Treatments for IgA Nephropathy

According to KDIGO, a worldwide organization developing and implementing evidence-based clinical practice guidelines in kidney disease, effective treatment for IgA nephropathy involves two connected goals.

One is slowing the progression of chronic kidney disease (CKD) through measures that lower proteinuria, protect the kidney filters, and reduce ongoing injury, largely considered supportive care. The other, requiring IgA nephropathy-specific medicines, is reducing the production of galactose-deficient IgA1 (Gd-IgA1) and calming the immune pathways that cause inflammation in the kidneys.

Different treatments work on different parts of this strategy. Supportive therapies such as RAAS blockade, SGLT2 inhibitors, blood pressure control, and lifestyle measures focus on preserving kidney function over time. Medicines that target the immune system aim to reduce the upstream drivers of Gd-IgA1 and its immune effects.

Most people benefit from a combination of these approaches.

The renin-angiotensin-aldosterone system (RAAS) helps control blood pressure and pressure inside the kidney filters. Medicines such as ACE inhibitors (angiotensin converting enzyme inhibitors) and ARBs (angiotensin II receptor blockers) lower this internal pressure and reduce protein loss in the urine. Even though they are not approved specifically "for IgA nephropathy" on the label, they are a standard part of care for most people with IgA nephropathy because they help protect kidney function over time.

SGLT2 inhibitors (sodium-glucose cotransporter 2 inhibitors) were first developed to treat diabetes, but they also protect the kidneys. They reduce stress on the filtering units, lower protein leakage, and can slow the decline in kidney function in people with chronic kidney disease. In IgA nephropathy, SGLT2 inhibitors are often added on top of RAAS blockade when kidney function and other factors make their use appropriate, even if the drug label does not mention IgA nephropathy by name. The exact combination depends on the specific IgA nephropathy medicine and its label.

Six medicines are now approved in the United States specifically for adults with primary IgA nephropathy who are at risk of disease progression: Tarpeyo, Filspari, Fabhalta, Vanrafia, Voyxact, and Trutakna. Three have traditional FDA approval based on confirmatory kidney-function data, while three have accelerated approval based primarily on proteinuria reduction with ongoing studies required to confirm long-term clinical benefit. These medicines are not interchangeable, and they are not all used in the same way with RAAS blockade or other supportive therapies. Treatment choices should follow the individual product label and the patient's kidney function, blood pressure, pregnancy risk, and infection risk.

• Generic: budesonide delayed-release capsules / targeted-release formulation budesonide (TRF-budesonide)
• Brand: Tarpeyo; marketed as Kinpeygo in some regions
• Mechanism: a corticosteroid designed to release mainly in the lower small intestine, where a large part of the immune system involved in IgA nephropathy sits.
• Regulatory status (US): received accelerated approval in 2021 to reduce proteinuria in adults with primary IgA nephropathy; the FDA later granted full (traditional) approval in 2023 after confirmatory data.

Viatris is also developing VR-205, a targeted-release budesonide formulation of Nefecon, for adults with IgA nephropathy in Japan. Its phase 3 Japanese study reported positive top-line results in June 2026, and the company is targeting a Japanese New Drug Application by the end of 2026. VR-205 is not a separate U.S.-approved mechanism; it is a regional formulation and development program.

• Generic: sparsentan
• Brand: Filspari (FILSPARI)
• Mechanism: blocks both the endothelin A receptor and the angiotensin II type 1 receptor, directly targeting glomerular injury and protein leakage.
• Regulatory status (US): initially received accelerated approval, then in 2024 gained full FDA approval to slow kidney function decline and reduce proteinuria in adults with primary IgA nephropathy at risk of disease progression.
• Important treatment note: because Filspari combines endothelin and angiotensin-receptor blockade, its current label instructs clinicians to discontinue RAAS inhibitors and endothelin-receptor antagonists before starting Filspari and contraindicates concomitant use of ARBs, ERAs, or aliskiren.

