Jade Biosciences to Host Conference Call and Webcast on June 1, 2026, at 8:00 a.m. ET to Discuss Interim Phase 1 Healthy Volunteer Results for JADE101, a Novel, Potentially Best-in-Class Anti-APRIL Monoclonal Antibody in Development for IgA Nephropathy

SAN FRANCISCO and VANCOUVER, British Columbia, May 29, 2026 (GLOBE NEWSWIRE) -- Jade Biosciences, Inc. (the “Company” or “Jade”) (Nasdaq: JBIO), a clinical-stage biotechnology company focused on developing best-in-class therapies for autoimmune diseases, today announced that it will host a conference call and webcast on Monday, June 1, 2026, at 8:00 a.m. ET to discuss results from the ongoing Phase 1 healthy volunteer study of JADE101. The data are expected to define the dosing strategy and further characterize JADE101’s clinical profile as a potentially differentiated, disease-modifying anti–A Proliferation-Inducing Ligand (APRIL) monoclonal antibody for the treatment of immunoglobulin A nephropathy (IgAN).

Jade Biosciences will host a conference call and webcast on Monday, June 1, 2026, at 8:00 a.m. ET to discuss the JADE101 clinical data.

Investors and the general public are invited to listen to the live webcast and may register on the “Events and Presentations” page of the company’s website atJadeBiosciences.com. To join the live conference call, participants must registerhere. Upon registering, participants will receive dial-in details and a unique PIN to access the call. A replay of the webcast will be available on the Jade website shortly after the call concludes.

IgAN is a chronic autoimmune kidney disease that affects approximately 169,000 people in the U.S. and is most often diagnosed in young adults. The disease is characterized by the deposition of pathogenic IgA-containing immune complexes in the kidneys. These deposits can lead to increased protein in the urine, also known as proteinuria, declining kidney function, and potentially end-stage kidney disease requiring dialysis or a transplant. IgAN often requires lifelong treatment to preserve kidney function and prevent progression to kidney failure.

JADE101 is a fully human monoclonal antibody that selectively blocks APRIL with ultra-high binding affinity and is engineered for half-life extension. Preclinical studies demonstrated potent, sustained IgA suppression after a single dose in non-human primates, with a serum half-life of approximately 27 days. JADE101 was designed to avoid formation of high molecular weight immune complexes, with the goal of supporting predictable pharmacokinetics and reduced immunogenicity risk. Its differentiated pharmacokinetic and pharmacodynamic profile supports the potential for infrequent and convenient subcutaneous dosing, an important consideration for a condition often diagnosed in young adulthood and potentially requiring life-long treatment.

About Jade Biosciences, Inc.Jade Biosciences is a clinical-stage biotechnology company focused on developing best-in-class therapies that address critical unmet needs in autoimmune diseases. Jade’s lead candidate, JADE101, targets the cytokine APRIL, and is currently being evaluated for the treatment of immunoglobulin A nephropathy. Jade’s pipeline also includes JADE201, an afucosylated anti-BAFF-R monoclonal antibody, as well as JADE301, an undisclosed antibody program. Jade was launched based on assets licensed from Paragon Therapeutics, an antibody discovery engine founded by Fairmount. For more information, visitJadeBiosciences.comand follow the Company onLinkedIn.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, how the data from the ongoing Phase 1 healthy volunteer study of JADE101 will characterize JADE101’s clinical profile; the expected benefits or opportunities with respect to JADE101; the potential of JADE101 and Jade’s other product candidates to become best-in-class therapies; and the potential therapeutic uses, efficacy, durability, safety profiles, and dosing of JADE101. 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 risks that the ongoing and any future clinical trials of JADE101 may be delayed or may not demonstrate desirable efficacy or clinical profile; adverse events and safety signals may occur; Jade’s product candidates may fail in development, may not receive required regulatory approvals, or may be delayed to a point where they are not commercially viable; enrollment or regulatory challenges; 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 March 31, 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. This communication does not purport to summarize all of the conditions, risks and other attributes of an investment in Jade.