[SCHEDULE 13G/A] Trevi Therapeutics, Inc. SEC Filing

Rhea-AI Filing Summary

Viking Global Investors and affiliated entities report beneficial ownership of 7,505,694 shares of Trevi Therapeutics (TRVI), representing 5.9% of the common stock. The holdings consist of 1,543,000 shares directly owned by two affiliated entities (1,033,810 by VGOP and 509,190 by VGOD) and 5,962,694 shares issuable upon exercise of pre-funded warrants exercisable at $0.001 per share. The filing clarifies the ownership chain through multiple Delaware and Cayman entities and notes shared voting and dispositive power among the reporting persons, including O. Andreas Halvorsen, David C. Ott and Rose S. Shabet. The statement affirms these securities were not acquired to change or influence control of the issuer.

Positive

• Material passive stake disclosed: Viking Global Investors and affiliates beneficially own 7,505,694 shares (5.9%) of TRVI.
• Warrant transparency: Filing specifies 5,962,694 shares are exercisable upon exercise of pre-funded warrants at $0.001 per share.
• Clear ownership chain: The statement details the fund structure and identifies persons with shared voting and dispositive authority, including Halvorsen, Ott and Shabet.
• Filed as passive (Schedule 13G/A): Reporting persons certify the position is not for changing or influencing control of the issuer.

Negative

• None.

Insights

Financial Analyst

TL;DR: Viking Global-affiliated funds hold 5.9% of TRVI, combining direct shares and warrant exposure, a material passive stake.

The Schedule 13G/A discloses a 5.9% economic and voting interest in Trevi Therapeutics via direct holdings and exercisable pre-funded warrants. For investors, the key fact is the combined exposure of 7,505,694 shares, of which 5,962,694 are currently exercisable warrants, which could increase voting shares if exercised. The filing is presented under passive-investor rules and expressly states the position is not intended to influence control. This is a material disclosure by size but framed as non-activist by the reporting persons.

Corporate Governance Expert

TL;DR: Multiple affiliated entities and named executives share voting/dispositive power over a 5.9% stake, disclosed under Schedule 13G/A.

The document maps the control chain: VGI provides managerial services and may be deemed the beneficial owner under Rule 13d-3, while Opportunities Parent and several GP/LP entities hold and control the underlying economic interests. Executive Committee members Halvorsen, Ott and Shabet are identified as having shared authority, but the certification confirms no intent to change control. From a governance perspective, this is a routine but material ownership disclosure highlighting the practical delegation of voting and disposition across fund structures.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

Trevi Therapeutics, Inc.

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

89532M101

(CUSIP Number)

06/30/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

VIKING GLOBAL INVESTORS LP

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 7,505,694.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 7,505,694.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

7,505,694.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.9 %

12

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Parent GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 7,505,694.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 7,505,694.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

7,505,694.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.9 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 5,028,815.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,028,815.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,028,815.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

3.9 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Portfolio GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 5,028,815.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,028,815.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,028,815.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

3.9 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Illiquid Investments Sub-Master LP

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 5,028,815.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 5,028,815.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,028,815.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

3.9 %

12

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Drawdown GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 2,476,879.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,476,879.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,476,879.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

1.9 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Drawdown Portfolio GP LLC

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 2,476,879.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,476,879.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,476,879.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

1.9 %

12

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Viking Global Opportunities Drawdown (Aggregator) LP

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 2,476,879.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 2,476,879.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,476,879.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

1.9 %

12

Type of Reporting Person (See Instructions)

PN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

HALVORSEN OLE ANDREAS

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 7,505,694.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 7,505,694.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

7,505,694.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.9 %

12

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Ott David C.