• Generic: atrasentan
• Brand: Vanrafia
• Mechanism: selectively blocks the endothelin A receptor, which is involved in narrowing blood vessels and promoting kidney damage in proteinuric kidney disease.
• Regulatory status (US): received FDA accelerated approval in April 2025 to reduce proteinuria in adults with primary IgA nephropathy at risk of rapid disease progression. Final phase 3 ALIGN data published in 2026 support an effect on slowing kidney function decline, and Novartis has stated it plans to seek traditional approval. It remains an accelerated approval unless and until the FDA grants that supplemental application.

• Generic: iptacopan
• Brand: Fabhalta
• Mechanism: an oral inhibitor of complement factor B, targeting the alternative complement pathway, which is thought to contribute to kidney injury in IgA nephropathy.
• Regulatory status (US): received FDA accelerated approval in August 2024 to reduce proteinuria in adults with primary IgA nephropathy at risk of rapid disease progression. In July 2026, the FDA granted traditional approval to slow kidney function decline in adults with primary IgA nephropathy at risk of disease progression, based on final phase 3 data showing slower decline compared with placebo.

• Generic: sibeprenlimab-szsi
• Brand: Voyxact (VOYXACT)
• Mechanism: a monoclonal antibody that targets APRIL (A Proliferation-Inducing Ligand), a signaling protein involved in the abnormal IgA immune response that drives IgA nephropathy.
• Regulatory status (US): received FDA accelerated approval in November 2025 to reduce proteinuria in adults with primary IgA nephropathy; continued approval depends on confirmation that it slows kidney function decline in long-term follow-up studies. Otsuka has reported positive interim kidney-function data from VISIONARY and begun a rolling supplemental BLA submission seeking traditional approval.

• Generic: atacicept-vymj
• Brand: Trutakna
• Mechanism: a fusion protein that blocks both BAFF and APRIL, aiming to reduce production of Gd-IgA1 and other harmful antibodies.
• Regulatory status (US): received FDA accelerated approval in July 2026 to reduce proteinuria in adults with primary IgA nephropathy at risk for disease progression. Trutakna is injected subcutaneously once weekly. In September 2026, Vera reported final phase 3 ORIGIN 3 data showing slower kidney-function decline through 104 weeks compared with placebo and plans to seek traditional approval. It remains under accelerated approval unless and until the FDA grants that supplemental application. Because it suppresses the immune system, the FDA label warns about infections and reduced immune responses to vaccines, including avoidance of live vaccines during treatment.

Alongside these drug treatments, other measures are important for nearly everyone with IgA nephropathy. These include carefully controlling blood pressure, limiting salt intake, managing cholesterol, treating anemia when present, maintaining a healthy weight, stopping smoking, and staying current with recommended vaccinations. These steps do not replace disease-specific medicines, but they work together with them to protect kidney function and overall health over time.

Clinical trials give people access to investigational IgA nephropathy treatments that are not yet widely available. Many trials study medicines that target specific parts of the immune system or complement system involved in IgA production and kidney injury. Others test new ways to reduce proteinuria or protect kidney function. Participation is voluntary, and each trial has its own eligibility criteria based on kidney function, protein levels, and other health factors. Trials help researchers confirm how well new therapies work and whether they can slow long-term kidney damage. For some patients, a clinical trial may offer an option when standard treatments are not enough. Participation also contributes evidence that may help future patients, including people who cannot enroll because of health criteria, location, or financial constraints.

Most of the medicines listed below are not approved for routine use and are still undergoing evaluation from preclinical development through phase 3 studies. Where a medicine has a regional approval, that status is stated in its entry. These therapies target different parts of the immune system, complement system, disease-driving IgA, or kidney-injury pathways involved in IgA nephropathy.

To see a list of open clinical trials for IgA nephropathy, refer to the IgA Nephropathy Foundation's up-to-date listing.

