# EDGAR Filing Document

**Accession Number:** 0001690585
**File Stem:** 0001193125-26-097555
**Filing Date:** 2026-3
**Character Count:** 64858
**Document Hash:** aea9a90871758dca5791bb8f0f2f97c8
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001193125-26-097555.hdr.sgml**: 20260309

**ACCESSION NUMBER**: 0001193125-26-097555

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 37

**CONFORMED PERIOD OF REPORT**: 20260309

**ITEM INFORMATION**: Results of Operations and Financial Condition

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Other Events

**FILED AS OF DATE**: 20260309

**DATE AS OF CHANGE**: 20260309

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Dianthus Therapeutics, Inc. /DE/
- **CENTRAL INDEX KEY:** 0001690585
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **ORGANIZATION NAME:** 03 Life Sciences
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-38541
- **FILM NUMBER:** 26733174

**BUSINESS ADDRESS:**
- **STREET 1:** 7 TIMES SQUARE
- **STREET 2:** 43RD FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036
- **BUSINESS PHONE:** 929-999-4055

**MAIL ADDRESS:**
- **STREET 1:** 7 TIMES SQUARE
- **STREET 2:** 43RD FLOOR
- **CITY:** NEW YORK
- **STATE:** NY
- **ZIP:** 10036

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Magenta Therapeutics, Inc.
- **DATE OF NAME CHANGE:** 20161121

?xml version='1.0' encoding='ASCII'? 8-K

**UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549**

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## FORM 8-K

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**CURRENT REPORT**

**Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934**

**Date of Report (Date of earliest event reported):** March 9, 2026<br>

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DIANTHUS THERAPEUTICS, INC.

**(Exact name of Registrant as Specified in Its Charter)**

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---

| | | |
|:---|:---|:---|
| Delaware | 001-38541 | 81-0724163 |
| **(State or Other Jurisdiction<br>of Incorporation)** | **(Commission File Number)** | **(IRS Employer<br>Identification No.)** |
| 7 Times Square<br>43rd Floor |  |  |
| New York**,** New York |  | 10036 |
| **(Address of Principal Executive Offices)** |  | **(Zip Code)** |

---

**Registrant's Telephone Number, Including Area Code:** 929 999-4055<br>

**(Former Name or Former Address, if Changed Since Last Report)**

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Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

**Securities registered pursuant to Section 12(b) of the Act:**

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| | | |
|:---|:---|:---|
| **<br>Title of each class** | **Trading<br>Symbol(s)** | **<br>Name of each exchange on which registered** |
| Common Stock, $0.001 Par Value | DNTH | The Nasdaq Capital Market |

---

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§ 230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§ 240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

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## Item 2.02 Results of Operations and Financial Condition.
On March 9, 2026, Dianthus Therapeutics, Inc. (the "Company") issued a press release announcing the Company's financial results for the quarter and full year ended December 31, 2025. A copy of this press release is furnished as Exhibit 99.1 and is incorporated herein by reference.

The information in this Form 8-K (including Exhibit 99.1 attached hereto) is being furnished and shall not be deemed "filed" for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any filing by the Company, under the Securities Act of 1933, as amended (the "Securities Act"), or the Exchange Act, except as expressly set forth by specific reference in such filing.

## Item 7.01 Regulation FD Disclosure.
On March 9, 2026, the Company issued a press release announcing early GO decision following interim responder analysis in Phase 3 CAPTIVATE trial of claseprubart in chronic inflammatory demyelinating polyneuropathy. The Company will host a conference call and webcast today, Monday, March 9, 2026, at 8:00 am, Eastern Time, to discuss the results.

A copy of the press release is furnished as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated by reference herein. The exhibit furnished under Item 7.01 of this Current Report on Form 8-K shall not be deemed to be "filed" for purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Exchange Act or the Securities Act, regardless of any general incorporation language in such filing.

## Item 8.01 Other Events.
On March 9, 2026, the Company made publicly available a data presentation announcing early GO decision following interim responder analysis in Phase 3 CAPTIVATE trial of claseprubart in chronic inflammatory demyelinating polyneuropathy (the "Presentation") on the investor relations section of its website. The Presentation is filed as Exhibit 99.3 and is incorporated by reference into this Item 8.01.

## Item 9.01 Financial Statements and Exhibits.
(d) Exhibits

---

| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| 99.1 | [<u>Press release, dated March 9, 2026</u>](dnth-ex99_1.htm) |
| 99.2 | [<u>Data press release, dated March 9, 2026</u>](dnth-ex99_2.htm) |
| 99.3 | [<u>Data presentation, dated March 9, 2026</u>](dnth-ex99_3.htm) |
| 104 | Cover Page Interactive Data File (embedded within the inline XBRL document) |

---

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**SIGNATURES**

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

---

| | | | |
|:---|:---|:---|:---|
|  |  |  | **DIANTHUS THERAPEUTICS, INC.** |
| Date: | March 9, 2026 | By:  | /s/ Adam M. Veness, Esq. |
|  |  |  | Adam M. Veness, Esq.<br>SVP, General Counsel and Secretary |

---

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## Exhibit 99.1

**Exhibit 99.1**

# ![img85518887_0.gif](img85518887_0.gif)

# DIANTHUS THERAPEUTICS HIGHLIGHTS RECENT BUSINESS ACHIEVEMENTS, INCLUDING GO DECISION FOR PHASE 3 CAPTIVATE CIDP TRIAL,

# AND REPORTS Q4 AND FY 2025 FINANCIAL RESULTS
*Early GO decision reached in CAPTIVATE ahead of Q2'26 guidance based on GO criteria of 20 confirmed responders achieved with less than 40 planned participants completing open-label Part A* 

*Phase 3 registrational trial of claseprubart evaluating 300mg/2mL Q2W and 300mg/2mL Q4W in generalized Myasthenia Gravis (gMG) expected to initiate in mid-2026; top-line results anticipated in 2H'28*

*Phase 2 MoMeNtum trial of claseprubart in Multifocal Motor Neuropathy (MMN) ongoing;* 

*top-line results on track for 2H'26*

*Phase 1 healthy volunteer data for DNTH212 anticipated in 2H'26; update on indication prioritization planned for 1H'26*

*$514.4 million of cash as of December 31, 2025 provides runway into 2028*

*Investor conference call and webcast to be held to discuss the CAPTIVATE trial interim responder analysis today, March 9, 2026 at 8:00 a.m. ET* 

**New York City and Waltham, Mass., March 9, 2026** – Dianthus Therapeutics, Inc. (Nasdaq: DNTH), a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases, today reported financial results for the fourth quarter and full year ending December 31, 2025, announced a GO decision in the Phase 3 CAPTIVATE trial of claseprubart in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP), and provided an update on other recent business achievements.

