Cash merger pays Astria Therapeutics (ATXS) investors $8.55 per share as Magnetar exits

Rhea-AI Filing Summary

Astria Therapeutics, Inc. completed a cash merger in which each share of its Class A common stock was converted into the right to receive $8.55 in cash, without interest, as of the closing on January 23, 2026.

Funds and accounts managed by Magnetar-affiliated entities previously held 3,431,007 shares, which were cancelled and converted into this cash consideration. The filing states that, following the merger, Magnetar Financial LLC, Magnetar Capital Partners, Supernova Management LLC, and David J. Snyderman each report beneficial ownership of 0 shares, or 0% of the class.

The amendment also notes that since their October 24, 2025 report, the reporting persons purchased an additional 118,805 shares for an aggregate of $1,501,294.83 on behalf of the funds before all holdings were cashed out in the merger.

Insights

Equity analyst

Filing confirms Astria’s cash merger at $8.55 per share and Magnetar’s complete exit.

This amendment shows that Astria’s Class A common stock was cashed out at $8.55 per share when the merger closed on January 23, 2026. Magnetar-managed funds had accumulated 118,805 additional shares since October 24, 2025, bringing total reported holdings to 3,431,007 shares before the transaction.

All of those 3,431,007 shares were cancelled and converted into the cash consideration, leaving Magnetar Financial LLC, Magnetar Capital Partners, Supernova Management LLC, and David J. Snyderman with beneficial ownership of 0 shares, or 0% of the class. This filing mainly documents a completed change-of-control outcome for prior shareholders.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

Astria Therapeutics, Inc.

(Name of Issuer)

Class A Common Stock, par value $0.001

(Title of Class of Securities)

04635X102

(CUSIP Number)

David J. Snyderman
1603 Orrington Avenue, 13th Floor
Evanston, IL, 60201
847-905-4400

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

01/26/2026

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on 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).

SCHEDULE 13D

CUSIP No. 04635X102

1

Name of reporting person

Magnetar Financial LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0 %

14

Type of Reporting Person (See Instructions)

IA, OO

SCHEDULE 13D

CUSIP No. 04635X102

1

Name of reporting person

Magnetar Capital Partners LP

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0 %

14

Type of Reporting Person (See Instructions)

HC, OO

SCHEDULE 13D

CUSIP No. 04635X102

1

Name of reporting person

Supernova Management LLC

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0 %

14

Type of Reporting Person (See Instructions)

HC, OO

SCHEDULE 13D

CUSIP No. 04635X102

1

Name of reporting person

David J. Snyderman

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

OO

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

0.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

0 %

14

Type of Reporting Person (See Instructions)

IN, HC

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Class A Common Stock, par value $0.001
(b)	Name of Issuer: Astria Therapeutics, Inc.
(c)	Address of Issuer's Principal Executive Offices: 22 BOSTON WHARF ROAD, 10TH FLOOR, BOSTON, MASSACHUSETTS , 02210.
Item 3.	Source and Amount of Funds or Other Consideration
	Since the filing of the Reporting Persons' Form 13D Report of the Issuer on October 24, 2025, the Reporting Persons have purchased 118,805 Shares on behalf of the Funds. The aggregate amount of funds used by the Reporting Persons in purchasing the 118,805 Shares reported herein on behalf of the Funds have come directly from the assets of the Funds, which may any given time, have included margin loans made by brokerage firms in the ordinary course of business. The aggregate amount of funds used by the Reporting Persons was $1,501,294.83 (excluding commissions and other execution-related costs).
Item 4.	Purpose of Transaction
	Since the filing of the Schedule 13D on October 24, 2025, on January 23, 2026, the Issuer consummated a merger (the "Merger") pursuant to which each issued and outstanding Share was cancelled and converted into the right to receive $8.55 in cash, without interest. In connection with the Merger, the Reporting Persons' 3,431,007 Shares, which consisted of 1,560,502 Shares sold for the benefit of PRA Master Fund; 804,159 Shares sold for the benefit of Systematic Master Fund; 221,576 Shares sold for the benefit of the Relative Value Master Fund and 844,770 Shares sold for the benefit of two Managed Accounts, were cancelled and converted into the right to receive $8.55 in cash, without interest.
Item 5.	Interest in Securities of the Issuer
(a)	As of the closing of the Merger on January 23, 2026, each of the Reporting Persons may have been deemed to have beneficial ownership of 0 Shares.
(b)	As of the closing of the Merger on January 23, 2026, each of the Reporting Persons may have been deemed to share the power to vote and direct the disposition of 0 Shares, which represented beneficial ownership of 0% of the Shares.
(c)	Except as set forth on Schedule A attached hereto and Item 6, the Funds had no transactions in the Shares during the 60 days preceding the date of filing of this Statement. All of the transactions set forth on Schedule A attached hereto were effected in the ordinary course of business of Magnetar Financial for the accounts of each of the Funds. The transactions in the Shares set forth on Schedule A were effected in open market transactions on the NASDAQ and various other trading markets.
(e)	01-26-2026
Item 7.	Material to be Filed as Exhibits.
	99.1 Joint Filing Agreement, dated as of January 28, 2026, among the Reporting Persons. 99.2 Power of Attorney, dated as of December 22, 2022 filed by the Reporting Persons on January 28, 2026. 99.3 Schedule A, dated as of January 28, 2026.