Because many of these treatments are still experimental, the most important questions are whether they can reliably lower proteinuria, help stabilize kidney function, and maintain an acceptable safety profile over time. Some medicines-such as telitacicept, povetacicept, felzartamab, and mezagitamab-already have encouraging phase 2-3 results. Others, such as BHV-1400, CLYM116, ARGX-121, and PS-002, are earlier in development but aim directly at underlying disease mechanisms.

Access to these investigational therapies is generally limited to clinical trials, and results from ongoing studies will determine which become future treatment options. Decisions about trial participation should consider kidney function, current treatment response, the demands of trial visits, and personal goals.

The following investigational or regionally approved medicines are grouped by the main part of the immune system they target:

These drugs try to interrupt the overactive B-cell signaling that leads to production of disease-causing IgA and Gd-IgA1. They focus on BAFF (B-cell activating factor) and APRIL (a proliferation-inducing ligand), two key signals that help B cells survive and mature. Atacicept is now approved in the United States as Trutakna and is described in the approved-medicine section above; the other medicines in this section remain investigational unless otherwise noted.

Povetacicept (long-acting dual BAFF/APRIL biologic)

• Mechanism: a long-acting agent given by subcutaneous injection (typically every 4 weeks) that blocks both BAFF and APRIL.
• Key data: in the RAINIER phase 3 trial, a prespecified week 36 interim analysis met the primary and secondary endpoints, with a statistically significant and clinically meaningful reduction in proteinuria compared with placebo.
• Status: the FDA accepted Vertex's BLA in June 2026 and assigned a PDUFA target action date of November 30, 2026. The phase 3 trial remains ongoing, and povetacicept is not yet approved for IgA nephropathy.

Telitacicept (TACI-Fc fusion protein)

• Mechanism: a fusion protein that binds and neutralizes both BAFF and APRIL, similar in concept to atacicept but with a different structure.
• Key data: the TELIGAN phase 3 trial in China, published in the New England Journal of Medicine in 2026, found in a prespecified interim analysis that telitacicept produced a substantial reduction in proteinuria at 39 weeks compared with placebo. Kidney function remained largely stable, and serum IgA and Gd-IgA1 levels fell. An exploratory analysis found that the percentage of participants with hematuria decreased from 71% at baseline to 21% at week 39; the relationship between this finding and long-term kidney outcomes remains uncertain.
• Status: China's NMPA granted conditional approval for IgA nephropathy in June 2026. Telitacicept is not approved for IgA nephropathy by the U.S. FDA.

CLYM116 / MIL116 (anti-APRIL "sweeper" antibody)

• Mechanism: an anti-APRIL antibody designed to bind, release, and promote degradation of APRIL rather than simply block it. The goal is to produce deep and durable suppression with less frequent dosing.
• Key data: Climb Bio reported early phase 1 healthy-volunteer data in September 2026, including a projected half-life of about 29 days and company-reported suppression of APRIL, IgA, and Gd-IgA1 after a single dose. These are biomarker and pharmacokinetic findings, not evidence of clinical efficacy in IgA nephropathy.
• Status: the phase 2 NAVIGATE-2 study is ongoing; initial data are anticipated in the first half of 2027, and phase 3 initiation is anticipated in 2027. The public trial record uses the development name MIL116. It is not approved for IgA nephropathy.

JADE101 (anti-APRIL monoclonal antibody)

• Mechanism: a monoclonal antibody designed to selectively block APRIL, aiming to reduce pathogenic IgA production while allowing infrequent subcutaneous dosing.
• Key data: Jade Biosciences reported positive interim phase 1 data, including potent APRIL suppression and a dosing profile intended to support infrequent subcutaneous administration.
• Status: the JUNIPER phase 2 trial in IgA nephropathy is recruiting; interim phase 2 data are expected in 2027.

Zigakibart (BION-1301, anti-APRIL monoclonal antibody)

• Mechanism: a monoclonal antibody that blocks APRIL alone, aiming to reduce survival of plasma cells that make Gd-IgA1.
• Key data: phase 2 results show meaningful proteinuria reductions (roughly 50-55%) and stable eGFR over extended follow-up.
• Status: the BEYOND phase 3 trial is underway to confirm efficacy and safety in a larger, global IgA nephropathy population.

