Jade Biosciences (JBIO) Study update summary

Key study results and objectives

• JADE101 Phase 1 trial in healthy volunteers showed rapid, deep, and durable IgA reductions of ~70% at 12 weeks with the 700 mg dose, outperforming first-generation anti-APRILs and supporting a 12-week maintenance dosing interval.

• No serious or severe adverse events, deaths, or discontinuations occurred; all adverse events were mild or moderate, with no hypogammaglobulinemia or significant immunogenicity impact.

• JADE101 demonstrated ultra-high binding affinity, extended half-life (24.2 days at 700 mg), and efficient target engagement, enabling infrequent dosing and best-in-class IgA lowering potency.

• Pharmacodynamic modeling and biomarker data predict best-in-class efficacy for IgAN, supporting a Q12-week dosing regimen.

• IgA-lowering potency was 379-fold higher than sibeprenlimab and 26-fold higher than povetacicept.

Study design and methodology

• First-in-human, randomized, double-blind, placebo-controlled, single ascending dose study in 32 healthy adults, with four cohorts (175, 350, 700, 1400 mg) and up to 8 months follow-up.

• Primary objective: safety and tolerability; secondary: pharmacokinetics and pharmacodynamics; also assessed immunogenicity and IgA reduction.

• High concentration formulation allows 350 mg to be delivered in a single injection, compatible with prefilled syringe or auto-injector.

• Baseline characteristics were balanced and representative, supporting generalizability.

Safety and tolerability

• No severe adverse events, deaths, or discontinuations; all treatment-emergent adverse events were mild or moderate.

• No clinically significant changes in ECGs, vitals, or safety labs; no cases of IgG ≤3 g/L or hypogammaglobulinemia.

• Injection site reactions were mild or moderate and infrequent.

• Most common adverse events included headache (25%), upper respiratory tract infection (21.9%), injection site erythema (9.4%), oropharyngeal pain (9.4%), and pyrexia (9.4%).

• No apparent impact of anti-drug antibodies on pharmacokinetics or pharmacodynamics.