# EDGAR Filing Document

**Accession Number:** 0001953926
**File Stem:** 0001104659-25-056215
**Filing Date:** 2025-6
**Character Count:** 32923
**Document Hash:** ced08721216e9af05ecd49afe0303aa5
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-25-056215.hdr.sgml**: 20250604

**ACCESSION NUMBER**: 0001104659-25-056215

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 38

**CONFORMED PERIOD OF REPORT**: 20250604

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20250604

**DATE AS OF CHANGE**: 20250604

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Zenas BioPharma, Inc.
- **CENTRAL INDEX KEY:** 0001953926
- **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:** 001-42270
- **FILM NUMBER:** 251021866

**BUSINESS ADDRESS:**
- **STREET 1:** 852 WINTER STREET, SUITE 250
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451
- **BUSINESS PHONE:** 857-271-2954

**MAIL ADDRESS:**
- **STREET 1:** 852 WINTER STREET, SUITE 250
- **CITY:** WALTHAM
- **STATE:** MA
- **ZIP:** 02451

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Zenas BioPharma (Cayman) Ltd
- **DATE OF NAME CHANGE:** 20221108

?xml version='1.0' encoding='ASCII'?

**UNITED STATES**

**SECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 8-K**

**CURRENT REPORT**

**Pursuant to Section 13 or 15(d)**

**of the Securities Exchange Act of 1934**

**Date of Report (Date of earliest event reported): June 4, 2025**

**ZENAS BIOPHARMA, INC.**

**(Exact name of registrant as specified in its charter)**

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| | | |
|:---|:---|:---|
| **Delaware** | **001-42270** | **93-2749244** |
| **(State or other jurisdiction**<br> **of incorporation)** | **(Commission**<br> **File Number)** | **(IRS Employer**<br> **Identification No.)** |
| **852 Winter Street, Suite 250**<br> **Waltham, MA** | **852 Winter Street, Suite 250**<br> **Waltham, MA** | **02451** |
| **(Address of principal executive offices)** | **(Address of principal executive offices)** | **(Zip Code)** |

---

**(Registrant's telephone number, including area code): (857) 271-2954**

**Not Applicable**

**(Former name or former address, if changed since last report)** 

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 (see General Instruction A.2. below):

◻ 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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| | | |
|:---|:---|:---|
| **Title of each class** | **Trading**<br> **Symbol(s)** | **Name of each exchange**<br> **on which registered** |
| **Common Stock, par value $0.0001 per share** | **ZBIO** | **The Nasdaq Global Select 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. ◻

**Item 7.01** **Regulation FD Disclosure.** 

Zenas BioPharma, Inc. (the "Company") is furnishing as Exhibit 99.1 to this Current Report on Form 8-K an investor presentation (the "Investor Presentation") which may be used, in whole or in part, and subject to modification, at management's presentation at the Jefferies Global Healthcare Conference on June 5, 2025, at meetings with investors and analysts at such conference on June 4-5, 2025, and at subsequent meetings with investors and analysts.

The information in this Item 7.01 (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 in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such filing.

 ****

***Cautionary Note Regarding Forward-Looking Statements.*** The Investor Presentation contains forward-looking statements that involve certain risks and uncertainties that could cause actual results to differ materially from those expressed or implied by these statements. Please refer to the cautionary notes in the Investor Presentation regarding these forward-looking statements.

**Item 9.01** **Financial Statements and Exhibits.** 

(d) Exhibits

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| | |
|:---|:---|
| **Exhibit<br> No.** | **Description** |
| [99.1](tm2517068d1_ex99-1.htm) | [Investor Presentation, dated June 4, 2025](tm2517068d1_ex99-1.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.