These drugs target the complement system, which amplifies inflammation and tissue injury once immune complexes deposit in the kidney. Different agents act at different "checkpoints" in the complement cascade.

Ebribafusp (AKB-097 / ADX-097; tissue-targeted complement inhibitor)

• Mechanism: an anti-C3d factor H fusion protein designed to localize complement inhibition to affected tissues, including the kidney, while preserving complement activity in the blood.
• Key data: a completed phase 1 study in healthy volunteers found that weekly subcutaneous dosing achieved the company's targeted tissue-exposure profile and was generally well tolerated. These findings do not establish efficacy in IgA nephropathy.
• Status: Akebia dosed the first patient in an open-label phase 2 basket trial in September 2026 for IgA nephropathy, lupus nephritis, and C3 glomerulopathy. The study plans to enroll up to 30 patients and report initial data in 2027. It is not approved for IgA nephropathy.

Ravulizumab (Ultomiris; C5 inhibitor)

• Mechanism: a long-acting monoclonal antibody that blocks complement protein C5, preventing formation of the membrane attack complex and downstream inflammation.
• Key data: in a prespecified interim analysis of the I CAN phase 3 trial, ravulizumab met the interim primary endpoint with a statistically significant and clinically meaningful reduction in proteinuria based on 24-hour UPCR at week 34; reduction was observed as early as week 10.
• Status: the FDA accepted AstraZeneca's supplemental BLA and granted priority review in June 2026. The other primary endpoint, change from baseline in eGFR, will be measured at week 106. A U.S. regulatory decision is expected in the fourth quarter of 2026; ravulizumab is not yet approved for IgA nephropathy.

Cemdisiran (siRNA to C5)

• Mechanism: a small interfering RNA (siRNA) drug that reduces production of C5 in the liver, lowering circulating C5 and dampening terminal complement activity.
• Key data: in a phase 2 trial, cemdisiran reduced proteinuria at around week 32 and was generally well tolerated, with stable kidney function.
• Status: the IgA nephropathy phase 2 study is listed as terminated and is no longer recruiting. Cemdisiran remains investigational for IgA nephropathy, and the page should not imply that an active IgAN development program is ongoing.

Sefaxersen (RO7434656, IONIS-FB-LRx; antisense to complement factor B)

• Mechanism: an antisense oligonucleotide that lowers production of factor B, a key component of the alternative complement pathway.
• Key data: phase 2 data show a roughly 40-45% mean reduction in 24-hour proteinuria at ~29 weeks, with strong suppression of alternative-pathway activity and stable eGFR.
• Status: remains in development, with the phase 3 IMAGINATION study recruiting. It is not approved for IgA nephropathy.

HSK39297 (oral complement factor B inhibitor)

• Mechanism: an oral small-molecule inhibitor of complement factor B, intended to reduce alternative-pathway complement activation.
• Key data: phase 2 and phase 3 studies use proteinuria and kidney-function measures, including UPCR and eGFR, to evaluate whether factor B inhibition can reduce kidney injury in primary IgA nephropathy.
• Status: phase 2 data collection is complete, an open-label phase 2 long-term extension study is recruiting participants who completed the earlier phase 2 trial, and a separate phase 3 trial in primary IgA nephropathy is recruiting. It is not approved for IgA nephropathy.

ADX-038 (siRNA to complement factor B)

• Mechanism: a small interfering RNA (siRNA) therapy designed to silence complement factor B in the liver and selectively suppress alternative-pathway complement activity.
• Key data: a phase 1 study in healthy volunteers found that a single dose produced near-complete alternative-pathway inhibition for about six months while leaving classical-pathway activity unchanged. The study was generally well tolerated, but no patient efficacy data in IgA nephropathy have been reported.
• Status: phase 2 studies are recruiting in IgA nephropathy and other complement-mediated kidney diseases, including a Chinese study evaluating ADX-038 alone and in combination with telitacicept. It is not approved for IgA nephropathy.

