
JADE101 Phase 1 Interim Data
Conference Call June 1, 2026 Nasdaq: jbio Exhibit 99.1

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guarantee the accuracy or completeness of such information contained in this presentation. This presentation contains comparisons of data across separate, non-head-to-head studies. No head-to-head study has been conducted comparing JADE101 to
other candidates or approved agents. Differences may exist between study designs, patient characteristics and other factors, and caution should be exercised in drawing any conclusions from a comparison of the data across studies as cross-study
comparisons are inherently limited and such data may not be directly comparable. In addition, data from third party products have been extracted via digitization and represent approximate values.

JADE101 Phase 1 study met or exceeded
objectives JADE101 Clinical data support potential for every-12-week subcutaneous dosing with best-in-class, disease-modifying potential Data cut off: April 14, 2026 SC – Subcutaneous; HV – Healthy Volunteer; TMDD – Target-Mediated
Drug Disposition; ADA – Anti-Drug Antibodies; PK – Pharmacokinetics; PD – Pharmacodynamics; mAb – Monoclonal Antibody; IgA – Immunoglobulin A; APRIL – A Proliferation-Inducing Ligand; fAPRIL – Free A
Proliferation-Inducing Ligand; Q8W – Every 8 Weeks; Q12W – Every 12 Weeks; sibeprenlimab (Sibe); povetacicept (Pove); zigakibart (Ziga); Data on Sibe and Pove from third-party data; Reported half-life of Sibe 9.3 days (Voyxact,
2025) and Pove 2.8 days (Davies, 2024). Sibe TMDD threshold based on a visual estimate of third-party data. No head-to-head study has been conducted comparing JADE101 to other candidates or approved agents. Differences exist between study designs,
patient characteristics and other factors, and caution should be exercised in drawing any conclusions from a comparison of the data across studies as cross-study comparisons are inherently limited and such data may not be directly
comparable. Endpoint JADE101 Objective Dosing Single SC maintenance dose Q8W Safety Favorable safety profile consistent with selective anti-APRIL mechanism Pharmacodynamics ≥55% IgA reduction sustained for ≥8 weeks Rapid,
complete and sustained suppression of fAPRIL Pharmacokinetics Extended half-life TMDD mitigation Minimal ADA impact on exposure JADE101 DATA Potential for single SC maintenance dose Q12W Favorable safety profile; well-tolerated at all tested doses
~70% IgA reduction sustained at 12 weeks at 700 mg; modeled to be maintained with single SC 350mg Q12W maintenance dose IgA-lowering potency ~379-fold higher than sibeprenlimab; ~26-fold higher than povetacicept Rapid, complete and sustained
suppression of fAPRIL ~8.7 fold longer half-life than povetacicept; ~2.6 fold longer than sibeprenlimab TMDD threshold estimated ~2.5-fold lower than sibeprenlimab No apparent impact of ADA observed on PK or PD

Half-life extension through validated
YTE Fc modification Longer exposure intended to maximize clinical activity and reduce dosing interval to no more frequently than every 8 weeks Potentially best-in-class properties of JADE101 Fully-human, ultra-high binding affinity, and extended
half-life Notes: Jade and its licensor, Paragon, have filed patent applications covering the subject matter of JADE101. No head-to-head clinical trials have been conducted between JADE101 and the referenced drug candidates. Cross-trial
comparisons are inherently limited and presented for hypothesis-generating purposes only. fM – Femtomolar Ultra-high (fM) APRIL binding affinity Binds APRIL to neutralize activity Selective to APRIL to avoid unnecessary immune suppression
Greater APRIL binding affinity than sibeprenlimab (~750x), zigakibart (~2,000x), and povetacicept (~20x) Novel epitope discovered through de novo campaign to achieve first fully-human, potentially best-in-class anti-APRIL mAb Jade101

