Neuropilins, relevant targets for the treatment of clear cell Renal Cell Carcinoma

Les cancers du rein à cellules claires (ccRCC) représentent 80% des cancers du rein. Environ 80% des ccRCC présentent une inactivation/ mutation du gène de Von Hippel-Lindau (VHL), entraînant la stabilisation des facteurs inductibles d'hypoxie 1 et 2 alpha (HIF1 et 2α) et la surexpression de leurs gènes cibles tels que "le facteur de croissance vasculaire endothélial (VEGF)", le principal facteur d'angiogenèse. Ainsi les ccRCC sont les cancers les plus vascularisés et représentent un paradigme pour les traitements anti-angiogéniques (AAT). Aujourd'hui, 15 différents AAT ont obtenu l'approbation de la FDA et de l'EMA. Ils sont divisés en trois familles :- les anticorps ciblant les VEGFs- les inhibiteurs de tyrosine-kinase (TKi), qui ciblent les récepteurs impliqués dans la néo-angiogenèse, tel que le sunitinib- les récepteurs « leurres » qui piègent le VEGFA et le PlGF tel que l’aflibercept.La surexpression du VEGF (impliqué dans l'angiogenèse), et des autres membres de la famille du VEGF, le VEGFC (impliqué dans la lymphangiogenèse) est un phénomène clé dans la tolérance immune. Ainsi, des inhibiteurs de points de contrôle immunitaire (anti PD-1, anti PD-L1 et anti CTLA-4) ont aussi obtenu l'approbation des autorités de santé pour le traitement des ccRCC.En revanche, une rechute après quelques mois de traitement par les TKi est souvent observée et les inhibiteurs de points de contrôle immunitaire présentent une efficacité sur seulement 20% des patients. Ainsi, le ccRCC reste incurable chez une majorité de patients et de nouvelles stratégies thérapeutiques ciblant à la fois l'angiogenèse, la lymphangiogenèse et la tolérance immune sont nécessaires.Les Neuropilines (NRP1 et NRP2) sont des corécepteurs de VEGF et de VEGFC et sont exprimés sur les cellules endothéliales vasculaires et lymphatiques, sur les cellules tumorales et sur les cellules du système immunitaire. Ainsi, les Neuropilines sont de nouvelles cibles pertinentes pour le traitement du ccRCC.Ma thèse décrit la pertinence du ciblage des voies de signalisation NRP1 et NRP2 dans les ccRCC par une approche génétique (invalidation des deux gènes par CRISPR/Cas9) et par une approche pharmacologique (développement d’un inhibiteur des NRPs). Les résultats précliniques générés représentent une première étape essentielle pour l’initiation d’essais cliniques de phase précoce pour les patients en échec thérapeutique.Clear cell Renal Cell Carcinoma (ccRCC) represent 80% of kidney cancers. Around 80% of ccRCC present an inactivation of the von Hippel-Lindau gene (VHL) gene, leading to the stabilization the Hypoxia Inducible Factors 1 and 2 alpha (HIF-1 and 2α) and to the overexpression of their targeted genes such as the « Vascular Endothelial Growth Factor (VEGF) », the principal angiogenic factor. Thus, ccRCC are one of the most vascularized cancers and represent a paradigm for anti-angiogenic treatments (AAT). Currently,15 different AAT have obtained FDA and EMA approval. They are divided in three different families:- antibodies targeting VEGF- tyrosine-kinase inhibitors (TKi) that target receptors involved in neo-angiogenesis such as the current reference therapy, sunitinib- decoy receptors that trap VEGFA and PlGF such as aflibercept.Overexpression of VEGF (involved in angiogenesis) and of the other member of the VEGF family, VEGFC (involved in lymphangiogenesis) is also a key phenomenon of immune tolerance. Therefore, immune-checkpoint inhibitors (anti PD-1, anti PD-L1 and anti CTLA-4) also obtained an approval for the treatment of ccRCC.However, relapse on TKi are frequently observed after a few months and immune-checkpoint inhibitors present a long-lasting effect only in 20% of patients. Hence, ccRCC is still an uncurable disease and new therapeutic strategies targeting concomitantly angiogenesis/lymphangiogenesis and immune tolerance are urgently needed. Neuropilins (NRP1 and NRP2) are co-receptors of VEGF and VEGFC and are expressed on vascular and lymphatic endothelial cells, on tumor cells and on immune cells. Hence, they may represent ideal targets to inhibit the drivers of ccRCC aggressiveness.My thesis describes the relevance of targeting the NRP1 and NRP2 signaling pathways in ccRCC by a genetic (invalidation of the two genes by CRISPR/Cas9) and by a pharmacological approach (development of a NRPs inhibitor). The preclinical results generated represent an essential first step for the initiation of early phase clinical trials for patients with treatment failure