HS-10542 (oral complement factor B inhibitor)

• Mechanism: an oral, once-daily small-molecule inhibitor of complement factor B, intended to suppress alternative- pathway activation.
• Key data: Hansoh reported phase 1 healthy-volunteer data showing a favorable early safety and pharmacokinetic profile with alternative-pathway inhibition. No patient efficacy data in IgA nephropathy have been reported.
• Status: a phase 2 dose-ranging study in primary IgA nephropathy is registered but listed as not yet recruiting. It is not approved for IgA nephropathy.

NTQ5082 (oral complement factor B inhibitor)

• Mechanism: an oral small-molecule inhibitor of complement factor B designed to block the alternative complement pathway.
• Key data: a phase 2 study is evaluating changes in UPCR, eGFR, serum creatinine, and related urine markers in adults with primary IgA nephropathy.
• Status: a phase 2 study is listed but not yet recruiting; not approved for IgA nephropathy.

SLN12140 (selective complement inhibitor)

• Mechanism: a next-generation complement inhibitor designed for selective pathway suppression. Public materials do not yet provide enough detail to describe the target more specifically.
• Key data: no patient efficacy data in IgA nephropathy have been reported.
• Status: a randomized phase 2 study in adults with primary IgA nephropathy in China is listed as not yet recruiting. It is not approved for IgA nephropathy.

BW-40202 (siRNA to complement factor B)

• Mechanism: a small interfering RNA (siRNA) therapy designed to silence CFB mRNA in the liver, lowering serum complement factor B levels and suppressing alternative-pathway activity.
• Key data: Argo has dosed the first patients in phase II studies for paroxysmal nocturnal hemoglobinuria and IgA nephropathy. Earlier preclinical studies reported durable reductions in serum factor B and effective inhibition of the alternative complement pathway.
• Status: investigational siRNA therapy being evaluated in Phase II clinical trials for paroxysmal nocturnal hemoglobinuria (PNH) and IgA nephropathy; not approved for IgA nephropathy.

ARO-C3 (RNAi therapy targeting complement C3)

• Mechanism: an RNA interference (RNAi) drug given by injection that reduces levels of C3, a central hub in the complement cascade, thereby dampening all downstream complement activation.
• Key data: in early IgA nephropathy cohorts, ARO-C3 produced deep and sustained reductions in C3 and alternative-pathway activity, with meaningful reductions in UPCR and stable kidney function.
• Status: the phase 1/2 IgA nephropathy study is completed and no longer recruiting. The early results remain investigational and additional studies would be needed to define long-term efficacy and safety.

Ruxoprubart (NM8074; complement inhibitor)

• Mechanism: an intravenous complement inhibitor being studied for its effects on proteinuria and complement biomarkers in IgA nephropathy.
• Key data: a small open-label phase 2 study is designed to evaluate change in UPCR after 99 days of treatment, with secondary measures including eGFR, serum creatinine, hematuria, Bb, and sC5b-9.
• Status: a phase 2 study is listed but not yet recruiting; not approved for IgA nephropathy.

KP104 (subcutaneous complement inhibitor)

• Mechanism: a subcutaneous complement inhibitor being studied in complement-mediated glomerular diseases, including IgA nephropathy and C3 glomerulopathy.
• Key data: a phase 2 study is designed to evaluate safety, pharmacokinetics, pharmacodynamics, and proteinuria response, with IgA nephropathy enrollment used to select an optimal biologic dose.
• Status: a phase 2 study is listed but not yet recruiting; not approved for IgA nephropathy.

These drugs target plasma cells and other CD38-expressing immune cells that produce large amounts of Gd-IgA1 and related autoantibodies. The goal is to "turn off the factory" making the pathogenic IgA at its source.