"It is truly exciting to be part of a company developing potential best-in-disease therapies for patients suffering from severe autoimmune diseases. I am very proud of the impressive level of execution the Dianthus team continues to deliver against our ambitious goals," said Marino Garcia, Chief Executive Officer of Dianthus Therapeutics. "With claseprubart, we are building a leading neuromuscular franchise with a target product profile that aims to combine best-in-class efficacy and safety with the convenience of an infrequent, subcutaneous, self-administered autoinjector that has the potential to meaningfully shift the treatment paradigm and standard of care for more than 150,000 patients in the U.S. living with gMG, CIDP and MMN."

**<u>Claseprubart (DNTH103) Clinical Development</u>**

Claseprubart is an investigational, clinical-stage, potent monoclonal antibody engineered to selectively target the classical pathway by inhibiting only the active form of the C1s protein, a clinically validated complement target. Claseprubart is designed to enable a more convenient, subcutaneous (S.C.), self-administered injection dosed as infrequently as once every two or four weeks. Claseprubart has the potential to be a best-in-class pipeline-in-a-product across a range of autoimmune disorders with high unmet need.

**Generalized Myasthenia Gravis (gMG)**

• **Phase 3 trial expected to initiate mid-2026, with top-line results expected in 2H'28:** Following the successful completion of our end-of-Phase 2 meeting with the FDA in the first quarter of 2026, a Phase 3

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registrational trial of claseprubart evaluating 300mg/2mL Q2W S.C. and 300mg/2mL Q4W S.C. in gMG patients is expected to initiate in mid-2026, with top-line results expected in 2H'28.

• **Claseprubart data presented at <u>Muscular Dystrophy Association (MDA) Clinical and Scientific Conference</u>, March 8-11, 2026:** Three poster presentations describing claseprubart Phase 2 MaGic results and *in vitro* data are available on the Investors section of the Dianthus website under <u>Scientific Publications</u>.

**Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)**

• **Early GO decision announced in Phase 3 <u>CAPTIVATE trial</u>:** The target for the Part A interim responder analysis was a response rate of 50% or greater (i.e., ≥20 confirmed responders out of first 40 participants to complete Part A) based on precedent set with aC1s inhibition. This GO decision was reached early, after 20 confirmed responders were achieved with less than 40 planned participants completing open-label Part A of the trial. Dianthus expects to provide CAPTIVATE Part B top-line guidance by YE'26.

**Multifocal Motor Neuropathy (MMN)**

• **Phase 2 MoMeNtum MMN trial remains on track for top-line results in 2H'26:** The <u>MoMeNtum trial</u> is an ongoing global, randomized, double-blind, placebo-controlled Phase 2 trial in patients with MMN.

**<u>DNTH212 Clinical Development</u>**

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. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes.

• **Phase 1 data anticipated in 2H'26:** A two-part Phase 1 study in China in healthy volunteers (Part A) and patients with systemic lupus erythematosus (Part B) was initiated in December 2025, with top-line results in healthy volunteers expected in 2H'26. An update on indication prioritization for DNTH212 is planned for 1H'26.

**<u>Full Year 2025 Financial Results</u>** 

• **Cash Position** – $514.4 million of cash, cash equivalents and investments as of December 31, 2025 is projected to provide runway into 2028.

• **R&D Expenses** – Research and development (R&D) expenses for the year ended December 31, 2025 were $145.6 million, inclusive of $10.1 million of stock-based compensation, compared to $83.1 million for the year ended December 31, 2024, which included $5.6 million of stock-based compensation. This increase in R&D expenses was primarily driven by higher clinical costs, upfront and clinical development milestones for DNTH212, and increased headcount to support claseprubart Phase 2 and Phase 3 development.

• **G&A Expenses** – General and administrative (G&A) expenses for the year ended December 31, 2025 totaled $34.3 million, inclusive of stock-based compensation of $12.7 million, compared to $25.0 million for the year ended December 31, 2024, which included $7.3 million of stock-based compensation. This increase in G&A expenses was primarily due to increased headcount.

• **Net Loss** – Net loss for the year ended December 31, 2025 was $162.3 million or $4.20 per share (basic and diluted) compared to $85.0 million or $2.55 per share (basic and diluted) for the year ended December 31, 2024.

• **Additional Information** – For additional information on the Company's financial results for the year ended December 31, 2025, please refer to the Form 10-K filed with the SEC.

www.dianthustx.com 7 Times Square, Floor 43 New York, NY 10036

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**CAPTIVATE Investor Conference Call & Webcast to be Held at 8:00 a.m. ET Today**

Dianthus Therapeutics will host an investor call and webcast to discuss the CAPTIVATE trial interim responder analysis today, March 9, 2026 at 8:00 a.m. ET. To access the live conference call by phone, please register <u>here</u>. Conference call participants in the question and answer session should pre-register to receive the dial-in number and personal PIN.

The <u>live webcast</u> may be accessed via the Investors section of the Dianthus Therapeutics website at <u>https://investor.dianthustx.com/</u>. A replay of the webcast will be available following the call. The presentation that will be used on this webcast is available <u>here</u>.

**About Claseprubart (DNTH103)**<br>Claseprubart is an investigational, clinical-stage, potent monoclonal antibody engineered to selectively target the classical pathway by inhibiting only the active form of the C1s protein, a clinically validated complement target. Claseprubart is enhanced with YTE half-life extension technology designed to enable a more convenient subcutaneous, infrequently dosed, self-administered injection. Additionally, selective inhibition of the classical complement pathway may lower patient risk of infection from encapsulated bacteria by preserving immune activity of the lectin and alternative pathways. As the classical pathway plays a significant role in disease pathology, claseprubart has the potential to be a best-in-class pipeline-in-a-product across a range of autoimmune disorders with high unmet need. Dianthus is building a neuromuscular franchise with claseprubart and expects to initiate a Phase 3 trial in generalized Myasthenia Gravis in mid-2026, with top-line results expected in 2H'28, report top-line data from the Phase 2 MoMeNtum trial in Multifocal Motor Neuropathy in 2H'26, and provide an update on timing of top-line data from Part B of the Phase 3 CAPTIVATE trial in Chronic Inflammatory Demyelinating Polyneuropathy by YE'26.

Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide.

**About DNTH212**<br>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. By targeting both the innate and adaptive immune systems via two clinically validated pathways that are known drivers of autoimmune disease pathogenesis, this complementary and differentiated approach has the potential to address multiple autoimmune indications with improved outcomes. A two-part Phase 1 study in China in healthy volunteers (Part A) and patients with systemic lupus erythematosus (Part B) is ongoing, with top-line results in healthy volunteers expected in 2H'26.

DNTH212 is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide.

**About Dianthus Therapeutics**

Dianthus Therapeutics, Inc. is a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases. Based in New York City and Waltham, Mass., Dianthus is comprised of an experienced team of biotech and pharma executives who aim to deliver transformative medicines for people living with severe autoimmune and inflammatory diseases.

