Jade Biosciences (NASDAQ:JBIO) said interim results from a Phase 1 healthy volunteer study of JADE101 showed rapid and durable reductions in serum IgA, supporting the company’s plan to advance the antibody into patient studies for IgA nephropathy.
Chief Executive Officer Tom Frohlich said JADE101, a fully human monoclonal antibody designed to selectively inhibit APRIL, “exceeded our expectations” in the Phase 1 trial. APRIL is described by the company as a key driver of pathogenic IgA production in IgA nephropathy, a progressive autoimmune kidney disease that can lead to kidney failure.
Frohlich said the Phase 1 findings support the potential for maintenance dosing every 12 weeks with a single subcutaneous injection. He emphasized that the company views the results as translationally relevant because IgA reductions in healthy volunteers have historically correlated with biomarker and clinical responses in IgA nephropathy patients.
Phase 1 Study Shows Dose-Dependent IgA Reductions
Andrew King, Jade’s President of Research and Development, said the first-in-human study was a randomized, double-blind, placebo-controlled, single ascending dose trial in 32 healthy volunteers. Participants received one subcutaneous dose of JADE101 or placebo across four dose cohorts: 175 mg, 350 mg, 700 mg and 1,400 mg.
King said reductions in IgA of at least 50% were observed at all dose levels tested. At the 700 mg dose, which the company plans to use as an induction dose in Phase 2 and Phase 3 trials, JADE101 produced an approximately 70% reduction in serum IgA that was sustained at 12 weeks after dosing.
Jade said its planned regimen in IgA nephropathy includes a 700 mg induction dose followed by 350 mg maintenance dosing beginning four weeks later. The company plans to evaluate maintenance dosing every eight weeks and every 12 weeks in patient trials.
King said pharmacodynamic modeling suggests that 350 mg maintenance dosing every 12 weeks could sustain the deep IgA reductions induced by the 700 mg induction dose. He said the every-eight-week arm is intended to test whether more intensive dosing provides any added clinical benefit and to support formal dose-finding expectations from regulators.
Safety Profile Described as Favorable
Jade reported no deaths, no serious adverse events, no severe treatment-emergent adverse events and no discontinuations due to adverse events in the Phase 1 study. King said all treatment-emergent adverse events were mild or moderate in severity.
Across the full study population, 24 of 32 participants, or 75%, experienced at least one treatment-emergent adverse event. The most common events occurring in more than two participants included headache, upper respiratory tract infection, injection site erythema, oropharyngeal pain and pyrexia.
King said JADE101 was well tolerated locally after subcutaneous administration. Injection site erythema was reported in three of 32 participants, or 9%, and mild injection site pain was reported in one participant, or 3%.
The company also reported no cases of hypogammaglobulinemia, defined as IgG of 3 grams per liter or less. King said IgG reductions were modest and consistent with the selective anti-APRIL mechanism of action. Jade also observed reductions in IgM and an approximately 50% reduction in IgE.
King said no apparent impact of anti-drug antibodies on pharmacokinetics or pharmacodynamics had been observed. In response to an analyst question, he said Jade had not disclosed anti-drug antibody rates because the study is ongoing.
Company Highlights Pharmacokinetic Differentiation
Jade said JADE101 demonstrated dose-dependent exposure and an extended half-life of 24.2 days. King compared that with publicly reported data for earlier anti-APRIL agents, while cautioning that cross-trial comparisons have limitations.
The company said JADE101 produced rapid and complete suppression of serum free APRIL across all evaluated doses, with complete suppression observed as early as two hours after subcutaneous administration. At the 700 mg dose, greater than 90% APRIL suppression was sustained for a median of 85 days, based on the company’s analysis.
Frohlich said the antibody’s design includes ultra-high affinity binding to APRIL, selectivity for APRIL and a half-life extension modification intended to support longer dosing intervals. He said the profile could be important in IgA nephropathy because patients are often diagnosed as young adults and may need treatment over decades.
JUNIPER Phase 2 Trial Underway
Jade recently initiated the Phase 2 JUNIPER trial of JADE101 in IgA nephropathy and said the first participant has been dosed. King described JUNIPER as an open-label trial enrolling adults with biopsy-confirmed primary IgA nephropathy who have a urine protein-to-creatinine ratio of at least 0.75 grams per gram and an eGFR of 30 or higher despite stable standard of care for at least 12 weeks.
The company aims to enroll 30 participants. All participants are expected to receive a 700 mg induction dose and then be randomized one-to-one to 350 mg maintenance doses every eight weeks or every 12 weeks for a 100-week treatment period.
Jade expects to report interim clinical data from JUNIPER in 2027. King said the first disclosure is expected to be “biomarker rich” and include IgA, pathogenic IgA measures, UPCR, eGFR and safety data.
Frohlich said Jade also plans to initiate a Phase 3 pivotal trial of JADE101 in the first half of 2027, pending FDA requirements. During the question-and-answer session, he said the company has not yet received FDA guidance on the Phase 3 design, but suggested a trial could potentially be smaller than earlier large studies in the class, possibly “in the 400-patient range,” including two dose arms.
Frohlich also said Jade estimates the U.S. IgA nephropathy market could exceed $20 billion. The company reported that its cash runway is expected to extend into the first half of 2028 while it advances JADE101 and other programs, including JADE201 and JADE301.
About Jade Biosciences (NASDAQ:JBIO)
Jade Biosciences, Inc is a clinical‐stage biotechnology company focused on the discovery and development of novel therapeutics for inflammatory skin diseases and chronic itch. Leveraging a small‐molecule platform, the company seeks to address significant unmet needs in dermatology by targeting key pathways involved in pruritus and skin inflammation. Its research efforts are centered on identifying and advancing molecules that can modulate receptor activity in the skin, with a goal of improving safety and efficacy compared to existing treatments.
The company’s lead programs are built around proprietary compounds designed to penetrate the epidermal barrier and selectively inhibit molecular drivers of itch and inflammation.
This instant news alert was generated by narrative science technology and financial data from MarketBeat in order to provide readers with the fastest reporting and unbiased coverage. Please send any questions or comments about this story to contact@marketbeat.com.
The article "Jade Biosciences’ JADE101 Delivers Deep IgA Cuts, Clearing Path for Kidney Trials" first appeared on MarketBeat.
