UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _________________ to _________________ Commission File Number: 001-38541 Dianthus Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) ...

[Filing Information](index=1&type=section&id=Filing%20Information) This section details the registrant's identification, contact information, registered securities, and emerging growth company status [Registrant Details](index=1&type=section&id=Registrant%20Details) This section provides the core identification details for Dianthus Therapeutics, Inc., including its legal name, jurisdiction of incorporation, principal executive offices, and contact information - The exact name of the Registrant is **DIANTHUS THERAPEUTICS, INC.**[2](index=2&type=chunk) - The Registrant's jurisdiction of incorporation is Delaware[2](index=2&type=chunk) - The address of Principal Executive Offices is 7 Times Square, 43rd Floor, New York, New York 10036, with telephone number (929) 999-4055[2](index=2&type=chunk) [Securities and Status](index=1&type=section&id=Securities%20and%20Status) This part outlines the company's registered securities and its status regarding emerging growth company provisions Registered Securities | Title of each class | Symbol(s) | Name of each exchange on which registered | | :------------------ | :-------- | :---------------------------------------- | | Common Stock, $0.001 Par Value | DNTH | The Nasdaq Capital Market | - The registrant indicated it is not an emerging growth company[4](index=4&type=chunk) [Item 1.01 Entry into a Material Definitive Agreement](index=3&type=section&id=Item%201.01%20Entry%20into%20a%20Material%20Definitive%20Agreement) Dianthus Therapeutics, Inc. entered into a significant exclusive license and collaboration agreement with Nanjing Leads Biolabs Co. Ltd. for DNTH212 [License Agreement with Nanjing Leads Biolabs Co. Ltd.](index=3&type=section&id=License%20Agreement%20with%20Nanjing%20Leads%20Biolabs%20Co.%20Ltd.) Dianthus Therapeutics, Inc. entered into an exclusive, royalty-bearing License and Collaboration Agreement with Nanjing Leads Biolabs Co. Ltd. for the development and commercialization of DNTH212 (LBL-047) globally outside of Greater China [Agreement Overview](index=3&type=section&id=Agreement%20Overview) Dianthus secured an exclusive, royalty-bearing license for DNTH212 (LBL-047) from Leads Biolabs, covering development, manufacturing, and commercialization outside Greater China. DNTH212 is an investigational bifunctional fusion protein targeting BDCA2 and inhibiting BAFF/APRIL - On October 16, 2025, Dianthus Therapeutics, Inc. entered into a License and Collaboration Agreement with Nanjing Leads Biolabs Co. Ltd.[6](index=6&type=chunk) - Dianthus obtained a royalty-bearing, exclusive license outside of Greater China to develop, manufacture, commercialize, or otherwise exploit LBL-047, referred to as DNTH212[6](index=6&type=chunk) - DNTH212 is an investigational, extended half-life bifunctional fusion protein targeting plasmacytoid dendritic cell (pDC) BDCA2 to reduce Type 1 interferon production, while simultaneously inhibiting BAFF/APRIL to suppress B cell function[6](index=6&type=chunk) [Financial Terms (Consideration)](index=3&type=section&id=Financial%20Terms%20(Consideration)) Dianthus will make upfront and near-term milestone payments of up to $38 million to Leads, with potential additional payments of up to $962 million for development, regulatory approval, and sales-based milestones across five indications, plus tiered royalties on net sales outside Greater China License Agreement Financial Terms | Payment Type | Amount | | :----------- | :----- | | Upfront and Near-term Milestone Payments | Up to **$38 million** (comprised of $30 million upfront/near-term + $8 million upon Phase 1 study initiation) | | Development and Regulatory Approval Milestones | Up to **$962 million** (across five indications) | | Sales-based Milestones | Included in the $962 million total | | Tiered Royalties | Mid-single digits up to a low double-digit on ex-Greater China net sales | [Governance and Development](index=3&type=section&id=Governance%20and%20Development) A joint steering committee will oversee DNTH212 activities. Leads retains the right to participate in Dianthus's global clinical studies