To learn more, please visit <u>www.dianthustx.com</u> and follow us on <u>LinkedIn</u>.

www.dianthustx.com 7 Times Square, Floor 43 New York, NY 10036

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**Cautionary Statement Regarding Forward-Looking Statements** 

Certain statements in this press release, other than purely historical information, may constitute "forward-looking statements" within the meaning of the federal securities laws, including for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995, express or implied statements regarding future plans and prospects, including statements regarding the expectations or plans for discovery, preclinical studies, clinical trials and research and development programs, in particular with respect to claseprubart and DNTH212, and any developments or results in connection therewith, including the target product profile and administration of claseprubart and DNTH212; the anticipated timing of the initiation and results from those studies and trials; expectations regarding the clinical trial designs or indications; expectations regarding the time period over which the Company's capital resources are expected to be sufficient to fund its anticipated operations; and expectations regarding market size, patient population size, and potential opportunities for complement therapies, in particular with respect to claseprubart and DNTH212. Claseprubart and DNTH212 are investigational agents that are not approved as therapies in any indication in any jurisdiction worldwide. The words "opportunity," "potential," "milestones," "runway," "will," "anticipate," "achieve," "near-term," "catalysts," "pursue," "pipeline," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "predict," "project," "should," "strive," "would," "aim," "target," "commit," and similar expressions (including the negatives of these terms or variations of them) generally identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking.

Actual results could differ materially from those included in the forward-looking statements due to various factors, risks and uncertainties, including, but not limited to, that preclinical testing of claseprubart and DNTH212 and data from clinical trials may not be predictive of the results or success of ongoing or later clinical trials, that the preliminary interim analysis based on a limited number of patients from the Part A open label portion of the claseprubart CAPTIVATE study in patients with CIDP may not be predictive of the results or success of the remaining patients treated in Part A or patients treated in Part B of the CAPTIVATE study, that the development of claseprubart or DNTH212 may take longer and/or cost more than planned, that the Company or its partner may be unable to successfully complete the clinical development of the Company's compounds, that the Company or its partner may be delayed in initiating, enrolling or completing its planned clinical trials, and that the Company's compounds may not receive regulatory approval or become commercially successful products. These and other risks and uncertainties are identified under the heading "Risk Factors" included in the Company's Annual Report on Form 10-K for the period ended December 31, 2025, and other filings that the Company has made and may make with the SEC in the future. Nothing in this press release should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved.

The forward-looking statements in this press release speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Dianthus undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law.

**Contact** 

Jennifer Davis Ruff

Dianthus Therapeutics

<u>jdavisruff@dianthustx.com</u>

www.dianthustx.com 7 Times Square, Floor 43 New York, NY 10036

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**DIANTHUS THERAPEUTICS, INC.** 

**Consolidated Balance Sheets** 

**(unaudited, in thousands)** 

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| | | |
|:---|:---|:---|
|  | **December 31,** | **December 31,** |
|  | **2025** | **2024** |
| **Assets** |  |  |
| Current assets: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Cash and cash equivalents | $51087 | $22792 |
| &nbsp;&nbsp;&nbsp;&nbsp;Short-term investments | 353208 | 252449 |
| &nbsp;&nbsp;&nbsp;&nbsp;Receivable from former related party |  | 807 |
| &nbsp;&nbsp;&nbsp;&nbsp;Accounts receivable, net | 52 |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Prepaid expenses and other current assets | 5091 | 4856 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total current assets | 409438 | 280904 |
| Long-term investments | 110135 | 81728 |
| Property and equipment, net | 296 | 194 |
| Right-of-use operating lease assets | 1337 | 1553 |
| Other assets and restricted cash | 9716 | 9629 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total assets | $530922 | $374008 |
| **Liabilities and Stockholders' Equity** |  |  |
| Current liabilities: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Accounts payable | $9725 | $4579 |
| &nbsp;&nbsp;&nbsp;&nbsp;Accrued expenses | 19452 | 13074 |
| &nbsp;&nbsp;&nbsp;&nbsp;Current portion of deferred revenue | 1188 | 479 |
| &nbsp;&nbsp;&nbsp;&nbsp;Current portion of operating lease liabilities | 367 | 320 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total current liabilities | 30732 | 18452 |
| Deferred revenue | 5770 | 1908 |
| Long-term operating lease liabilities | 1019 | 1171 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total liabilities | 37521 | 21531 |
| Commitments and contingencies |  |  |
| Stockholders' equity: |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Preferred stock |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;Common stock | 43 | 31 |
| &nbsp;&nbsp;&nbsp;&nbsp;Additional paid-in capital | 829598 | 526732 |
| &nbsp;&nbsp;&nbsp;&nbsp;Accumulated deficit | (336729) | (174392) |
| &nbsp;&nbsp;&nbsp;&nbsp;Accumulated other comprehensive income | 489 | 106 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total stockholders' equity | 493401 | 352477 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total liabilities and stockholders' equity | $530922 | $374008 |

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www.dianthustx.com 7 Times Square, Floor 43 New York, NY 10036

