OF FIRST
REFUSAL HELD BY THE ISSUER AND/OR ITS ASSIGNEE(S) AS SET FORTH IN A STOCK OPTION AGREEMENT BETWEEN THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE ISSUER. SUCH SALE AND TRANSFER
RESTRICTIONS, INCLUDING THE RIGHT OF FIRST REFUSAL, ARE BINDING ON TRANSFEREES OF THESE SHARES. 
 (c) THE SHARES REPRESENTED BY THIS
CERTIFICATE ARE SUBJECT TO A MARKET STANDOFF RESTRICTION AS SET FORTH IN A CERTAIN STOCK OPTION AGREEMENT BETWEEN THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE ISSUER. AS A RESULT
OF SUCH AGREEMENT, THESE SHARES MAY NOT BE TRADED PRIOR TO 180 DAYS AFTER THE EFFECTIVE DATE OF CERTAIN PUBLIC OFFERINGS OF THE COMMON STOCK OF THE ISSUER HEREOF. SUCH RESTRICTION IS BINDING ON TRANSFEREES OF THESE SHARES. 

  
 7 

 12.2 Stop-Transfer Instructions. Optionee agrees that, to ensure compliance with
the restrictions imposed by this Agreement, the Company may issue appropriate “stop-transfer” instructions to its transfer agent, if any, and if the Company transfers its own securities, it may make appropriate notations to the same effect
in its own records. 
 12.3 Refusal to Transfer. The Company will not be required (i) to transfer on its books any Shares
that have been sold or otherwise transferred in violation of any of the provisions of this Agreement or (ii) to treat as owner of such Shares, or to accord the right to vote or pay dividends to any purchaser or other transferee to whom such
Shares have been so transferred. 
 13. CERTAIN TAX CONSEQUENCES. Set forth below is a brief summary as of the Effective Date of the
Plan of some of the federal tax consequences of exercise of the Option and disposition of the Shares. THIS SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. OPTIONEE SHOULD CONSULT A TAX ADVISER BEFORE
EXERCISING THE OPTION OR DISPOSING OF THE SHARES. 
 13.1 Exercise of ISO. If the Option qualifies as an ISO, there will be no
regular federal income tax liability upon the exercise of the Option, although the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the Exercise Price will be treated as a tax preference item for federal
alternative minimum tax purposes and may subject Optionee to the alternative minimum tax in the year of exercise. 
 13.2 Exercise of
Nonqualified Stock Option. If the Option does not qualify as an ISO, there may be a regular federal income tax liability upon the exercise of the Option. Optionee will be treated as having received compensation income (taxable at ordinary
income tax rates) equal to the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the Exercise Price. If Optionee is a current or former employee of the Company, the Company may be required to withhold from
Optionee’s compensation or collect from Optionee and pay to the applicable taxing authorities an amount equal to a percentage of this compensation income at the time of exercise. 

13.3 Disposition of Shares. The following tax consequences may apply upon disposition of the Shares. 

(a) Incentive Stock Options. If the Shares are held for more than twelve (12) months after the date of purchase of the Shares
pursuant to the exercise of an ISO and are disposed of more than two (2) years after the Date of Grant, any gain realized on disposition of the Shares will be treated as long term capital gain for federal income tax purposes. If Shares
purchased under an ISO are disposed of within the applicable one (1) year or two (2) year period, any gain realized on such disposition will be treated as compensation income (taxable at ordinary income rates in the year of the
disposition) to the extent of the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the Exercise Price. 

(b) Nonqualified Stock Options. If the Shares are held for more than twelve (12) months after the date of purchase of the Shares
pursuant to the exercise of an NQSO, any gain realized on disposition of the Shares will be treated as long term capital gain. 
 14.
GENERAL PROVISIONS. 
 14.1 Interpretation. Any dispute regarding the interpretation of this Agreement shall be submitted
by Optionee or the Company to the Committee for review. The resolution of such a dispute by the Committee shall be final and binding on the Company and Optionee. 

  
 8 

 14.2 Entire Agreement. The Plan, the Grant Notice and the Exercise Agreement are
each incorporated herein by reference. This Agreement, the Grant Notice, the Plan and the Exercise Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede all prior undertakings and agreements
with respect to such subject matter. 
 15. NOTICES. Any and all notices required or permitted to be given to a party pursuant to the
provisions of this Agreement will be in writing and will be effective and deemed to provide such party sufficient notice under this Agreement on the earliest of the following: (i) at the time of personal delivery, if delivery is in person;
(ii) at the time an electronic confirmation of receipt is received, if delivery is by email; (iii) at the time of transmission by facsimile, addressed to the other party at its facsimile number specified herein (or hereafter modified by
subsequent notice to the parties hereto), with confirmation of receipt made by both telephone and printed confirmation sheet verifying successful transmission of the facsimile; (iv) one (1) business day after deposit with an express
overnight courier for United States deliveries, or two (2) business days after such deposit for deliveries outside of the United States, with proof of delivery from the courier requested; or (v) three (3) business days after deposit
in the United States mail by certified mail (return receipt requested) for United States deliveries. Any notice for delivery outside the United States will be sent by email, facsimile or by express courier. Any notice not delivered personally or by
email will be sent with postage and/or other charges prepaid and properly addressed to Optionee at the last known address or facsimile number on the books of the Company, or at such other address or facsimile number as such other party may designate
by one of the indicated means of notice herein to the other parties hereto or, in the case of the Company, to it at its principal place of business. Notices to the Company will be marked “Attention: Chief Financial Officer.” Notices by
facsimile shall be machine verified as received. 
 16. SUCCESSORS AND ASSIGNS. The Company may assign any of its rights under this
Agreement including its rights to purchase Shares under the Right of First Refusal. This Agreement shall be binding upon and inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer set forth herein,
this Agreement shall be binding upon Optionee and Optionee’s heirs, executors, administrators, legal representatives, successors and assigns. 

17. GOVERNING LAW. This Agreement shall be governed by and construed in accordance with the internal laws of the State of California as
such laws are applied to agreements between California residents entered into and to be performed entirely within California. If any provision of this Agreement is determined by a court of law to be illegal or unenforceable, then such provision will
be enforced to the maximum extent possible and the other provisions will remain fully effective and enforceable. 
 18. FURTHER
ASSURANCES. The parties agree to execute such further documents and instruments and to take such further actions as may be reasonably necessary to carry out the purposes and intent of this Agreement. 

19. TITLES AND HEADINGS. The titles, captions and headings of this Agreement are included for ease of reference only and will be
disregarded in interpreting or construing this Agreement. Unless otherwise specifically stated, all references herein to “sections” and “exhibits” will mean “sections” and “exhibits” to this Agreement. 

20. COUNTERPARTS. This Agreement may be executed in any number of counterparts, each of which when so executed and delivered will be
deemed an original, and all of which together shall constitute one and the same agreement. 
 21. SEVERABILITY. If any provision of
this Agreement is determined by any court or arbitrator of competent jurisdiction to be invalid, illegal or unenforceable in any respect, such provision will be enforced to the maximum extent possible given the intent of the parties hereto. If such
clause or provision cannot be so enforced, such provision shall be stricken from this Agreement and the remainder 

  
 9 

 
of this Agreement shall be enforced as if such invalid, illegal or unenforceable clause or provision had (to the extent not enforceable) never been contained in this Agreement. Notwithstanding
the forgoing, if the value of this Agreement based upon the substantial benefit of the bargain for any party is materially impaired, which determination as made by the presiding court or arbitrator of competent jurisdiction shall be binding, then
both parties agree to substitute such provision(s) through good faith negotiations. 
 * * * * * 

Attachment: Annex A: Form of Stock Option Exercise Notice and Agreement 

  
 10 

 ANNEX A 

FORM OF STOCK OPTION EXERCISE NOTICE AND AGREEMENT 

 STOCK OPTION EXERCISE NOTICE AND AGREEMENT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

*NOTE: You must sign this Notice on Page 3 before submitting it to Aeglea BioTherapeutics, Inc. (the
“Company”). 
 OPTIONEE INFORMATION: Please provide the following information about
yourself (“Optionee”): 
  

									
	Name:		  
				Social Security Number:		  

	Address:		  
				Employee Number:		  

			  
						

 OPTION INFORMATION: Please provide this information on the option being exercised
(the “Option”): 
  

					
	Grant No.				
			
	Date of Grant:				Type of Stock Option:
			
	Option Price per Share: $            				 ̈ Nonqualified (NQSO)
			
	Total number of shares of Common Stock of the Company subject to the Option:				 ̈ Incentive (ISO)

 EXERCISE INFORMATION: 

Number of shares of Common Stock of the Company for which the Option is now being exercised
[                ]. (These shares are referred to below as the “Purchased Shares.”) 

Total Exercise Price Being Paid for the Purchased Shares: $             

Form of payment enclosed [check all that apply]: 
  

	 ̈	Check for $        , payable to “Aeglea BioTherapeutics, Inc..” 

 

	 ̈	Certificate(s) for                  shares of Common Stock of the Company. These shares will be valued as of the date this notice is
received by the Company. [Requires Company consent.] 

 AGREEMENTS, REPRESENTATIONS
AND ACKNOWLEDGMENTS OF OPTIONEE: By signing this Stock Option Exercise Notice and Agreement, Optionee hereby agrees with, and represents to, the Company as follows: 

 

	1.	Terms Governing. I acknowledge and agree with the Company that I am acquiring the Purchased Shares by exercise of this Option subject to all other terms and conditions of the Notice of Stock Option Grant and the
Stock Option Agreement that govern the Option, including without limitation the terms of the Company’s 2015 Equity Incentive Plan, as it may be amended (the “Plan”). 

 

	2.	 Investment Intent; Securities Law Restrictions. I represent and warrant to the Company that I am acquiring and will hold the Purchased Shares
for investment for my account only, and not with a view to, or for resale in connection with, any “distribution” of the Purchased Shares within the meaning of the Securities Act of 1933, as amended (the “Securities
Act”). I understand that the Purchased Shares have not been registered under the Securities Act by reason of a specific exemption from such 

	 	
registration requirement and that the Purchased Shares must be held by me indefinitely, unless they are subsequently registered under the Securities Act or I obtain an opinion of counsel (in form
and substance satisfactory to the Company and its counsel) that registration is not required. I acknowledge that the Company is under no obligation to register the Purchased Shares under the Securities Act or under any other securities law.

  

	3.	Restrictions on Transfer: Rule 144. I will not sell, transfer or otherwise dispose of the Purchased Shares in violation of the Securities Act, the Securities Exchange Act of 1934, or the rules promulgated
thereunder (including Rule 144 under the Securities Act described below “Rule 144”)) or of any other applicable securities laws. I am aware of Rule 144, which permits limited public resales of securities acquired in a non-public
offering, subject to satisfaction of certain conditions, which include (without limitation) that: (a) certain current public information about the Company is available; (b) the resale occurs only after the holding period required by
Rule 144 has been met; (c) the sale occurs through an unsolicited “broker’s transaction”; and (d) the amount of securities being sold during any three-month period does not exceed specified limitations. I understand
that the conditions for resale set forth in Rule 144 have not been satisfied and that the Company has no plans to satisfy these conditions in the foreseeable future. 

 

	4.	Access to Information; Understanding of Risk in Investment. I acknowledge that I have received and had access to such information as I consider necessary or appropriate for deciding whether to invest in the
Purchased Shares and that I had an opportunity to ask questions and receive answers from the Company regarding the terms and conditions of the issuance of the Purchased Shares. I am aware that my investment in the Company is a speculative investment
that has limited liquidity and is subject to the risk of complete loss. I am able, without impairing my financial condition, to hold the Purchased Shares for an indefinite period and to suffer a complete loss of my investment in the Purchased
Shares. 

  

	5.	Rights of First Refusal; Market Stand-off. I acknowledge that the Purchased Shares remain subject to the Company’s Right of First Refusal and the market stand-off covenants (sometimes referred to as the
“lock-up”), all in accordance with the applicable Notice of Stock Option Grant and the Stock Option Agreement that govern the Option. 

  

	6.	Form of Ownership. I acknowledge that the Company has encouraged me to consult my own adviser to determine the form of ownership of the Purchased Shares that is appropriate for me. In the event that I choose to
transfer my Purchased Shares to a trust, I agree to sign a Stock Transfer Agreement. In the event that I choose to transfer my Purchased Shares to a trust that is not an eligible revocable trust, I also acknowledge that the transfer will be treated
as a “disposition” for tax purposes. As a result, the favorable ISO tax treatment will be unavailable and other unfavorable tax consequences may occur. 

