DIANTHUS THERAPEUTICS

2026 ANNUAL MEETING

INVESTOR MATERIALS

ANNUAL REPORT

View our annual report summarizing our financial and operational performance for the past year.

PROXY STATEMENT

View our proxy statement outlining key information about the upcoming shareholder meeting.

REQUEST PAPER MATERIALS

Request paper copies of the above proxy materials online now, via email or via phone
by dialing 866-648-8133.

Materials
Voting

VOTING

Your vote is important! Please be sure to vote your shares online now or via phone by dialing 866-230-6343.

Annual Meeting Details

Date

Thursday, May 21, 2026

Virtual Meeting

Note: You must register to be eligible to participate in the meeting.

Time

9:00 a.m. Eastern Time

ABOUT US

We are developing potentially best in class therapies for patients living with severe autoimmune diseases. Our lead antibody, claseprubart (DNTH103), is purposefully engineered with extended half-life, improved potency, and high selectivity for only the active C1s complement protein that drives disease pathology – enabling less frequent and more convenient self-administered subcutaneous injections. Our second clinical candidate, DNTH212 is a first and potentially best in class, bifunctional inhibitor that targets clinically validated and complementary disease modifying mechanisms, Type 1 IFN suppression and B cell modulation – enabling potential for improved clinical outcomes and patient friendly convenient, self-administered subcutaneous injections.