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| | | | | |
|:---|:---|:---|:---|:---|
| &nbsp;&nbsp;**Dianthus Therapeutics, Inc.** | &nbsp;&nbsp;**Dianthus Therapeutics, Inc.** | &nbsp;&nbsp;**Dianthus Therapeutics, Inc.** | &nbsp;&nbsp;**Dianthus Therapeutics, Inc.** | &nbsp;&nbsp;**Dianthus Therapeutics, Inc.** |
| &nbsp;&nbsp;**Consolidated Statements of Operations and Comprehensive Loss** | &nbsp;&nbsp;**Consolidated Statements of Operations and Comprehensive Loss** | &nbsp;&nbsp;**Consolidated Statements of Operations and Comprehensive Loss** | &nbsp;&nbsp;**Consolidated Statements of Operations and Comprehensive Loss** | &nbsp;&nbsp;**Consolidated Statements of Operations and Comprehensive Loss** |
| &nbsp;&nbsp;**(unaudited, in thousands, except share and per share data)** | &nbsp;&nbsp;**(unaudited, in thousands, except share and per share data)** | &nbsp;&nbsp;**(unaudited, in thousands, except share and per share data)** | &nbsp;&nbsp;**(unaudited, in thousands, except share and per share data)** | &nbsp;&nbsp;**(unaudited, in thousands, except share and per share data)** |
|  | &nbsp;&nbsp;**Three Months Ended** <br>**December 31,** | &nbsp;&nbsp;**Three Months Ended** <br>**December 31,** | &nbsp;&nbsp;**Year Ended** <br>**December 31,** | &nbsp;&nbsp;**Year Ended** <br>**December 31,** |
|  | &nbsp;&nbsp;**2025** | &nbsp;&nbsp;**2024** | &nbsp;&nbsp;**2025** | &nbsp;&nbsp;**2024** |
| &nbsp;&nbsp;**Revenues:** |  |  |  |  |
| &nbsp;&nbsp;License revenue – related party | &nbsp;&nbsp;$—  | &nbsp;&nbsp;$999  | &nbsp;&nbsp;$— | &nbsp;&nbsp;$5909  |
| &nbsp;&nbsp;License revenue | &nbsp;&nbsp;284 | &nbsp;&nbsp;326 | &nbsp;&nbsp;2036 | &nbsp;&nbsp;326 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Total revenues | &nbsp;&nbsp;284 | &nbsp;&nbsp;1325 | &nbsp;&nbsp;2036 | &nbsp;&nbsp;6235 |
| &nbsp;&nbsp;**Operating expenses:** |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Research and development | &nbsp;&nbsp;59895  | &nbsp;&nbsp;26413  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;145638  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;83105  |
| &nbsp;&nbsp;&nbsp;General and administrative | &nbsp;&nbsp;9930  | &nbsp;&nbsp;6828  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;34331  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;24994  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total operating expenses | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;69825  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;33241  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;179969  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;108099  |
| &nbsp;&nbsp;Loss from operations | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (69541) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (31916) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (177933) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (101864) |
| &nbsp;&nbsp;Other income/(expense): |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Interest and investment income | &nbsp;&nbsp;5267  | &nbsp;&nbsp;3991  | &nbsp;&nbsp;16119  | &nbsp;&nbsp;17365  |
| &nbsp;&nbsp;&nbsp;Gain/(loss) on investment in related party | &nbsp;&nbsp;254 | &nbsp;&nbsp;(160) | &nbsp;&nbsp;508 | &nbsp;&nbsp;148 |
| &nbsp;&nbsp;&nbsp;Gain/(loss) on currency exchange, net | &nbsp;&nbsp;(3) | &nbsp;&nbsp;27 | &nbsp;&nbsp;(57) | &nbsp;&nbsp;(64) |
| &nbsp;&nbsp;&nbsp;Other expense | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (409) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (380) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (974) | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (554) |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total other income | &nbsp;&nbsp;5109 | &nbsp;&nbsp;3478 | &nbsp;&nbsp;15596 | &nbsp;&nbsp;16895 |
| &nbsp;&nbsp;Net loss | &nbsp;&nbsp;$(64432) | &nbsp;&nbsp;$(28438) | &nbsp;&nbsp;$(162337) | &nbsp;&nbsp;$(84969) |
| &nbsp;&nbsp;Net loss per share attributable to common stockholders, basic and diluted | &nbsp;&nbsp;$(1.43) | &nbsp;&nbsp;$(0.81) | &nbsp;&nbsp;$(4.20) | &nbsp;&nbsp;$(2.55) |
| &nbsp;&nbsp;Weighted-average number of shares of common stock outstanding including shares issuable under equity-classified pre-funded warrants, used in computing net loss per share of common stock, basic and diluted | &nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 44971383  | &nbsp;&nbsp; <br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 35033773  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;38617580  | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;33313849  |
| &nbsp;&nbsp;Comprehensive loss: |  |  |  |  |
| &nbsp;&nbsp;&nbsp;Net Loss | &nbsp;&nbsp;$(64432) | &nbsp;&nbsp;$(28438) | &nbsp;&nbsp;$(162337) | &nbsp;&nbsp;$(84969) |
| &nbsp;&nbsp;&nbsp;Other comprehensive income/(loss): |  |  |  |  |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Unrealized gain/(loss) on marketable securities | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 326 | &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (575) | &nbsp;&nbsp;383 | &nbsp;&nbsp;59 |
| &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Total other comprehensive income/(loss) | &nbsp;&nbsp;326 | &nbsp;&nbsp;(575) | &nbsp;&nbsp;383 | &nbsp;&nbsp;59 |
| &nbsp;&nbsp;Total comprehensive loss | &nbsp;&nbsp;$(64106) | &nbsp;&nbsp;$(29013) | &nbsp;&nbsp;$(161954) | &nbsp;&nbsp;$(84910) |

---

www.dianthustx.com 7 Times Square, Floor 43 New York, NY 10036

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## Exhibit 99.2

**Exhibit 99.2**

# ![img86442408_0.gif](img86442408_0.gif)

# DIANTHUS THERAPEUTICS ANNOUNCES EARLY GO DECISION FOLLOWING INTERIM RESPONDER ANALYSIS IN PHASE 3 CAPTIVATE TRIAL OF CLASEPRUBART IN CHRONIC INFLAMMATORY DEMYELINATING POLYNEUROPATHY (CIDP)
*Early GO decision reached ahead of Q2'26 guidance based on GO criteria of 20 confirmed responders achieved with less than 40 planned participants completing open-label Part A* 

*Key objectives achieved: Company will maintain the Part A dose of 300mg/2mL S.C. Q2W, plans to engage with regulators to remove the 600mg/4mL S.C. Q2W dose arm from Part B, and expects to enroll up to 256 patients in Part A to randomize 128 patients in Part B*

*Independent DSMB review confirmed GO decision; no related serious infections, no clinical symptoms of autoimmune activation, and no related serious adverse events or discontinuations* 

*GO decision supports continued development of claseprubart 300mg/2mL Q2W S.C. in CIDP, targeting a potentially best-in-disease biologic profile across a broad population of CIDP patients, including those refractory to standard-of-care*

*Investor conference call and webcast to be held today, March 9, 2026 at 8:00 a.m. ET* 

**New York City and Waltham, Mass., March 9, 2026** – Dianthus Therapeutics, Inc. (Nasdaq: DNTH), a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases, today announced an early GO decision based on an interim responder analysis in the <u>Phase 3 CAPTIVATE trial</u> of claseprubart in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP).

"We are excited to announce an early GO decision based on results from less than 40 planned participants completing Part A of the CAPTIVATE Phase 3 trial. These interim responder analysis results, in addition to the robust Phase 2 data from our MaGic trial in generalized Myasthenia Gravis, bolster our confidence in the best-in-class target profile for claseprubart and its potential to become a best-in-disease, first-line biologic of choice across a range of large and growing neuromuscular indications," said Marino Garcia, Chief Executive Officer of Dianthus. "Classical pathway inhibition could replace the standard of care in the multi-billion-dollar CIDP market with the potential for improved efficacy, differentiated safety, and lower patient burden. We expect our planned study design changes to streamline the CAPTIVATE trial and support even faster execution."

**Interim Responder Analysis Results Summary**

• The target for the Part A interim responder analysis was a response rate of 50% or greater (i.e., ≥20 confirmed responders out of first 40 participants to complete Part A) based on precedent set with aC1s inhibition.

• This GO decision was reached early, after 20 confirmed responders were achieved with less than 40 planned participants completing Part A of the trial.

• There have been no related serious infections, no clinical symptoms of autoimmune activation, no related serious adverse events or discontinuations.

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• The GO decision was confirmed by an independent DSMB review.

**Next Steps: Planned CAPTIVATE Trial Design Updates**

Dianthus anticipates the following:

• Maintain the claseprubart 300mg/2mL S.C. Q2W dose in Part A;

• Engage with regulators to remove the claseprubart 600mg/4mL S.C. Q2W arm from Part B;

• Enroll up to 256 patients (previously up to 480) in Part A to randomize 128 patients in Part B (previously 192); and

• Provide CAPTIVATE Part B top-line guidance by the end of 2026.

