240.13d-102 Schedule 13G - Information to be included in statements filed
pursuant to 240.13d-1(b), (c), and (d) and amendments thereto
filed pursuant to 240.13d-2.
Securities and Exchange Commission, Washington, D.C. 20549
Schedule 13G
Under the Securities Exchange Act of 1934
(Amendment No.)*
(Name of Issuer)
CymaBay Therapeutics, Inc.
(Title of Class of Securities)
Common Stock, Par Value $0.0001 Per Share

(CUSIP Number)

23257D103
(Date of Event Which Requires Filing of this Statement)
May 28, 2019

Check the appropriate box to designate the rule pursuant to which this
Schedule is filed:
[  ] Rule 13d-1(b)
[ x ] Rule 13d-1(c)
[  ] Rule 13d-1(d)
*The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be
deemed to be “filed” for the purpose of Section 18 of the Securities Exchange
Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the
Act but shall be subject to all other provisions of the Act (however, see
the Notes).



CUSIP No. 48576U106
(1) Names of reporting persons    Point72 Asset Management, L.P.
 
(2) Check the appropriate box if a member of a group
(a)
(see instructions)
(b)X
(3) SEC use only
 
(4) Citizenship or place of organization  Delaware
 
Number of shares beneficially owned by each reporting person with:
 
(5) Sole voting power                  0
 
(6) Shared voting power              4,307,900 (see Item 4)
 
(7) Sole dispositive power           0
 
(8) Shared dispositive power       4,307,900 (see Item 4)
 
(9) Aggregate amount beneficially owned by each reporting person
4,307,900 (see Item 4)
 
(10) Check if the aggregate amount in Row (9) excludes certain shares
(see instructions)
 
(11) Percent of class represented by amount in Row (9)     6.3% (see Item 4)
 
(12) Type of reporting person (see instructions)     PN
 


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CUSIP No. 23257D103
(1) Names of reporting persons    Point72 Capital Advisors, Inc.
 
(2) Check the appropriate box if a member of a group
(a)
(see instructions)
(b)X
(3) SEC use only
 
(4) Citizenship or place of organization  Delaware
 
Number of shares beneficially owned by each reporting person with:
 
(5) Sole voting power                  0
 
(6) Shared voting power              4,307,900 (see Item 4)
 
(7) Sole dispositive power           0
 
(8) Shared dispositive power       4,307,900 (see Item 4)
 
(9) Aggregate amount beneficially owned by each reporting person
4,307,900 (see Item 4)
 
(10) Check if the aggregate amount in Row (9) excludes certain shares
(see instructions)
 
(11) Percent of class represented by amount in Row (9)    6.3% (see Item 4)
 
(12) Type of reporting person (see instructions)     CO
 

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CUSIP No. 23257D103
(1) Names of reporting persons    Cubist Systematic Strategies, LLC
 
(2) Check the appropriate box if a member of a group
(a)
(see instructions)
(b)X
(3) SEC use only
 
(4) Citizenship or place of organization  Delaware
 
Number of shares beneficially owned by each reporting person with:
 
(5) Sole voting power                  0
 
(6) Shared voting power              21,095 (see Item 4)
 
(7) Sole dispositive power           0
 
(8) Shared dispositive power       21,095 (see Item 4)
 
(9) Aggregate amount beneficially owned by each reporting person
21,095 (see Item 4)
 
(10) Check if the aggregate amount in Row (9) excludes certain shares
(see instructions)
 
(11) Percent of class represented by amount in Row (9)   <0.1% (see Item 4)
 
(12) Type of reporting person (see instructions)     OO
 

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CUSIP No. 23257D103
(1) Names of reporting persons    Point72 Hong Kong Limited
 
(2) Check the appropriate box if a member of a group
(a)
(see instructions)
(b)X
(3) SEC use only
 
(4) Citizenship or place of organization  Hong Kong
 
Number of shares beneficially owned by each reporting person with:
 
(5) Sole voting power                  0
 
(6) Shared voting power              747 (see Item 4)
 
(7) Sole dispositive power           0
 
(8) Shared dispositive power       747 (see Item 4)
 
(9) Aggregate amount beneficially owned by each reporting person
747 (see Item 4)
 
(10) Check if the aggregate amount in Row (9) excludes certain shares
(see instructions)
 
