Director at Dianthus Therapeutics (DNTH) exercises options and sells shares

Rhea-AI Filing Summary

Dianthus Therapeutics director Paula Soteropoulos exercised stock options for 27,594 shares of common stock at an exercise price of $8.44 per share and immediately sold the same 27,594 shares in an open-market transaction at $78.05 per share. These transactions were carried out under a pre-arranged Rule 10b5-1 trading plan adopted on December 23, 2025. Following the sale, she held no shares of common stock directly.

Insider Trade Summary 10b5-1

Net Seller: 27,594 shares ($2,153,712)

Net Sell 3 txns

Insider Soteropoulos Paula

Role Director

Sold 27,594 shs ($2.15M)

Type	Security	Shares	Price	Value
Exercise	Stock Option (Right to Buy)	27,594	$0.00	--
Exercise	Common Stock	27,594	$8.44	$233K
Sale	Common Stock	27,594	$78.05	$2.15M

Holdings After Transaction: Stock Option (Right to Buy) — 1,198 shares (Direct); Common Stock — 27,594 shares (Direct)

Footnotes (1)

1. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 23, 2025. The shares of common stock underlying this stock option award vested as to 25% of the shares on April 6, 2023, with the remaining three quarters vesting in equal monthly installments over the following three years, subject to the Reporting Person's continued service to the Issuer on each such vesting date.

Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Soteropoulos Paula

(Last) (First) (Middle)

C/O DIANTHUS THERAPEUTICS, INC.

7 TIMES SQUARE, 43RD FLOOR

(Street)

NEW YORK NEW YORK 10036

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Dianthus Therapeutics, Inc. /DE/ [ DNTH ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
03/24/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/24/2026		M(1)		27,594	A	$8.44	27,594	D
Common Stock	03/24/2026		S(1)		27,594	D	$78.05	0	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Stock Option (Right to Buy)	$8.44	03/24/2026		M(1)			27,594	(2)	06/06/2032	Common Stock	27,594	$0	1,198	D

Explanation of Responses:

1. The reported transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on December 23, 2025.

2. The shares of common stock underlying this stock option award vested as to 25% of the shares on April 6, 2023, with the remaining three quarters vesting in equal monthly installments over the following three years, subject to the Reporting Person's continued service to the Issuer on each such vesting date.

	/s/ Adam Veness, as attorney-in-fact for Paula Soteropoulos	03/26/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)

FAQ

What insider transaction did Dianthus Therapeutics (DNTH) disclose?

Dianthus Therapeutics reported that director Paula Soteropoulos exercised options for 27,594 shares at $8.44 and sold all 27,594 shares at $78.05. The filing describes these as open-market sales following a derivative option exercise.

How many Dianthus Therapeutics (DNTH) shares did the director sell?

The director sold 27,594 shares of Dianthus Therapeutics common stock. These shares were first acquired through exercising stock options and then fully sold in an open-market transaction on the same date, according to the Form 4 disclosure.

At what prices did the Dianthus Therapeutics (DNTH) option exercise and sale occur?

The stock options were exercised at an exercise price of $8.44 per share. The resulting 27,594 common shares were then sold at a reported transaction price of $78.05 per share in an open-market sale on the same day.

Was the Dianthus Therapeutics (DNTH) insider trade under a Rule 10b5-1 plan?

Yes. The filing states the reported transaction was effected under a Rule 10b5-1 trading plan adopted by the reporting person on December 23, 2025. Such plans pre-schedule trades, making the timing more routine and less discretionary.

What are Paula Soteropoulos’s holdings in Dianthus Therapeutics (DNTH) after these trades?

After selling the 27,594 shares of common stock, the Form 4 shows zero shares of Dianthus Therapeutics common stock held directly. The reported post-transaction balance for the sold common stock position is 0.0000 shares.

What type of security did the Dianthus Therapeutics (DNTH) director exercise?

The director exercised a stock option (right to buy) covering 27,594 underlying shares of Dianthus common stock. The option carried an exercise price of $8.44 and had an original expiration date in 2032, as described in the Form 4.