(Amendment No. 1)
Check the appropriate box to designate the rule pursuant
to which this Schedule is filed:
* 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 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.
28249H104
|
13G/A
|
Page
2
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES
ONLY)
Viking Global Investors LP
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
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
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
PN
|
|
|
|
|
|
|
CUSIP No. 28249H104
|
13G/A
|
Page
3
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES
ONLY)
Viking Global Opportunities GP LLC
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
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
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
OO
|
|
|
|
|
|
|
CUSIP No. 28249H104
|
13G/A
|
Page
4
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES
ONLY)
Viking Global Opportunities Portfolio GP LLC
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
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
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
OO
|
|
|
|
|
|
|
CUSIP No.
28249H104
|
13G/A
|
Page
5
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES
ONLY)
Viking Global Opportunities Liquid Portfolio Sub-Master LP
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
3
|
SEC USE ONLY
|
4
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Cayman Islands
|
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE VOTING POWER
0
|
6
|
SHARED VOTING POWER
882,353
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
882,353
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
882,353
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
2.4%
|
12
|
TYPE OF REPORTING PERSON
PN
|
|
|
|
|
|
|
CUSIP No.
28249H104
|
13G/A
|
Page
6
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Viking Global Opportunities Illiquid Investments Sub-Master LP
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
3
|
SEC USE ONLY
|
4
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Cayman Islands
|
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE VOTING POWER
0
|
6
|
SHARED VOTING POWER
1,103,848
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,103,848
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,103,848
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
3.0%
|
12
|
TYPE OF REPORTING PERSON
*
PN
|
|
|
|
|
|
|
CUSIP No.
28249H104
|
13G/A
|
Page
7
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
O. Andreas Halvorsen
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
3
|
SEC USE ONLY
|
4
|
CITIZENSHIP OR PLACE OF ORGANIZATION
Norway
|
NUMBER OF
SHARES
BENEFICIALLY
OWNED BY
EACH
REPORTING
PERSON
WITH
|
5
|
SOLE VOTING POWER
0
|
6
|
SHARED VOTING POWER
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
*
IN
|
|
|
|
|
|
|
CUSIP No.
28249H104
|
13G/A
|
Page
8
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
David C. Ott
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
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
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
*
IN
|
|
|
|
|
|
|
CUSIP No.
28249H104
|
13G/A
|
Page
9
of
17
Pages
|
1
|
NAME OF REPORTING PERSON
I.R.S. IDENTIFICATION NO. OF ABOVE PERSON (ENTITIES ONLY)
Rose S. Shabet
|
2
|
CHECK THE APPROPRIATE BOX IF A MEMBER
OF A GROUP
*
(a)
☐
(b)
☒
|
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
1,986,201
|
7
|
SOLE DISPOSITIVE POWER
0
|
8
|
SHARED DISPOSITIVE POWER
1,986,201
|
9
|
AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
1,986,201
|
10
|
CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES
*
☐
|
11
|
PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
5.4%
|
12
|
TYPE OF REPORTING PERSON
*
IN
|
|
|
|
|
|
|
Item 1(a)
.
Name of Issuer
:
Eidos Therapeutics, Inc.
Item 1(b)
.
Address of Issuer’s Principal Executive Offices
:
101 Montgomery Street, Suite 2550
San Francisco, CA 94104
Item 2(a)
.
Name of Person Filing
:
Viking Global Investors LP (“VGI”),
Viking Global Opportunities GP LLC (“Opportunities
GP”),
Viking Global Opportunities Portfolio GP LLC (“Opportunities
Portfolio GP”),
Viking Global Opportunities Liquid Portfolio Sub-Master
LP ("VGOL”),
Viking Global Opportunities Illiquid Investments
Sub-Master LP ("VGOP"),
O. Andreas Halvorsen, David C. Ott and
Rose S. Shabet (collectively, the "Reporting Persons")
Items 2(b)
.
Address of Principal Business Office
or, if none, Residence
:
The business address of each of the Reporting
Persons is: 55 Railroad Avenue, Greenwich, Connecticut 06830.
Items 2(c)
.
Citizenship
:
VGI is a Delaware limited partnership;
Opportunities GP and Opportunities Portfolio GP are Delaware limited liability companies; VGOL and VGOP are Cayman Islands exempted
limited partnerships; O. Andreas Halvorsen is a citizen of Norway; and David C. Ott and Rose S. Shabet are citizens of the United
States.
Item 2(d)
.
Titles of Classes of Securities
:
Common stock, par value $0.001 per share (“Common Stock”)
Item 2(e)
. CUSIP NUMBER: 28249H104
Item 3
.