(11) Percent of class represented by amount in Row (9)   <0.1% (see Item 4)
 
(12) Type of reporting person (see instructions)     OO
 

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CUSIP No. 23257D103
(1) Names of reporting persons    Steven A. Cohen
 
(2) Check the appropriate box if a member of a group
(a)
(see instructions)
(b)X
(3) SEC use only
 
(4) Citizenship or place of organization  United States
 
Number of shares beneficially owned by each reporting person with:
 
(5) Sole voting power                  0
 
(6) Shared voting power              4,329,742 (see Item 4)
 
(7) Sole dispositive power           0
 
(8) Shared dispositive power       4,329,742 (see Item 4)
 
(9) Aggregate amount beneficially owned by each reporting person
4,329,742 (see Item 4)
 
(10) Check if the aggregate amount in Row (9) excludes certain shares
(see instructions)
 
(11) Percent of class represented by amount in Row (9)  6.3% (see Item 4)
 
(12) Type of reporting person (see instructions)     IN
 

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Item 1(a) Name of issuer:
CymaBay Therapeutics, Inc.
Item 1(b) Address of issuer's principal executive offices:
7575 Gateway Blvd., Suite 110, Newark, CA 94560
2(a) Name of person filing:
This statement is filed by: (i) Point72 Asset Management, L.P. (“Point72 Asset
Management”) with respect to shares of common stock, par value $0.0001 per
share (“Shares”), of the Issuer held by certain investment funds it manages;
(ii) Point72 Capital Advisors, Inc. (“Point72 Capital Advisors Inc.”) with
respect to Shares held by certain investment funds managed by Point72 Asset
Management; (iii) Cubist Systematic Strategies, LLC (“Cubist Systematic
Strategies”) with respect to Shares held by certain investment funds it
manages; (iv) Point72 Hong Kong Limited (“Point72 Hong Kong”)
with respect to Shares held by certain investment funds it manages; and (v)
Steven A. Cohen (“Mr. Cohen”) with respect to Shares beneficially owned by
Point72 Asset Management, Point72 Capital Advisors Inc., Cubist Systematic
Strategies, and Point72 Hong Kong.
Point72 Asset Management, Point72 Capital Advisors Inc., Cubist Systematic
Strategies, Point72 Hong Kong, and Mr. Cohen have entered into a Joint Filing
Agreement, a copy of which is filed with this Schedule 13G as Exhibit 99.1,
pursuant to which they have agreed to file this Schedule 13G jointly in
accordance with the provisions of Rule 13d-1(k) of the Act.

2(b) Address or principal business office or, if none, residence:
The address of the principal business office of (i) Point72 Asset Management,
Point72 Capital Advisors Inc., and Mr. Cohen is 72 Cummings Point Road,
Stamford, CT 06902; (ii) Cubist Systematic Strategies is 330 Madison Avenue,
New York, NY 10017; and (iii) Point72 Hong Kong is 12th Floor, Chater House,

8 Connaught Central, Hong Kong.
2(c) Citizenship:
Point72 Asset Management is a Delaware limited partnership. Point72 Capital
Advisors Inc. is a Delaware corporation. Cubist Systematic Strategies is a Delaware

limited liability company. Point72 Hong Kong is a Hong Kong limited liability

company. Mr. Cohen is a United States citizen.
2(d) Title of class of securities:
Common Stock, Par Value $0.0001 Per Share
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2(e) CUSIP Number:
23257D103

Item 3.

Not applicable

Item 4. Ownership

As of the close of business on June 6, 2019:

1. Point72 Asset Management, L.P.
(a) Amount beneficially owned: 4,307,900
(b) Percent of class: 6.3%          
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 4,307,900          
(iii) Sole power to dispose or to direct the disposition of: 0
(iv) Shared power to dispose or to direct the disposition of: 4,307,900

2. Point72 Capital Advisors, Inc.
(a) Amount beneficially owned: 4,307,900
(b) Percent of class: 6.3%          
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 4,307,900          
(iii) Sole power to dispose or to direct the disposition of: 0
(iv) Shared power to dispose or to direct the disposition of: 4,307,900