IgAN is a $20B+ potential market in
the U.S. alone ~169K+ IgAN patients in the U.S., with 60-75% requiring treatment per international guidelines ~1M+ global patients, significant ex-U.S. market potential Notes: Per KDIGO guidelines, treatment should be initiated in all cases
where patients have proteinuria ≥0.5 g/day. U.S. prevalence estimate from FDA; EU prevalence estimate from EMA; Japan / China prevalence estimates from a Novartis presentation. Estimated pricing of ~$360K-$390K per year based on Voyxact.
Sources: 2023 Pitcher (CJASN); FDA Reviews for Filspari / Tarpeyo; EMA; Novartis data publicly disclosed; 2018 Schena (Seminars in Nephrology); Reuters IgAN - IgA nephropathy Jade101

High lifetime risk of end-stage kidney
disease A need for effective and convenient therapies for lifelong treatment IgAN is typically diagnosed in young adults between the ages of 16 and 35; higher proteinuria is associated with greater risk of kidney failure Lifetime
risk of progression to end-stage kidney disease begins at low proteinuria thresholds. Notes: Per KDIGO guidelines, treatment should be initiated in all cases where patients have proteinuria ≥0.5 g/day. Sources: 2023 Pitcher (CJASN);
2018 Schena (Seminars in Nephrology); Reuters; American Kidney Fund (Accessed May 2026) Jade101 IgAN is a progressive autoimmune kidney disease requiring lifelong treatment, with significant need for well-tolerated, disease-modifying therapies
that offer convenient dosing.

Updated KDIGO guidelines position the
anti-APRIL class as the foundational therapy in IgAN KDIGO updates: Expected to increase IgAN diagnosis Expand at-risk patient population requiring treatment Lower proteinuria treatment target to <0.5 g/day, preferably <0.3 g/day Require
targeted therapies that reduce pathogenic IgA Sources: KDIGO Commentary 2026; KDIGO 2025 Guidelines; 2023 Mathur (NEJM); Jade analysis. KDIGO – Kidney Disease Improving Global Outcomes. Jade101 Drivers of nephron loss In all patients
these should be addressed simultaneously Reduce pathogenic forms of IgA and IgA immune complex formation Treatment strategies IgAN patients at risk of progressive kidney function loss Manage the IgAN-specific drivers for nephron loss Manage the
generic response to IgAN-induced nephron loss Cardio-vascular risk reduction Reduce glomerular hyperfiltration and the impact of proteinuria on the tubulointerstitium Blood pressure control Reduce glomerular inflammation B cell modulators, including
APRIL inhibitors

IgA responses are consistent between
HVs and IgAN patients and predictive of clinical activity IgA reduction in HVs is highly correlated with IgA reduction in IgAN patients at multiple time points… …and early IgA reduction further correlates with W36 UPCR reduction, in IgAN
patients Jade101 Notes: Sibeprenlimab Phase 2 (IV) and Phase 3 (SC) IgAN data are included. The Phase 2 data are averages of the 4 mg/kg and 8 mg/kg cohorts (HV IV data is from the 6 mg/kg group); the two cohorts saw effectively equivalent IgA
reduction at weeks 2, 4, and 8. Zigakibart (Ziga) UPCR data is at W52. Atacicept (Ataci) IgAN W8 is average of W4 and W12 datapoints. Datapoints extracted via digitization and represent approximate values. The company does not possess the underlying
raw third-party data. Trend lines are best linear fit. These data are derived from different trials at different points in time, with differences in methodology, design and populations. As a result, cross-trial comparisons are inherently limited.
Sources: 2025 Gufford (ASN Presentation); Voyxact 2025 UPCR – Urine Protein-to-Creatinine Ratio MEAN % CHG FROM BSL IN IgA IN IgAN PTS MEAN % CHG FROM BSL IN IgA IN HVS MEAN IgA % REDUCTION (WEEK 8) GEOMETRIC MEAN UPCR % REDUCTION (WEEK 36)
r=0.92 r=0.92

JADE101 Interim Phase 1 Data

JADE101 Phase 1 study ongoing
Design Randomized, double-blind, placebo-controlled Single ascending dose Subcutaneous administration (175 mg/mL) Population 32 healthy adult volunteers N=8 per cohort (6:2 active:placebo) Objectives Primary: Safety and tolerability Secondary:
Pharmacokinetics Exploratory: Pharmacodynamics (APRIL, IgA, immunoglobulins); Immunogenicity Dose levels and length of follow-up to date Phase 1 175MG SC: N = 6:2 Follow-up: ~8 months 350MG SC: N = 6:2 Maintenance dose Follow-up: ~7 months Planned
maintenance dose in Phase 2 and Phase 3 700MG SC: N = 6:2 Induction dose Follow-up: ~6 months Planned induction dose in Phase 2 and Phase 3 1,400MG SC: N = 6:2 Follow-up: ~5 months Notes: ClinicalTrials.gov ID: NCT07059312. Numbers
presented as subjects receiving JADE101 relative to placebo. Each cohort included a sentinel group, n = 2 (1 JADE101, 1 placebo); remainder dosed after safety clearance.