"As a neurologist who specialized in and treated many patients with neuromuscular diseases including CIDP, it is encouraging to see consistency across multiple clinically meaningful measures including INCAT, MRC-SS, Grip Strength, and IRODS in Part A of the CAPTIVATE study," said James K. Sheffield, MD, Vice President and Head of CIDP Development of Dianthus. "These initial findings motivate the CIDP team to get to primary results as soon as possible."

**About CAPTIVATE**

<u>CAPTIVATE</u> is a single, two-part, randomized withdrawal Phase 3 trial of claseprubart in CIDP. In open-label Part A of this trial, participants are administered a loading dose followed by 300mg claseprubart administered every 2 weeks (Q2W) via subcutaneous (S.C.) injection for up to 13 weeks. Part A included an interim responder analysis of a pre-defined number of participants. The primary endpoint in Part A is response as measured as ≥1 point decrease (improvement) in adjusted INCAT score compared to Part A baseline. Only participants who respond to claseprubart in Part A will be randomized into Part B, a double-blind, placebo-controlled treatment period of up to 52 weeks, where they will be assessed for prevention of relapse, safety and tolerability, followed by an open-label extension period. The primary endpoint in Part B is efficacy (time to relapse) as measured as ≥1 point increase in adjusted INCAT. The Company believes this single pivotal trial will support Biologics License Application filing in adult patients with CIDP and expects to provide CAPTIVATE Part B top-line guidance by the end of 2026.

**CAPTIVATE Investor Conference Call & Webcast to be Held at 8:00 a.m. ET Today**

Dianthus Therapeutics will host an investor call and webcast to discuss the CAPTIVATE trial interim responder analysis today, March 9, 2026 at 8:00 a.m. ET. To access the live conference call by phone, please register <u>here</u>. Conference call participants in the question and answer session should pre-register to receive the dial-in number and personal PIN.

The <u>live webcast</u> may be accessed via the Investors section of the Dianthus Therapeutics website at <u>https://investor.dianthustx.com/</u>. A replay of the webcast will be available following the call. The presentation that will be used on this webcast is available here**.**

**About Claseprubart (DNTH103)**<br>Claseprubart is an investigational, clinical-stage, potent monoclonal antibody engineered to selectively target the classical pathway by inhibiting only the active form of the C1s protein, a clinically validated complement target. Claseprubart is enhanced with YTE half-life extension technology designed to enable a more convenient subcutaneous, infrequently dosed, self-administered injection. Additionally, selective inhibition of the classical complement pathway may lower patient risk of infection from encapsulated bacteria by preserving immune activity of the lectin and alternative pathways. As the classical pathway plays a significant role in disease pathology, claseprubart has the potential to be a best-in-class pipeline-in-a-product across a range of

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autoimmune disorders with high unmet need. Dianthus is building a neuromuscular franchise with claseprubart and expects to initiate a Phase 3 trial in generalized Myasthenia Gravis in mid-2026, with top-line results expected in the second half of 2028, report top-line data from the Phase 2 MoMeNtum trial in Multifocal Motor Neuropathy in the second half of 2026, and provide an update on timing of top-line data from Part B of the Phase 3 CAPTIVATE trial in Chronic Inflammatory Demyelinating Polyneuropathy by the end of 2026.

Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide.

**About CIDP**

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is an autoimmune and inflammatory disorder affecting the myelin that insulates and protects peripheral nerves. CIDP is estimated to affect more than 40,000 people in the United States. Common symptoms of the disease include weakness, loss of balance, and sensation changes in the arms or legs. In the classic or typical CIDP, there is symmetric involvement of both upper and lower limbs, characterized by weakness in the proximal (for example, shoulder region or hip region) as well as distal (for example, wrist or ankle) muscle groups. In addition, there is sensory involvement. There are several atypical forms of CIDP, characterized by varying levels of motor and sensory involvement with overlap. CIDP follows a relapsing-remitting or a progressive clinical course, which can result in substantial disability, loss of motor and sensory function, and negative impact on quality of life.

**About Dianthus Therapeutics**

Dianthus Therapeutics, Inc. is a clinical-stage biotechnology company dedicated to developing next-generation therapies to transform the treatment of severe autoimmune diseases. Based in New York City and Waltham, Mass., Dianthus is comprised of an experienced team of biotech and pharma executives who aim to deliver transformative medicines for people living with severe autoimmune and inflammatory diseases.

To learn more, please visit <u>www.dianthustx.com</u> and follow us on <u>LinkedIn</u>.

**Cautionary Statement Regarding Forward-Looking Statements**

Certain statements in this press release, other than purely historical information, may constitute "forward-looking statements" within the meaning of the federal securities laws, including for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995, express or implied statements regarding future plans and prospects, including statements regarding the expectations or plans for discovery, preclinical studies, clinical trials and research and development programs, in particular with respect to claseprubart, and any developments or results in connection therewith, including the target product profile and administration of claseprubart; the anticipated timing of the initiation and results from those studies and trials; expectations regarding the clinical trial designs or indications; and expectations regarding market size, patient population size, and potential opportunities for complement therapies, in particular with respect to claseprubart. Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide. The words "opportunity," "potential," "milestones," "runway," "will," "anticipate," "achieve," "near-term," "catalysts," "pursue," "pipeline," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "predict," "project," "should," "strive," "would," "aim," "target," "commit," and similar expressions (including the negatives of these terms or variations of them) generally identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking.

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Actual results could differ materially from those included in the forward-looking statements due to various factors, risks and uncertainties, including, but not limited to, that preclinical testing of claseprubart and data from clinical trials may not be predictive of the results or success of ongoing or later clinical trials, that the preliminary interim analysis based on a limited number of patients from the Part A open-label portion of the claseprubart CAPTIVATE study in patients with CIDP may not be predictive of the results or success of the remaining patients treated in Part A or patients treated in Part B of the CAPTIVATE study, that the development of claseprubart may take longer and/or cost more than planned, that the Company or its partner may be unable to successfully complete the clinical development of the Company's compounds, that the Company or its partner may be delayed in initiating, enrolling or completing its planned clinical trials, and that the Company's compounds may not receive regulatory approval or become commercially successful products. These and other risks and uncertainties are identified under the heading "Risk Factors" included in the Company's Annual Report on Form 10-K for the period ended December 31, 2025, and other filings that the Company has made and may make with the SEC in the future. Nothing in this press release should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved.

The forward-looking statements in this press release speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Dianthus undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law.