and enroll patients in Greater China, bearing associated costs for those patients - A joint steering committee will oversee manufacturing, development, and commercial activities related to DNTH212[8](index=8&type=chunk) - Leads will have the right to participate in Dianthus's global clinical studies with DNTH212 and enroll patients in Greater China, being responsible for certain costs for those patients[8](index=8&type=chunk) [Non-Competition Clause](index=3&type=section&id=Non-Competition%20Clause) Both Dianthus and Leads are contractually prohibited from engaging in research, development, manufacturing, or commercialization of competing products within Dianthus's licensed territory outside of Greater China - Leads and Dianthus are prohibited from directly or indirectly researching, developing, manufacturing, or commercializing a competing product in Dianthus's territory outside of Greater China[9](index=9&type=chunk) [Term and Termination](index=3&type=section&id=Term%20and%20Termination) The License Agreement remains effective on a country-by-country and product-by-product basis until the expiration of the applicable royalty term, unless terminated earlier. Both parties have customary termination rights, including for material breach, insolvency, patent challenge, or, for Dianthus, for convenience - The License Agreement will remain in effect on a country-by-country and product-by-product basis until the expiration of the applicable royalty term, unless earlier terminated[10](index=10&type=chunk) - Each party has customary termination rights, including for uncured material breach, insolvency, patent challenge, or, in the case of Dianthus, for convenience[10](index=10&type=chunk) [Item 2.02 Results of Operations and Financial Condition](index=3&type=section&id=Item%202.02%20Results%20of%20Operations%20and%20Financial%20Condition) This item incorporates by reference the preliminary financial information for the three months ended September 30, 2025, as disclosed under Item 8.01. It clarifies that such information is 'furnished' rather than 'filed,' limiting its liability and restrictions on incorporation by reference - Preliminary financial information for the three months ended September 30, 2025, set forth under 'Preliminary Financial Information for the Three Months Ended September 30, 2025' in Item 8.01, is incorporated by reference[12](index=12&type=chunk) - This information is 'furnished' and not 'filed,' meaning it is not subject to the liability provisions of Section 18 of the Exchange Act or Sections 11 and 12(a)(2) of the Securities Act, and generally cannot be incorporated by reference into other filings[13](index=13&type=chunk) [Item 8.01 Regulation FD Disclosure and Preliminary Financial Information](index=3&type=section&id=Item%208.01%20Regulation%20FD%20Disclosure%20and%20Preliminary%20Financial%20Information) This section details the public disclosure of the License Agreement and provides preliminary unaudited financial estimates for Q3 2025 [Regulation FD Disclosure](index=3&type=section&id=Regulation%20FD%20Disclosure) On October 16, 2025, Dianthus made a presentation publicly available on its investor relations website, announcing the License Agreement in conjunction with an investor conference call. This presentation is filed as Exhibit 99.1 - On October 16, 2025, Dianthus made a presentation publicly available on its investor relations website, announcing the execution of the License Agreement[14](index=14&type=chunk) - The presentation was in connection with a conference call with investors held at 8:00 a.m. ET on October 16, 2025, and is filed as Exhibit 99.1[14](index=14&type=chunk) [Preliminary Financial Information for the Three Months Ended September 30, 2025](index=5&type=section&id=Preliminary%20Financial%20Information%20for%20the%20Three%20Months%20Ended%20September%2030,%202025) Dianthus disclosed preliminary estimated cash, cash equivalents, and investments of approximately $555 million as of September 30, 2025. Pro forma cash, after deducting $30 million in upfront and near-term milestone payments to Leads, is estimated at $525 million. This information is unaudited and subject to change Preliminary Cash and Investments | Financial Metric | Amount (as of Sept 30, 