Baseline characteristics were
typical of healthy volunteers Phase 1 Data cutoff: April 14, 2026 BMI – Body Mass Index JADE101 and Placebo 175 mg 350 mg 700 mg 1400 mg All cohorts N 8 8 8 8 32 Age, (yr), Mean (SD) 38.0 (7.86) 44.5 (9.87) 28.0 (9.04) 37.6 (13.70) 37.0
(11.51) Female N (%) 2 (25) 6 (75) 3 (38) 5 (63) 16 (50) White N(%) 5 (63) 6 (75) 4 (50) 3 (38) 18 (56) Asian N (%) 2 (25) 1 (13) 3 (38) 1 (13) 7 (22) BMI, (kg/m2) Mean (SD) 25.5 (2.70) 26.7 (2.88) 25.9 (3.05) 24.2 (3.25) 25.6 (2.97)

JADE101 demonstrated favorable
safety profile and was well tolerated across all evaluated doses No severe AEs or deaths All TEAEs were mild/moderate in severity No clinically significant changes in ECGs or vitals No trends of signals in safety labs No cases of IgG
≤3 g/L Well-tolerated locally by SC injection 3/32 (9%) mild (2)/moderate (1) injection site erythema 1/32 (3%) mild injection site pain No apparent impact of anti-drug antibodies was observed on PK or PD Healthy Volunteer SAD Safety
Summary Phase 1 JADE101 and Placebo 175 mg 350 mg 700 mg 1400 mg All cohorts N 8 8 8 8 32 ≥ 1 TEAE, n (%) 6 (75) 6 (75) 5 (63) 7 (88) 24 (75) ≥ 1 SAE, n 0 0 0 0 0 ≥ 1 severe TEAE, n 0 0 0 0 0 Discontinued due to AE 0 0 0 0 0 TEAEs
in the pooled safety analysis occurring in > 2 participants were headache (25%), upper respiratory tract infection (21.9%); injection site erythema, oropharyngeal pain, and pyrexia (9.4% each) Data cutoff: April 14, 2026 AE – Adverse event;
ECG – Electrocardiogram; SAD – Single Ascending Dose; SAE – Serious Adverse Event; TEAEs – Treatment Emergent Adverse Events

JADE101 single dose IgA reductions
exceeded those reported with first-generation molecules Data cutoff: April 14, 2026 Source: Internal data; IgA responses estimated via noncompartmental analysis of individual JADE101 profiles and internal analyses of mean reported profiles of
povetacicept (Davies, 2024) and sibeprenlimab (Mathur,2022; Zhang,2023). Povetacicept and sibeprenlimab data points extracted via digitization and represent approximate values. The company does not possess the underlying raw third-party data. No
head-to-head study has been conducted comparing JADE101 to other candidates or approved agents. Differences exist between study designs, patient characteristics and other factors, and caution should be exercised in drawing any conclusions from a
comparison of the data across studies as cross-study comparisons are inherently limited and such data may not be directly comparable. First-gen – First Generation Prolonged IgA reductions of ~70% following a single dose of JADE101 Reductions
exceeded those reported for first-gen agents Induction dose of 700 mg expected to drive ~70% IgA reductions, with 350 mg maintenance dose predicted to sustain this reduction Largest reported magnitude of IgA lowering effect with a single dose for an
anti-APRIL or dual APRIL/BAFF IgA reductions sustained at 12 weeks at 700 mg Phase 1 MEAN IgA CFB (%) Nominal Time (week) IgA Change from Baseline by Dose IgA reduction in Healthy Volunteers MEAN IgA CFB (%) Sibeprenlimab Povetacicept Jade101
700mg single dose predicted to reflect IgA responses with Q12W maintenance dosing (700mg induction + 350mg maintenance)