**Contact** 

Jennifer Davis Ruff

Dianthus Therapeutics

<u>jdavisruff@dianthustx.com</u>

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## Exhibit 99.3

![Slide 1](dnth-ex99_3s1.jpg)

Dianthus TherapeuticsEarly GO Decision in CAPTIVATE CIDP Trial March 9, 2026 Exhibit 99.3

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![Slide 2](dnth-ex99_3s2.jpg)

Forward-looking statements Certain statements in this presentation, other than purely historical information, may constitute "forward-looking statements" within the meaning of the federal securities laws, including for purposes of the safe harbor provisions under the United States Private Securities Litigation Reform Act of 1995, express or implied statements regarding future plans and prospects, including statements regarding the expectations or plans for discovery, preclinical studies, clinical trials and research and development programs, in particular with respect to claseprubart and DNTH212, and any developments or results in connection therewith, including the target product profile and administration of claseprubart and DNTH212; the anticipated timing of the initiation and results from those studies and trials; expectations regarding the clinical trial designs or indications; expectations regarding the time period over which the Company's capital resources are expected to be sufficient to fund its anticipated operations; and expectations regarding market size, patient population size, and potential opportunities for complement therapies, in particular with respect to claseprubart and DNTH212. Claseprubart and DNTH212 are investigational agents that are not approved as therapies in any indication in any jurisdiction worldwide. The words "opportunity," "potential," "milestones," "runway," "will," "anticipate," "achieve," "near-term," "catalysts," "pursue," "pipeline," "believe," "continue," "could," "estimate," "expect," "intend," "may," "might," "plan," "possible," "predict," "project," "should," "strive," "would," "aim," "target," "commit," and similar expressions (including the negatives of these terms or variations of them) generally identify forward-looking statements, but the absence of these words does not mean that statement is not forward looking. Actual results could differ materially from those included in the forward-looking statements due to various factors, risks and uncertainties, including, but not limited to, that preclinical testing of claseprubart and DNTH212 and data from clinical trials may not be predictive of the results or success of ongoing or later clinical trials, that the preliminary interim analysis based on a limited number of patients from the Part A open label portion of the claseprubart CAPTIVATE study in patients with chronic inflammatory demyelinating polyneuropathy may not be predictive of the results or success of the remaining patients treated in Part A or patients treated in Part B of the CAPTIVATE study, that the development of claseprubart or DNTH212 may take longer and/or cost more than planned, that the Company or its partner may be unable to successfully complete the clinical development of the Company's compounds, that the Company or its partner may be delayed in initiating, enrolling or completing its planned clinical trials, and that the Company's compounds may not receive regulatory approval or become commercially successful products. These and other risks and uncertainties are identified under the heading "Risk Factors" included in the Company's Annual Report on Form 10-K for the period ended December 31, 2025, and other filings that the Company has made and may make with the SEC in the future. Nothing in this presentation should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved. Nothing in this Presentation should be regarded as a representation by any person that the forward-looking statements set forth herein will be achieved or that any of the contemplated results of such forward-looking statements will be achieved. Dianthus undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law. This Presentation contains limited disclosure with respect to an interim responder analysis in the open-label Part A of the registrational claseprubart CAPTIVATE study. The level of detail in this Presentation is limited to preserve the integrity of the trial as a two-part registrational trial.

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![Slide 3](dnth-ex99_3s3.jpg)

Agenda Introduction Marino Garcia, Chief Executive Officer Early GO Decision in CAPTIVATE Simrat Randhawa, MD, Head of Research & Development Closing Remarks Marino Garcia, Chief Executive Officer Analyst Q&A Marino Garcia, Chief Executive Officer Simrat Randhawa, MD, Head of Research & Development John King, Chief Commercial Officer Ryan Savitz, Chief Financial Officer & Chief Business Officer

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![Slide 4](dnth-ex99_3s4.jpg)

Introduction Marino Garcia, CEO

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![Slide 5](dnth-ex99_3s5.jpg)

Interim Responder Analysis in CAPTIVATE was planned with first 40 patients completing Open-Label Part A Claseprubart 300mg/2mL S.C. Q2W (N=64) Placebo (N=64) Claseprubart 600mg/4mL S.C. Q2W (N=64) Screen PART A: Up to 13-Week Open-Label Claseprubart Only PART B: 52-Week Pbo- controlled RCT CIDP diagnosis confirmed by an Independent CIDP Review Panel (ICRP) Open-Label Extension: 104 Weeks Loading Dose Day 0 Interim Responder Analysis (N=40) Claseprubart 300mg/2mL S.C. Q2W (N= up to 480) Highlights Design: All subjects receive claseprubart in Part A for up to 13 weeks. Only responders randomized to Part B for 52 weeks Inclusion: ≥18 years old with confirmed CIDP, including SoC-Refractory, SoC-Treated or SoC-Naïve Dosing: I.V. loading dose followed by 300mg/2mL S.C. Q2W in Part A; followed by 300mg/2mL or 600mg/4mL or placebo in Part B Endpoints Part A: Response as measured as ≥1 point decrease (improvement) in adjusted INCAT score compared to Part A baseline Part B Primary: Efficacy (time to relapse) as measured as ≥1 point increase in adjusted INCAT Responders Randomized 1:1:1 to Part B Enrolling a broad patient population including SoC-refractory patients, in addition to SoC-Treated and SoC-Naïve patients No requirement for IVIg withdrawal and disease worsening, consistent with ongoing FcRn and complement CIDP studies Only responders from Part A randomized into the double-blind, placebo-controlled Part B Single pivotal two-part, randomized withdrawal, double-blind, placebo-controlled trial designed to support BLA in adult patients with CIDP Focus of Today CAPTIVATE Trial: https://clinicaltrials.gov/study/NCT06858579. Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide. Safety and efficacy for claseprubart has not been evaluated in head-to-head comparative clinical studies. Autoinjector for claseprubart administration is anticipated to be SHL Medical's Molly technology, patented or patent pending in the US, China, India, Japan, Korea, Taiwan and at the European Patent Office.

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![Slide 6](dnth-ex99_3s6.jpg)

Significant differences between CAPTIVATE and ADHERE Source: Company filings, presentations and clinicaltrials.gov. Ig refers to IVIg and SCIg Data are derived from different clinical trials conducted at different times, with differences in trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. ADHERE required discontinuation of IVIg or SCIg and evidence of clinically meaningful deterioration before dosing in Part A Defined as a clinical improvement on the parameters that the participant worsened in during run-in (≥4-point increase in I-RODS and/or ≥8-kPa increase in mean grip strength) or clinical improvement (≥1-point decrease) in INCAT Empasiprubart and riliprubart studies Considerations Efgartigimod (FcRn) S.C. QW Claseprubart (aC1s) 300mg/2mL S.C. Q2W Key Differentiators of CAPTIVATE Ph. 3 Study Populations Evaluating claseprubart in SoC-Refractory CIDP patients, in addition to a broader CIDP patient population including SoC-Treated and SoC-Naïve Require IVIg or SCIg Withdrawal and Relapse Prior to Enrolling in Part A of Study1 YES NO Immediate switch 7 days from last Ig dose to claseprubart; consistent with other ongoing complement CIDP studies3 Study Endpoints / Results Confirmed ECI2 Ph. 3 Stage A results: 66.5% ECI (wk 12) Switching Ig patients to claseprubart 7 days after last dose Aiming for ≥1-point adj. INCAT improvement OVER SoC/Ig in ≥50% of patients in Part A Part A designed to evaluate clinically meaningful improvement over Ig after immediate switch 7 days after last dose SoC-Treated Off Treatment SoC-Treated SoC-Naïve SoC-Refractory ~1/3 of pts did not return to pre-Ig washout baseline