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 7,505,694.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 7,505,694.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

7,505,694.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.9 %

12

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

CUSIP No. 89532M101

1

Names of Reporting Persons

Shabet Rose Sharon

2

Check the appropriate box if a member of a Group (see instructions)

(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 0.00
6	Shared Voting Power 7,505,694.00
7	Sole Dispositive Power 0.00
8	Shared Dispositive Power 7,505,694.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

7,505,694.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

5.9 %

12

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person: See Item 4

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Trevi Therapeutics, Inc.
(b)	Address of issuer's principal executive offices: 195 Church Street, 16th Floor, New Haven, Connecticut, 06510
Item 2.
(a)	Name of person filing: Viking Global Investors LP ("VGI"), Viking Global Opportunities Parent GP LLC ("Opportunities Parent"), Viking Global Opportunities GP LLC ("Opportunities GP"), Viking Global Opportunities Portfolio GP LLC ("Opportunities Portfolio GP"), Viking Global Opportunities Illiquid Investments Sub-Master LP ("VGOP"), Viking Global Opportunities Drawdown GP LLC ("VGOD GP"), Viking Global Opportunities Drawdown Portfolio GP LLC ("VGOD Portfolio GP"), Viking Global Opportunities Drawdown (Aggregator) LP ("VGOD"), O. Andreas Halvorsen, David C. Ott and Rose S. Shabet (collectively, the "Reporting Persons")
(b)	Address or principal business office or, if none, residence: The business address of each of the Reporting Persons is: 600 Washington Boulevard, Floor 11, Stamford, Connecticut 06901.
(c)	Citizenship: VGI is a Delaware limited partnership; Opportunities Parent, Opportunities GP, Opportunities Portfolio GP, VGOD GP and VGOD Portfolio GP are Delaware limited liability companies; VGOP and VGOD 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.
(d)	Title of class of securities: Common Stock, $0.001 par value per share
(e)	CUSIP No.: 89532M101
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 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)	Amount beneficially owned: This Statement on Schedule 13G relates to shares of Common Stock and pre-funded warrants to purchase shares of Common Stock with an exercise price of $0.001 per share (the "Warrants") held directly by VGOP and VGOD. VGI: 7,505,694 VGI provides managerial services to VGOP and VGOD. VGI has the authority to dispose of and vote the shares of Common Stock that VGOP and VGOD directly own or have the right to purchase upon exercise of the Warrants. VGI does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Securities Exchange Act of 1934, as amended (the "Act"), VGI may be deemed to beneficially own the shares of Common Stock that VGOP and VGOD directly own or have the right to purchase upon exercise of the Warrants. VGI beneficially owns 7,505,694 shares of Common Stock consisting of (i) 1,033,810 and 509,190 shares of Common Stock directly owned by VGOP and VGOD, respectively, and (ii) 3,995,005 and 1,967,689 shares of Common Stock beneficially owned by VGOP and VGOD, respectively, which VGOP and VGOD have the right to purchase upon exercise of the Warrants. Opportunities Parent: 7,505,694 Opportunities Parent is the sole member of Opportunities GP, which 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 that VGOP directly owns or has the right to purchase upon exercise of the Warrants), and is the sole member of VGOD GP, which has the authority to dispose of and vote the shares of Common Stock controlled by VGOD Portfolio GP (which consists of the shares of Common Stock that VGOD directly owns or has the right to purchase upon exercise of the Warrants). Opportunities Parent does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, Opportunities Parent may be deemed to beneficially own the shares of Common Stock that VGOP and VGOD directly own or have the right to purchase upon exercise of the Warrants. Opportunities Parent beneficially owns 7,505,694 shares of Common Stock consisting of (i) 1,033,810 and 509,190 shares of Common Stock directly owned by VGOP and VGOD, respectively, and (ii) 3,995,005 and 1,967,689 shares of Common Stock beneficially owned by VGOP and VGOD, respectively, which VGOP and VGOD have the right to purchase upon exercise of the Warrants. Opportunities GP: 5,028,815 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 that VGOP directly owns or has the right to purchase upon exercise of the Warrants. In addition, Opportunities GP is the general partner of each of Viking Global Opportunities Intermediate LP, Viking Global Opportunities III LP, and Viking Global Opportunities LP. Opportunities GP does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, Opportunities GP may be deemed to beneficially own the shares of Common Stock that VGOP directly owns or has the right to purchase upon exercise of the Warrants. Opportunities GP beneficially owns 5,028,815 shares of Common Stock consisting of 1,033,810 shares of Common Stock directly owned by VGOP and 3,995,005 shares of Common Stock beneficially owned by VGOP, which VGOP has the right to purchase upon exercise of the Warrants. Opportunities Portfolio GP: 5,028,815 Opportunities Portfolio GP serves as the general partner of VGOP and has the authority to dispose of and vote the shares of Common Stock that VGOP directly owns or has the right to purchase upon exercise of the Warrants. Opportunities Portfolio GP does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, Opportunities Portfolio GP may be deemed to beneficially own the shares of Common Stock that VGOP directly owns or has the right to purchase upon exercise of the Warrants. Opportunities Portfolio GP beneficially owns 5,028,815 shares of Common Stock consisting of 1,033,810 shares of Common Stock directly owned by VGOP and 3,995,005 shares of Common Stock beneficially owned by VGOP, which VGOP has the right to purchase upon exercise of the Warrants. VGOP: 5,028,815 VGOP has the authority to dispose of and vote the 1,033,810 shares of Common Stock that it owns and the 3,995,005 shares of Common Stock it has the right to purchase upon exercise of the Warrants 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. VGOD GP: 2,476,879 VGOD GP serves as the sole member of VGOD Portfolio GP and has the authority to dispose of and vote the shares of Common Stock controlled by VGOD Portfolio GP, which consists of the shares of Common Stock that VGOD directly owns or has the right to purchase upon exercise of the Warrants. In addition, VGOD GP is the general partner of each of Viking Global Opportunities Drawdown (Internal) LP, Viking Global Opportunities Drawdown (Onshore) LP, and Viking Global Opportunities Drawdown (Offshore) LP. VGOD GP does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, VGOD GP may be deemed to beneficially own the shares of Common Stock that VGOD directly owns or has the right to purchase upon exercise of the Warrants. VGOD GP beneficially owns 2,476,879 shares of Common Stock consisting of 509,190 shares of Common Stock directly owned by VGOD and 1,967,689 shares of Common Stock beneficially owned by VGOD, which VGOD has the right to purchase upon exercise of the Warrants. VGOD Portfolio GP: 2,476,879 VGOD Portfolio GP serves as the general partner of VGOD and has the authority to dispose of and vote the shares of Common Stock that VGOD directly owns or has the right to purchase upon exercise of the Warrants. VGOD Portfolio GP does not directly own any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, VGOD Portfolio GP may be deemed to beneficially own the shares of Common Stock that VGOD directly owns or has the right to purchase upon exercise of the Warrants. VGOD Portfolio GP beneficially owns 2,476,879 shares of Common Stock consisting of 509,190 shares of Common Stock directly owned by VGOD and 1,967,689 shares of Common Stock beneficially owned by VGOD, which VGOD has the right to purchase upon exercise of the Warrants. VGOD: 2,476,879 VGOD has the authority to dispose of and vote the 509,190 shares of Common Stock