---

| | |
|:---|:---|
| **ZENAS BIOPHARMA, INC.** | **ZENAS BIOPHARMA, INC.** |
| By: | /s/ Jennifer Fox |
|  | Name: Jennifer Fox |
|  | Title: Chief Business Officer and Chief Financial Officer |

---

Date: June 4, 2025

## Exhibit 99.1

**Exhibit 99.1**

![](tm2517068d1_ex99-1img001.jpg)

1 Zenas BioPharma Corporate Presentation June 2025 Enabling patients with autoimmune diseases to reimagine life

![](tm2517068d1_ex99-1img002.jpg)

2 Disclaimer FORWARD - LOOKING STATEMENTS: This presentation contains "forward - looking statements" which involve risks, uncertainties and contingencies, many of which are beyond the control of the Company, which may cause actual results, performance, or achievements to differ materially from anticipated results, performance, or achievements. All statements other than statements of historical facts contained in this presentation are forward - looking statements. In some cases, you can identify forward - looking statements by terms such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "contemplate," "believe," "estimate," "predict," "potential" or "continue" or the negative of these terms or other similar expressions, although not all forward - looking statements contain these words. Forward - looking statements include statements concerning Zenas's plans, objectives, expectations and intentions; its future financial or business performance; the timing and results of ongoing and future clinical trials and potential regulatory approval and commercialization; its ability to identify strategic partners for its pipeline programs; the potential commercial opportunities for its product cand ida tes; the potential competition for its product candidates; the potential commercial attributes for its product candidates; the Company's cash guidance. The forward - loo king statements in this presentation speak only as of the date of this presentation and are subject to a number of known and unknown risks, uncertainties and assumptions that coul d c ause the Company's actual results to differ materially from those anticipated in the forward - looking statements, including, but not limited to: the Company's limited operating history , incurrence of substantial losses since the Company's inception and anticipation of incurring substantial and increasing losses for the foreseeable future; and the Company's need for substantial additional financing to achieve the Company's goals; the uncertainty of clinical development, which is lengthy and expensive, and characterized by uncertain outc ome s, and risks related to additional costs or delays in completing, or failing to complete, the development and commercialization of the Company's current product candidates or any fut ure product candidates; delays or difficulties in the enrollment and dosing of patients in clinical trials; the impact of any significant adverse events or undesirable side effect s c aused by the Company's product candidates; potential competition, including from large and specialty pharmaceutical and biotechnology companies, many of which already have approv ed therapies in the Company's current indications; the Company's ability to realize the benefits of the Company's current or future collaborations or licensing arrangements and ab ility to successfully consummate future partnerships; the Company's ability to obtain regulatory approval to commercialize any product candidate in the United States or any other juri sdi ction, and the risk that any such approval may be for a more narrow indication than the Company seeks; and other risks and uncertainties described in the section "Risk Factors" in t he Company's Quarterly Report for the three months ended March 31, 2025, and subsequent reports filed with the SEC. The forward - looking statements in this presentation are inherently un certain and are not guarantees of future events. Because forward - looking statements are inherently subject to risks and uncertainties , some of which cannot be predicted or quantified and some of which are beyond the Company's control, you should not unduly rely on these forward - looking statements. The events and circumstances reflected in the forward - looking statements may not be achieved or occur and actual future results, levels of activity, performance and events and circumstances could differ materially from those projected in the forward - looking statements. Moreover, the Company operates in an evolving environment. New risks and uncertainties may emerge from time to time, and management cannot predict all risks and uncertainties. Except as required by applicable law, the Company does not undertake to publicly update or revise any forward - looking statements contained herein, whether as a result of any new information, future events, changed circumstances or otherwise. MARKET AND INDUSTRY DATA: Unless otherwise indicated, market and industry data contained in this presentation, including potential commercial opportuni tie s, is based on the Company's management's estimates and research, as well as industry and general publications and research and studies conducte d b y third parties. Although the Company believes that the information from these third - party publications, research and studies included in this presentation is reliable, the Co mpany has not independently verified the accuracy or completeness of this information. Management's estimates are derived from publicly available information, their knowledge of the Company's industry and their assumptions based on such information and knowledge, which the Company believes to be reasonable. This data involves a number of assumptions and l imi tations and the industry in which the Company operates is subject to a high degree of uncertainty and risk due to a variety of factors. TRADEMARKS: This presentation may include references to the Company's trademarks and trademarks belonging to other entities. The Zenas Bi oPh arma word mark, logo mark, and the "lightning bolt" design are trademarks of Zenas BioPharma, Inc. or its affiliated companies. Solely for convenience, some of the trademarks and trade names referred to in this presentation, including logos, artwork and other visual displays, may be listed without the® or symbols, but such references are not intended to indicate in any way that Zenas will not assert, to the fullest extent under applicable law, Zenas's rights or the rights of the applicable licensor to these trademar ks and trade names.

