Evaluation of Atacicept Administration on Gd-IgA1 Levels in Patients with IgA Nephropathy: A Monthly Dosing Study

The primary objective is to evaluate the effect of atacicept on galactose-deficient IgA1 in patients with IgA nephropathy. The secondary objectives include:

• Assessment of safety and tolerability across different dosing regimens.
• Evaluation of the impact on serum immunoglobulins.
• Analysis of serum pharmacokinetics.
• Assessment of immunogenicity.
• Evaluation of changes in proteinuria.

This clinical trial involves 63 participants diagnosed with IgA nephropathy. The study population consists of adult male and female patients. Eligible individuals must have a diagnosis confirmed by renal biopsy, featuring a urine protein excretion of ≥0.75 g per 24 hours or a urine protein-to-creatinine ratio of ≥0.75 mg/mg. Participants are required to have an estimated glomerular filtration rate of ≥30 ml/min/1.73m2 and must be receiving a stable standard of care regimen. Additionally, systolic blood pressure must be ≤160 mmHg and diastolic blood pressure must be ≤90 mmHg at the time of screening.

This Phase II clinical trial is designed to evaluate the effect of atacicept on Gd-IgA1 levels in patients diagnosed with IgA nephropathy. The study involves the administration of atacicept via subcutaneous injection at a dose of 600 mg every four weeks. Eligible participants must be adults with a confirmed diagnosis of IgA nephropathy through renal biopsy, demonstrating a urine protein excretion of ≥0.75 g per 24-hour or a UPCR of ≥0.75 mg/mg and an eGFR ≥30 ml/min/1.73m2. Participants must also be on a stable standard of care regimen and maintain systolic blood pressure ≤160 mmHg and diastolic blood pressure ≤90 mmHg at the screening visit. The primary endpoint is the assessment of Gd-IgA1 levels through Week 24. Secondary endpoints include the incidence of treatment-emergent adverse events, changes in vital signs, levels of IgG, IgM, and IgA, serum concentration of the test product, anti-drug antibody status, and UPCR values through the end of the study.

The experimental treatment consists of atacicept, provided as a solution for injection in pre-filled syringe. The medication is administered via subcutaneous injection at a dosage of 600 mg. This administration occurs on a monthly schedule, specifically every four weeks.

The efficacy of atacicept in patients with IgA nephropathy is evaluated through several parameters. The primary endpoint consists of measuring Gd-IgA1 levels through Week 24. Secondary endpoints include the assessment of IgG, IgM, and IgA levels through Week 24, as well as monitoring UPCR values until the end of the study. Additionally, the serum concentration of atacicept and anti-drug antibody status are measured through the end of the study.

Safety and clinical changes are monitored via the incidence of treatment-emergent adverse events and changes from baseline in routine laboratory and vital sign parameters.