Groowe Groowe BETA / Newsroom
⏱ News is delayed by 15 minutes. Sign in for real-time access. Sign in

Form 8-K

sec.gov

8-K — Jade Biosciences, Inc.

Accession: 0001193125-26-408287

Filed: 2026-09-30

Period: 2026-09-30

CIK: 0001798749

SIC: 2834 (PHARMACEUTICAL PREPARATIONS)

Item: Other Events

Documents

8-K — d936098d8k.htm (Primary)

XML — IDEA: XBRL DOCUMENT (R1.htm)

8-K

8-K (Primary)

Filename: d936098d8k.htm · Sequence: 1

8-K

NASDAQ false 0001798749 0001798749 2026-09-30 2026-09-30

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): September 30, 2026

Jade Biosciences, Inc.

(Exact name of Registrant as specified in its charter)

Nevada

001-40544

83-1377888

(State or other jurisdiction

of incorporation)

(Commission

File Number)

(IRS Employer

Identification No.)

221 Crescent St., Building 23

Suite 105

Waltham, MA

02453

(Address of principal executive offices)

(Zip Code)

Registrant’s telephone number, including area code: (781) 312-3013

N/A

(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:

☐

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:

Title of each class

Trading

Symbol(s)

Name of each exchange

on which registered

Common Stock, $0.0001 par value per share

JBIO

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. ☒

Item 8.01.

Other Events.

On September 30, 2026, Jade Biosciences, Inc. (“Jade”) announced preclinical data characterizing JADE301, its anti-interferon beta (“IFN-ß”) monoclonal antibody in development for dermatomyositis (“DM”), a rare, chronic and debilitating autoimmune disease characterized by painful inflammatory skin disease and progressive muscle weakness. JADE301 is a fully human IgG1 monoclonal antibody with a YTE modification designed to selectively and potently neutralize IFN-ß and inhibit downstream signaling implicated as a proximal driver in DM pathogenesis.

Summary of JADE301 Preclinical Data

High-affinity, selective and potent IFN-ß neutralization

•

JADE301 demonstrated high-affinity binding to IFN-ß, with a KD of 11.3 pM, approximately 2.5-fold higher affinity than a dazukibart comparator, and no detectable binding to other interferon family proteins.

•

JADE301 potently inhibited downstream IFN-ß signaling.

o

In a human immune cell line, JADE301 inhibited induction of pSTAT with an IC50 of 13 pM, approximately 2.5-fold more potent than the dazukibart comparator.

o

Suppression of MX-1, a marker of IFN pathway activity relevant to DM, was demonstrated in human dermal fibroblasts, a disease-relevant skin cell type, and peripheral blood mononuclear cells; in human dermal fibroblasts, JADE301 inhibited MX-1 induction with an IC50 of 11 pM, approximately 8-fold more potent than the dazukibart comparator.

Differentiated pharmacokinetic profile supports potential for infrequent subcutaneous dosing

•

JADE301 demonstrated an approximately 30-day half-life following a 30 mg/kg intravenous dose in non-human primates (“NHPs”), approximately 3-fold longer than the dazukibart comparator.

•

Following subcutaneous (“SC”) administration in NHPs, JADE301 demonstrated an approximately 25-day half-life. Translational modeling predicted human SC bioavailability of approximately 73%–75%, compared with a reported dazukibart SC bioavailability in humans of approximately 43%–44%, supporting the potential for convenient, infrequent SC dosing.

•

JADE301 concentrations in muscle were consistent with the typical range reported for monoclonal antibodies, approximately 1%–4% of serum concentrations, providing a translational framework to inform dose selection and exposure at a key site of active disease in DM.

Favorable nonclinical tolerability profile

•

In a GLP toxicology study in NHPs, subcutaneous JADE301 was administered every two weeks at doses of 0, 50, 100 and 200 mg/kg and was well tolerated at all dose levels evaluated.

•

There were no treatment-related adverse clinical observations or meaningful adverse findings on laboratory or other standard safety assessments. No treatment-related histopathology findings were observed.

JADE301 Phase 1 Development

Jade expects to initiate a placebo-controlled, single ascending-dose Phase 1 trial evaluating subcutaneous JADE301 in 24 healthy volunteers in the fourth quarter of 2026, with interim data anticipated in the second half of 2027. The study is designed to assess safety and tolerability, and to characterize the pharmacokinetic and immunogenicity profile of JADE301.

Forward-Looking Statements

Certain statements in this communication, 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 Private Securities Litigation Reform Act of 1995. These forward-looking statements include, but are not limited to, express or implied statements relating to Jade’s expectations, hopes, beliefs, intentions or strategies regarding the future of its pipeline and business including, without limitation: Jade’s ability to achieve the expected benefits or opportunities with respect to JADE301; the expected timelines for the initiation of, and the availability of interim data from, the Phase 1 clinical trial of JADE301; the projected human bioavailability of JADE301; and the potential therapeutic uses, efficacy, durability, safety profiles, and dosing of JADE301. The words “opportunity,”