![](tm2517068d1_ex99-1img003.jpg)

3 Potentially highly differentiated I&I franchise molecule Obexelimab is the first bifunctional B cell targeting (CD19 x Fc γ RIIb) antibody in a Phase 3 trial (IgG4 - Related Disease), and randomized Phase 2 trials (RMS and SLE), which represent a potential multi - billion - dollar commercial opportunit y 1 Well - funded into Q4:26 through meaningful Phase 3 and Phase 2 readouts Q1 2025 cash of approximately $314M 2 Zenas: Creating a global, immunology - based development and commercial biotechnology company Enabling patients with autoimmune diseases to reimagine life 1 Company estimate based on disease prevalence and pricing of advanced therapies within indication 2 Q4:26 cash guidance is based on Company's expectation Global capabilities and experienced Team Established global development and regulatory capabilities led by a team with a history of successful product approvals and commercial launches

![](tm2517068d1_ex99-1img004.jpg)

4 Obexelimab: Multiple upcoming Phase 2 and Phase 3 data readouts 1 Zenas acquired exclusive worldwide rights to obexelimab from Xencor, Inc. 2 Bristol Myers Squibb & Co. holds exclusive development and commercialization rights in JPN, SK, TWN, HK, SGP, AUS 3 Randomized versus placebo Next Milestone Trial/Status Indication Program Expected around year end 2025 Phase 3 Topline Results Phase 3 INDIGO trial enrolled 2,3 IgG4 - RD (Immunoglobulin G4 - Related Disease) Obexelimab 1 CD19 x Fc ƴ RIIb Bifunctional mAb Expected early Q4 2025 Primary endpoint (12 - week) data Phase 2 MoonStone trial enrolling 3 RMS (Relapsing Multiple Sclerosis) Expected mid - 2026 Primary endpoint (24 - week) data Phase 2 SunStone trial enrolling 3 SLE (Systemic Lupus Erythematosus)

![](tm2517068d1_ex99-1img005.jpg)

5 Obexelimab: A potentially differentiated B cell targeted therapy 1 Chu et al . Molecular Immunology 2008 & Zenas data on file 2 Szili et al . mAbs 2014 3 Chu et al . Journal of Translational Autoimmunity 2021 4 Chu et al. Arthritis & Rheumatology 2014 Source: Zenas BioPharma • Fc γ RIIb mimics natural antigen - antibody complex for potent inhibition of B cells • Obexelimab binding affinity for human FcγRIIb increased approximately 230 - fold relative to human native IgG1 due to Fc engineering 2 • Engineered to avoid ADCC / CDC - mediated depletion ; non - reliance upon the presence of immune effector cells • Impacts antibody production, proliferation, cytokine secretion, and antigen presentation to T cells • Continuous exposure results in inhibitory activity within tissue Obexelimab co - engagement of CD19 and Fc γ RIIb results in an inhibitory effect , rather than direct depletion 1,2,3,4

![](tm2517068d1_ex99-1img006.jpg)