2025) | | :--------------- | :--------------------------- | | Estimated Cash, Cash Equivalents and Investments | ~**$555 million** | | Pro Forma Cash, Cash Equivalents and Investments | ~**$525 million** (after deducting $30 million in upfront and near-term milestone payments to Leads) | - The disclosed financial information is preliminary, has not been audited, and is subject to change pending completion of the Company's unaudited financial statements[15](index=15&type=chunk) - The Company's independent registered public accounting firm has not audited, reviewed, or performed any procedures with respect to this preliminary information and does not express an opinion or any other form of assurance[15](index=15&type=chunk) [Forward-Looking Statements](index=5&type=section&id=Forward-Looking%20Statements) This section contains a standard disclaimer regarding forward-looking statements, emphasizing that they are based on current estimates and assumptions, subject to various risks and uncertainties, and actual results may differ materially. The company claims Safe Harbor protection and disclaims any obligation to update these statements, except as required by law - This report contains 'forward-looking statements' regarding expected financial results and the License Agreement, identified by specific terminology[16](index=16&type=chunk) - These statements are based on current estimates and assumptions, subject to various risks and uncertainties, many beyond the Company's control, and actual results could be materially different[16](index=16&type=chunk) - The Company claims the protection of the Safe Harbor contained in the Private Securities Litigation Reform Act of 1995 for forward-looking statements and disclaims any obligation to update or alter any statements, except as required by law[16](index=16&type=chunk) [Item 9.01 Financial Statements and Exhibits](index=5&type=section&id=Item%209.01%20Financial%20Statements%20and%20Exhibits) This item lists the exhibits filed as part of this Form 8-K, including the Company Presentation and the Cover Page Interactive Data File Filed Exhibits | Exhibit No. | Description | | :---------- | :---------- | | 99.1 | Company Presentation, dated October 16, 2025 | | 104 | Cover Page Interactive Data File (embedded within the inline XBRL document) | [SIGNATURES](index=6&type=section&id=SIGNATURES) This section confirms the official signing of the report on behalf of Dianthus Therapeutics, Inc. by an authorized officer - The report was signed on October 16, 2025, by Adam M. Veness, Esq., SVP, General Counsel and Secretary of Dianthus Therapeutics, Inc.[21](index=21&type=chunk)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from _________________ to _________________ Commission File Number: 001-38541 Dianthus Therapeutics, Inc. (Exact Name of Registrant as Specified in its Charter) | Del ...

Exhibit 99.1 DIANTHUS THERAPEUTICS HIGHLIGHTS RECENT BUSINESS ACHIEVEMENTS AND REPORTS Q2 FINANCIAL RESULTS Phase 2 MaGic trial of claseprubart (DNTH103) in generalized Myasthenia Gravis (gMG) top-line results anticipated in September 2025; the first of three catalysts for the claseprubart neuromuscular franchise by YE'26 Phase 3 CAPTIVATE trial of claseprubart in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) ongoing; interim responder analysis anticipated in 2H'26 Phase 2 MoMeNtum trial of clase ...

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 10-Q (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 | Delaware | 81-0724163 | | --- | --- | | (State or other jurisdiction of | (I.R.S. Employer | | incorporation or organization) | Identification No.) | | 7 Times Square, 43rd Floor | | | New York, New York | 10036 | | (Address of principal executive offices) | (Zip Code) | | Registran ...

Exhibit 99.1 DIANTHUS THERAPEUTICS HIGHLIGHTS RECENT BUSINESS ACHIEVEMENTS AND REPORTS Q1 FINANCIAL RESULTS Completed enrollment in Phase 2 MaGic trial of DNTH103 in generalized Myasthenia Gravis (gMG)s Top-line MaGic results anticipated in September 2025 to be the first of three catalysts for the DNTH103 neuromuscular franchise by YE'26 Phase 3 CAPTIVATE trial of DNTH103 in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) ongoing; interim responder analysis anticipated in 2H'26 Phase 2 MoMeNtum tri ...