  

	7.	Investigation of Tax Consequences. I acknowledge that the Company has encouraged me to consult my own adviser to determine the tax consequences of acquiring the Purchased Shares at this time. 

 

	8.	Other Tax Matters. I agree that the Company does not have a duty to design or administer the Plan or its other compensation programs in a manner that minimizes my tax liabilities. I will not make any claim
against the Company or its Board, officers or employees related to tax liabilities arising from my options or my other compensation. In particular, I acknowledge that my options (including the Option) are exempt from section 409A of the
Internal Revenue Code only if the exercise price per share is at least equal to the fair market value per share of the Common Stock at the time the option was granted by the Board. Since shares of the Common Stock are not traded on an established
securities market, the determination of their fair market value was made by the Board and/or by an independent valuation firm retained by the Company. I acknowledge that there is no guarantee in either case that the Internal Revenue Service will
agree with the valuation, and I will not make any claim against the Company or its Board, officers or employees in the event that the Internal Revenue Service asserts that the valuation was too low. 

  
 2 

	9.	Spouse Consent. I agree to seek the consent of my spouse to the extent required by the Company to enforce the foregoing. 

  

	10.	Tax Withholding. As a condition of exercising this Option, I agree to make adequate provision for foreign, federal, state or other tax withholding obligations, if any, which arise upon the grant, vesting or
exercise of this Option, or disposition of the Purchased Shares, whether by withholding, direct payment to the Company, or otherwise. 

 The
undersigned hereby executes and delivers this Stock Option Exercise Notice and Agreement to agrees to be bound by its terms 
  

									
	SIGNATURE:						DATE:		
				
	  
				  
		
	Optionee’s Name:						

 [Signature Page to Stock Option Exercise Notice and Agreement] 

  
 3 

 EARLY EXERCISE FORM 

OPTION GRANT NO.      

NOTICE OF STOCK OPTION GRANT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

The Optionee named below (“Optionee”) has been granted an option (this “Option”) to purchase shares of Common
Stock, $0.001 par value per share (the “Common Stock”), of Aeglea BioTherapeutics, Inc., a Delaware corporation (the “Company”), pursuant to the Company’s 2015 Equity Incentive Plan, as amended
from time to time (the “Plan”) on the terms, and subject to the conditions, described below and in the Stock Option Agreement attached hereto as Exhibit A, including its annexes (the “Stock
Option Agreement”). 
  

			
	Optionee:		
		
	 Maximum Number of Shares Subject to this Option (the “Shares”):
		
		
	Exercise Price Per Share:		$             per share
		
	Date of Grant:		
		
	Vesting Start Date:		
		
	Exercise Schedule:		This Option is immediately exercisable for all of the Shares, subject to the terms of the Stock Option Agreement
		
	Expiration Date:		The date ten (10) years after the Date of Grant set forth above, subject to earlier expiration in the event of Termination as provided in Section 3 of the Stock Option Agreement.
		
	 Tax Status of Option:
 (Check
Only One Box):
		  ̈ Incentive Stock Option (To the fullest extent permitted by the Code)

 ̈ Nonqualified Stock Option.

(If neither box is checked, this Option is a Nonqualified Stock Option).

 Vesting Schedule [EXAMPLE ONLY]: For so long as Optionee continuously provides services to the Company (or any
Subsidiary or Parent of the Company) as an employee, officer, director, contractor or consultant, the Shares subject to this Option will vest as follows: (a) prior to the first one (1) year anniversary of the Vesting Start Date, none of
the Shares will be vested; (b) [1/4th] of the Shares will be vested on the one (1) year anniversary of the Vesting Start Date; and (c) thereafter, this Option will become
vested and exercisable with respect to an additional [1/48th] of the Shares when Optionee completes each month of continuous service following the first one (1) year anniversary
of the Vesting Start Date. 
 General; Agreement: By their signatures below, Optionee and the Company agree that this Option is granted under and
governed by this Notice of Stock Option Grant (this “Grant Notice”) and by the provisions of the Plan and the Stock Option Agreement. The Plan and the Stock Option Agreement are incorporated herein by reference. Capitalized
terms used but not defined herein shall have the meanings given to them in the Plan or in the Stock Option Agreement, as applicable. By signing below, Optionee acknowledges receipt of a copy of this Grant Notice, the Plan and the Stock Option
Agreement, represents that Optionee has carefully read and is familiar with their provisions, and hereby accepts the Option subject to all of their respective terms and conditions. Optionee acknowledges that there may be adverse tax consequences
upon exercise of the Option or disposition of the Shares and that Optionee should consult a tax adviser prior to such exercise or disposition. 

Execution and Delivery: This Grant Notice may be executed and delivered electronically whether via the Company’s intranet or the Internet site of
a third party or via email or any other means of electronic delivery specified by the Company. By Optionee’s acceptance hereof (whether written, electronic or otherwise), Optionee agrees, to the fullest extent permitted by law, that in lieu of
receiving documents in paper format, Optionee accepts the electronic delivery of any documents that the Company (or any third party the Company may designate), may deliver in connection with this grant (including the Plan, this Grant Notice, the
Stock Option Agreement, the information described in Rules 701(e)(2), (3), (4) and (5) under the Securities Act (the “701 Disclosures”), account statements, or other communications or information) whether via the
Company’s intranet or the Internet site of such third party or via email or such other means of electronic delivery specified by the Company. 

AEGLEA BIOTHERAPEUTICS, INC. 
  

									
	By /Signature:		  
				Optionee Signature:		  

	Typed Name:		  
				Optionee’s Name:		
	Title:		  
						

 ATTACHMENT: Exhibit A – Stock Option Agreement 

 Exhibit A 

Stock Option Agreement 

 EXHIBIT A 

EARLY EXERCISE FORM 

STOCK OPTION AGREEMENT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

This Stock Option Agreement (this “Agreement”) is made and entered into as of the date of grant (the “Date
of Grant”) set forth on the Notice of Stock Option Grant attached as the facing page to this Agreement (the “Grant Notice”) by and between Aeglea BioTherapeutics, Inc., a Delaware corporation (the
“Company”), and the optionee named on the Grant Notice (“Optionee”). Capitalized terms not defined in this Agreement shall have the meaning ascribed to them in the Company’s 2015 Equity Incentive
Plan, as amended from time to time (the “Plan”), or in the Grant Notice, as applicable. 
 1. GRANT OF
OPTION. The Company hereby grants to Optionee an option (this “Option”) to purchase up to the total number of shares of Common Stock of the Company, $0.001 par value per share (the “Common Stock”),
set forth in the Grant Notice as the Shares (the “Shares”) at the Exercise Price Per Share set forth in the Grant Notice (the “Exercise Price”), subject to all of the terms and conditions of the Grant
Notice, this Agreement and the Plan. If designated as an Incentive Stock Option in the Grant Notice, this Option is intended to qualify as an incentive stock option (the “ISO”) within the meaning of Section 422 of the
Internal Revenue Code of 1986, as amended (the “Code”), except that if on the Date of Grant Optionee is not subject to U.S. income tax, then this Option shall be a NQSO. 

2. EXERCISE PERIOD. 

2.1. Exercise Period of Option. Subject to the conditions set forth in this Agreement, all or part of this Option may be
exercised at any time after the Date of Grant. Shares purchased by exercising this Option may be subject to the Repurchase Option as set forth in Section 7 below. This Option will become vested during its term as to portions of the Shares in
accordance with the Vesting Schedule set forth in the Grant Notice. Notwithstanding any provision in the Plan or this Agreement to the contrary, on or after Optionee’s Termination Date, this Option may not be exercised with respect to any
Shares that are Unvested Shares on Optionee’s Termination Date. 
 2.2. Vesting of Option Shares. Shares with respect to
which this Option is vested at a given time pursuant to the Vesting Schedule set forth in the Grant Notice are “Vested Shares.” Shares with respect to which this Option is not vested at a given time pursuant to the
Vesting Schedule set forth in the Grant Notice are “Unvested Shares.” 
 2.3.
Expiration. The Option shall expire on the Expiration Date set forth in the Grant Notice or earlier as provided in Section 3 below. 

3. TERMINATION. 
 3.1.
Termination for Any Reason Except Death, Disability or Cause. Except as provided in subsection 3.2 in a case in which Optionee dies within three (3) months after Optionee is Terminated other than for Cause, if Optionee is Terminated
for any reason (other than Optionee’s death or Disability or for Cause), then (a) on and after Optionee’s Termination Date, this Option shall expire immediately with respect to any Shares that are Unvested Shares and may not be
exercised with respect to any Shares that are Unvested Shares on Optionee’s Termination Date and (b) this Option to the extent (and only to the extent) that it is exercisable with respect to Vested Shares on Optionee’s Termination
Date, may be exercised by Optionee no later than three (3) months after Optionee’s Termination Date (but in no event may this Option be exercised after the Expiration Date). 

 3.2. Termination Because of Death or Disability. If Optionee is Terminated because
of Optionee’s death or Disability (or if Optionee dies within three (3) months of the date of Optionee’s Termination for any reason other than for Cause), then (a) on and after Optionee’s Termination Date, this Option shall
expire immediately with respect to any Shares that are Unvested Shares and may not be exercised with respect to any Shares that are Unvested Shares on Optionee’s Termination Date and (b) this Option, to the extent (and only to the extent)
that it is exercisable with respect to Vested Shares on Optionee’s Termination Date, may be exercised by Optionee (or Optionee’s legal representative) no later than twelve (12) months after Optionee’s Termination Date, but in no
event later than the Expiration Date. Any exercise of this Option beyond (i) three (3) months after the date Optionee ceases to be an employee when Optionee’s Termination is for any reason other than Optionee’s death or
disability, within the meaning of Section 22(e)(3) of the Code; or (ii) twelve (12) months after the date Optionee ceases to be an employee when the termination is for Optionee’s disability, within the meaning of
Section 22(e)(3) of the Code, is deemed to be an NQSO. 
 3.3. Termination for Cause. If Optionee is Terminated for
Cause, then Optionee may exercise this Option, but only with respect to any Shares that are Vested Shares on Optionee’s Termination Date, and this Option shall expire on Optionee’s Termination Date, or at such later time and on such
conditions as may be affirmatively determined by the Committee. On and after Optionee’s Termination Date, this Option shall expire immediately with respect to any Shares that are Unvested Shares and may not be exercised with respect to any
Shares that are Unvested Shares on Optionee’s Termination Date. 
 3.4. No Obligation to Employ. Nothing in the Plan or
this Agreement shall confer on Optionee any right to continue in the employ of, or other relationship with, the Company or any Parent or Subsidiary of the Company, or limit in any way the right of the Company or any Parent or Subsidiary of the
Company to terminate Optionee’s employment or other relationship at any time, with or without Cause. 
 4. MANNER OF EXERCISE.

 4.1. Stock Option Exercise Notice and Agreement. To exercise this Option, Optionee (or in the case of exercise after
Optionee’s death or incapacity, Optionee’s executor, administrator, heir or legatee, as the case may be) must deliver to the Company an executed Stock Option Exercise Notice and Agreement in the form attached hereto as
Annex A, or in such other form as may be approved by the Committee from time to time (the “Exercise Agreement”) and payment for the shares being purchased in accordance with this Agreement. The Exercise
Agreement shall set forth, among other things, (i) Optionee’s election to exercise this Option, (ii) the number of Shares being purchased, (iii) any representations, warranties and agreements regarding Optionee’s investment
intent and access to information as may be required by the Company to comply with applicable securities laws in connection with any exercise of this Option and (iv) any other agreements required by the Company to the Company. If someone other
than Optionee exercises this Option, then such person must submit documentation reasonably acceptable to the Company verifying that such person has the legal right to exercise this Option and such person shall be subject to all of the restrictions
contained herein as if such person were Optionee. 
 4.2. Limitations on Exercise. This Option may not be exercised unless
such exercise is in compliance with all applicable federal and state securities laws, as they are in effect on the date of exercise. 

