A Phase 2 interventional study of ARGX-121 and Placebo in Immunoglobulin A Nephropathy (IgAN), sponsored by argenx. Recruiting at 11 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-27.
Sponsored by argenx · Phase 2, Interventional, and Treatment
The study will assess how ARGX-121 affects immunoglobulin A nephropathy (IgAN) disease outcomes, such as renal function, how it is distributed and eliminated from the body, and how the immune system responds in adults with IgAN.
While in the study, participants will continue to receive their usual medical care and medications for IgA nephropathy, unless the study doctor confirms otherwise.
The study will include a double blinded period, followed by an active drug period, and conclude with a follow up period. The total study duration for participants will be approximately 72 weeks, with a maximum of 52 weeks on ARGX-121.
275 studies on the registry are indexed under Glomerulonephritis, IGA; 107 are open to participants now.
This study's planned enrollment of 120 is above the median of 62 across 221 interventional studies indexed under Glomerulonephritis, IGA.
Browse Glomerulonephritis, IGA studies →argenx is the lead sponsor of 87 studies on the registry; 29 are open to participants now.
Of its 22 completed or terminated interventional studies of FDA-regulated products, 16 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants will receive ARGX-121 in subcutaneous injections during the double blinded treatment period and active only treatment periods (Total of 52 weeks)
Biological: ARGX-121
Participants receive placebo for the double-blinded period of 24 weeks, followed by subcutaneous injections of ARGX-121 during the active only treatment period of 28 weeks.
Biological: ARGX-121 · Biological: Placebo
Subcutaneous Injection of ARGX-121
Subcutaneous Injection of Placebo
Change in proteinuria from baseline to week 24 as measured by the log-transformed urine protein-to-creatinine ratio (UPCR) derived from 24-h urine collection.
UPCR is urine protein-to-creatinine ratio
Time frame: Up to 24 weeks
Total annualized rate of change (slope) in the estimated glomerular filtration rate (eGFR) at week 52
Time frame: 52 weeks
Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs)
Time frame: Up to 68 weeks
Cmax (ARGX-121 maximum observed concentration) in serum
Time frame: Up to 68 weeks
Percentage change in total IgA from baseline over time in serum
Time frame: Up to 68 weeks
Percentage change in Gd-IgA1 from baseline over time in serum
Gd-IgA1 means galactose-deficient immunoglobulin A1
Time frame: Up to 68 weeks
Percentage change in total IgG from baseline over time in serum
Time frame: Up to 68 weeks
Incidence of antidrug antibodies (ADA) against ARGX-121 in serum
Time frame: Up to 68 weeks
Plan to share: No
No publications or documents are linked to this record.
Start is estimated for Nov 2026; primary completion for Oct 2029, 35 months later.
Of 41 phase 2 interventional studies under Glomerulonephritis, IGA, half reached primary completion within 33 months of starting (the median), counting those still running; a quarter within 17 and three quarters within 50. This study's planned 35 months is close to that.
Start moved once since we started tracking on Sep 25, 2026: Oct 2026 → Nov 2026, on Oct 27, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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