6 Obexelimab demonstrated clinical activity in multiple, completed clinical trials SAD = Single Ascending Dose, HV = Healthy Volunteers, PK = Pharmacokinetics, MAD = Multiple Ascending Dose 1 Wang, X. American College of Rheumatology 2022 poster presentation 2 Wang, X. American College of Rheumatology 2023 poster presentation 3 Jaraczewska - Baumann et al EULAR 2015 poster presentation (obexelimab efficacy at all dose levels) 4 Perugino, C . et al . Nature Reviews Rheumatology . 16, 702 – 714 (2020) 5 Merrill, J. et al . Arthritis and Rheumatology . Vol. 75, 2185 - 2194 (2023) 6 Wang, X. Japan College of Rheumatology 2023 oral presentation Outcome Description Trial Stage • Demonstrated proof - of - mechanism SAD HV, safety and PK Phase 1 1 • Proof - of - mechanism and clinical activity established • Day 85 (all dose levels): ACR20: 78%, ACR50: 33%, ACR70: 14% 3 MAD Rheumatoid Arthritis (RA) Phase 1b/2a 2 • Clinical activity established; rapid disease response (mean of 21 days), and sustained response achieved in 93% of patients Pilot Study IgG4 - Related Disease Phase 2 4 • Clinical activity established • Primary endpoint effect size of 17% for ITT population; 35% effect size for population with optimal exposure level (C trough) • Biomarkers potentially predictive of obexelimab response identified Randomized Controlled Systemic Lupus Erythematosus (SLE) Phase 2 5 • Established subcutaneous formulation with improved tolerability, and potential for optimized drug exposure (C trough) Bioequivalence HV, Subcutaneous (SC) versus Intravenous (IV) dosing Phase 1 6

![](tm2517068d1_ex99-1img007.jpg)

7 • Scientific merit examples: Role of B cells in disease pathogenesis, prior preclinical or clinical data supporting activity of B cell therapies • Regulatory merit examples: Ease/clarity of regulatory path, validated endpoints, trial size and duration etc. • Commercial merit examples: Level of unmet need, epidemiology, competition, pricing etc. Development strategy: fast - to - market orphan indication followed by expansion into additional autoimmune diseases >40 indications initially considered for development Assessed based on scientific , regulatory , and commercial merit 6 indications selected for detailed evaluation; first 3 prioritized for clinical development; Multiple indications ongoing assessment IgG4 - RD RMS SLE Others ongoing Obexelimab indication strategy encapsulated a "total business view" including scientific, clinical/regulatory and commercial assessments

![](tm2517068d1_ex99-1img008.jpg)

8 Obexelimab: IgG4 - RD

![](tm2517068d1_ex99-1img009.jpg)

9 Disease Overview: • Presents with single or multi - organ involvement • A s disease progresses patients experience new or worsening symptoms (e.g., flare) • E arly inflammatory disease state moves to a fibrotic stage, which can lead to major irreversible tissue damage and organ failure Pathophysiology: • Expansion of CD19+ and IgG4+ B cells and plasmablasts with tissue infiltration • These cells produce IgG4 and inflammatory cytokines, and activate T cells through antigen presentation exacerbating inflammation & fibrosis Patient Population: • We estimate the prevalence of IgG4 - RD patients in the U.S. is approximately 20,000 to 40,000, and approximately 20,000 to 40,000 collectively in the UK, Germany, France, Italy, and Spain alone 2 Frequent Occasional Infrequent KIDNEY FOCAL MASSES BILE DUCT STRICTURES LUNG MASSES AND NODULES, BRONCHIAL WALL THICKENING THYROID GLAND ENLARGEMENT LACRIMAL ENLARGEMENT PACHYMENINGES DIFFUSE THICKENING ORBITAL MASSES, EXTRA - OCULAR MUSCLE MYOSITIS MAJOR SALIVARY GLAND ENLARGEMENT PANCREAS ENLARGEMENT, DIABETES, EXOCRINE INSUFFICIENCY SOFT TISSUE MASS ENCASING THE ANTEROLATERAL AORTA AORTA WALL THICKENING 1 Perugino, C. et al. Nature Reviews Rheumatology . 16, 702 – 714 (2020); Zhang, W & Stone, J. Lancet Rheumatology . 1(1), E55 - E65 (2019); Mattoo et al J Allergy Clin Immunol . 2014; UpToDate 2 Wallace et al 2023 and Zenas BioPharma research IgG4 - RD: A debilitating chronic fibro - inflammatory disease affecting multiple organ systems 1