4.3. Payment. The Exercise Agreement shall be accompanied by full payment of the Exercise Price for the shares being purchased
in cash (by check or wire transfer), or where permitted by law: 
 (a) by cancellation of indebtedness of the Company owed to Optionee;

  
 2 

 (b) by surrender of shares of the Company that are free and clear of all security interests,
pledges, liens, claims or encumbrances and: (i) for which the Company has received “full payment of the purchase price” within the meaning of SEC Rule 144 (and, if such shares were purchased from the Company by use of a
promissory note, such note has been fully paid with respect to such shares) or (ii) that were obtained by Optionee in the public market; 

(c) by participating in a formal cashless exercise program implemented by the Committee in connection with the Plan; 

(d) provided that a public market for the Common Stock exists, subject to compliance with applicable law, by exercising as set forth below,
through a “same day sale” commitment from Optionee and a broker-dealer whereby Optionee irrevocably elects to exercise this Option and to sell a portion of the Shares so purchased sufficient to pay the total Exercise Price, and whereby the
broker-dealer irrevocably commits upon receipt of such Shares to forward the total Exercise Price directly to the Company; or 
 (e) by any
combination of the foregoing or any other method of payment approved by the Committee that constitutes legal consideration for the issuance of Shares. 

4.4. Tax Withholding. Prior to the issuance of the Shares upon exercise of the Option, Optionee must pay or provide for any
applicable federal, state and local withholding obligations of the Company. If the Committee permits, Optionee may provide for payment of withholding taxes upon exercise of the Option by requesting that the Company retain the minimum number of
Shares with a Fair Market Value equal to the minimum amount of taxes required to be withheld; or to arrange a mandatory “sell to cover” on Participant’s behalf (without further authorization); but in no event will the Company withhold
Shares or “sell to cover” if such withholding would result in adverse accounting consequences to the Company. In case of stock withholding or a sell to cover, the Company shall issue the net number of Shares to Optionee by deducting the
Shares retained from the Shares issuable upon exercise. 
 4.5. Issuance of Shares. Provided that the Exercise Agreement and
payment are in form and substance satisfactory to counsel for the Company, the Company shall issue the Shares issuable upon a valid exercise of this Option registered in the name of Optionee, Optionee’s authorized assignee, or Optionee’s
legal representative, and shall deliver certificates representing the Shares with the appropriate legends affixed thereto. 
 5.
COMPLIANCE WITH LAWS AND REGULATIONS. The Plan and this Agreement are intended to comply with Section 25102(o) and Rule 701. Any provision of this Agreement that is inconsistent with Section 25102(o) or Rule 701
shall, without further act or amendment by the Company or the Committee, be reformed to comply with the requirements of Section 25102(o) and/or Rule 701. The exercise of this Option and the issuance and transfer of Shares shall be subject to
compliance by the Company and Optionee with all applicable requirements of federal and state securities laws and with all applicable requirements of any stock exchange on which the Common Stock may be listed at the time of such issuance or transfer.
Optionee understands that the Company is under no obligation to register or qualify the Shares with the SEC, any state securities commission or any stock exchange to effect such compliance. 

6. NONTRANSFERABILITY OF OPTION. This Option may not be transferred in any manner other than by will or by the laws of
descent and distribution, and, with respect to NQSOs, by instrument to a testamentary trust in which the options are to be passed to beneficiaries upon the death of the trustor (settlor) or a revocable trust, or by gift to “immediate
family” as that term is defined in 17 C.F.R. 240.16a-1(e), and may be exercised during the lifetime of Optionee only by Optionee or in the event of Optionee’s incapacity, by Optionee’s legal representative. The terms of this Option
shall be binding upon the executors, administrators, successors and assigns of Optionee. 

  
 3 

 7. COMPANY’S REPURCHASE OPTION FOR UNVESTED SHARES. If Optionee is Terminated for any
reason, or no reason, including without limitation, Optionee’s death, Disability, voluntary resignation or termination by the Company with or without Cause and Optionee has acquired Unvested Shares by exercising this Option, then the Company
and/or its assignee(s) shall have the option to repurchase all or a portion of Optionee’s Unvested Shares (as defined in Section 2.2 of this Agreement) as of the Termination Date on the terms and conditions set forth in this Section 7
(the “Repurchase Option”). 
 7.1. Termination and Termination Date. In case of any dispute as to
whether Optionee is Terminated, the Committee shall have discretion to determine whether Optionee has been Terminated and the effective date of such Termination (the “Termination Date”). 

7.2. Exercise of Repurchase Option. Subject to the foregoing provisions of this Section, at any time within ninety
(90) days after Optionee’s Termination Date, the Company and/or its assignee(s), may elect to repurchase any or all of Optionee’s Unvested Shares by giving Optionee written notice of exercise of the Repurchase Option. 

7.3. Calculation of Repurchase Price for Unvested Shares. The Company or its assignee shall have the option to repurchase from
Optionee (or from Optionee’s personal representative as the case may be) the Unvested Shares at Optionee’s Exercise Price, as such may be proportionately adjusted for any stock split or similar change in the capital structure of the
Company as set forth in Section 2.2 of the Plan (the “Repurchase Price”). 
 7.4. Payment of Repurchase
Price. The Repurchase Price shall be payable, at the option of the Company or its assignee, by check or by cancellation of all or a portion of any outstanding indebtedness owed by Optionee to the Company and/or such assignee, or by
any combination thereof. The Repurchase Price shall be paid without interest within the term of the Repurchase Option as described in Section 7.2. 

7.5. Right of Termination Unaffected. Nothing in this Agreement shall be construed to limit or otherwise affect in any
manner whatsoever the right or power of the Company (or any Parent or Subsidiary of the Company) to terminate Optionee’s employment or other relationship with Company (or any Parent or Subsidiary of the Company) at any time, for any reason or
no reason, with or without Cause. 
 8. RESTRICTIONS ON TRANSFER. 

8.1. Disposition of Shares. Optionee hereby agrees that Optionee shall make no disposition of any of the Shares (other than as
permitted by this Agreement) unless and until: 
 (a) Optionee shall have notified the Company of the proposed disposition and provided a
written summary of the terms and conditions of the proposed disposition; 
 (b) Optionee shall have complied with all requirements of this
Agreement applicable to the disposition of the Shares; 
 (c) Optionee shall have provided the Company with written assurances, in form and
substance satisfactory to counsel for the Company, that (i) the proposed disposition does not require registration of the Shares under the Securities Act or under any applicable state securities laws or (ii) all appropriate actions
necessary for compliance with the registration requirements of the Securities Act or of any exemption from registration available under the Securities Act (including Rule 144) or applicable state securities laws have been taken; and 

  
 4 

 (d) Optionee shall have provided the Company with written assurances, in form and substance
satisfactory to the Company, that the proposed disposition will not result in the contravention of any transfer restrictions applicable to the Shares pursuant to the provisions of the regulations promulgated under Section 25102(o), Rule 701 or
under any other applicable securities laws or adversely affect the Company’s ability to rely on the exemption(s) from registration under the Securities Act or under any other applicable securities laws for the grant of the Option, the issuance
of Shares thereunder or any other issuance of securities under the Plan. 
 8.2. Restriction on Transfer. Optionee shall not
transfer, assign, grant a lien or security interest in, pledge, hypothecate, encumber or otherwise dispose of any of the Shares which are subject to the Company’s Repurchase Option or the Right of First Refusal described below, except as
permitted by this Agreement. 
 8.3. Transferee Obligations. Each person (other than the Company) to whom the Shares are
transferred by means of one of the permitted transfers specified in this Agreement must, as a condition precedent to the validity of such transfer, acknowledge in writing to the Company that such person is bound by the provisions of this Agreement
and that the transferred Shares are subject to (i) both the Company’s Repurchase Option and the Company’s Right of First Refusal granted hereunder and (ii) the market stand-off provisions of Section 9 below, to the same
extent such Shares would be so subject if retained by Optionee. 
 9. MARKET STANDOFF AGREEMENT. Optionee agrees that, subject to any
early release provisions that apply pro rata to stockholders of the Company according to their holdings of Common Stock (determined on an as-converted into Common Stock basis), Optionee will not, for a period of up to one hundred eighty
(180) days (plus up to an additional thirty five (35) days to the extent reasonably requested by the Company or such underwriter(s) to accommodate regulatory restrictions on the publication or other distribution of research reports or
earnings releases by the Company, including NASD and NYSE rules) following the effective date of the registration statement filed with the SEC relating to the initial underwritten sale of Common Stock of the Company to the public under the
Securities Act (the “IPO”), directly or indirectly sell, offer to sell, grant any option for the sale of, or otherwise dispose of any Common Stock or securities convertible into Common Stock, except for:
(i) transfers of Shares permitted under Section 10.6 hereof so long as such transferee furnishes to the Company and the managing underwriter their written consent to be bound by this Section 9 as a condition precedent to such
transfer; and (ii) sales of any securities to be included in the registration statement for the IPO. For the avoidance of doubt, the provisions of this Section shall only apply to the IPO. The restricted period shall in any event terminate two
(2) years after the closing date of the IPO. In order to enforce the foregoing covenant, the Company shall have the right to place restrictive legends on the certificates representing the Shares subject to this Section and to impose stop
transfer instructions with respect to the Shares until the end of such period. Optionee further agrees to enter into any agreement reasonably required by the underwriters to implement the foregoing restrictions on transfer. For the avoidance of
doubt, the foregoing provisions of this Section shall not apply to any registration of securities of the Company (a) under an employee benefit plan or (b) in a merger, consolidation, business combination or similar transaction. 

10. COMPANY’S RIGHT OF FIRST REFUSAL. Unvested Shares may not be sold or otherwise transferred, or pledged by Optionee or made
subject to a security interest, pledge or other lien without the Company’s prior written consent, which may be withheld in the Company’s sole and absolute discretion. Before any Vested Shares held by Optionee or any transferee of such
Vested Shares (either sometimes referred to herein as the “Holder”) may be sold or otherwise transferred (including, without limitation, a transfer by gift or operation of law), the Company and/or its assignee(s) will have a
right of first refusal to purchase the Vested Shares to be sold or transferred (the “Offered Shares”) on the terms and conditions set forth in this Section (the “Right of First Refusal”). 

  
 5 

 10.1. Notice of Proposed Transfer. The Holder of the Offered Shares will deliver to
the Company a written notice (the “Notice”) stating: (i) the Holder’s bona fide intention to sell or otherwise transfer the Offered Shares; (ii) the name and address of each proposed purchaser or other
transferee (the “Proposed Transferee”); (iii) the number of Offered Shares to be transferred to each Proposed Transferee; (iv) the bona fide cash price or other consideration for which the Holder proposes to
transfer the Offered Shares (the “Offered Price”); and (v) that the Holder acknowledges this Notice is an offer to sell the Offered Shares to the Company and/or its assignee(s) pursuant to the Company’s Right of
First Refusal at the Offered Price as provided for in this Agreement. 
 10.2. Exercise of Right of First Refusal. At any time
within thirty (30) days after the date of the Notice, the Company and/or its assignee(s) may, by giving written notice to the Holder, elect to purchase all (or, with the consent of the Holder, less than all) the Offered Shares proposed to be
transferred to any one or more of the Proposed Transferees named in the Notice, at the purchase price, determined as specified below. 