Les Neuropilines, des cibles pertinentes dans le traitement du cancer du rein à cellules claires

Clear cell Renal Cell Carcinoma (ccRCC) represent 80% of kidney cancers. Around 80% of ccRCC present an inactivation of the von Hippel-Lindau gene (VHL) gene, leading to the stabilization the Hypoxia Inducible Factors 1 and 2 alpha (HIF-1 and 2α) and to the overexpression of their targeted genes such as the « Vascular Endothelial Growth Factor (VEGF) », the principal angiogenic factor. Thus, ccRCC are one of the most vascularized cancers and represent a paradigm for anti-angiogenic treatments (AAT). Currently,15 different AAT have obtained FDA and EMA approval. They are divided in three different families:-antibodies targeting VEGF-tyrosine-kinase inhibitors (TKi) that target receptors involved in neo-angiogenesis such as the current reference therapy, sunitinib- decoy receptors that trap VEGFA and PlGF such as aflibercept.Overexpression of VEGF (involved in angiogenesis) and of the other member of the VEGF family, VEGFC (involved in lymphangiogenesis) is also a key phenomenon of immune tolerance. Therefore, immune-checkpoint inhibitors (anti PD-1, anti PD-L1 and anti CTLA-4) also obtained an approval for the treatment of ccRCC.However, relapse on TKi are frequently observed after a few months and immune-checkpoint inhibitors present a long-lasting effect only in 20% of patients. Hence, ccRCC is still an uncurable disease and new therapeutic strategies targeting concomitantly angiogenesis/lymphangiogenesis and immune tolerance are urgently needed. Neuropilins (NRP1 and NRP2) are co-receptors of VEGF and VEGFC and are expressed on vascular and lymphatic endothelial cells, on tumor cells and on immune cells. Hence, they may represent ideal targets to inhibit the drivers of ccRCC aggressiveness.My thesis describes the relevance of targeting the NRP1 and NRP2 signaling pathways in ccRCC by a genetic (invalidation of the two genes by CRISPR/Cas9) and by a pharmacological approach (development of a NRPs inhibitor). The preclinical results generated represent an essential first step for the initiation of early phase clinical trials for patients with treatment failure.Les cancers du rein à cellules claires (ccRCC) représentent 80% des cancers du rein. Environ 80% des ccRCC présentent une inactivation/ mutation du gène de Von Hippel-Lindau (VHL), entraînant la stabilisation des facteurs inductibles d'hypoxie 1 et 2 alpha (HIF1 et 2α) et la surexpression de leurs gènes cibles tels que "le facteur de croissance vasculaire endothélial (VEGF)", le principal facteur d'angiogenèse. Ainsi les ccRCC sont les cancers les plus vascularisés et représentent un paradigme pour les traitements anti-angiogéniques (AAT). Aujourd'hui, 15 différents AAT ont obtenu l'approbation de la FDA et de l'EMA. Ils sont divisés en trois familles :- les anticorps ciblant les VEGFs- les inhibiteurs de tyrosine-kinase (TKi), qui ciblent les récepteurs impliqués dans la néo-angiogenèse, tel que le sunitinib- les récepteurs « leurres » qui piègent le VEGFA et le PlGF tel que l’aflibercept.La surexpression du VEGF (impliqué dans l'angiogenèse), et des autres membres de la famille du VEGF, le VEGFC (impliqué dans la lymphangiogenèse) est un phénomène clé dans la tolérance immune. Ainsi, des inhibiteurs de points de contrôle immunitaire (anti PD-1, anti PD-L1 et anti CTLA-4) ont aussi obtenu l'approbation des autorités de santé pour le traitement des ccRCC.En revanche, une rechute après quelques mois de traitement par les TKi est souvent observée et les inhibiteurs de points de contrôle immunitaire présentent une efficacité sur seulement 20% des patients. Ainsi, le ccRCC reste incurable chez une majorité de patients et de nouvelles stratégies thérapeutiques ciblant à la fois l'angiogenèse, la lymphangiogenèse et la tolérance immune sont nécessaires.Les Neuropilines (NRP1 et NRP2) sont des corécepteurs de VEGF et de VEGFC et sont exprimés sur les cellules endothéliales vasculaires et lymphatiques, sur les cellules tumorales et sur les cellules du système immunitaire. Ainsi, les Neuropilines sont de nouvelles cibles pertinentes pour le traitement du ccRCC.Ma thèse décrit la pertinence du ciblage des voies de signalisation NRP1 et NRP2 dans les ccRCC par une approche génétique (invalidation des deux gènes par CRISPR/Cas9) et par une approche pharmacologique (développement d’un inhibiteur des NRPs). Les résultats précliniques générés représentent une première étape essentielle pour l’initiation d’essais cliniques de phase précoce pour les patients en échec thérapeutique