“potential,” “milestones,” “pipeline,” “can,” “goal,” “strategy,” “target,” “anticipate,” “achieve,” “believe,” “contemplate,” “continue,” “could,” “estimate,” “expect,” “intends,” “may,” “plan,” “possible,” “project,” “should,” “will,” “would” and similar expressions (including the negatives of these terms or variations of them) may identify forward-looking statements, but the absence of these words does not mean that a statement is not forward-looking. These forward-looking statements are based on current expectations and beliefs concerning future developments and their potential effects. There can be no assurance that future developments affecting Jade will be those that have been anticipated. These forward-looking statements involve a number of risks, uncertainties (some of which are beyond Jade’s control) or other assumptions that may cause actual results or performance to be materially different from those expressed or implied by these forward-looking statements. These risks and uncertainties include, but are not limited to: the planned clinical trial of JADE301 and any other clinical trials may be delayed or may not demonstrate desirable efficacy or predicted performance; adverse events and safety signals may occur; modeled and predicted data may not be realized in actual clinical studies; Jade may experience unanticipated costs, difficulties or delays in the product development process; Jade’s product candidates may be delayed to a point where they are not commercially viable; clinical trial start up, enrollment or regulatory challenges may occur; challenges associated with Jade’s dependence on third-party vendors for the development, manufacture and supply of its product candidates may occur; and the other risks, uncertainties and factors more fully described in Jade’s most recent filings with the Securities and Exchange Commission (including the Quarterly Report on Form 10-Q for the quarter ended June 30, 2026). Should one or more of these risks or uncertainties materialize, or should any of Jade’s assumptions prove incorrect, actual results may vary in material respects from those projected in these forward-looking statements. You should not place undue reliance on forward-looking statements in this communication, which speak only as of the date they are made and are qualified in their entirety by reference to the cautionary statements herein. Jade does not undertake or accept any duty to release publicly any updates or revisions to any forward-looking statements, except as required by law. This communication does not purport to summarize all of the conditions, risks and other attributes of an investment in Jade.

SIGNATURES

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

Jade Biosciences, Inc.

(Registrant)

Date: September 30, 2026

By:

/s/ Bradford Dahms

Name:

Bradford Dahms

Title:

Chief Financial Officer

XML — IDEA: XBRL DOCUMENT

XML

Filename: R1.htm · Sequence: 6

v3.26.3

Document and Entity Information

Sep. 30, 2026

Cover [Abstract]

Security Exchange Name

NASDAQ

Amendment Flag

false

Entity Central Index Key

0001798749

Document Type

8-K

Document Period End Date

Sep. 30, 2026

Entity Registrant Name

Jade Biosciences, Inc.

Entity Incorporation State Country Code

NV

Entity File Number

001-40544

Entity Tax Identification Number

83-1377888

Entity Address, Address Line One

221 Crescent St.

Entity Address, Address Line Two

Building 23

Entity Address, Address Line Three

Suite 105

Entity Address, City or Town

Waltham

Entity Address, State or Province

MA

Entity Address, Postal Zip Code

02453

City Area Code

(781)

Local Phone Number

312-3013

Written Communications

false

Soliciting Material

false

Pre Commencement Tender Offer

false

Pre Commencement Issuer Tender Offer

false

Security 12b Title

Common Stock, $0.0001 par value per share

Trading Symbol

JBIO

Entity Emerging Growth Company

true

Entity Ex Transition Period

true

X

- Definition

Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

+ References

No definition available.

+ Details

Name:

dei_AmendmentFlag

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Area code of city

+ References

No definition available.

+ Details

Name:

dei_CityAreaCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Cover page.

+ References

No definition available.

+ Details

Name:

dei_CoverAbstract

Namespace Prefix:

dei_

Data Type:

xbrli:stringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

+ References

No definition available.

+ Details

Name:

dei_DocumentPeriodEndDate

Namespace Prefix:

dei_

Data Type:

xbrli:dateItemType

Balance Type:

na

Period Type:

duration

X

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

dei_

Data Type:

dei:submissionTypeItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Address Line 2 such as Street or Suite number

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine2

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Address Line 3 such as an Office Park

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine3

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Name of the City or Town

+ References

No definition available.

+ Details

Name:

dei_EntityAddressCityOrTown

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Code for the postal or zip code

+ References

No definition available.

+ Details

Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Name of the state or province.

+ References

No definition available.

+ Details

Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

dei_

Data Type:

dei:stateOrProvinceItemType

Balance Type:

na

Period Type:

duration

X

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityCentralIndexKey

Namespace Prefix:

dei_

Data Type:

dei:centralIndexKeyItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Indicate if an emerging growth company has elected not to use the extended transition period for complying with any new or revised financial accounting standards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 7A

-Section B

-Subsection 2

+ Details

Name:

dei_EntityExTransitionPeriod

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

dei_

Data Type:

dei:edgarStateCountryItemType

Balance Type:

na

Period Type:

duration

X

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityRegistrantName

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

dei_

Data Type:

dei:employerIdItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Local phone number for entity.

+ References

No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

+ Details

Name:

dei_PreCommencementIssuerTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

+ Details

Name:

dei_PreCommencementTenderOffer

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

+ Details

Name:

dei_Security12bTitle

Namespace Prefix:

dei_

Data Type:

dei:securityTitleItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

dei_

Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

dei_

Data Type:

dei:tradingSymbolItemType

Balance Type:

na

Period Type:

duration

X

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

+ Details

Name:

dei_WrittenCommunications

Namespace Prefix:

dei_

Data Type:

xbrli:booleanItemType

Balance Type:

na

Period Type:

duration