10.3. Purchase Price. The purchase price for the Offered Shares purchased under this Section will be the Offered Price,
provided that if the Offered Price consists of no legal consideration (as, for example, in the case of a transfer by gift) then the purchase price will be the fair market value of the Offered Shares as determined in good faith by the
Committee. If the Offered Price includes consideration other than cash, then the value of the non-cash consideration, as determined in good faith by the Committee, will conclusively be deemed to be the cash equivalent value of such non-cash
consideration. 
 10.4. Payment. Payment of the purchase price for the Offered Shares will be payable, at the option of the
Company and/or its assignee(s) (as applicable), by check or by cancellation of all or a portion of any outstanding purchase money indebtedness owed by the Holder to the Company (or to such assignee, in the case of a purchase of Offered Shares by
such assignee) or by any combination thereof. The purchase price will be paid without interest within sixty (60) days after the Company’s receipt of the Notice, or, at the option of the Company and/or its assignee(s), in the manner and at
the time(s) set forth in the Notice. 
 10.5. Holder’s Right to Transfer. If all of the Offered Shares proposed in the
Notice to be transferred to a given Proposed Transferee are not purchased by the Company and/or its assignee(s) as provided in this Section, then the Holder may sell or otherwise transfer such Offered Shares to each Proposed Transferee at the
Offered Price or at a higher price, provided that (i) such sale or other transfer is consummated within ninety (90) days after the date of the Notice, (ii) any such sale or other transfer is effected in compliance with
all applicable securities laws, and (iii) each Proposed Transferee agrees in writing that the provisions of this Section will continue to apply to the Offered Shares in the hands of such Proposed Transferee. If the Offered Shares described in
the Notice are not transferred to each Proposed Transferee within such ninety (90) day period, then a new Notice must be given to the Company pursuant to which the Company will again be offered the Right of First Refusal before any Shares held
by the Holder may be sold or otherwise transferred. 
 10.6. Exempt Transfers. Notwithstanding anything to the contrary in
this Section, the following transfers of Vested Shares will be exempt from the Right of First Refusal: (i) the transfer of any or all of the Vested Shares during Optionee’s lifetime by gift or on Optionee’s death by will or intestacy
to any member(s) of Optionee’s “Immediate Family” (as defined below) or to a trust for the benefit of Optionee and/or member(s) of Optionee’s Immediate Family, provided that each transferee or other recipient agrees
in a writing satisfactory to the Company that the provisions of this Section will continue to apply to the transferred Vested Shares in the hands of such transferee or other recipient; (ii) any transfer of Vested Shares made pursuant to a
statutory merger, statutory consolidation of the Company with or into another corporation or corporations or a conversion of the Company into another form of legal entity (except that the Right of First Refusal will continue to apply thereafter to
such Vested Shares, in which case the surviving corporation of such merger or consolidation or the resulting entity of such conversion shall succeed to the rights of the Company under this Section unless the agreement of merger

  
 6 

 
or consolidation or conversion expressly otherwise provides); or (iii) any transfer of Vested Shares pursuant to the winding up and dissolution of the Company. As used herein, the term
“Immediate Family” will mean Optionee’s spouse, the lineal descendant or antecedent, father, mother, brother or sister, child, adopted child, grandchild or adopted grandchild of Optionee or Optionee’s spouse, or the
spouse of any of the above or Spousal Equivalent, as defined herein. As used herein, a person is deemed to be a “Spousal Equivalent” provided the following circumstances are true: (i) irrespective of whether or not
Optionee and the Spousal Equivalent are the same sex, they are the sole spousal equivalent of the other for the last twelve (12) months, (ii) they intend to remain so indefinitely, (iii) neither are married to anyone else,
(iv) both are at least 18 years of age and mentally competent to consent to contract, (v) they are not related by blood to a degree of closeness that which would prohibit legal marriage in the state in which they legally reside,
(vi) they are jointly responsible for each other’s common welfare and financial obligations, and (vii) they reside together in the same residence for the last twelve (12) months and intend to do so indefinitely. 

10.7. Termination of Right of First Refusal. The Right of First Refusal will terminate as to all Shares: (i) on the
effective date of the first sale of Common Stock of the Company to the general public pursuant to a registration statement filed with and declared effective by the SEC under the Securities Act (other than a registration statement relating solely to
the issuance of Common Stock pursuant to a business combination or an employee incentive or benefit plan); (ii) on any transfer or conversion of Shares made pursuant to a statutory merger or statutory consolidation of the Company with or into
another corporation or corporations if the common stock of the surviving corporation or any direct or indirect parent corporation thereof is registered under the Exchange Act; or (iii) on any transfer or conversion of Shares made pursuant to a
statutory conversion of the Company into another form of legal entity if the common equity (or comparable equity security) of entity resulting from such conversion is registered under the Exchange Act. 

10.8. Encumbrances on Vested Shares. Optionee may grant a lien or security interest in, or pledge, hypothecate or encumber
Vested Shares only if each party to whom such lien or security interest is granted, or to whom such pledge, hypothecation or other encumbrance is made, agrees in a writing satisfactory to the Company that: (i) such lien, security interest,
pledge, hypothecation or encumbrance will not adversely affect or impair the Right of First Refusal or the rights of the Company and/or its assignee(s) with respect thereto and will not apply to such Vested Shares after they are acquired by the
Company and/or its assignees under this Section; and (ii) the provisions of this Agreement will continue to apply to such Vested Shares in the hands of such party and any transferee of such party. Optionee may not grant a lien or security
interest in, or pledge, hypothecate or encumber, any Unvested Shares. 
 11. RIGHTS AS A STOCKHOLDER. Optionee shall not have any of
the rights of a stockholder with respect to any Shares unless and until such Shares are issued to Optionee. Subject to the terms and conditions of this Agreement, Optionee will have all of the rights of a stockholder of the Company with respect to
the Shares from and after the date that Shares are issued to Optionee pursuant to, and in accordance with, the terms of the Exercise Agreement until such time as Optionee disposes of the Shares or the Company and/or its assignee(s) exercise(s) the
Repurchase Option or the Right of First Refusal. Upon an exercise of the Repurchase Option or the Right of First Refusal, Optionee will have no further rights as a holder of the Shares so purchased upon such exercise, other than the right to receive
payment for the Shares so purchased in accordance with the provisions of this Agreement, and Optionee will promptly surrender the stock certificate(s) evidencing the Shares so purchased to the Company for transfer or cancellation. 

12. ESCROW. As security for Optionee’s faithful performance of this Agreement, Optionee agrees, immediately upon receipt of the
stock certificate(s) evidencing the Shares, to deliver such certificate(s) to the Secretary of the Company or other designee of the Company (the “Escrow Holder”), who is hereby appointed to hold such certificate(s) and to
take all such actions and to effectuate all such transfers and/or releases of such Shares as are in accordance with the terms of this Agreement. Optionee 

  
 7 

 
and the Company agree that Escrow Holder will not be liable to any party to this Agreement (or to any other party) for any actions or omissions unless Escrow Holder is grossly negligent or
intentionally fraudulent in carrying out the duties of Escrow Holder under this Agreement. Escrow Holder may rely upon any letter, notice or other document executed with any signature purported to be genuine and may rely on the advice of counsel and
obey any order of any court with respect to the transactions contemplated by this Agreement and will not be liable for any act or omission taken by Escrow Holder in good faith reliance on such documents, the advice of counsel or a court order. The
Shares will be released from escrow upon termination of both the Repurchase Option and the Right of First Refusal. 
 13. RESTRICTIVE
LEGENDS AND STOP-TRANSFER ORDERS. 
 13.1. Legends. Optionee understands and agrees that the Company will place the legends
set forth below or similar legends on any stock certificate(s) evidencing the Shares, together with any other legends that may be required by state or U.S. Federal securities laws, the Company’s Certificate of Incorporation or Bylaws, any other
agreement between Optionee and the Company, or any agreement between Optionee and any third party (and any other legend(s) that the Company may become obligated to place on the stock certificate(s) evidencing the Shares under the terms of any
agreement to which the Company is or may become bound or obligated): 
 (a) THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR UNDER THE SECURITIES LAWS OF CERTAIN STATES. THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS
PERMITTED UNDER THE SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM. INVESTORS SHOULD BE AWARE THAT THEY MAY BE REQUIRED TO BEAR THE FINANCIAL RISKS OF THIS INVESTMENT FOR AN INDEFINITE PERIOD OF
TIME. THE ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES
LAWS. 
 (b) THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RESTRICTIONS ON RESALE AND TRANSFER, INCLUDING THE
REPURCHASE OPTION AND RIGHT OF FIRST REFUSAL HELD BY THE ISSUER AND/OR ITS ASSIGNEE(S) AS SET FORTH IN A STOCK OPTION AGREEMENT BETWEEN THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF
THE ISSUER. SUCH SALE AND TRANSFER RESTRICTIONS, INCLUDING THE REPURCHASE OPTION AND RIGHT OF FIRST REFUSAL, ARE BINDING ON TRANSFEREES OF THESE SHARES. 

(c) THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO A MARKET STANDOFF RESTRICTION AS SET FORTH IN A CERTAIN STOCK OPTION AGREEMENT
BETWEEN THE ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE ISSUER. AS A RESULT OF SUCH AGREEMENT, THESE SHARES MAY NOT BE TRADED PRIOR TO 180 DAYS AFTER THE EFFECTIVE DATE OF CERTAIN
PUBLIC OFFERINGS OF THE COMMON STOCK OF THE ISSUER HEREOF. SUCH RESTRICTION IS BINDING ON TRANSFEREES OF THESE SHARES. 
 13.2.
Stop-Transfer Instructions. Optionee agrees that, to ensure compliance with the restrictions imposed by this Agreement, the Company may issue appropriate “stop-transfer” instructions to its transfer agent, if any, and if the
Company transfers its own securities, it may make appropriate notations to the same effect in its own records. 

  
 8 

 13.3. Refusal to Transfer. The Company will not be required (i) to transfer on
its books any Shares that have been sold or otherwise transferred in violation of any of the provisions of this Agreement or (ii) to treat as owner of such Shares, or to accord the right to vote or pay dividends to any purchaser or other
transferee to whom such Shares have been so transferred. 
 14. CERTAIN TAX CONSEQUENCES. Set forth below is a brief summary as of
the Effective Date of the Plan of some of the federal tax consequences of exercise of the Option and disposition of the Shares. THIS SUMMARY IS NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE. OPTIONEE SHOULD CONSULT A
TAX ADVISER BEFORE EXERCISING THE OPTION OR DISPOSING OF THE SHARES. 
 14.1. Exercise of ISO. If the Option qualifies
as an ISO, there will be no regular federal income tax liability upon the exercise of the Option, although the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the Exercise Price will be treated as a tax preference
item for federal alternative minimum tax purposes and may subject Optionee to the alternative minimum tax in the year of exercise. 

14.2. Exercise of Nonqualified Stock Option. If the Option does not qualify as an ISO, there may be a regular federal income tax
liability upon the exercise of the Option. Optionee will be treated as having received compensation income (taxable at ordinary income tax rates) equal to the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the
Exercise Price. If Optionee is a current or former employee of the Company, the Company may be required to withhold from Optionee’s compensation or collect from Optionee and pay to the applicable taxing authorities an amount equal to a
percentage of this compensation income at the time of exercise. 
 14.3. Disposition of Shares. The following tax consequences
may apply upon disposition of the Shares. 
 (a) Incentive Stock Options. If the Shares are held for more than twelve
(12) months after the date of purchase of the Shares pursuant to the exercise of an ISO and are disposed of more than two (2) years after the Date of Grant, any gain realized on disposition of the Shares will be treated as long term
capital gain for federal income tax purposes. If Vested Shares purchased under an ISO are disposed of within the applicable one (1) year or two (2) year period, any gain realized on such disposition will be treated as compensation income
(taxable at ordinary income rates in the year of the disposition) to the extent of the excess, if any, of the Fair Market Value of the Shares on the date of exercise over the Exercise Price. To the extent the Shares were exercised prior to vesting
coincident with the filing of an 83(b) Election, the amount taxed because of a disqualifying disposition will be based upon the excess, if any, of the fair market value on the date of vesting over the exercise price. 

(b) Nonqualified Stock Options. If the Shares are held for more than twelve (12) months after the date of purchase of the Shares
pursuant to the exercise of an NQSO, any gain realized on disposition of the Shares will be treated as long term capital gain. 
 14.4.
Section 83(b) Election for Unvested Shares. With respect to Unvested Shares, which are subject to the Repurchase Option, unless an election is filed by Optionee with the Internal Revenue Service (and, if necessary, the proper state
taxing authorities), within thirty (30) days of the purchase of the Unvested Shares, electing pursuant to Section 83(b) of the Code (and similar state tax provisions, if applicable) to be taxed currently on any difference between
the Exercise Price of the Unvested Shares and their Fair Market Value on the date of purchase, there may be a recognition of taxable income (including, where applicable, alternative minimum taxable income) to Optionee, measured by the excess, if
any, of the Fair Market Value of the Unvested Shares at the time they cease to be Unvested Shares, over the Exercise Price of the Unvested Shares. 

  
 9 

 15. GENERAL PROVISIONS. 

15.1. Interpretation. Any dispute regarding the interpretation of this Agreement shall be submitted by Optionee or the Company to
the Committee for review. The resolution of such a dispute by the Committee shall be final and binding on the Company and Optionee. 

15.2. Entire Agreement. The Plan, the Grant Notice and the Exercise Agreement are each incorporated herein by reference. This
Agreement, the Grant Notice, the Plan and the Exercise Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede all prior undertakings and agreements with respect to such subject matter. 

