Jade Biosciences has dosed the first participant in its Phase II JUNIPER clinical trial, evaluating JADE101 for immunoglobulin A nephropathy (IgAN).

The open-label trial aims to assess the antibody’s safety, tolerability, and efficacy in this chronic autoimmune kidney disease.

JADE101 is engineered to selectively block the cytokine A PRoliferation-Inducing Ligand (APRIL), regarded as a driver of pathogenic IgA production in IgAN.

This condition frequently affects young adults and may progress to end-stage kidney disease over time. Jade Biosciences expects interim data from the JUNIPER trial in 2027.

Aiming to examine the safety and tolerability of JADE101, the study will enrol 30 participants diagnosed with IgAN.

Additionally, investigators will analyse changes in urine protein-to-creatinine ratio, a recognised prognostic marker for disease progression, renal function determined by estimated glomerular filtration rate, and resolution of haematuria.

IgA nephropathy is characterised by the deposition of pathogenic IgA-containing immune complexes in the kidneys, resulting in chronic autoimmune kidney disease.

JADE101 is described as a fully human monoclonal antibody that blocks APRIL with ultra-high affinity.

It was designed to prevent the formation of high molecular weight immune complexes, targeting predictable pharmacokinetics and reducing immunogenicity risk.

Its pharmacokinetic and pharmacodynamic properties may allow for infrequent and convenient subcutaneous dosing, an important factor for younger adults who might require lifelong treatment.

Jade Biosciences research and development president Andrew King said: "Preclinical data showed JADE101 has ultra-high binding affinity to APRIL and a differentiated pharmacokinetic and pharmacodynamic profile, supporting the potential to drive deep and sustained IgA reductions and enable patient-friendly subcutaneous dosing of no more frequently than every eight weeks."