Les neuropilines: Des cibles pertinentes pour améliorer le traitement des cancers

International audienceUne angiogenèse exacerbée est une des caractéristiques (« hallmarks ») du cancer, définies par Hanahan et Weinberg1. Cependant, le ciblage de la voie de signalisation du VEGF (vascular endothelial growth factor) ou de ses récepteurs a montré ses limites thérapeutiques. Après un bénéfice thérapeutique indéniable pour les patients, les tumeurs récidivent après quelques mois, et deviennent généralement métastatiques et incurables. Les neuropilines 1 et 2 (NRP1, 2) dont l’activité a été décrite initialement dans le système nerveux, stimulent de nombreuses fonctions impliquées dans l’agressivité tumorale, notamment la prolifération cellulaire, l’angiogenèse et la lymphangiogenèse, ainsi que la tolérance immunitaire. Ainsi, une surexpression de NRP1 ou 2 dans de nombreuses tumeurs, est corrélée à une survie courte des patients. Cette revue a pour objectif de décrire les mécanismes d’action impliqués dans la stimulation de NRP1 et NRP2 et de faire le point sur les stratégies thérapeutiques en études précliniques ou en essais de phase précoces chez des patients atteints de différents cancers

Myokines: Crosstalk and Consequences on Liver Physiopathology

Non-alcoholic fatty liver disease (NAFLD) is a chronic liver disease mainly characterized by the hepatic accumulation of lipid inducing a deregulation of β-oxidation. Its advanced form is non-alcoholic steatohepatitis (NASH), which, in addition to lipid accumulation, induces hepatocellular damage, oxidative stress and fibrosis that can progress to cirrhosis and to its final stage: hepatocellular carcinoma (HCC). To date, no specific therapeutic treatment exists. The implications of organ crosstalk have been highlighted in many metabolic disorders, such as diabetes, metabolic-associated liver diseases and obesity. Skeletal muscle, in addition to its role as a reservoir and consumer of energy and carbohydrate metabolism, is involved in this inter-organs’ communication through different secreted products: myokines, exosomes and enzymes, for example. Interestingly, resistance exercise has been shown to have a beneficial impact on different metabolic pathways, such as lipid oxidation in different organs through their secreted products. In this review, we will mainly focus on myokines and their effects on non-alcoholic fatty liver disease, and their complication: non-alcoholic steatohepatitis and HCC

Anti-Vascular Endothelial Growth Factor C Antibodies Efficiently Inhibit the Growth of Experimental Clear Cell Renal Cell Carcinomas

Despite improvement during the last ten years in the longevity of patients with metastatic clear cell renal cell carcinoma (mccRCC) the disease remains incurable. Hence, new therapeutic strategies are urgently needed. Relapse following anti-angiogenic treatment depends on the over-expression of vascular endothelial growth factor C (VEGFC), one of the main drivers of lymphangiogenesis. Therefore, we developed specific mouse monoclonal antibodies and evaluated their therapeutic efficacy in vitro and in vivo. Immunization of mice with the domain of VEGFC that stimulates the VEGF receptor 3 (VEGFR3) led to the selection of one hybridoma producing specific anti-VEGFC monoclonal antibodies. The selected 1E9 antibodies were sequenced, and the corresponding variable light and heavy chains were subcloned into expression vectors in frame with sequences encoding the human IgG1 constant heavy and light chains. CHO cells were stably transfected and cloned to produce chimeric antibodies. These antibodies inhibited the activation of VEGFR3 signaling, and therefore the proliferation and migration of VEGFC-stimulated endothelial cells. Moreover, they inhibited the proliferation of VEGFC-expressing renal cancer cells through NRP2 signaling. 1E9 antibodies inhibited the growth of experimental RCC, and their therapeutic efficacy was enhanced by the anti-VEGF antibody bevacizumab. Hence, our results suggest that targeting VEGFC could have a relevant therapeutic impact on mccRCC that relapse following anti-angiogenic treatment