16. NOTICES. Any and all notices required or permitted to be given to a party pursuant to the provisions of this Agreement will be in
writing and will be effective and deemed to provide such party sufficient notice under this Agreement on the earliest of the following: (i) at the time of personal delivery, if delivery is in person; (ii) at the time an electronic
confirmation of receipt is received, if delivery is by email; (iii) at the time of transmission by facsimile, addressed to the other party at its facsimile number specified herein (or hereafter modified by subsequent notice to the parties
hereto), with confirmation of receipt made by both telephone and printed confirmation sheet verifying successful transmission of the facsimile; (iv) one (1) business day after deposit with an express overnight courier for United States
deliveries, or two (2) business days after such deposit for deliveries outside of the United States, with proof of delivery from the courier requested; or (v) three (3) business days after deposit in the United States mail by
certified mail (return receipt requested) for United States deliveries. Any notice for delivery outside the United States will be sent by email, facsimile or by express courier. Any notice not delivered personally or by email will be sent with
postage and/or other charges prepaid and properly addressed to Optionee at the last known address or facsimile number on the books of the Company, or at such other address or facsimile number as such other party may designate by one of the indicated
means of notice herein to the other parties hereto or, in the case of the Company, to it at its principal place of business. Notices to the Company will be marked “Attention: Chief Financial Officer.” Notices by facsimile shall be machine
verified as received. 
 17. SUCCESSORS AND ASSIGNS. The Company may assign any of its rights under this Agreement including its
rights to purchase Shares under both the Right of First Refusal and Repurchase Option. This Agreement shall be binding upon and inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer set forth
herein, this Agreement shall be binding upon Optionee and Optionee’s heirs, executors, administrators, legal representatives, successors and assigns. 

18. GOVERNING LAW. This Agreement shall be governed by and construed in accordance with the internal laws of the State of California as
such laws are applied to agreements between California residents entered into and to be performed entirely within California. If any provision of this Agreement is determined by a court of law to be illegal or unenforceable, then such provision will
be enforced to the maximum extent possible and the other provisions will remain fully effective and enforceable. 
 19. FURTHER
ASSURANCES. The parties agree to execute such further documents and instruments and to take such further actions as may be reasonably necessary to carry out the purposes and intent of this Agreement. 

20. TITLES AND HEADINGS. The titles, captions and headings of this Agreement are included for ease of reference only and will be
disregarded in interpreting or construing this Agreement. Unless otherwise specifically stated, all references herein to “sections” and “exhibits” will mean “sections” and “exhibits” to this Agreement. 

21. COUNTERPARTS. This Agreement may be executed in any number of counterparts, each of which when so executed and delivered
will be deemed an original, and all of which together shall constitute one and the same agreement. 

  
 10 

 22. SEVERABILITY. If any provision of this Agreement is determined by any court or
arbitrator of competent jurisdiction to be invalid, illegal or unenforceable in any respect, such provision will be enforced to the maximum extent possible given the intent of the parties hereto. If such clause or provision cannot be so enforced,
such provision shall be stricken from this Agreement and the remainder of this Agreement shall be enforced as if such invalid, illegal or unenforceable clause or provision had (to the extent not enforceable) never been contained in this Agreement.
Notwithstanding the forgoing, if the value of this Agreement based upon the substantial benefit of the bargain for any party is materially impaired, which determination as made by the presiding court or arbitrator of competent jurisdiction shall be
binding, then both parties agree to substitute such provision(s) through good faith negotiations. 
 * * * * * 

Attachments: 
 Annex A: Form of Stock Option
Exercise Notice and Agreement 

  
 11 

 ANNEX A 

FORM OF STOCK OPTION EXERCISE NOTICE AND AGREEMENT 

 EARLY EXERCISE FORM 

STOCK OPTION EXERCISE NOTICE AND AGREEMENT 

AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

*NOTE: You must sign this Notice on Page 3 before
submitting it to Aeglea BioTherapeutics, Inc. (the “Company”). 
 OPTIONEE
INFORMATION: Please provide the following information about yourself (“Optionee”): 
  

									
	Name:		  
				Social Security Number:		  

	Address:		  
				Employee Number:		  

			  
						

 OPTION INFORMATION: Please provide this information on the option being
exercised (the “Option”): 
  

			
	Grant No.		
		
	Date of Grant:		Type of Stock Option:
		
	Option Price per Share: $            		 ̈ Nonqualified (NQSO)
		
	Total number of shares of Common Stock of the Company subject to the Option:		 ̈ Incentive (ISO)

 EXERCISE INFORMATION: 

Number of shares of Common Stock of the Company for which the Option is now being exercised
[                ]. (These shares are referred to below as the “Purchased Shares.”) 

Total Exercise Price Being Paid for the Purchased Shares: $         

Form of payment enclosed [check all that apply]: 
  

	 ̈	Check for $        , payable to “Aeglea BioTherapeutics, Inc..” 

 

	 ̈	Certificate(s) for                  shares of Common Stock of the Company. These shares will be valued as of the date this notice is
received by the Company. [Requires Company consent.] 

 AGREEMENTS, REPRESENTATIONS
AND ACKNOWLEDGMENTS OF OPTIONEE: By signing this Stock Option Exercise Notice and Agreement, Optionee hereby agrees with, and represents to, the Company as
follows: 
  

	1.	Terms Governing. I acknowledge and agree with the Company that I am acquiring the Purchased Shares by exercise of this Option subject to all other terms and conditions of the Notice of Stock Option Grant and the
Stock Option Agreement that govern the Option, including without limitation the terms of the Company’s 2015 Equity Incentive Plan, as it may be amended (the “Plan”). 

 

	2.	 Investment Intent; Securities Law Restrictions. I represent and warrant to the Company that I am acquiring and will hold the Purchased Shares
for investment for my account only, and not with a view to, or for resale in connection with, any “distribution” of the Purchased Shares within the meaning of the Securities Act of 1933, as amended (the “Securities
Act”). I understand that the Purchased Shares 

 EARLY EXERCISE FORM 

 

	 	
have not been registered under the Securities Act by reason of a specific exemption from such registration requirement and that the Purchased Shares must be held by me indefinitely, unless they
are subsequently registered under the Securities Act or I obtain an opinion of counsel (in form and substance satisfactory to the Company and its counsel) that registration is not required. I acknowledge that the Company is under no obligation to
register the Purchased Shares under the Securities Act or under any other securities law. 

  

	3.	Restrictions on Transfer: Rule 144. I will not sell, transfer or otherwise dispose of the Purchased Shares in violation of the Securities Act, the Securities Exchange Act of 1934, or the rules promulgated
thereunder (including Rule 144 under the Securities Act described below “Rule 144”)) or of any other applicable securities laws. I am aware of Rule 144, which permits limited public resales of securities acquired in a non-public
offering, subject to satisfaction of certain conditions, which include (without limitation) that: (a) certain current public information about the Company is available; (b) the resale occurs only after the holding period required by
Rule 144 has been met; (c) the sale occurs through an unsolicited “broker’s transaction;” and (d) the amount of securities being sold during any three-month period does not exceed specified limitations. I understand
that the conditions for resale set forth in Rule 144 have not been satisfied and that the Company has no plans to satisfy these conditions in the foreseeable future. 

 

	4.	Access to Information; Understanding of Risk in Investment. I acknowledge that I have received and had access to such information as I consider necessary or appropriate for deciding whether to invest in the
Purchased Shares and that I had an opportunity to ask questions and receive answers from the Company regarding the terms and conditions of the issuance of the Purchased Shares. I am aware that my investment in the Company is a speculative investment
that has limited liquidity and is subject to the risk of complete loss. I am able, without impairing my financial condition, to hold the Purchased Shares for an indefinite period and to suffer a complete loss of my investment in the Purchased
Shares. 

  

	5.	Rights of First Refusal; Repurchase Options; Market Stand-off. I acknowledge that the Purchased Shares remain subject to the Company’s Right of First Refusal, the Company’s Repurchase Option (with
respect to unvested Purchased Shares) and the market stand-off covenants (sometimes referred to as the “lock-up”), all in accordance with the applicable Notice of Stock Option Grant and the Stock Option Agreement that govern the Option

  

	6.	Form of Ownership. I acknowledge that the Company has encouraged me to consult my own adviser to determine the form of ownership of the Purchased Shares that is appropriate for me. In the event that I choose to
transfer my Purchased Shares to a trust, I agree to sign a Stock Transfer Agreement. In the event that I choose to transfer my Purchased Shares to a trust that is not an eligible revocable trust, I also acknowledge that the transfer will be treated
as a “disposition” for tax purposes. As a result, the favorable ISO tax treatment will be unavailable and other unfavorable tax consequences may occur. 

  

	7.	Investigation of Tax Consequences. I acknowledge that the Company has encouraged me to consult my own adviser to determine the tax consequences of acquiring the Purchased Shares at this time. 

 

	8.	 Other Tax Matters. I agree that the Company does not have a duty to design or administer the Plan or its other compensation programs in a
manner that minimizes my tax liabilities. I will not make any claim against the Company or its Board, officers or employees related to tax liabilities arising from my options or my other compensation. In particular, I acknowledge that my options
(including the Option) are exempt from Section 409A of the Internal Revenue Code only if the exercise price per share is at least equal to the fair market value per share of the Common Stock at the time the option was granted by the Board.
Since shares of the Common Stock are not traded on an established securities market, the determination of their fair market value was made by the Board and/or by an independent valuation firm retained by the Company. I acknowledge that there is no
guarantee in 

  
 2 

 EARLY EXERCISE FORM 

 

	 	
either case that the Internal Revenue Service will agree with the valuation, and I will not make any claim against the Company or its Board of Directors, officers or employees in the event that
the Internal Revenue Service asserts that the valuation was too low. 

  

	9.	Spouse Consent. I agree to seek the consent of my spouse to the extent required by the Company to enforce the foregoing. 

  

	10.	Tax Withholding. As a condition of exercising this Option, I agree to make adequate provision for foreign, federal, state or other tax withholding obligations, if any, which arise upon the grant, vesting or
exercise of this Option, or disposition of the Purchased Shares, whether by withholding, direct payment to the Company, or otherwise. 

IMPORTANT NOTE: UNVESTED PURCHASED SHARES ARE SUBJECT TO REPURCHASE BY THE COMPANY. PLEASE CONSULT WITH YOUR TAX ADVISER CONCERNING THE
ADVISABILITY OF FILING AN 83(b) ELECTION WITH THE INTERNAL REVENUE SERVICE WHICH MUST BE FILED WITHIN THIRTY (30) DAYS AFTER THE PURCHASE OF SHARES TO BE EFFECTIVE. 

A form of Election under Section 83(b) is attached hereto as Exhibit 1 for reference. Unless an 83(b) election is timely filed with the
Internal Revenue Service (and, if necessary, the proper state taxing authorities), electing pursuant to Section 83(b) of the Internal Revenue Code (and similar state tax provisions, if applicable) to be taxed currently on any difference between
the purchase price of the Unvested Purchased Shares and their fair market value on the date of purchase, there may be a recognition of taxable income (including, where applicable, alternative minimum taxable income) to you, measured by the excess,
if any, of the Fair Market Value of the Unvested Purchased Shares at the time they cease to be Unvested Purchased Shares, over the purchase price of the Unvested Purchased Shares. 

The undersigned hereby executes and delivers this Stock Option Exercise Notice and Agreement and agrees to be bound by its terms 

 

							
	SIGNATURE:	 	 	 	DATE:	 	 
				
	  
	 		 	  
	 	
	Optionee’s Name:	 		 		 	

 Attachments: 
 Exhibit
1 – Section 83(b) Election Form 
 [Signature Page to Stock Option Exercise Notice and Agreement] 

  
 3 

 EARLY EXERCISE FORM 

EXHIBIT 1 
 SECTION
83(b) ELECTION 

 ELECTION UNDER SECTION 83(b) OF THE 

INTERNAL REVENUE CODE 
 The undersigned
Taxpayer hereby elects, pursuant to Section 83(b) of the Internal Revenue Code of 1986, as amended, to include the excess, if any, of the fair market value of the property described below at the time of transfer over the amount paid for such
property, as compensation for services in the calculation of: (1) regular gross income; (2) alternative minimum taxable income; or (3) disqualifying disposition gross income, as the case may be. 

 

							
	 1.      
		TAXPAYER’S NAME:		  
		
				
			TAXPAYER’S ADDRESS:		  
		
					  
		
				
			SOCIAL SECURITY NUMBER:		  
		
		
	 2.      
		The property with respect to which the election is made is described as follows:              shares of Common Stock, par value $0.001 per share, of Aeglea
BioTherapeutics, Inc., a Delaware corporation (the “Company”), which were transferred upon exercise of an option by the Company, which is Taxpayer’s employer or the corporation for whom the Taxpayer performs
services.
		
	 3.      
		The date on which the shares were transferred was pursuant to the exercise of the option was             ,         and
this election is made for calendar year         .
		
	 4.      
		The shares are subject to the following restrictions: The Company may repurchase all or a portion of the shares at the Taxpayer’s original purchase price under certain conditions at the time of Taxpayer’s
termination of employment or services.
		
	 5.      
		The fair market value of the shares (without regard to restrictions other than restrictions which by their terms will never lapse) was $         per share x
                 shares = $         at the time of exercise of the option.
		
	 6.      
		The amount paid for such shares upon exercise of the option was $         per share x
                 shares = $        .
		
	 7.      
		The Taxpayer has submitted a copy of this statement to the Company.
		
	 8.      
		The amount to include in gross income is $        . [The result of the amount reported in Item 5 minus the amount reported in Item 6.]

 THIS ELECTION MUST BE FILED WITH THE INTERNAL REVENUE SERVICE (“IRS”), AT THE OFFICE WHERE
THE TAXPAYER FILES ANNUAL INCOME TAX RETURNS, WITHIN 30 DAYS AFTER THE DATE OF TRANSFER OF THE SHARES, AND MUST ALSO BE FILED WITH THE TAXPAYER’S INCOME TAX RETURNS FOR THE CALENDAR YEAR. THE ELECTION CANNOT BE REVOKED WITHOUT THE
CONSENT OF THE IRS. 
  

							
	Dated:				
                     
                    
		
					Taxpayer’s Signature		

 AEGLEA BIOTHERAPEUTICS, INC. 

2015 EQUITY INCENTIVE PLAN 

RESTRICTED STOCK PURCHASE AGREEMENT 

This Restricted Stock Purchase Agreement (the “Agreement”) is made and entered into as of
                     (the “Effective Date”) by and between Aeglea BioTherapeutics, Inc., a Delaware corporation (the
“Company”), and                  (“Purchaser”). Capitalized terms not defined herein shall have the meanings
ascribed to them in the Company’s 2015 Equity Incentive Plan, as may be amended from time to time (the “Plan”). 

1. PURCHASE OF SHARES. 

1.1 Agreement to Purchase and Sell Shares. On the Effective Date and subject to the terms and conditions of this
Agreement and the Plan, Purchaser hereby purchases from the Company, and the Company hereby sells to Purchaser,                 
(        ) shares of the Company’s Common Stock (the “Shares”), at the price of
                 ($        ) per share (the “Purchase Price Per Share”) for a Total
Purchase Price of                  ($        ) (the “Purchase Price”). As used in this
Agreement, the term “Shares” includes the Shares purchased under this Agreement and all securities received (a) in replacement of the Shares, (b) as a result of stock dividends or stock splits with respect to the
Shares, and (c) in replacement of the Shares in a merger, recapitalization, reorganization or similar corporate transaction. 
 1.2
Payment. Purchaser hereby delivers payment of the Purchase Price as follows (check and complete as appropriate): 
  

	 ̈	in cash (by check) in the amount of $        , receipt of which is acknowledged by the Company. 

 

	 ̈	by cancellation of indebtedness of the Company owed to Purchaser in the amount of $        . 

 

	 ̈	by the waiver hereby of compensation due or accrued for services rendered in the amount of $        . 

 

	 ̈	by delivery of                  fully-paid, nonassessable and vested shares of the Common Stock of the Company owned by Purchaser free and
clear of all liens, claims, encumbrances or security interests, valued at the current Fair Market Value of $         per share (a) for which the Company has received “full payment of the purchase
price” within the meaning of SEC Rule 144, (if purchased by use of a promissory note, such note has been fully paid with respect to such vested shares), or (b) that were obtained by Purchaser in the open public market. 

2. DELIVERIES. 
 2.1
Deliveries by the Purchaser. Purchaser hereby delivers to the Company at its principal executive offices: (a) this completed and signed Agreement, and (b) the Purchase Price, paid by delivery of the form of payment specified in
Section 1.2. 
 2.2 Deliveries by the Company. Upon its receipt of the Purchase Price, payment or other provision for any
applicable tax obligations, if any, and all the documents to be executed and delivered by Purchaser to the Company as provided herein, the Company will issue a duly executed stock certificate evidencing the Shares in the name of Purchaser with the
appropriate legends affixed thereto, to 

  
 1 

 
be placed in escrow as provided in Section 7.2 to secure performance of Purchaser’s obligations under Sections 5 and 6 until expiration or termination of the Company’s Repurchase
Option and Refusal Right (as such terms are defined in Sections 5 and 6, respectively). 
 3. REPRESENTATIONS AND WARRANTIES OF
PURCHASER. Purchaser represents and warrants to the Company as follows. 
 3.1 Agrees to Terms of the Plan. Purchaser has
received a copy of the Plan, has read and understands the terms of the Plan and this Agreement, and agrees to be bound by their terms and conditions. 

3.2 Acknowledgment of Tax Risks. Purchaser acknowledges that there may be adverse tax consequences upon the purchase and the
disposition of the Shares, and that Purchaser has been advised by the Company to consult a tax adviser prior to such purchase or disposition. Purchaser further acknowledges that Purchaser is not relying on the Company or its counsel for tax advice
regarding Purchaser’s purchaser or disposition of the Shares or the tax consequences to Purchaser of this Agreement. 
 3.3
Shares Not Registered or Qualified. Purchaser understands and acknowledges that the Shares have not been registered with the SEC under the Securities Act, or with any securities regulatory agency administering any state securities laws,
and that, notwithstanding any other provision of this Agreement to the contrary, the purchase of any Shares is expressly conditioned upon compliance with the Securities Act and all applicable state securities laws. Purchaser agrees to cooperate with
the Company to ensure compliance with such laws. 
 3.4 No Transfer Unless Registered or Exempt; Contractual Restrictions on
Transfers. Purchaser understands that Purchaser may not transfer any Shares unless such Shares are registered under the Securities Act or qualified under applicable state securities laws or unless, in the opinion of counsel to the Company,
exemptions from such registration and qualification requirements are available. Purchaser understands that only the Company may file a registration statement with the SEC and that the Company is under no obligation to do so with respect to the
Shares. Purchaser has also been advised that exemptions from registration and qualification may not be available or may not permit Purchaser to transfer all or any of the Shares in the amounts or at the times proposed by Purchaser. Purchaser further
acknowledges that this Agreement imposes additional restrictions on transfer of the Shares. 
 3.5 SEC Rule 701. Shares that
are issued pursuant to SEC Rule 701 promulgated under the Securities Act may become freely tradable by non-affiliates (under limited conditions regarding the method of sale) ninety (90) days after the first sale of Common Stock of the
Company to the general public pursuant to a registration statement filed with and declared effective by the SEC, subject to the lengthier market standoff agreement contained in Section 4 of this Agreement or any other agreement entered into by
Purchaser. Affiliates must comply with the provisions (other than the holding period requirements) of Rule 144 which permits certain limited sales of unregistered securities. Rule 144 is not presently available with respect to the Shares and,
in any event, requires that the Shares be held for a minimum of six (6) months, and in certain cases one (1) year, after they have been purchased and paid for (within the meaning of Rule 144). Purchaser understands that use of a
promissory note as payment for the Shares may not be deemed to be “full payment of the purchase price” within the meaning of Rule 144 unless certain conditions are met and that, accordingly, the Rule 144 holding period of such Shares may
not begin to run until such Shares are fully paid for within the meaning of Rule 144. Purchaser understands that Rule 144 may indefinitely restrict transfer of the Shares so long as Purchaser remains an “affiliate” of the Company or if
“current public information” about the Company (as defined in Rule 144) is not publicly available. 

  
 2 

 3.6 Access to Information. Purchaser has had access to all information regarding
the Company and its present and prospective business, assets, liabilities and financial condition that Purchaser reasonably considers important in making the decision to purchase the Shares, and Purchaser has had ample opportunity to ask questions
of the Company’s representatives concerning such matters and this investment. 
 3.7 Understanding of Risks. Purchaser is
fully aware of: (a) the highly speculative nature of the investment in the Shares; (b) the financial hazards involved; (c) the lack of liquidity of the Shares and the restrictions on transferability of the Shares (e.g., that
Purchaser may not be able to sell or dispose of the Shares or use them as collateral for loans); (d) the qualifications and backgrounds of the management of the Company; and (e) the tax consequences of investment in, and disposition of,
the Shares. 
 3.8 Purchase for Own Account for Investment. Purchaser is purchasing the Shares for Purchaser’s own
account for investment purposes only and not with a view to, or for sale in connection with, a distribution of the Shares within the meaning of the Securities Act. Purchaser has no present intention of selling or otherwise disposing of all or any
portion of the Shares and no one other than Purchaser has any beneficial ownership of any of the Shares. 
 3.9 No General
Solicitation. At no time was Purchaser presented with or solicited by any publicly issued or circulated newspaper, mail, radio, television or other form of general advertising or solicitation in connection with the offer, sale and purchase
of the Shares. 
 3.10 SEC Rule 144. Purchaser has been advised that SEC Rule 144 promulgated under the Securities Act, which
permits certain limited sales of unregistered securities, is not presently available with respect to the Shares and, in any event, requires that the Shares be held for a minimum of six (6) months, and in certain cases one (1) year, after
they have been purchased and paid for (within the meaning of Rule 144), subject to the lengthier market standoff agreement contained in Section 4 of this Agreement or any other agreement entered into by Purchaser. Purchaser understands
that Rule 144 may indefinitely restrict transfer of the Shares so long as Purchaser remains an “affiliate” of the Company or if “current public information” about the Company (as defined in Rule 144) is not publicly available.

 4. MARKET STANDOFF AGREEMENT. Subject to the provisions of this Section, Purchaser agrees in connection with any registration of
the Company’s securities under the Securities Act or other registered public offering that, Purchaser will not sell or otherwise dispose of any Shares without the prior written consent of the Company or such managing underwriters, as the case
may be, for a period of time (not to exceed one hundred eighty (180) days) after the effective date of such registration requested by such managing underwriters and subject to all restrictions as the Company or the managing underwriters may
specify for employee-stockholders generally; provided however, that if during the last seventeen (17) days of the restricted period the Company issues an earnings release or material news, or a material event relating to the
Company occurs, or prior to the expiration of the restricted period the Company announces that it will release earnings results during the sixteen (16)-day period beginning on the last day of the restricted period, then, if required by the
underwriters or the Company, for so long as, and to the extent that, Rule 2711 or any successor rule of the Financial Industry Regulatory Authority applies, the restrictions imposed by this Section 4 shall continue to apply until the expiration
of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event. The restricted period shall in any event terminate two (2) years after the closing date of the Company’s
initial public offering. For purposes of this Section 4, the term “Company” shall include any wholly-owned subsidiary of the Company into which the Company merges or consolidates. In order to enforce the foregoing covenant, the
Company shall have the right to place restrictive legends on the certificates representing the shares subject to this Section and to impose stop transfer instructions with respect to the Shares until the end of such period. Purchaser further agrees
that the underwriters of any 