If This Statement is Filed Pursuant
to Rule 13d-1(b), or 13d-2(b) or
(c), Check Whether the Person Filing is a
:
|
(a)
|
[ ] Broker or dealer registered under Section 15 of the Exchange Act
|
|
(b)
|
[ ] Bank as defined in Section 3(a)(6) of the Exchange Act
|
|
(c)
|
[ ] Insurance company as defined in Section 3(a)(19) of the Exchange Act
|
|
(d)
|
[ ] Investment company registered under Section 8 of the Investment
Company Act of 1940
|
|
(e)
|
[ ] Investment Adviser registered under Section 203 of the Investment Advisers Act of 1940: see Rule 13d-1(b)(1)(ii)(E)
|
|
(f)
|
[ ] Employee Benefit Plan, Pension Fund which is subject to the provisions of the Employee Retirement Income Security Act of
1974 or Endowment Fund; see Rule 13d-1(b)(1)(ii)(F)
|
|
(g)
|
[ ] Parent holding company, in accordance with Rule 13d-1(b)(1)(ii)(G).
|
|
(h)
|
[ ] Savings Association as defined in Section 3(b) of the Federal Deposit Insurance Act.
|
|
(i)
|
[ ] Church Plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company
Act of 1940.
|
|
(j)
|
[ ] Non-U.S. institution in accordance with Rule 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance
with Rule 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
|
|
(k)
|
[ ] Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
|
Item 4
.
Ownership
A. VGI
|
(a)
|
Amount beneficially owned: 1,986,201
|
|
(b)
|
Percent of Class: 5.4%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 1,986,201
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 1,986,201
|
VGI provides managerial services to VGOL and VGOP.
VGI has the authority to dispose of and vote the shares of Common Stock.
Based on Rule 13d-3 of the Securities Exchange Act
of 1934, as amended (the "Act"), VGI may be deemed to beneficially own the shares of Common Stock directly held by VGOL
and VGOP. VGI does not directly own any shares of Common Stock.
VGI beneficially owns 1,986,201 shares of Common Stock
consisting of (i) 882,353 shares of Common Stock directly and beneficially owned by VGOL
and (ii) 1,103,848 shares of Common Stock directly
and beneficially owned by VGOP.
B. Opportunities GP
|
(a)
|
Amount beneficially owned: 1,986,201
|
|
(b)
|
Percent of Class: 5.4%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 1,986,201
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 1,986,201
|
Opportunities GP serves as the sole member of Opportunities
Portfolio GP and has the authority to dispose of and vote the shares of Common Stock controlled by Opportunities Portfolio GP,
which consists of the shares of Common Stock directly held by VGOL and VGOP. Opportunities GP does not directly own any shares
of Common Stock.
Based on Rule 13d-3 of the Act, Opportunities GP may
be deemed to beneficially own the shares of Common Stock directly held by VGOL and VGOP.
Opportunities GP beneficially owns 1,986,201 shares
of Common Stock consisting of (i) 882,353 shares of Common Stock directly and beneficially owned by VGOL and (ii) 1,103,848 shares
of Common Stock directly and beneficially owned by VGOP.
C. Opportunities Portfolio GP
|
(a)
|
Amount beneficially owned: 1,986,201
|
|
(b)
|
Percent of Class: 5.4%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 1,986,201
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 1,986,201
|
Opportunities Portfolio GP serves as the general partner
of VGOL and VGOP and has the authority to dispose of and vote the shares of Common Stock directly owned by VGOL and VGOP. Opportunities
Portfolio GP does not directly own any shares of Common Stock.
Based on Rule 13d-3 of the Act, Opportunities Portfolio
GP may be deemed to beneficially own the shares of Common Stock directly held by VGOL and VGOP.
Opportunities Portfolio GP beneficially owns 1,986,201
shares of Common Stock consisting of (i) 882,353 shares of Common Stock directly and beneficially owned by VGOL and (ii) 1,103,848
shares of Common Stock directly and beneficially owned by VGOP.
D. VGOL
|
(a)
|
Amount beneficially owned: 882,353
|
|
(b)
|
Percent of Class: 2.4%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 882,353
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 882,353
|
VGOL has the authority to dispose of and vote the shares
of Common Stock directly owned by it, which power may be exercised by its general partner, Opportunities Portfolio GP, and by VGI,
an affiliate of Opportunities Portfolio GP, which provides managerial services to VGOL. Viking Global Opportunities LP (a Delaware
limited partnership) and Viking Global Opportunities III LP (a Cayman Islands exempted limited partnership), through its investment
in Viking Global Opportunities Intermediate LP (a Cayman Islands exempted limited partnership), invest substantially all of their
assets in Viking Global Opportunities Master LP (a Cayman Islands exempted limited partnership), which in turn invests through
VGOL.