Neuropilin 1 and Neuropilin 2 gene invalidation or pharmacological inhibition reveals their relevance for the treatment of metastatic renal cell carcinoma

International audienceBackground: Despite the improvement of relapse-free survival mediated by anti-angiogenic drugs like sunitinib (Sutent®), or by combinations of anti-angiogenic drugs with immunotherapy, metastatic clear cell Renal Cell Carcinoma (mccRCC) remain incurable. Hence, new relevant treatments are urgently needed. The VEGFs coreceptors, Neuropilins 1, 2 (NRP1, 2) are expressed on several tumor cells including ccRCC. We analyzed the role of the VEGFs/NRPs signaling in ccRCC aggressiveness and evaluated the relevance to target this pathway.Methods: We correlated the NRP1, 2 levels to patients’ survival using online available data base. Human and mouse ccRCC cells were knocked-out for the NRP1 and NRP2 genes by a CRISPR/Cas9 method. The number of metabolically active cells was evaluated by XTT assays. Migration ability was determined by wound closure experiments and invasion ability by using Boyden chamber coated with collagen. Production of VEGFA and VEGFC was evaluated by ELISA. Experimental ccRCC were generated in immuno-competent/deficient mice. The effects of a competitive inhibitor of NRP1, 2, NRPa-308, was tested in vitro and in vivo with the above-mentioned tests and on experimental ccRCC. NRPa-308 docking was performed on both NRPs.Results: Knock-out of the NRP1 and NRP2 genes inhibited cell metabolism and migration and stimulated the expression of VEGFA or VEGFC, respectively. NRPa-308 presented a higher affinity for NRP2 than for NRP1. It decreased cell metabolism and migration/invasion more efficiently than sunitinib and the commercially available NRP inhibitor EG00229. NRPa-308 presented a robust inhibition of experimental ccRCC growth in immunocompetent and immunodeficient mice. Such inhibition was associated with decreased expression of several pro-tumoral factors. Analysis of the TCGA database showed that the NRP2 pathway, more than the NRP1 pathway correlates with tumor aggressiveness only in metastatic patients.Conclusions: Our study strongly suggests that inhibiting NRPs is a relevant treatment for mccRCC patients in therapeutic impasses and NRPa-308 represents a relevant hit

Synthesis, 3D-structure and stability analyses of NRPa-308, a new promising anti-cancer agent

International audienceWe report herein the synthesis of a newly described anti-cancer agent, NRPa-308. This compound antagonizes Neuropilin-1, a multi-partners transmembrane receptor overexpressed in numerous tumors, and thereby validated as promising target in oncology. The preparation of NRPa-308 proved challenging because of the ortho-gonality of the amide and sulphonamide bonds formation. Nevertheless, we succeeded a gram scale synthesis, according to an expeditious three steps route, without intermediate purification. This latter point is of utmost interest in reducing the ecologic impact and production costs in the perspective of further scale-up processes. The purity of NRPa-308 has been attested by means of conventional structural analyses and its crystallisation allowed a structural assessment by X-Ray diffraction. We also reported the remarkable chemical stability of this molecule in acidic, neutral and basic aqueous media. Eventually, we observed for the first time the accumulation of NRPa-308 in two types of human breast cancer cells MDA-MB231 and BT549. Tumor neoangiogenesis supplies cancer cells in oxygen and nutrients. Moreover, the neoformed blood vessels promote also the dissemination of malignant cells to healthy tissues. Therefore, tackling angiogenesis proved to be a relevant therapeutic option in oncology since more than 30 years

Efficacy and safety of sparsentan versus irbesartan in patients with IgA nephropathy (PROTECT): 2-year results from a randomised, active-controlled, phase 3 trial

BackgroundSparsentan, a novel, non-immunosuppressive, single-molecule, dual endothelin angiotensin receptor antagonist, significantly reduced proteinuria versus irbesartan, an angiotensin II receptor blocker, at 36 weeks (primary endpoint) in patients with immunoglobulin A nephropathy in the phase 3 PROTECT trial's previously reported interim analysis. Here, we report kidney function and outcomes over 110 weeks from the double-blind final analysis.MethodsPROTECT, a double-blind, randomised, active-controlled, phase 3 study, was done across 134 clinical practice sites in 18 countries throughout the Americas, Asia, and Europe. Patients aged 18 years or older with biopsy-proven primary IgA nephropathy and proteinuria of at least 1·0 g per day despite maximised renin–angiotensin system inhibition for at least 12 weeks were randomly assigned (1:1) to receive sparsentan (target dose 400 mg oral sparsentan once daily) or irbesartan (target dose 300 mg oral irbesartan once daily) based on a permuted-block randomisation method. The primary endpoint was proteinuria change between treatment groups at 36 weeks. Secondary endpoints included rate of change (slope) of the estimated glomerular filtration rate (eGFR), changes in proteinuria, a composite of kidney failure (confirmed 40% eGFR reduction, end-stage kidney disease, or all-cause mortality), and safety and tolerability up to 110 weeks from randomisation. Secondary efficacy outcomes were assessed in the full analysis set and safety was assessed in the safety set, both of which were defined as all patients who were randomly assigned and received at least one dose of randomly assigned study drug. This trial is registered with ClinicalTrials.gov, NCT03762850.FindingsBetween Dec 20, 2018, and May 26, 2021, 203 patients were randomly assigned to the sparsentan group and 203 to the irbesartan group. One patient from each group did not receive the study drug and was excluded from the efficacy and safety analyses (282 [70%] of 404 included patients were male and 272 [67%] were White) . Patients in the sparsentan group had a slower rate of eGFR decline than those in the irbesartan group. eGFR chronic 2-year slope (weeks 6–110) was −2·7 mL/min per 1·73 m2 per year versus −3·8 mL/min per 1·73 m2 per year (difference 1·1 mL/min per 1·73 m2 per year, 95% CI 0·1 to 2·1; p=0·037); total 2-year slope (day 1–week 110) was −2·9 mL/min per 1·73 m2 per year versus −3·9 mL/min per 1·73 m2 per year (difference 1·0 mL/min per 1·73 m2 per year, 95% CI −0·03 to 1·94; p=0·058). The significant reduction in proteinuria at 36 weeks with sparsentan was maintained throughout the study period; at 110 weeks, proteinuria, as determined by the change from baseline in urine protein-to-creatinine ratio, was 40% lower in the sparsentan group than in the irbesartan group (−42·8%, 95% CI −49·8 to −35·0, with sparsentan versus −4·4%, −15·8 to 8·7, with irbesartan; geometric least-squares mean ratio 0·60, 95% CI 0·50 to 0·72). The composite kidney failure endpoint was reached by 18 (9%) of 202 patients in the sparsentan group versus 26 (13%) of 202 patients in the irbesartan group (relative risk 0·7, 95% CI 0·4 to 1·2). Treatment-emergent adverse events were well balanced between sparsentan and irbesartan, with no new safety signals.InterpretationOver 110 weeks, treatment with sparsentan versus maximally titrated irbesartan in patients with IgA nephropathy resulted in significant reductions in proteinuria and preservation of kidney function

Sparsentan in patients with IgA nephropathy: a prespecified interim analysis from a randomised, double-blind, active-controlled clinical trial

Background: Sparsentan is a novel, non-immunosuppressive, single-molecule, dual endothelin and angiotensin receptor antagonist being examined in an ongoing phase 3 trial in adults with IgA nephropathy. We report the prespecified interim analysis of the primary proteinuria efficacy endpoint, and safety. Methods: PROTECT is an international, randomised, double-blind, active-controlled study, being conducted in 134 clinical practice sites in 18 countries. The study examines sparsentan versus irbesartan in adults (aged ≥18 years) with biopsy-proven IgA nephropathy and proteinuria of 1·0 g/day or higher despite maximised renin-angiotensin system inhibitor treatment for at least 12 weeks. Participants were randomly assigned in a 1:1 ratio to receive sparsentan 400 mg once daily or irbesartan 300 mg once daily, stratified by estimated glomerular filtration rate at screening (30 to 1·75 g/day). The primary efficacy endpoint was change from baseline to week 36 in urine protein-creatinine ratio based on a 24-h urine sample, assessed using mixed model repeated measures. Treatment-emergent adverse events (TEAEs) were safety endpoints. All endpoints were examined in all participants who received at least one dose of randomised treatment. The study is ongoing and is registered with ClinicalTrials.gov, NCT03762850. Findings: Between Dec 20, 2018, and May 26, 2021, 404 participants were randomly assigned to sparsentan (n=202) or irbesartan (n=202) and received treatment. At week 36, the geometric least squares mean percent change from baseline in urine protein-creatinine ratio was statistically significantly greater in the sparsentan group (-49·8%) than the irbesartan group (-15·1%), resulting in a between-group relative reduction of 41% (least squares mean ratio=0·59; 95% CI 0·51-0·69; p<0·0001). TEAEs with sparsentan were similar to irbesartan. There were no cases of severe oedema, heart failure, hepatotoxicity, or oedema-related discontinuations. Bodyweight changes from baseline were not different between the sparsentan and irbesartan groups. Interpretation: Once-daily treatment with sparsentan produced meaningful reduction in proteinuria compared with irbesartan in adults with IgA nephropathy. Safety of sparsentan was similar to irbesartan. Future analyses after completion of the 2-year double-blind period will show whether these beneficial effects translate into a long-term nephroprotective potential of sparsentan. Funding: Travere Therapeutics

Efficacy and safety of sparsentan versus irbesartan in patients with IgA nephropathy (PROTECT): 2-year results from a randomised, active-controlled, phase 3 trial

Background Sparsentan, a novel, non-immunosuppressive, single-molecule, dual endothelin angiotensin receptor antagonist, significantly reduced proteinuria versus irbesartan, an angiotensin II receptor blocker, at 36 weeks (primary endpoint) in patients with immunoglobulin A nephropathy in the phase 3 PROTECT trial's previously reported interim analysis. Here, we report kidney function and outcomes over 110 weeks from the double-blind final analysis. Methods PROTECT, a double-blind, randomised, active-controlled, phase 3 study, was done across 134 clinical practice sites in 18 countries throughout the Americas, Asia, and Europe. Patients aged 18 years or older with biopsy-proven primary IgA nephropathy and proteinuria of at least 1·0 g per day despite maximised renin–angiotensin system inhibition for at least 12 weeks were randomly assigned (1:1) to receive sparsentan (target dose 400 mg oral sparsentan once daily) or irbesartan (target dose 300 mg oral irbesartan once daily) based on a permuted-block randomisation method. The primary endpoint was proteinuria change between treatment groups at 36 weeks. Secondary endpoints included rate of change (slope) of the estimated glomerular filtration rate (eGFR), changes in proteinuria, a composite of kidney failure (confirmed 40% eGFR reduction, end-stage kidney disease, or all-cause mortality), and safety and tolerability up to 110 weeks from randomisation. Secondary efficacy outcomes were assessed in the full analysis set and safety was assessed in the safety set, both of which were defined as all patients who were randomly assigned and received at least one dose of randomly assigned study drug. This trial is registered with ClinicalTrials.gov, NCT03762850. Findings Between Dec 20, 2018, and May 26, 2021, 203 patients were randomly assigned to the sparsentan group and 203 to the irbesartan group. One patient from each group did not receive the study drug and was excluded from the efficacy and safety analyses (282 [70%] of 404 included patients were male and 272 [67%] were White) . Patients in the sparsentan group had a slower rate of eGFR decline than those in the irbesartan group. eGFR chronic 2-year slope (weeks 6–110) was −2·7 mL/min per 1·73 m2 per year versus −3·8 mL/min per 1·73 m2 per year (difference 1·1 mL/min per 1·73 m2 per year, 95% CI 0·1 to 2·1; p=0·037); total 2-year slope (day 1–week 110) was −2·9 mL/min per 1·73 m2 per year versus −3·9 mL/min per 1·73 m2 per year (difference 1·0 mL/min per 1·73 m2 per year, 95% CI −0·03 to 1·94; p=0·058). The significant reduction in proteinuria at 36 weeks with sparsentan was maintained throughout the study period; at 110 weeks, proteinuria, as determined by the change from baseline in urine protein-to-creatinine ratio, was 40% lower in the sparsentan group than in the irbesartan group (−42·8%, 95% CI −49·8 to −35·0, with sparsentan versus −4·4%, −15·8 to 8·7, with irbesartan; geometric least-squares mean ratio 0·60, 95% CI 0·50 to 0·72). The composite kidney failure endpoint was reached by 18 (9%) of 202 patients in the sparsentan group versus 26 (13%) of 202 patients in the irbesartan group (relative risk 0·7, 95% CI 0·4 to 1·2). Treatment-emergent adverse events were well balanced between sparsentan and irbesartan, with no new safety signals. Interpretation Over 110 weeks, treatment with sparsentan versus maximally titrated irbesartan in patients with IgA nephropathy resulted in significant reductions in proteinuria and preservation of kidney function.</p