  
 3 

 
such registered public offering shall be third party beneficiaries of this Section 4 and agrees to enter into any agreement reasonably required by the underwriters to implement the
foregoing. Notwithstanding anything in this Section to the contrary, for the avoidance of doubt, the foregoing provisions of this Section shall not apply to any registration of securities of the Company (a) under an employee benefit plan or
(b) in a merger, consolidation, business combination or similar transaction. 
 5. COMPANY’S REPURCHASE OPTION FOR UNVESTED
SHARES. The Company, or (subject to Section 5.6) its assignee, shall have the option to repurchase all or a portion of the Purchaser’s Shares that are Unvested Shares (as defined below) on the Termination Date on the terms and
conditions set forth in this Section (the “Repurchase Option”) if Purchaser is Terminated (as defined in the Plan) for any reason, or no reason, including without limitation, Purchaser’s death, Disability (as defined in
the Plan), voluntary resignation or termination by the Company with or without Cause. 
 5.1 Termination and Termination Date.
In case of any dispute as to whether Purchaser is Terminated, the Committee shall have discretion to determine in good faith whether Purchaser has been Terminated and the effective date of such Termination (the “Termination
Date”). 
 5.2 Vested and Unvested Shares. Shares that are vested pursuant to the schedule set forth in this
Section 5.2 are “Vested Shares.” Shares that are not vested pursuant to such schedule are “Unvested Shares.” On the Effective Date,
                    of the Shares will be Unvested Shares (the “Initial Unvested Shares”). Provided Purchaser continues to
provide services to the Company or any Subsidiary or Parent of the Company at all times from the Effective Date until                     (the
“First Vesting Date”), then on the First Vesting Date one-fourth (1/4th) of the Initial Unvested Shares will become Vested Shares, and on the same day of each
succeeding calendar month thereafter (or if there is no such day in any month, then the last day of such calendar month), an additional one forty-eighth 1/48th of the Initial Unvested Shares shall
vest until the earliest to occur of (a) the date all of the Shares are Vested Shares, (b) the Termination Date or (c) the date vesting otherwise terminates pursuant to this Agreement or the Plan. No fractional Shares shall be issued.
No Shares will become Vested Shares after the Termination Date. The number of the Shares that are Vested Shares or Unvested Shares will be proportionally adjusted to reflect any stock split, reverse stock split or similar change in the capital
structure of the Company as set forth in Section 2.2 of the Plan occurring after the Effective Date. 
 5.3 Exercise of
Repurchase Option. At any time within ninety (90) days after the Purchaser’s Termination Date, the Company, or its assignee, may, at its option, elect to repurchase any or all the Purchaser’s Shares that are Unvested Shares on
the Termination Date by giving Purchaser written notice of exercise of the Repurchase Option, specifying the number of Unvested Shares to be repurchased. Such Unvested Shares shall be repurchased at the Purchase Price Per Share, proportionately
adjusted for any stock split, reverse stock split or similar change in the capital structure of the Company as set forth in Section 2.2 of the Plan occurring after the Effective Date (the “Repurchase Price”). The
Repurchase Price shall be payable, at the option of the Company or its assignee, by check or by cancellation of all or a portion of any outstanding indebtedness owed by Purchaser to the Company and/or such assignee, or by any combination thereof.
The Repurchase Price shall be paid without interest within the term of the Repurchase Option as described in the first sentence of this Section 5.3. The Company may, at its option, decline to exercise its Repurchase Option or may exercise its
Repurchase Option only with respect to a portion of the Unvested Shares. 
 5.4 Right of Termination Unaffected. Nothing in
this Agreement shall be construed to limit or otherwise affect in any manner whatsoever the right or power of the Company (or any Parent or Subsidiary of the Company) to terminate Purchaser’s employment or other relationship with Company (or
the Parent or Subsidiary of the Company) at any time, for any reason or no reason, with or without Cause. 

  
 4 

 5.5 Additional or Exchanged Securities and Property. Subject to the provisions of
Section 5.2 above, in the event of a merger or consolidation of the Company with or into another entity, any other corporate reorganization, a stock split, the declaration of a stock dividend, the declaration of an extraordinary dividend
payable in a form other than stock, a spin-off, a recapitalization or a similar transaction affecting the Company’s outstanding securities, any securities or other property (including cash or cash
equivalents) that are by reason of such transaction exchanged for, or distributed or issued with respect to, any Unvested Shares shall immediately be subject to the Repurchase Option. Appropriate adjustments shall be made to the price per share to
be paid for Unvested Shares upon the exercise of the Repurchase Option (by allocating such price among the Unvested Shares and such other securities or property), provided that the aggregate purchase price payable for the Unvested
Shares and all such other securities and property shall remain the same price that was original payable under the Repurchase Option to repurchase such Unvested Shares. Subject to the provisions of Section 5.2 above, in the event of a merger or
consolidation of the Company with or into another entity or any other corporate reorganization, the Repurchase Option may be exercised by the Company’s successor. 

5.6 Assignment of Repurchase Right. The Company may freely assign the Company’s Repurchase Option, in whole or in part,
provided that any person who accepts an assignment of the Repurchase Option from the Company shall assume all of the Company’s rights and obligations with respect to the Repurchase Option (to the extent so assigned) under this Agreement. 

6. COMPANY’S REFUSAL RIGHT. Unvested Shares shall be subject to the restrictions on transfer and the granting of encumbrances
thereon as provided in Section 7 hereof. Before any Vested Shares (as defined in Section 5 hereof) held by Purchaser or any transferee of such Vested Shares (either sometimes referred to herein as the “Holder”) may
be sold or otherwise transferred (including, without limitation, a transfer by gift or operation of law), the Company and/or its assignee(s) will have a right of first refusal to purchase the Vested Shares to be sold or transferred (the
“Offered Shares”) on the terms and conditions set forth in this Section (the “Refusal Right”). 

6.1 Notice of Proposed Transfer. The Holder of the Offered Shares will deliver to the Company a written notice (the
“Notice”) stating: (a) the Holder’s bona fide intention to sell or otherwise transfer the Offered Shares; (b) the name and address of each proposed purchaser or other transferee of Offered Shares
(“Proposed Transferee”); (c) the number of Offered Shares to be transferred to each Proposed Transferee; (d) the bona fide cash price or other consideration for which the Holder proposes to transfer the Offered
Shares to each Proposed Transferee (the “Offered Price”); and (e) that the Holder acknowledges this Notice is an offer to sell the Offered Shares to the Company and/or its assignee(s) pursuant to the Company’s
Refusal Right at the Offered Price as provided for in this Agreement. 
 6.2 Exercise of Refusal Right. At any time within
thirty (30) days after the date the Notice is effective pursuant to Section 9.2, the Company and/or its assignee(s) may, by giving written notice to the Holder, elect to purchase all (or, with the consent of the Holder, less than all) the
Offered Shares proposed to be transferred to any one or more of the Proposed Transferees named in the Notice, at the purchase price, determined as provided in Section 6.3 below. 

6.3 Purchase Price. The purchase price for the Offered Shares purchased under this Section will be the Offered Price,
provided that if the Offered Price consists of no legal consideration (as, for example, in the case of a transfer by gift), then the purchase price will be the fair market value of the Offered Shares as determined in good faith by the
Company’s Board of Directors. If the Offered Price includes consideration other than cash, then the value of the non-cash consideration, as determined in good faith by the Company’s Board of Directors, will conclusively be deemed to be the
cash equivalent value of such non-cash consideration. 

  
 5 

 6.4 Payment. The purchase price for the Offered Shares will be paid, at the option
of the Company and/or its assignee(s) (as applicable), by check or by cancellation of all or a portion of any outstanding indebtedness owed by the Holder to the Company (or to such assignee, in the case of a purchase of Offered Shares by such
assignee) or by any combination thereof. The purchase price will be paid without interest within sixty (60) days after the Company’s receipt of the Notice, or, at the option of the Company and/or its assignee(s), in the manner and at the
time(s) set forth in the Notice. 
 6.5 Holder’s Right to Transfer. If all of the Offered Shares proposed in the Notice
to be transferred to a given Proposed Transferee are not purchased by the Company and/or its assignee(s) as provided in this Section, then the Holder may sell or otherwise transfer such Offered Shares to such Proposed Transferee at the Offered Price
or at a higher price, provided that (a) such sale or other transfer is consummated within one hundred twenty (120) days after the date the Notice is effective pursuant to Section 9.2, (b) any such sale or other
transfer is effected in compliance with all applicable securities laws, and (c) such Proposed Transferee agrees in writing that the provisions of this Section will continue to apply to the Offered Shares in the hands of such Proposed
Transferee. If the Offered Shares described in the Notice are not transferred to such Proposed Transferee within such one hundred twenty (120) day period, then a new Notice must be given to the Company pursuant to which the Company will again
be offered the Refusal Right before any Shares held by the Holder may be sold or otherwise transferred. 
 6.6 Exempt
Transfers. Notwithstanding the foregoing, the following transfers of Vested Shares will be exempt from the Refusal Right: (a) the transfer of any or all of the Vested Shares during Purchaser’s lifetime by gift or on
Purchaser’s death by will or intestacy to Purchaser’s “Immediate Family” (as defined below) or to a trust for the benefit of Purchaser or Purchaser’s Immediate Family, provided that each transferee agrees in a
writing satisfactory to the Company that the provisions of this Section will continue to apply to the transferred Vested Shares in the hands of such transferee; (b) any transfer of Vested Shares made pursuant to a statutory merger or statutory
consolidation of the Company with or into another entity or entities (except that, subject to Section 6.7, unless the agreement of merger or consolidation expressly otherwise provides, the Refusal Right will continue to apply thereafter to such
Vested Shares, in which case the surviving entity of such merger or consolidation shall succeed to the rights of the Company under this Section); or (c) any transfer of Vested Shares pursuant to the winding up and dissolution of the Company. As
used herein, the term “Immediate Family” will mean Purchaser’s spouse, the lineal descendant or antecedent, father, mother, brother or sister, child, adopted child, grandchild or adopted grandchild of
Purchaser or Purchaser’s spouse, or the spouse of any of the above or Spousal Equivalent, as defined herein. As used herein, a person is deemed to be a “Spousal Equivalent” provided the following
circumstances are true: (i) irrespective of whether or not the Purchaser and the Spousal Equivalent are the same sex, they are the sole spousal equivalent of the other for the last twelve (12) months, (ii) they intend to remain so
indefinitely, (iii) neither are married to anyone else, (iv) both are at least 18 years of age and mentally competent to consent to contract, (v) they are not related by blood to a degree of closeness that which would prohibit legal
marriage in the state in which they legally reside, (vi) they are jointly responsible for each other’s common welfare and financial obligations, and (vii) they reside together in the same residence for the last twelve (12) months
and intend to do so indefinitely. 
 6.7 Termination of Refusal Right. The Refusal Right will terminate as to all Shares:
(a) on the effective date of the first sale of Common Stock of the Company to the public pursuant to a registration statement filed with and declared effective by the SEC under the Securities Act or, if expressly approved by the Board as
terminating the Refusal Right, under the laws of any other country having substantially the same effect (other than a registration statement relating solely to the issuance of Common Stock pursuant to a business combination or an employee incentive
or benefit plan) or (b) on any transfer or conversion of Shares made pursuant to a statutory merger or statutory consolidation of the Company with or into another entity or entities if the common stock of the surviving entity or any direct or
indirect parent entity thereof is registered under the Securities Exchange Act of 1934, as amended. 

  
 6 

 7. ADDITIONAL RESTRICTIONS UPON SHARE OWNERSHIP OR TRANSFER. 

7.1 Rights as a Stockholder. Subject to the terms and conditions of this Agreement, Purchaser will have all of the rights of a
Stockholder of the Company with respect to the Shares from and after the date that Shares are issued to Purchaser until such time as Purchaser disposes of the Shares or the Company and/or its assignee(s) exercise(s) the Refusal Right or the
Repurchase Option. Upon an exercise of the Refusal Right or the Repurchase Option, Purchaser will have no further rights as a holder of the Shares so purchased upon such exercise, other than the right to receive payment for the Shares so purchased
in accordance with the provisions of this Agreement, and Purchaser will promptly surrender the stock certificate(s) evidencing the Shares so purchased to the Company for transfer or cancellation. 

7.2 Escrow. As security for Purchaser’s faithful performance of this Agreement, Purchaser agrees, immediately upon receipt
of the stock certificate(s) evidencing the Shares, to deliver such certificate(s) to the Secretary of the Company or other designee of the Company (the “Escrow Holder”), who is hereby appointed to hold such certificate(s) in
escrow and to take all such actions and to effectuate all such transfers and/or releases of such Shares as are in accordance with the terms of this Agreement. Purchaser and the Company agree that Escrow Holder will not be liable to any party to this
Agreement (or to any other person or entity) for any actions or omissions unless Escrow Holder is grossly negligent or intentionally fraudulent in carrying out the duties of Escrow Holder under this Agreement. Escrow Holder may rely upon any letter,
notice or other document executed with any signature purported to be genuine and may rely on the advice of counsel and obey any order of any court with respect to the transactions contemplated by this Agreement. The Shares will be released from
escrow upon termination of both the Refusal Right and the Repurchase Option. 
 7.3 Encumbrances on Shares. Without the
Company’s prior written consent given with the approval of the Company’s Board of Directors, Purchaser may not grant a lien or security interest in, or pledge, hypothecate or encumber, any Unvested Shares. 

7.4 Restrictions on Transfers. Unvested Shares may not be sold or otherwise transferred by Purchaser without the Company’s
prior written consent. Purchaser hereby agrees that Purchaser shall make no disposition of the Shares (other than as permitted by this Agreement) unless and until: 

(a) Purchaser shall have notified the Company of the proposed disposition and provided a written summary of the terms and
conditions of the proposed disposition; 
 (b) Purchaser shall have complied with all requirements of this Agreement
applicable to the disposition of the Shares, including but not limited to the Refusal Right, the Market Standoff and the Repurchase Option; and 

(c) Purchaser shall have provided the Company with written assurances, in form and substance satisfactory to counsel for the
Company, that (i) the proposed disposition does not require registration of the Shares under the Securities Act or under any state securities laws, and (ii) all appropriate actions necessary for compliance with the registration and
qualification requirements of the Securities Act and any state securities laws, or of any exemption from registration or qualification, available thereunder (including Rule 144) have been taken. 

Each person (other than the Company) to whom the Shares are transferred by means of one of the permitted transfers specified in this Agreement must, as a
condition precedent to the validity of such transfer, acknowledge in writing to the Company that such person is bound by the provisions of this Agreement and that the transferred Shares are subject to the Company’s Refusal Right or the
Repurchase Option granted hereunder and the market stand-off provisions of Section 4 hereof, to the same extent such Shares would be so subject if retained by the Purchaser. 

  
 7 

 7.5 Restrictive Legends and Stop-transfer Orders. Purchaser understands and agrees
that the Company will place the legends set forth below or similar legends on any stock certificate(s) evidencing the Shares, together with any other legends that may be required by applicable laws, the Company’s Certificate of Incorporation or
Bylaws, any other agreement between Purchaser and the Company or any agreement between Purchaser and any third party: 
 THE SECURITIES
REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR UNDER THE SECURITIES LAWS OF CERTAIN STATES. THESE SECURITIES ARE SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AND RESALE AND
MAY NOT BE TRANSFERRED OR RESOLD EXCEPT AS PERMITTED UNDER THE SECURITIES ACT AND APPLICABLE STATE SECURITIES LAWS, PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM. INVESTORS SHOULD BE AWARE THAT THEY MAY BE REQUIRED TO BEAR THE FINANCIAL RISKS OF
THIS INVESTMENT FOR AN INDEFINITE PERIOD OF TIME. THE ISSUER OF THESE SECURITIES MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND SUBSTANCE SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN COMPLIANCE WITH THE
SECURITIES ACT AND ANY APPLICABLE STATE SECURITIES LAWS. 
 THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN
RESTRICTIONS ON PUBLIC RESALE AND TRANSFER, INCLUDING THE RIGHT OF FIRST REFUSAL AND THE REPURCHASE OPTION HELD BY THE ISSUER AND/OR ITS ASSIGNEE(S), AND A MARKET STANDOFF AGREEMENT, AS SET FORTH IN A RESTRICTED STOCK PURCHASE AGREEMENT BETWEEN THE
ISSUER AND THE ORIGINAL HOLDER OF THESE SHARES, A COPY OF WHICH MAY BE OBTAINED AT THE PRINCIPAL OFFICE OF THE ISSUER. SUCH PUBLIC SALE AND TRANSFER RESTRICTIONS INCLUDING THE RIGHT OF FIRST REFUSAL, THE REPURCHASE OPTION AND THE MARKET STANDOFF ARE
BINDING ON TRANSFEREES OF THESE SHARES. 
 Purchaser also agrees that, to ensure compliance with the restrictions imposed by this Agreement, the Company
may issue appropriate “stop-transfer” instructions to its transfer agent, if any, and if the Company transfers its own securities, it may make appropriate notations to the same effect in its own records. The Company will not be required
(a) to transfer on its books any Shares that have been sold or otherwise transferred in violation of any of the provisions of this Agreement or (b) to treat as owner of such Shares, or to accord the right to vote or pay dividends to any
purchaser or other transferee to whom such Shares have been so transferred. 
 8. TAX CONSEQUENCES. PURCHASER UNDERSTANDS
THAT PURCHASER MAY SUFFER ADVERSE TAX CONSEQUENCES AS A RESULT OF PURCHASER’S PURCHASE OR DISPOSITION OF THE SHARES. PURCHASER REPRESENTS (a) THAT PURCHASER HAS CONSULTED WITH ANY TAX ADVISER THAT PURCHASER DEEMS ADVISABLE IN CONNECTION
WITH THE PURCHASE OR DISPOSITION OF THE SHARES AND (b) THAT PURCHASER IS NOT RELYING ON THE COMPANY FOR ANY TAX ADVICE. Purchaser hereby acknowledges that Purchaser has been informed that, with respect to Unvested Shares, unless an election
is filed by Purchaser with the Internal Revenue Service (and, if necessary, the proper state taxing authorities) within 30 days after the purchase of the Shares electing, pursuant to Section 83(b) of the Internal Revenue Code (and
similar state tax provisions, if applicable), to be taxed currently on any difference between the Purchase Price of 

  
 8 

 
the Unvested Shares and their Fair Market Value on the date of purchase, there will be a recognition of taxable income to Purchaser, measured by the excess, if any, of the Fair Market Value of
the Unvested Shares, at the time they cease to be Unvested Shares, over the Purchase Price for such Shares. Purchaser represents that Purchaser has consulted any tax advisers Purchaser deems advisable in connection with Purchaser’s purchase of
the Shares and the filing of the election under Section 83(b) and similar tax provisions. A form of Election under Section 83(b) is attached hereto as Exhibit 1 for reference. BY PROVIDING THE FORM OF ELECTION,
NEITHER THE COMPANY NOR ITS LEGAL COUNSEL IS THEREBY UNDERTAKING TO FILE THE ELECTION FOR PURCHASER, WHICH OBLIGATION TO FILE SHALL REMAIN SOLELY WITH PURCHASER. 

9. GENERAL PROVISIONS. 

9.1 Successors and Assigns. The Company may assign any of its rights under this Agreement, including its rights to purchase
Shares under the Refusal Right or the Repurchase Option. Neither Purchaser, nor any of Purchaser’s successors and assigns, may assign, whether voluntarily or by operation of law, any of its rights and obligations under this Agreement, except
with the prior written consent of the Company. This Agreement shall be binding upon and inure to the benefit of the successors and assigns of the Company. Subject to the restrictions on transfer herein set forth, this Agreement will be binding upon
Purchaser and Purchaser’s heirs, executors, administrators, legal representatives, successors and assigns. 
 9.2
Notices. Any and all notices required or permitted to be given to a party pursuant to the provisions of this Agreement will be in writing and will be effective and deemed to provide such party sufficient notice under this Agreement on the
earliest of the following: (i) at the time of personal delivery, if delivery is in person; (ii) at the time an electronic confirmation of receipt is received, if delivery is by email; (iii) at the time of transmission by facsimile,
addressed to the other party at its facsimile number specified herein (or hereafter modified by subsequent notice to the parties hereto), with confirmation of receipt made by both telephone and printed confirmation sheet verifying successful
transmission of the facsimile; (iv) one (1) business day after deposit with an express overnight courier for United States deliveries, or two (2) business days after such deposit for deliveries outside of the United States, with proof
of delivery from the courier requested; or (v) three (3) business days after deposit in the United States mail by certified mail (return receipt requested) for United States deliveries. Any notice for delivery outside the United States
will be sent by email, facsimile or by express courier. Any notice not delivered personally or by email will be sent with postage and/or other charges prepaid and properly addressed to Purchaser at the last known address or facsimile number on the
books of the Company, or at such other address or facsimile number as such other party may designate by one of the indicated means of notice herein to the other parties hereto or, in the case of the Company, to it at its principal place of business.
Notices to the Company will be marked “Attention: Chief Financial Officer.” Notices by facsimile shall be machine verified as received. 

9.3 Further Assurances. The parties agree to execute such further documents and instruments and to take such further actions as
may be reasonably necessary to carry out the purposes and intent of this Agreement. 
 9.4 Entire Agreement. The Plan is
incorporated herein by reference. The Plan and this Agreement, together with all Exhibits hereto, constitute the entire agreement and understanding of the parties with respect to the subject matter of this Agreement, and supersede all prior
understandings and agreements, between the parties hereto with respect to the specific subject matter hereof. 
 9.5
Severability. If any provision of this Agreement is determined by any court or arbitrator of competent jurisdiction to be invalid, illegal or unenforceable in any respect, such provision will be enforced to the maximum extent possible
given the intent of the parties hereto. If such clause or 

  
 9 

 
provision cannot be so enforced, such provision shall be stricken from this Agreement and the remainder of this Agreement shall be enforced as if such invalid, illegal or unenforceable clause or
provision had (to the extent not enforceable) never been contained in this Agreement. Notwithstanding the forgoing, if the value of this Agreement based upon the substantial benefit of the bargain for any party is materially impaired, which
determination as made by the presiding court or arbitrator of competent jurisdiction shall be binding, then both parties agree to substitute such provision(s) through good faith negotiations. 

9.6 Execution. This Agreement may be entered into in two or more counterparts, each of which shall be deemed an original and all
of which shall constitute one and the same agreement. This Agreement may be executed and delivered by facsimile and, upon such delivery, the facsimile signature will be deemed to have the same effect as if the original signature had been delivered
to the other party. 
 [The remainder of this page has intentionally been left blank] 

[Signature page follows] 

  
 10 

 IN WITNESS WHEREOF, the Company has caused this Restricted Stock Purchase Agreement to be
executed by its duly authorized representative, and Purchaser has executed this Restricted Stock Purchase Agreement, as of the date first set forth above. 
  

									
	AEGLEA BIOTHERAPEUTICS, INC.	 		 	PURCHASER
				
	 By:
	 	  
	 		 	  

									
					
	 Address:
	 		 		 	Address:	 	  

		 		 		 		 	  

									
					
	Fax No.: (            )	 	  
	 		 	Fax No.: (            )	 	  

  

			
	 Exhibit
	  	 
	Exhibit 1:	  	        Form of Election Pursuant to Section 83(b)

  
 11 

 EXHIBIT 1 

FORM OF SECTION 83(B) ELECTION 

 ELECTION UNDER SECTION 83(b) OF THE 

INTERNAL REVENUE CODE 
 The undersigned
Taxpayer hereby elects, pursuant to Section 83(b) of the Internal Revenue Code of 1986, as amended, to include in gross income for the Taxpayer’s current taxable year the excess, if any, of the fair market value of the property described
below at the time of transfer over the amount paid for such property, as compensation for services. 
  

							
	1.		TAXPAYER’S NAME:		  
		
				
			TAXPAYER’S ADDRESS:		  
		
				
			SOCIAL SECURITY NUMBER:		  
		
				
			TAXABLE YEAR:		Calendar Year             		
		
	2.		The property with respect to which the election is made is described as follows:                 shares of Common Stock, par value $0.001
per share, of Aeglea BioTherapeutics, Inc., a Delaware corporation (the “Company”), which is Taxpayer’s employer or the corporation for whom the Taxpayer performs services.
		
	3.		The date on which the shares were transferred was                     ,
            .
		
	4.		The shares are subject to the following restrictions: The Company may repurchase all or a portion of the shares at the Taxpayer’s original purchase price under certain conditions at the time of Taxpayer’s
termination of employment or services.
		
	5.		The fair market value of the shares at the time of transfer (without regard to restrictions other than a nonlapse restriction as defined in § 1.83-3(h) of the Income Tax Regulations) was
$        per share x                 shares = $        .
		
	6.		The amount paid for such shares was $        per share x                 shares =
$        .
		
	7.		The amount to include in the Taxpayer’s gross income for the Taxpayer’s current taxable year is $        .

 THIS ELECTION MUST BE FILED WITH THE INTERNAL REVENUE SERVICE (“IRS”), AT THE OFFICE WHERE
THE TAXPAYER FILES ANNUAL INCOME TAX RETURNS, WITHIN 30 DAYS AFTER THE DATE OF TRANSFER OF THE PROPERTY, AND MUST ALSO BE FILED WITH THE TAXPAYER’S INCOME TAX RETURNS FOR THE CALENDAR YEAR. A COPY OF THE ELECTION HAS ALSO BEEN FURNISHED
TO THE COMPANY. THE ELECTION CANNOT BE REVOKED WITHOUT THE CONSENT OF THE IRS. 
  

							
	Dated:						  

							Taxpayer’s Signature

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00246-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00246-of-00352.parquet"}]]