that it directly owns and the 1,967,689 shares of Common Stock it has the right to purchase upon exercise of the Warrants directly owned by it, which power may be exercised by VGOD Portfolio GP, and by VGI, an affiliate of VGOD Portfolio GP, which provides managerial services to VGOD. Viking Global Opportunities Drawdown (Offshore) LP (a Cayman Islands exempted limited partnership) and Viking Global Opportunities Drawdown (Internal) LP (a Delaware limited partnership), through its investment in Viking Global Opportunities Drawdown (Onshore) LP (a Delaware limited partnership), invest substantially all of their assets in VGOD. O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 7,505,694 Mr. Halvorsen, Mr. Ott and Ms. Shabet, as Executive Committee Members of Viking Global Partners LLC (general partner of VGI) and Opportunities Parent, have shared authority to dispose of and vote the shares of Common Stock beneficially owned by VGI and Opportunities Parent. None of Mr. Halvorsen, Mr. Ott and Ms. Shabet directly owns any shares of Common Stock or Warrants. Based on Rule 13d-3 under the Act, each may be deemed to beneficially own the shares of Common Stock that VGOP and VGOD directly own or have the right to purchase upon exercise of the Warrants. Each of Mr. Halvorsen, Mr. Ott and Ms. Shabet beneficially owns 7,505,694 shares of Common Stock consisting of (i) 1,033,810 and 509,190 shares of Common Stock directly owned by VGOP and VGOD, respectively, and (ii) 3,995,005 and 1,967,689 shares of Common Stock beneficially owned by VGOP and VGOD, respectively, which VGOP and VGOD have the right to purchase upon exercise of the Warrants.
(b)	Percent of class: The percentages set forth herein are based on (i) 121,775,753 shares of Common Stock outstanding as of June 30, 2025, as reported in the Issuer's quarterly report on Form 10-Q, filed with the Securities and Exchange Commission (the "Commission") on August 7, 2025, and (ii) 5,962,694 shares of Common Stock that the Reporting Persons currently have the right to purchase upon exercise of the Warrants. VGI: 5.9% Opportunities Parent: 5.9% Opportunities GP: 3.9% Opportunities Portfolio GP: 3.9% VGOP: 3.9% VGOD GP: 1.9% VGOD Portfolio GP: 1.9% VGOD: 1.9% O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 5.9%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: VGI: 0 Opportunities Parent: 0 Opportunities GP: 0 Opportunities Portfolio GP: 0 VGOP: 0 VGOD GP: 0 VGOD Portfolio GP: 0 VGOD: 0 O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 0
	(ii) Shared power to vote or to direct the vote: VGI: 7,505,694 Opportunities Parent: 7,505,694 Opportunities GP: 5,028,815 Opportunities Portfolio GP: 5,028,815 VGOP: 5,028,815 VGOD GP: 2,476,879 VGOD Portfolio GP: 2,476,879 VGOD: 2,476,879 O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 7,505,694
	(iii) Sole power to dispose or to direct the disposition of: VGI: 0 Opportunities Parent: 0 Opportunities GP: 0 Opportunities Portfolio GP: 0 VGOP: 0 VGOD GP: 0 VGOD Portfolio GP: 0 VGOD: 0 O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 0
	(iv) Shared power to dispose or to direct the disposition of: VGI: 7,505,694 Opportunities Parent: 7,505,694 Opportunities GP: 5,028,815 Opportunities Portfolio GP: 5,028,815 VGOP: 5,028,815 VGOD GP: 2,476,879 VGOD Portfolio GP: 2,476,879 VGOD: 2,476,879 O. Andreas Halvorsen, David C. Ott and Rose S. Shabet: 7,505,694
Item 5.	Ownership of 5 Percent or Less of a Class.
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	If any other person is known to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, such securities, a statement to that effect should be included in response to this item and, if such interest relates to more than 5 percent of the class, such person should be identified. A listing of the shareholders of an investment company registered under the Investment Company Act of 1940 or the beneficiaries of employee benefit plan, pension fund or endowment fund is not required. The response to Item 4 is incorporated by reference herein.
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	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.