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![Slide 7](dnth-ex99_3s7.jpg)

Active C1s inhibition with riliprubart has demonstrated clinical proof-of-concept across broad patient groups Claseprubart is being evaluated with a convenient, low volume dose of 300mg/2mL Q2W Riliprubart Phase 2 at PNS 2024 Based on riliprubart patent filing (Pg 76) Ph. 2 Riliprubart Data in Active C1s in CIDP1 with High Volume, Weekly Dosing of 600mg/4mL2 Data not seen with FcRns Improvement without Ig washout

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![Slide 8](dnth-ex99_3s8.jpg)

Targeting response rate of >50% (>20 responders) out of first 40 participants to complete Part A GO: However, increase dose as responder rate below precedent Less than 20 Responders 25% 30% 45% 55% 60% 65% 70% 75% 20 or More Responders Data from CAPTIVATE and riliprubart Ph. 2 are derived from different clinical trials conducted at different times, with differences in trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. Based on SoC-Refractory and SoC-Treated response rates from riliprubart Phase 2 posters; Riliprubart Phase 2 at AANEM 2023 and Riliprubart Phase 2 at PNS 2024 35% 40% 80% 85% 90% 100% Riliprubart Ph. 2 benchmark response rates: ~50%1 50% Interim Responder Rate in CAPTIVATE Part A GO: Keep dose 300mg/2mL Q2W as target responder rate met or exceeded 95%

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![Slide 9](dnth-ex99_3s9.jpg)

Early GO Decision in CAPTIVATE Simrat Randhawa, MD, Head of Research & Development

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![Slide 10](dnth-ex99_3s10.jpg)

Early GO decision reached with less than 40 planned participants completing Part A GO decision reached early after 20 confirmed responders were achieved with less than 40 planned participants completing Part A Independent DSMB reviewed the data to date and confirmed GO decision; no related serious infections, no clinical symptoms of autoimmune activation, no related SAEs or discontinuations GO decision supports continued development of claseprubart at 300mg/2mL Q2W S.C. in CIDP targeting a potentially best-in-disease biologic profile Safety / Tolerability Update CAPTIVATE Interim Analysis Objective Targeting response rate of 50% or greater (≥20 patients out of first 40 participants in Part A) based on precedent set with aC1s inhibition  GO Decision  CAPTIVATE Interim Analysis data cut off as of March 4, 2026

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![Slide 11](dnth-ex99_3s11.jpg)

CAPTIVATE Part A baseline patient group characteristics are similar to precedent aC1s Ph. 2 study1 Broad representation of patients across North America, Europe, and Asia in CAPTIVATE Part A Data from CAPTIVATE and riliprubart Ph. 2 are derived from different clinical trials conducted at different times, with differences in trial design and patient populations. As a result, cross-trial comparisons cannot be made, and no head-to-head clinical trials have been conducted. Riliprubart Phase 2 at PNS 2024 Includes only participants who have completed Part A. Data cut off as of March 4, 2026 CAPTIVATE2 Baseline Patient Group Characteristics ~69% SoC-Treated ~19% SoC-Refractory ~12% SoC- Naïve ~62% SoC-Treated ~23% SoC-Refractory ~15% SoC- Naïve Riliprubart Ph. 21 Baseline Patient Group Characteristics (N=78)

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![Slide 12](dnth-ex99_3s12.jpg)

Early responder rates support 300mg/2mL Q2W dose and updates to CAPTIVATE Trial Design Element Original Design Anticipated New Design Claseprubart CAPTIVATE Implications Part A Dose 300mg/2mL S.C. Q2W 300mg/2mL S.C. Q2W No change to Part A dose given results observed to date Study Arms in Part B 300mg/2mL Q2W (N=64) 600mg/4mL Q2W (N=64) Placebo (N=64) Total Part B Patients (N=192) 300mg/2mL Q2W (N=64) Placebo (N=64) Total Part B Patients (N=128) ~1/3 fewer total patients anticipated in Part B and potential faster execution to top-line results Estimated Enrollment in Part A Up to 480 patients, conservative 40% minimum responder rates Up to 256 patients, conservative 50% minimum responder rates Ratio from Part A to Part B changed due to responder rates seen across all patient groups CAPTIVATE Trial: https://clinicaltrials.gov/study/NCT06858579. Planned changes pending regulatory approval.

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![Slide 13](dnth-ex99_3s13.jpg)

PART B: 52-Week Pbo- controlled RCT Revised CAPTIVATE study design going forward Claseprubart 300mg/2mL S.C. Q2W (N=64) Placebo (N=64) Screen PART A: Up to 13-Week Open-Label Claseprubart Only CIDP diagnosis confirmed by an Independent CIDP Review Panel (ICRP) Open-Label Extension: 104 Weeks Loading Dose Day 0 Claseprubart 300mg/2mL S.C. Q2W (N= up to 256) CAPTIVATE Trial: https://clinicaltrials.gov/study/NCT06858579. Planned changes pending regulatory approval. Highlights Design: All subjects receive claseprubart in Part A for up to 13 weeks. Only responders randomized to Part B for 52 weeks Inclusion: ≥18 years old with confirmed CIDP, including SoC-Refractory, SoC-Treated or SoC-Naïve Dosing: I.V. loading dose followed by 300mg/2mL S.C. Q2W in Part A; followed by 300mg/2mL or placebo in Part B Endpoints Part A: Response as measured as ≥1 point decrease (improvement) in adjusted INCAT score compared to Part A baseline Part B Primary: Efficacy (time to relapse) as measured as ≥1 point increase in adjusted INCAT Responders Randomized 1:1 to Part B Planned changes pending regulatory approval Part A N= up to 256 Part B N=128 Ratio of Part A to Part B changed from a conservative 40% to a conservative 50%

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![Slide 14](dnth-ex99_3s14.jpg)

Closing Remarks Marino Garcia, CEO

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![Slide 15](dnth-ex99_3s15.jpg)

Today's update continues to build on the promise of claseprubart to be a potential pipeline-in-a-product and best-in-class therapy in growing and underserved markets CAPTIVATE Part A Early GO Decision in CIDP Ph.2 MaGic Showed Rapid & Robust Improvements in gMG Q3'25 Q1'26

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![Slide 16](dnth-ex99_3s16.jpg)