Ultra-high APRIL binding affinity
predicted JADE101’s enhanced in vivo potency to lower serum IgA in humans JADE101 has shown rapid, deep and sustained IgA depletion JADE101 demonstrated compelling in vivo potency to lower IgA PHASE 1 APRIL KD(pM) IgA EC50 (ηM) Jade101
Pove Sibe Ziga Ataci IgA EC50 (nM) 0.010 0.27 3.9 16.4 72.9 IgA EC50 v JADE101 n/a 26x 379x 1,595x 7,091x Dosing Interval Potentially Q12W Q4W Q4W Q2W Q1W Data cutoff: April 14, 2026; Source: Internal data; Benchmarks manufactured based on publicly
available sequences. Atacicept APRIL KD 672 pM (Vera internal data). IgA EC50 estimates calculated using compartmental PK models linked to indirect response models to describe IgA kinetics built using JADE101-01 data or published PK and IgA
concentration-time profiles for each molecule. Sibe (Mathur, 2022; Zhang, 2023); Ziga (Kooienga, 2025); Pove (Davies, 2024); Atacicept (Willen, 2020, Nestorov, 2008/2010, Munafo, 2007). Data points extracted via digitization and represent
approximate values. The company does not possess the underlying raw third-party data. These data are derived from different trials at different points in time, with differences in trial design and populations. No head-to-head clinical
trials of JADE101 and other agents have been conducted. EC – Effective Concentration; nM – Nanomolar (Q1W) (Q2W) (Q4W) (Q4W) Potentially Q12W APRIL Binding Affinity and IgA Lowering Potency

0 -10 -30 -50 -70 0 8 16 24 32 40
48 JADE101 350 mg SC Q12W maintenance Pove 80 mg SC Q4W Sibe 400 mg SC Q4W JADE101 PD modeling supports Q12W maintenance dosing Deeper IgA reductions simulated over first-generation anti-APRILs JADE101 induction dose (700 mg) predicted to rapidly
maximize IgA depletion >70% IgA reductions projected at steady state with a single subcutaneous maintenance injection (350mg) every 12 weeks IgA reductions modeled to be faster and deeper than first generation
anti-APRIL or dual APRIL/BAFF PHASE 1 Data cutoff: April 14, 2026. Source: Internal data; Solid lines represent the median and shaded area represents the 5th and 95th prediction intervals across 500 simulated trials. JADE101 population-based
simulations informed by interim biomarker rich healthy volunteer data obtained in JADE101-01 integrated with data available in the public domain. Sibeprenlimab and povetacicept simulations conducted via population-based approaches using internal
models informed by data available in the public domain (Pove: Davies 2024; Sibe: FDA Review 2025). Underlying povetacicept and sibeprenlimab data points extracted via digitization and represent approximate values. The company does
not possess the underlying raw third-party data. Modeled data may not be realized in actual clinical studies and may not accurately represent performance of third-party products. JADE101 Q12W Dosing (Year 1) 700mg Induction 350mg
Maintenance PREDICTED IgA CFB (%) Time (week) Simulated IgA vs Time – 48 weeks

Pharmacokinetics fAPRIL JADE101
CONC. (μg/mL) IgA reductions for 12 weeks enabled by dose-dependent PK and rapid, complete, and sustained fAPRIL suppression Date cutoff: April 14, 2026; Source: Internal data. Half-life dependent on dose and dose interval; JADE101 half-life
measured at 700 mg induction dose. Sibeprenlimab TMDD threshold based on visual estimate of third-party data. Duration of fAPRIL response (>90%) estimated via noncompartmental analysis of individual JADE101 participant profiles. No head-to-head
study has been conducted comparing JADE101 to other candidates or approved agents. Differences exist between study designs, patient characteristics and other factors, and caution should be exercised in drawing any conclusions from a comparison of
the data across studies as cross-study comparisons are inherently limited and such data may not be directly comparable. Phase 1 fAPRIL CFB (%) Time (week) ~8.7 fold longer half-life than povetacicept; ~2.6 fold longer than sibeprenlimab JADE101
half-life: 24.2 days JADE101 TMDD threshold estimated ~2.5-fold lower than sibeprenlimab PK profiles of first-gen anti-APRIL mAbs strongly influenced by TMDD Deep serum fAPRIL suppression as rapidly as 2 hours post SC dose administration >90%
APRIL suppression sustained for a median of 85 days at 700 mg Time (week)