![](tm2517068d1_ex99-1img010.jpg)

10 Patients with IgG4 - RD will likely experience continued flares despite first - line treatment 1 Perugino, C. et al. Nature Reviews Rheumatology . 16, 702 – 714 (2020) 2 As measured by secondary endpoints in ongoing Phase 3 INDIGO trial Repeated disease flares can damage new or existing disease sites 1 Subclinical inflammatory processes left untreated can lead to fibrosis and irreversible organ damage 1 Obexelima b once - weekly, self - administered, subcutaneous injection could potentially address the underlying disease burden 2 = Flare Underlying disease burden Disease course over time ACR/EULAR threshold of 20 points for classification of IgG4 - RD

![](tm2517068d1_ex99-1img011.jpg)

11 • Induction and Maintenance • 100% of patients who completed trial met primary endpoint 2 • No flares or steroid use after Day 57 • 93% with ongoing response at end of trial • 80% with prior rituximab achieved complete remission • Well tolerated; most frequent AEs were IV infusion - related gastrointestinal events; three SAEs were not considered to be related to obexelimab Obexelimab: Phase 2 IgG4 - RD results demonstrated rapid, robust, and sustained reduction in IgG4 - RD disease activity 1 Rapid and sustained IgG4 - RD RI response 0 5 10 15 20 25 30 1 15 29 57 85 113 141 169 197 Completed Early termination obexelimab 5mg/kg IV Q2W x 12 doses (N=15) IgG4 - RD RI Day 1 Perugino et al. Lancet Rheumatology 2023. Open - label, single - arm Phase 2 PoC trial in 15 obexelimab - treated patients with moderate to severe disease as induction and main tenance, one or more organ systems involved and an IgG4 - RD Responder Index (RI) of ≥ 3 2 Primary endpoint: proportion of patients on Day 169 with a decrease in IgG4 - RD RI > 2 points

![](tm2517068d1_ex99-1img012.jpg)

12 Phase 2 IgG4 - RD trial: Obexelimab induced rapid remission of active flares and maintained durable responses Source: Perugino CA et al. Lancet Rheumatol . 2023; Carruthers MN et al. Ann Rheum Dis . 2015 Note: No comparative head - to - head trials were conducted GC=glucocorticoid; RI=responder index Rituximab (1000 mg q15d x 2) Obexelimab (5mg/kg q14d x 12) Phase 2 single - arm, open label (n=30) Phase 2 single - arm, open label (n=15) Design RI score (11.0) Number of organs involved (3.5) RI score (12.0) Number of organs involved (4.0) Baseline characteristics 23/30 (77%) 12/15 (80%) Primary endpoint: decline of IgG4 - RD RI > 2 points, no flares before month six, no GCs between two to six months 3/30 (10%) 0 GC use through 6 months (after tapering) 22/30 (73%): Improvement of IgG4 - RD RI > 2 points for 6 months 13/14 (93%) responders had ongoing response at month 6 Sustained disease response 43 21 Mean time to disease response (days) 3/30 (10%) 1/15 (6.7%) Relapse within 6 months

![](tm2517068d1_ex99-1img013.jpg)