Felzartamab (anti-CD38 monoclonal antibody)

• Mechanism: a monoclonal antibody that binds CD38 on plasma cells and other immune cells, leading to their depletion or functional silencing.
• Key data: in the IGNAZ phase 2 study, felzartamab produced rapid and clinically meaningful reductions in proteinuria compared with placebo, with less eGFR decline. Reductions in total IgA and Gd-IgA1 were sustained for well over a year after the last dose, while IgG levels recovered more quickly.
• Status: still investigational. In addition to the IGNAZ phase 2 study, a phase 3 PREVAIL study is recruiting in Japan. Longer-term and larger studies are still needed, but the durability of response raises the possibility of disease modification.

Mezagitamab (TAK-079, anti-CD38 monoclonal antibody)

• Mechanism: another anti-CD38 antibody that depletes or functionally suppresses CD38-expressing cells, aiming to reduce production of Gd-IgA1 and other pathogenic antibodies.
• Key data: in a phase 1b IgA nephropathy study, mezagitamab led to ~55% mean reduction in proteinuria and ~50% reduction in Gd-IgA1, with stable eGFR up to 18 months after the last dose. Hematuria resolved in many patients, and IgG levels recovered toward normal while disease-driving markers stayed suppressed.
• Status: a phase 3 program is underway; the early data support the idea that a time-limited course could have long-lasting effects.

CM313 (anti-CD38 monoclonal antibody)

• Mechanism: a subcutaneous CD38-targeting biologic intended to reduce disease-driving antibody production by targeting CD38-expressing immune cells.
• Key data: a phase 2 study is evaluating safety, efficacy, pharmacokinetics, pharmacodynamics, and immunogenicity in adults with primary IgA nephropathy.
• Status: a phase 2 study is listed but not yet recruiting; not approved for IgA nephropathy.

Instead of broadly suppressing the immune system, these agents use newer mechanism-specific strategies. Some are designed to remove or break down disease-driving IgA directly, while others aim to change kidney inflammation, fibrosis, or metabolic stress through different pathways.

ARGX-121 (anti-IgA program)

• Mechanism: an investigational antibody program intended to target disease-driving IgA. Public materials do not yet provide enough detail to describe its mechanism more specifically.
• Key data: no patient efficacy data have been publicly reported.
• Status: argenx is advancing a phase 2 randomized study in primary IgA nephropathy. The registry lists the study as not yet recruiting; it is not approved for IgA nephropathy.

Several newer phase 2 programs are also listed in trial registries even though their sponsors have not publicly described enough mechanism or efficacy data to place them more precisely in the categories above.

Civorebrutinib (EVER001; XNW1011; reversible BTK inhibitor)

• Mechanism: a next-generation covalent reversible Bruton's tyrosine kinase (BTK) inhibitor intended to modulate B-cell receptor signaling and other immune pathways without directly depleting B cells.
• Key data: early clinical data have been reported in primary membranous nephropathy, but no patient efficacy data in IgA nephropathy have been publicly reported.
• Status: a phase 1b/2 open-label study in China includes an IgA nephropathy cohort. Civorebrutinib is not approved for IgA nephropathy.

STL303 (Sitala Bio)

• Key data: no patient efficacy data or detailed public mechanism information were identified in the current trial record.
• Status: an oral, randomized phase IIb study is registered in primary IgA nephropathy, with approximately 15 participants planned. The study is listed as not yet recruiting, and STL303 is not approved for IgA nephropathy.

FXS6837 (Fosun Pharma)

• Key data: no patient efficacy data or sufficiently detailed public mechanism information were identified in the current trial record.
• Status: a randomized phase IIb oral study is registered for primary IgA nephropathy and is listed as not yet recruiting. FXS6837 is not approved for IgA nephropathy.

SHR-2173 (Hengrui)

• Key data: no patient efficacy data or sufficiently detailed public mechanism information were identified in the current trial record.
• Status: a randomized phase II study of SHR-2173 injection is recruiting in China. It is not approved for IgA nephropathy.