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.

Magnetar Financial LLC

Signature:	/s/ Hayley Stein
Name/Title:	Hayley Stein, Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Mgmt LLC, GP of Magnetar Capital Partners LP, its Sol Mem
Date:	01/28/2026

Magnetar Capital Partners LP

Signature:	/s/ Hayley Stein
Name/Title:	Hayley Stein, Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Management LLC, its General Partner
Date:	01/28/2026

Supernova Management LLC

Signature:	/s/ Hayley Stein
Name/Title:	Hayley Stein, Attorney-in-fact for David J. Snyderman, Administrative Manager of Supernova Management LLC
Date:	01/28/2026

David J. Snyderman

Signature:	/s/ Hayley Stein
Name/Title:	Hayley Stein, Attorney-in-fact for David J. Snyderman
Date:	01/28/2026

Comments accompanying signature:

MAGNETAR FINANCIAL LLC BY: Magnetar Capital Partners LP, its Sole Member BY: Supernova Management LLC, its General Partner MAGNETAR CAPITAL PARTNERS LP By: Supernova Management LLC, its General Partner

FAQ

What does Astria Therapeutics (ATXS) latest Schedule 13D/A report show?

The amendment reports completion of a cash merger where each Astria Therapeutics share was converted into the right to receive $8.55 in cash. It also shows Magnetar-affiliated entities now report 0 shares and 0% beneficial ownership following the merger’s closing on January 23, 2026.

At what price were Astria Therapeutics (ATXS) shares cashed out in the merger?

Each Astria Therapeutics Class A common share was cancelled and converted into the right to receive $8.55 in cash, without interest. This per-share cash amount applied to all issued and outstanding shares as of the merger closing on January 23, 2026, according to the filing.

How many Astria Therapeutics shares did Magnetar-related funds hold before the merger?

Magnetar-related funds and managed accounts held a total of 3,431,007 Astria shares before the merger closed. These included shares held for PRA Master Fund, Systematic Master Fund, Relative Value Master Fund, and two managed accounts, all of which were converted into $8.55 per share cash consideration.

Does Magnetar still own any Astria Therapeutics (ATXS) stock after the merger?

No. The amendment states that after the merger closed, each reporting person was deemed to beneficially own 0 shares, representing 0% of Astria’s Class A common stock. Their prior 3,431,007 shares were cancelled and converted into the $8.55 per share cash payment.

How much capital did Magnetar deploy buying Astria Therapeutics shares before the merger?

Since their October 24, 2025 report, the reporting persons purchased an additional 118,805 Astria shares on behalf of their funds. The filing states the aggregate funds used for these purchases were $1,501,294.83, excluding commissions and other execution-related costs associated with those transactions.

Which Magnetar-affiliated entities are named in the Astria Therapeutics Schedule 13D/A?

The amendment lists Magnetar Financial LLC, Magnetar Capital Partners, Supernova Management LLC, and David J. Snyderman as reporting persons. Each is shown with 0 shares of Astria Therapeutics beneficially owned and 0% of the class after the January 23, 2026 merger closing.