13 1 Stone, DH et al. Inebilizumab for Treatment of IgG4 - Related Disease. NEJM , November, 2024. MoA = mechanism of action; RoA = route of administration; RCP = Randomized controlled period INDIGO and MITIGATE trial designs substantially similar MITIGATE 1 (Uplizna®) INDIGO (obexelimab) B cell depletor B cell inhibitor MoA 300 mg IV on Day 1& Day 15 Q6M 250 mg SC weekly PFS / auto - injector RoA and frequency, dose 22 20 Number of countries 80 ~100 Number of sites RCP 52 weeks; plus OLE RCP 52 weeks; plus OLE Trial design 135 ~190 Number of patients Time to first flare (Adjudicated/Investigator) Time to first flare (Adjudicated/Investigator) Primary endpoint 87% reduction in IgG4 - RD flare risk at 52 - weeks compared to placebo (HR = 0.13, p < 0.001) Expected around year - end 2025 Results 90% flare free at week 52 59% in flare - free, treatment - free , steroid - free complete remission at week 52, 37% at week 26

![](tm2517068d1_ex99-1img014.jpg)

14 INDIGO Trial Summary: • Design: Randomized, double - blind, placebo controlled • Treatment: weekly obexelimab 250 mg subcutaneous or placebo control; GC taper to 0 mg by week 8 • Primary endpoint: Time to disease flare through week 52 • Secondary endpoints include: 52 - week flare rate, Achievement of complete remission, Use and quantity of rescue medication, Change in GC - associated toxicity as measured by the Glucocorticoid Toxicity Index (GTI) Phase 3 INDIGO IgG4 - RD trial enrollment complete Trial of over 190 patients, the largest ever conducted, with topline results expected around year - end 2025 SCREENING • 20 - 60 mg GC Tx for flare • 20mg GC at trial entry Placebo Q1W for 52 weeks (n=~100) Open label extension 1:1 Obexelimab Q1W for 52 weeks (n=~100) GC taper to 0mg by week 8 GC taper to 0mg by week 8 1 Stone, et al. Inebilizumab for Treatment of IgG4 - Related Disease. NEJM . Nov 2024. GC = glucocorticoid 60% PBO rate for MITIGATE a derisking event for INDIGO assumptions 1

![](tm2517068d1_ex99-1img015.jpg)

15 Obexelimab represents a compelling $1billion+ commercial revenue opportunity in the U.S. alone Estimated U.S. prevalence: 30 - 40K Current U.S. diagnosed prevalence:~20K Treated with frontline Tx (steroids and non - steroidal immunosuppressants): ~20K Stable remission: ~8K - 10K Chronic disease ~10K - 12K x Diagnosed prevalence for IgG4 - RD expected to increase with introduction of first approved therapies x Attractive orphan pricing creates a market opportunity of ~$3 billion in the U.S. alone x Similar prevalence and potential for orphan pricing in Europe creates a similar multi - billion market opportunity in addition to the U.S. x Zenas team has extensive track record successfully building commercial organizations and launching drugs in the U.S. and Europe Currently diagnosed patients eligible for maintenance therapies = $3 billion U.S. market opportunity at orphan pricing

![](tm2517068d1_ex99-1img016.jpg)

16 Obexelimab: Multiple Sclerosis

![](tm2517068d1_ex99-1img017.jpg)

17 Phase 2 MoonStone RMS trial (n~110) Standard design with MRI measurements; highly predictive of successful outcome in large randomized trials SCREENING Active RMS (relapsing remitting MS or relapsing secondary progressive MS) : • EDSS <5.5 \* Open label extension 2:1 Randomization Obexelimab Q1W \* EDSS 5.5 = disability severe enough to preclude full daily activities. Able to walk without aid or rest for 100m Placebo Q1W Obexelimab Q1W Week 12 Primary endpoint: Number of new T1Gd - enhancing lesions Week 24 Additional endpoints: including disease progression endpoints Week 12 Week 24 MoonStone Trial Summary: • Design: Double - blind, randomized, placebo controlled with placebo crossover at week 12 • Treatment: obexelimab 250mg SC weekly vs. placebo control (through week 12) • Primary endpoint: Number of cumulative, new T1 Gd - enhancing lesions at week 12 • Includes 8 - and 12 - week lesions, (excludes week 4) • Secondary endpoints: Utilizing standardized assessments, imaging and biomarkers to evaluate impact on disease progression/silent progression