BHV-1400 (Gd-IgA1 TRAP degrader)

• Mechanism: a "TRAP degrader" designed to bind Gd-IgA1 in the bloodstream and route it to the liver for clearance, while sparing normal immunoglobulins (IgA, IgG, IgE, IgM). This is a precision approach aimed at the root antibody driver of IgA nephropathy and IgA vasculitis.
• Key data: phase 1 and phase 1b data showed rapid, deep, and selective reductions in Gd-IgA1 while sparing other immunoglobulins. In early IgA nephropathy patient data, Biohaven reported mean Gd-IgA1 reductions of more than 60% within 48 hours and about 70% within one month, with preliminary associated changes in hematuria, spot UPCR, and eGFR. These patient data remain early and limited.
• Status: a phase 1 biomarker study in IgA nephropathy is recruiting, and a phase 3 study is listed but not yet recruiting. It is not approved for IgA nephropathy.

AP308 (engineered recombinant IgA protease)

• Mechanism: an engineered recombinant IgA protease designed to break down IgA directly, a different strategy from suppressing IgA production or blocking downstream complement activation.
• Key data: Alebund describes AP308 as a first-in-class IgA protease program aiming for a functional cure of IgA nephropathy.
• Status: the FDA cleared Alebund's IND application in September 2026. The program has not yet reported a first-in-human IgA nephropathy study or human efficacy data, and AP308 is not approved for IgA nephropathy.

AP303 (dual PPAR agonist)

• Mechanism: a dual PPAR agonist being developed to delay or halt chronic kidney disease progression across potential indications including diabetic kidney disease and IgA nephropathy.
• Key data: phase 1 studies in Australia and China showed favorable safety and tolerability in healthy volunteers and patients with diabetic kidney disease, with a dose-dependent pharmacodynamic signal. IgA nephropathy efficacy data are not yet available.
• Status: IND cleared by the U.S. FDA and China's NMPA; Alebund expects to conduct a basket phase 2 trial in diabetic kidney disease and IgA nephropathy patients in the second half of 2026. It is not approved for IgA nephropathy.

These approaches try to protect or repair kidney tissue, re-program kidney cells, or alter immune pathways at a genetic level, with the goal of more durable disease control. They are much earlier in development than the approved medicines above, and early safety or biomarker findings should not be mistaken for proof that they can regenerate nephrons or reverse established kidney scarring.

ADR-001 (allogeneic adipose-derived mesenchymal stem-cell therapy)

• Mechanism: an intravenous cell therapy intended to provide immunomodulatory and paracrine effects that may reduce kidney injury and support tissue repair.
• Key data: a phase 1, open-label dose-escalation study enrolled nine adults with refractory IgA nephropathy. No severe adverse events were observed, and the primary safety and tolerability endpoints were met. Changes in urinary protein and kidney-injury markers were exploratory; the small, uncontrolled study could not establish efficacy or show that ADR-001 reverses fibrosis or regenerates nephron tissue.
• Status: the study was completed in Japan. ADR-001 is not approved for IgA nephropathy, and its role remains experimental.

PS-002 (AAV-based gene therapy delivering complement factor I)

• Mechanism: an adeno-associated virus (AAV) gene therapy that delivers the gene for complement factor I directly to podocytes (specialized kidney cells). By boosting local factor I, the therapy is intended to dampen complement activation in the glomerulus and protect the kidney from ongoing damage.
• Preclinical data: in animal models of IgA nephropathy, PS-002 reduced complement deposition, lowered markers of kidney injury, and improved structural features such as scarring, with sustained gene expression and favorable safety.
• Status: a phase I/II clinical trial in adults with primary IgA nephropathy has received regulatory clearance and is now enrolling, but human efficacy data in IgA nephropathy are not yet available.

WAL0921 (investigational therapy for proteinuric glomerular kidney diseases)

• Mechanism: an investigational intravenous therapy being studied across several proteinuric glomerular kidney diseases, including primary IgA nephropathy.
• Key data: a phase 2 basket study is evaluating safety, pharmacokinetics, pharmacodynamics, albuminuria, proteinuria, and eGFR measures in diabetic nephropathy and rare glomerular kidney diseases.
• Status: phase 2 trial recruiting; not approved for IgA nephropathy.