Certifications:

By signing below I certify that, to the best of my 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, other than activities solely in connection with a nomination under ?? 240.14a-11.

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.

VIKING GLOBAL INVESTORS LP

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of VIKING GLOBAL INVESTORS LP (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Parent GP LLC

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Parent GP LLC (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities GP LLC

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities GP LLC (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Portfolio GP LLC

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Portfolio GP LLC (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Illiquid Investments Sub-Master LP

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Illiquid Investments Sub-Master LP (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Drawdown GP LLC

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Drawdown GP LLC (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Drawdown Portfolio GP LLC

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Drawdown Portfolio GP LLC (1)(2)(3)
Date:	08/14/2025

Viking Global Opportunities Drawdown (Aggregator) LP

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Viking Global Opportunities Drawdown (Aggregator) LP (1)(2)(3)
Date:	08/14/2025

HALVORSEN OLE ANDREAS

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of O. Andreas Halvorsen (1)
Date:	08/14/2025

Ott David C.

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of David C. Ott (2)
Date:	08/14/2025

Shabet Rose Sharon

Signature:	/s/ Scott M. Hendler
Name/Title:	Scott M. Hendler on behalf of Rose S. Shabet (3)
Date:	08/14/2025

Comments accompanying signature: (1) Scott M. Hendler is signing on behalf of 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 PARENT GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES GP LLC, VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP, VIKING GLOBAL OPPORTUNITIES DRAWDOWN GP LLC, VIKING GLOBAL OPPORTUNITIES DRAWDOWN PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES DRAWDOWN (AGGREGATOR) LP, pursuant to an authorization and designation letter dated February 9, 2021, which was previously filed with the Commission as an exhibit to a Form 13G filed by Mr. Halvorsen on February 12, 2021 (SEC File No. 005-49737). (2) Scott M. Hendler is signing on behalf of 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 PARENT GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES GP LLC, VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP, VIKING GLOBAL OPPORTUNITIES DRAWDOWN GP LLC, VIKING GLOBAL OPPORTUNITIES DRAWDOWN PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES DRAWDOWN (AGGREGATOR) LP, pursuant to an authorization and designation letter dated February 9, 2021, which was previously filed with the Commission as an exhibit to a Form 13G filed by Mr. Halvorsen on February 12, 2021 (SEC File No. 005-49737). (3) Scott M. Hendler is signing on behalf of 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 PARENT GP LLC, on behalf of itself and VIKING GLOBAL OPPORTUNITIES GP LLC, VIKING GLOBAL OPPORTUNITIES PORTFOLIO GP LLC, VIKING GLOBAL OPPORTUNITIES ILLIQUID INVESTMENTS SUB-MASTER LP, VIKING GLOBAL OPPORTUNITIES DRAWDOWN GP LLC, VIKING GLOBAL OPPORTUNITIES DRAWDOWN PORTFOLIO GP LLC and VIKING GLOBAL OPPORTUNITIES DRAWDOWN (AGGREGATOR) LP, pursuant to an authorization and designation letter dated February 9, 2021, which was previously filed with the Commission as an exhibit to a Form 13G filed by Mr. Halvorsen on February 12, 2021 (SEC File No. 005-49737).

Exhibit Information

EXHIBIT A - JOINT FILING AGREEMENT

FAQ

How many Trevi Therapeutics (TRVI) shares does Viking Global beneficially own?

The reporting persons beneficially own 7,505,694 shares of Trevi Therapeutics common stock, representing 5.9% of the class.

How much of the Viking Global position in TRVI is from exercisable warrants?

The filing states 5,962,694 shares are issuable upon exercise of pre-funded warrants exercisable at $0.001 per share.

Do the reporting persons intend to influence control of Trevi Therapeutics?

No. The filing includes a certification that the securities were not acquired and are not held to change or influence control of the issuer.

Which individuals are identified as having shared voting authority over the TRVI stake?

O. Andreas Halvorsen, David C. Ott and Rose S. Shabet are named as Executive Committee members with shared authority to vote and dispose of the shares.

What is the total share count used to calculate the 5.9% ownership percentage?

The percentage is based on 121,775,753 shares outstanding as of June 30, 2025, plus the 5,962,694 shares issuable upon exercise of the warrants.