![](tm2517068d1_ex99-1img018.jpg)

18 Moonstone key inclusion/exclusion criteria are similar to those of previous Phase 2 B cell - directed programs Previous B cell - directed therapy global Phase II trials \* Obexelimab / MoonStone Phase II Key inclusion criteria • One or more relapses in the past year and/or two+ within the past two/three years +/ - 1 or more Gd+ lesions in prior 6 - 12 months • One relapse in past year OR ≥1 in past two years OR ≥1 Gd+ lesion in prior 6 months Disease Activity • EDSS of ≤ 5.5/6.0 at screening; for most trials, ≥ 10 years disease duration for patients with EDSS ≤ 2.0 • EDSS of ≤ 5.5 at screening; ≥ 10 years disease duration for patients with EDSS ≤ 2.0 Disability level • No prior use (early trials) OR ≥6 months washout / B cell recovery (whichever is longer) • No prior use Prior B cell treatment \* Including: ocrelizumab (anti - CD20), ofatumumab (anti - CD20), ublituximab (anti - CD20), tolebrutinib (BTKi), frexalimab (anti - CD40L), and fenebrutinib (BTKi) Phase 2 RMS trials for frexalimab and fenebrutinib reported 0.2 and 0.03 mean new Gd+ T1 lesions at week 12, respectively \* \* Data for intravenous frexalimab cohort (progressed to Phase 3); frexalimab and fenebrutinib are most recent global Phase 2 RM S trials to report week 12 data

![](tm2517068d1_ex99-1img019.jpg)

19 MoonStone data can potentially drive several Phase 3 development paths for obexelimab in multiple sclerosis 2027+ 2026 2025 Phase 3 RMS trial 1 Phase 3 RMS trial 2 MoonStone Phase 2 (RMS) Phase 3 nrSPMS trial Phase 3 PPMS trial With its CD19 targeting, non - depleting mechanism of action, convenient dosing, and the potential to impact both relapse - associated worsening and progression independent of relapse activity, obexelimab could offer a differentiated therapeutic option for patients with MS

![](tm2517068d1_ex99-1img020.jpg)

20 Obexelimab: Systemic Lupus Erythematosus

![](tm2517068d1_ex99-1img021.jpg)

21 Potential for improved clinical activity with an optimized obexelimab dosing regimen 17% 35% 52% 0% 10% 20% 30% 40% 50% 60% Intention - to - treat population 1 Optimized exposure population 2 Biomarker positive population 3 Patients at W32 without loss of improvement (∆" vs. PBO") Source: Merrill et al. Arthritis Rheumatol . 2023 1 Defined as all randomized patients receiving at least one dose of study medication 2 C trough Quartiles 3 & 4 in efficacy evaluable analysis 3 Biomarker positive defined as patients in predefined lupus phenotypic gene expression clusters 3 & 6 (~38% of evaluated popul ati on) Higher clinical activity observed with obexelimab in a Phase 2 trial with optimized exposure, and in biomarker positive population Screening Placebo IV Q2W for 32 weeks (n=52) 1:1 Obexelimab 5mg/kg IV Q2W for 32 weeks (n=52) • Current approved therapies demonstrate modest effect sizes of 12 – 17% over placebo on SRI - 4/BICLA assessments

![](tm2517068d1_ex99-1img022.jpg)

22 Primary Endpoint: Reduction of SLE disease activity at week 24 by BILAG - Based Composite Lupus Assessment (BICLA) Phase 2 SunStone SLE trial 1 enrolling Designed to confirm obexelimab activity in all - comer and biomarker populations SCREENING Active SLE: • BILAG ≥1A or ≥2B • SLEDAI ≥6 • PI confirmation Stable steroids Placebo Q1W for 24 weeks (n= 95) Follow - up 1:1 Obexelimab Q1W for 24 weeks (n= 95) GC taper to ≤5 mg by week 12 GC taper to ≤5 mg by week 12 1 Double - blind, randomized, placebo - controlled • SC dosing to improve PK (steady state C trough above Phase 2 top (4 th) quartile for all patients) • Powered on appropriate placebo response and effect size assumptions • Strict adjudication for eligibility and assessment (moderate/severe patients only); strict corticosteroid tapering rules to reduce placebo responses Incorporates learnings from previous Phase 2 trial to increase POS

![](tm2517068d1_ex99-1img023.jpg)

23 Obexelimab's differentiated profile potentially positions it to be a market - leading therapy for multiple I&I diseases Systemic Lupus Erythematosus (SLE) Multiple Sclerosis (RMS, PPMS) Immunoglobulin G4 Related Disease (IgG4 - RD) Indication ~150,000 patients (US) ~170,000 patients (EU) ~650,000 patients (US) ~670,000 patients (EU) ~20,000 - 40,000 patients (US) ~20,000 - 40,000 patients (EU) Market Size Tremendous need for new therapeutics that provide greater efficacy than currently approved agents in a >$8 billion market mAbs targeting B cells are well validated and represent the leading therapeutic category (>$9 billion). Self administered SC dosing and non - depleting mechanism highly desired Diagnosed patient population expected to increase with introduction of first approved therapies, validating targeting B cells via CD19 as a highly effective treatment Commercial Insights Obexelimab is well - positioned as a potential first - in - class B cell inhibitor across I&I indications Existing obexelimab clinical data indicate the potential for the current dosing regimen to provide differentiated clinical benefit in SLE Obexelimab has the potential to provide a front - line, convenient alternative to intermittently - dosed B cell "depletors" Currently 10,000+ patients could benefit from continuous therapy in the US alone, representing a ~$3 Billion US market Obexelimab Opportunity Obexelimab represents a potential multi - billion dollar franchise molecule across I&I indications

![](tm2517068d1_ex99-1img024.jpg)

24 Accomplished Executive Team Extensive experience developing and commercializing biopharmaceuticals Haley Laken, Ph.D. CSO Lonnie Moulder CEO & Chairman Joe Farmer President & COO Jennifer Fox CFO & CBO COLLECTIVELY, ZENAS MANAGEMENT HAS: • 70+ IND filings • 30+ BLA/NDA filings • 30+ Commercial product launches • Deep experience across numerous biotech and pharmaceutical companies Caroline Chevalier CHRO Orlando Oliveira CCO Jeff Held CLO Lisa von Moltke, M.D. Head of R&D & CMO

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25 Obexelimab, an I&I franchise molecule Obexelimab is a potentially differentiated B cell therapeutic in development for IgG4 - RD, RMS and SLE, each representing a potential multi - billion - dollar commercial opportunity 1 Multiple upcoming Phase 2 and Phase 3 data updates expected Obexelimab Phase 3 pivotal trial results expected for INDIGO (IgG4 - RD) around year - end 2025, Phase 2 results for MoonStone (RMS) early Q4 2025 and Sunstone (SLE) mid - 2026 Deeply experienced team Record of strong operational results: multiple clinical, regulatory and commercial successes Well - funded through results of ongoing obexelimab clinical trials Q1 2025 cash of approximately $314M; capitalized for clinical data readouts into Q4:26 Zenas: Creating a global, immunology - based development and commercial biotechnology company Enabling patients with autoimmune diseases to reimagine life 1 Company estimate based on disease prevalence and pricing of advanced therapies within indication 2 Q4:26 cash guidance is based on Company's expectation