Changes in IgG, IgM and IgE were
consistent with the selective anti-APRIL MoA IgG IgM Magnitude of IgG-lowering consistent with relatively IgG-sparing selective- anti-APRIL MoA No cases of IgG ≤ 3 g/L Substantial IgM and IgE reductions PHASE 1 IgE IgG CFB (%) Time (week) IgM
CFB (%) Time (week) IgE CFB (%) Time (week) Data cutoff: April 14, 2026 Source: Internal JADE101-01 data. IgG – Immunoglobulin G; IgM – Immunoglobulin M; IgE – Immunoglobulin E; MoA – Mechanism of Action

JADE101 Next Steps

Plan to evaluate two dosing
regimens (Q12W and Q8W) in Phase 2 and Phase 3 Two dose Phase 3 may enable an accelerated Phase 3 initiation without awaiting Phase 2 data Supports global regulatory expectations for dose-finding Initial induction dose intended to drive ~70%
IgA reductions at earlier timepoints Induction dose is 700 mg, followed by Q12W or Q8W maintenance dosing (350 mg) beginning at Week 4 Q12W dosing expected to optimize clinical activity and convenience for patients Next steps Year 1 Year 2 JADE101
Q12W Pove/Sibe Q4W Ataci/Ziga QW/2W Notes: JADE101 projected dosage frequency based on internal population pharmacodynamic modeling and dosing schedules remain subject to further clinical investigation. No head-to-head study has been
conducted comparing JADE101 to other candidates or approved agents. Differences exist between study designs, patient characteristics and other factors, and caution should be exercised in drawing any conclusions from
a comparison of the data across studies as cross-study comparisons are inherently limited and such data may not be directly comparable.

JADE101 Phase 2 IgAN patient trial
initiated; interim data anticipated in 2027 Design Randomized, open-label Subcutaneous administration Population Adults with IgAN within 5 yrs Proteinuria ≥0.75g/g eGFR ≥30mL/min/m2 Stable SOC ≥12 weeks Objectives Safety and
tolerability UPCR-24 over time (<0.5 g/day, <0.3 g/day) eGFR over time Next steps Week 0 Induction Dose 700 mg Q8W (N=~15) 350 MG (to Week 100) Week 4 Maintenance Dosing 350 mg Q12W (N=~15) 350 MG (to Week 100) Safety Follow Up 24 weeks after
last dose ClinicalTrials.gov ID: NCT07541287 SOC – Standard of Care; eGFR – Estimated Glomerular Filtration Rate Open-label Extension Or

Program MOA preclinical Phase 1
Phase 2 Phase 3 Potential Indications JADE101 anti-APRIL IgAN JADE201 anti-BAFF-R Multiple systemic AI diseases JADE301 Undisclosed Undisclosed Advancing potentially best-in-class therapies for autoimmune diseases Well-capitalized with $311 million
in cash(1); runway expected into 1H 2028 Notes: Jade has entered into exclusive license agreements with Paragon Therapeutics for JADE101 and JADE201. Jade holds an exclusive option to license JADE301 from Paragon. Jade has not yet entered
into a license agreement with respect to JADE301. AI – Autoimmune; BAFF-R – B cell-Activating Factor Receptor (1) Cash, cash equivalents and investments as of March 31, 2026. Candidates designed to maximize clinical activity and allow
patient friendly, infrequent dosing Company overview Development candidates from Paragon Jade101 Interim Phase 1 Data: Q2 2026 Interim Phase 2 Data: 2027 Phase 3 Initiation: 1H 2027 Jade201 Interim Phase 1 Data: 2027 Jade301 Phase 1 Initiation : 1H
2027 Expected Milestones:

Thank you JadeBiosciences.com
info@jadebiosciences.com Nasdaq: jbio