US CIDP market offers substantial growth potential given high unmet need and limitations of current standard of care Opportunity for an active C1s inhibitor with the target profile of claseprubart to replace the standard of care Current Ig and biologics account for >$3.5B5,6 Despite SoC, many (30-50%) patients are refractory, face risk of relapse, and confront adverse effects of long-term treatment7-9 FcRn is considered more of an alternative than improvement over IVIg10 Active C1s inhibition has demonstrated ~50% improvement in both SoC-Treated and SoC-Refractory patients in clinical trials11 Opportunity for S.C. self-administer autoinjector US CIDP Market Opportunity 1. Komodo claims data 2013-2025, adjusted to account for 70% capture of real-world patient counts for biologic treated patients, adjusted to account for 27% misdiagnosed; 2. Other Tx: PLEX/Splenectomy/Thymectomy, Rituximab, Biologic; 3. Argenx Vyvgart Hytrulo HCP website; 4. Fierce Pharma, CIDP Pricing; 5. Argenx 4Q 2025 Financial Results, Feb 26, 2026; 6. Immunoglobulin – Global Market Analysis, Fortune Business Insights; 7. Mair D, et al. Novel therapies in CIDP. Journal of Neurology, Neurosurgery & Psychiatry 2025;96:38-46.; 8. Gogia B, et al. Chronic Inflammatory Demyelinating Polyradiculoneuropathy, StatPearls Publishing.; 9. Bus, S.R.M., et al. Clinical outcome of CIDP one year after start of treatment. J Neurol.; 10. Levine T, et al. Early deterioration of CIDP following transition from IVIg to FcRn inhibitor, Journal of the Neurological Sciences; 11. Novel therapies in CIDP, Journal of Neurology, Neurosurgery, and Psychiatry (2024). Claseprubart target profile Est. >$1B4,5 FcRn >2,000 pts3 I.V., S.C., Oral QW S.C. PFS Rapid [<10s] Q2W S.C. Autoinjector CIDP Patients1 Opportunity to ReachMore Patients Ig ~19,000 pts Steroids, ISTs, other2 ~10,000 pts Standard of care1 ~40,000 (~5% CAGR) + Steroids (~6,000 pts)

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![Slide 17](dnth-ex99_3s17.jpg)

Survey of US Neurologists supports potential transformative opportunity in CIDP of Neurologists strongly prefer treatment options without a boxed warning or REMS program ~54% Total Neurologists 80 Neuromuscular Specialist 81% Generalist 19% Academic 58% Community based 42% Sample Demographics ~13 years in active clinical practice (post-residency),on average ~90% of professional time spent providing direct patient care, on average ~60 CIDP patients seen in the past 12 months, on average of Neurologists strongly believe patients prefer treatments with more consistent and sustained symptom control ~79% of Neurologists strongly believe there is high unmet need for therapies with greater efficacy ~66% Dianthus 2026 Neurologist CIDP and MMN quantitative survey (n=80, N = 65 Neuromuscular specialists, N = 15 General Neurologists), fielded Q1 Data represents % of Neurologists selecting 7-9 on a 9-pt. agreement scale of Neurologists strongly believe patients prefer therapies that are more convenient and easier to administer ~75% Claseprubart aims to differentiate and effectively address the significant unmet needs in the CIDP market

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% of Surveyed Neurologists Who Strongly Believe… Surveyed Neurologists want safer, more effective and convenient treatment options than IVIg for CIDP patients Significant unmet need for effective therapies for patients who don't respond to IVIg 75% IVIg imposes a high treatment burden due to frequent and time-consuming infusions 59% IVIg boxed warning is concerning due to potential risk of kidney failure or thrombosis 55% Overall, surveyed Neurologists believe ~50% patients on IVIg have partial or no response to treatment Dianthus 2026 Neurologist CIDP and MMN quantitative survey (n=80, N = 65 Neuromuscular specialists, N = 15 General Neurologists), fielded Q1 Data represents % of Neurologists selecting 7-9 on a 9-pt. agreement scale Patients on IVIg commonly report waning efficacy prior to their next dose 56%

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Achieving this target profile could position claseprubart as a potential blockbuster treatment for CIDP Improvement over SoC (i.e. Ig) with continuous, effective symptom control C1s SAFETY (Enjaymo) EFFICACY (IVIg/SCIg) AUTOINJECTOR CONVENIENCE (DUPIXENT) Comparable safety to FDA-approved C1s & Classical Pathway inhibitor, leaving the lectin and alternative pathways intact Most convenient therapy with self-administered SHL-Molly autoinjector Claseprubart is an investigational agent that is not approved as a therapy in any indication in any jurisdiction worldwide. Safety and efficacy for claseprubart has not been evaluated in head-to-head comparative clinical studies. Autoinjector for claseprubart administration is anticipated to be SHL Medical's Molly technology, patented or patent pending in the US, China, India, Japan, Korea, Taiwan and at the European Patent Office Targeting Best-in-Class or Best-in-Disease Efficacy Targeting no Boxed Warning & REMS Targeting single 300mg/2mL S.C. Q2W

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Claseprubart has opportunity to compete as a potential 1L biologic in three large and growing US neuromuscular markets >100K patients >140K patients >150K patients AChR+ gMG patients Positive Ph. 2 data reported Sept. '25 >40K CIDP patients Early GO decision announced Mar. '26 Ph. 2 top-line data expected in 2H'26 Potential for US growth as only <20% of AChR+ patients treated with biologics >10K MMN patients Potential for aC1s inhibition to transform treatment landscape POC supporting classical pathway inhibition and limited competition Figures represent U.S. estimated patients only. gMG: >100,000 gMG U.S. patients from Komodo claims data accessed 2013-2025; approx. 85% of gMG patients have AChR autoantibody-driven disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7033452/# CIDP & MMN: Komodo claims data 2013-2025, adjusted to account for 70% capture of real-world patient counts for biologic treated patients; CIDP adjusted to account for 27% misdiagnosed Claseprubart has potential to capture meaningful market share across three synergistic multi-billion dollar markets  

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Advancing a leading autoimmune-focused biotech with two clinical stage programs Program Indication Ph. 1 Ph. 2 Ph. 3 Upcoming Milestones Claseprubart aC1s gMG >100,000 U.S. Patients Initiation of Ph. 3 study expected in mid-26 Ph. 3 top-line results expected in 2H'28 CIDP >40,000 U.S. Patients Part B top-line guidance expected by YE'26 Peer Milestone: riliprubart Ph. 3 MOBILIZE and VITALIZE (H2H vs. IVIg) data expected in 20273 MMN >10,000 U.S. Patients Ph. 2 top-line results expected in 2H'26 Peer Milestone: empasiprubart Ph. 3 data expected in Q4'264 DNTH212 BDCA2 and BAFF/APRIL Multiple Autoimmune Diseases Update on indication prioritization expected in 1H'26 Ph. 1 HV top-line results expected in 2H'26 Healthy volunteers (Part A) SLE patients (Part B) Strong balance sheet with ~$514M1 of cash & runway into 2028 ~46.4M shares outstanding2 Includes cash, cash equivalents and investments as of December 31, 2025 Shares outstanding on a pro forma basis as of March 4, 2026, which assumes the exercise of all outstanding pre-funded warrants Based on Sanofi Q4'25 financial results presentation Based on publicly available information: https://argenx.com/news/2026/press-release-3216531

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Q&AEarly GO Decision in CAPTIVATE CIDP Trial March 9, 2026