3. Cubist Systematic Strategies, LLC
(a) Amount beneficially owned: 21,095
(b) Percent of class: <0.1%          
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 21,095          
(iii) Sole power to dispose or to direct the disposition of: 0
(iv) Shared power to dispose or to direct the disposition of: 21,095

4. Point72 Hong Kong Limited
(a) Amount beneficially owned: 747
(b) Percent of class: <0.1%          
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 747          
(iii) Sole power to dispose or to direct the disposition of: 0
(iv) Shared power to dispose or to direct the disposition of: 747

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5. Steven A. Cohen
(a) Amount beneficially owned: 4,329,742
(b) Percent of class: 6.3%          
(c) Number of shares as to which the person has:
(i) Sole power to vote or to direct the vote: 0
(ii) Shared power to vote or to direct the vote: 4,329,742          
(iii) Sole power to dispose or to direct the disposition of: 0
(iv) Shared power to dispose or to direct the disposition of: 4,329,742
Point72 Asset Management, Point72 Capital Advisors Inc., Cubist Systematic
Strategies, Point72 Hong Kong, and Mr. Cohen own directly no Shares.
Pursuant to an investment management agreement, Point72 Asset Management
maintains investment and voting power with respect to the securities held by
certain investment funds it manages. Point72 Capital Advisors Inc. is the
general partner of Point72 Asset Management. Pursuant to an investment
management agreement, Cubist Systematic Strategies maintains investment and
voting power with respect to the securities held by certain investment funds
it manages. Pursuant to an investment management agreement, Point72 Hong
Kong maintains investment and voting power with respect to the securities
held by certain investment funds it manages. Mr. Cohen controls each of
Point72 Asset Management, Point72 Capital Advisors Inc., Cubist Systematic
Strategies, and Point72 Hong Kong.  By reason of the provisions of Rule 13d-3

of the Securities Exchange Act of 1934, as amended, each of (i) Point72 Asset

Management, Point72 Capital Advisors Inc., and Mr. Cohen may be deemed to

beneficially own 4,307,900 Shares (constituting approximately 6.3% of the

Shares outstanding); (ii) Cubist Systematic Strategies and Mr. Cohen may be

deemed to beneficially own 21,095 Shares (constituting <0.1% of the Shares

outstanding); and (iii) Point72 Hong Kong and Mr. Cohen may be deemed to

beneficially own 747 Shares (constituting <0.1% of the Shares outstanding).  

Each of Point72 Asset Management, Point72 Capital Advisors Inc., Cubist

Systematic Strategies, Point72 Hong Kong, and Mr. Cohen disclaims beneficial

ownership of any of the securities covered by this statement.
Item 5.  Ownership of 5 Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof
the reporting person has ceased to be the beneficial owner of more than
5 percent of the class of securities, check the following [].

Item 6.  Ownership of More than 5 Percent on Behalf of Another Person.

Not applicable

Item 7.  Identification and Classification of the Subsidiary Which Acquired
the Security Being Reporting on by the Parent Holding Company or Control
Person.
Not applicable
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Item 8.  Identification and Classification of Members of the Group
Not applicable

Item 9.  Notice of Dissolution of Group.

Not applicable

Item 10. Certifications

By signing below I certify that, to the best of his/her knowledge and belief,
the securities referred to above were not acquired and are not held for the purpose
of or with the effect of changing or influencing the control of the issuer of
the securities and were not acquired and are not held in connection with or
as a participant in any transaction having that purpose or effect.

Signature.  After reasonable inquiry and to the best of my knowledge and belief,
I certify that the information set forth in this statement is true, complete
and correct.
Dated: June 7, 2019
POINT72 ASSET MANAGEMENT, L.P.
By: /s/ Jason M. Colombo
Name: Jason M. Colombo
Title: Authorized Person

POINT72 CAPITAL ADVISORS, INC.
By: /s/ Jason M. Colombo
Name: Jason M. Colombo
Title: Authorized Person

CUBIST SYSTEMATIC STRATEGIES, LLC
By: /s/ Jason M. Colombo
Name: Jason M. Colombo
Title: Authorized Person

POINT72 HONG KONG LIMITED
By: /s/ Jason M. Colombo
Name: Jason M. Colombo
Title: Authorized Person

STEVEN A. COHEN
By: /s/ Jason M. Colombo
Name: Jason M. Colombo
Title: Authorized Person

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