E. VGOP
|
(a)
|
Amount beneficially owned: 1,103,848
|
|
(b)
|
Percent of Class: 3.0%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 1,103,848
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 1,103,848
|
VGOP has the authority to dispose of and vote the shares
of Common Stock directly owned by it, which power may be exercised by its general partner,
Opportunities Portfolio GP, and by VGI, an affiliate
of Opportunities Portfolio GP, which provides managerial services to VGOP. Viking Global Opportunities LP (a Delaware limited partnership)
and Viking Global Opportunities III LP (a Cayman Islands exempted limited partnership), through its investment in Viking Global
Opportunities Intermediate LP (a Cayman Islands exempted limited partnership), invest substantially all of their assets in Viking
Global Opportunities Master LP (a Cayman Islands exempted limited partnership), which in turn invests through VGOP.
F. O. Andreas Halvorsen, David C. Ott
and Rose S. Shabet
|
(a)
|
Amount beneficially owned: 1,986,201
|
|
(b)
|
Percent of Class: 5.4%
|
|
(c)
|
Number of shares as to which such person has:
|
|
(i)
|
Sole power to vote or to direct the vote: 0
|
|
(ii)
|
Shared power to vote or to direct the vote: 1,986,201
|
|
(iii)
|
Sole power to dispose or to direct the disposition of: 0
|
|
(iv)
|
Shared power to dispose or to direct the disposition of: 1,986,201
|
Mr. Halvorsen, Mr. Ott and Ms. Shabet, as Executive
Committee Members of Viking Global Partners LLC, general partner of VGI and Opportunities GP have shared authority to dispose of
and vote the shares of Common Stock beneficially owned by VGI and Opportunities GP. None of Mr. Halvorsen, Mr. Ott and Ms. Shabet
directly owns any shares of Common Stock.
Based on Rule 13d-3 of the Act, each may be deemed
to beneficially own the shares of Common Stock directly held by VGOL and VGOP.
Mr. Halvorsen, Mr. Ott and Ms. Shabet each beneficially
own 1,986,201 shares of Common Stock consisting of (i) 882,353 shares of Common Stock directly and beneficially owned by VGOL and
(ii) 1,103,848 shares of Common Stock directly and beneficially owned by VGOP.
Item 5
.
Ownership of Five Percent or Less of a Class.
If this statement is being filed to report
the fact that as of the date hereof the Reporting Persons have ceased to be the beneficial owner of more than five percent of the
class of securities, check the following [ ].
Item 6
.
Ownership of More than Five Percent on Behalf
of Another Person.
Yes, see Item 4.
Item 7
.
Identification and Classification of the Subsidiary
Which Acquired the Security
Being Reported on by the Parent Holding Company.
Not applicable.
Item 8
.
Identification and Classification of Members
of the Group.
Not applicable.
Item 9
.
Notice of Dissolution of Group.
Not applicable
Item 10
.
Certification.
(if filing pursuant to Rule 13d-1(c))
By signing below each Reporting Person
certifies that, to the best of its 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 not held in connection with or as a participant in any transaction having that purpose or effect.
SIGNATURES
After reasonable inquiry and to the best of our knowledge
and belief, the undersigned certify that the information set forth in this statement is true, complete and correct.
Dated: January 10, 2019
/s/ O. ANDREAS HALVORSEN
By: O. Andreas Halvorsen - individually
and as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive
Committee Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING
GLOBAL OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/ DAVID C. OTT
By: David C. Ott - individually and as
an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee
Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL
OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/ ROSE S. SHABET
By: Rose S. Shabet - individually and
as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee
Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL
OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
EXHIBIT A - JOINT FILING AGREEMENT
This joint filing agreement is made and entered
into as of this 10
th
day of January, 2019, by and among Viking Global Investors LP, Viking Global Opportunities GP LLC,
Viking Global Opportunities Portfolio GP LLC, Viking Global Opportunities Liquid Portfolio Sub-Master LP, Viking Global Opportunities
Illiquid Investments Sub-Master LP, O. Andreas Halvorsen, David C. Ott and Rose S. Shabet.
The parties hereby agree to jointly prepare
and file a Schedule 13G with respect to Eidos Therapeutics, Inc., as well as any amendments thereto, pursuant to the Securities
Exchange Act of 1934, as amended.
IN WITNESS WHEREOF, the parties hereto have
executed this agreement as of the date first set forth above.
Dated: January 10, 2019
/s/ O. ANDREAS HALVORSEN
By: O. Andreas Halvorsen - individually
and as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive
Committee Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING
GLOBAL OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/ DAVID C. OTT
By: David C. Ott - individually and as
an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee
Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL
OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP
/s/ ROSE S. SHABET
By: Rose S. Shabet - individually and
as an Executive Committee Member of VIKING GLOBAL PARTNERS LLC, on behalf of VIKING GLOBAL INVESTORS LP, and as an Executive Committee
Member of VIKING GLOBAL OPPORTUNITIES GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL
OPPORTUNITIES LIQUID PORTFOLIO SUB-MASTER LP, and VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP