ALIGN Trial Explained: Atrasentan (Vanrafia) for IgA Nephropathy | Landmark Trials in Nephrology

ALIGN closes the modern IgA nephropathy toolkit. Five years ago, IgAN had no approved disease-specific therapy. Today nephrologists have three: Nefecon (NefIgArd, gut-localized B-cell suppression), sparsentan (PROTECT, dual endothelin-angiotensin antagonist), and now atrasentan (ALIGN, selective endothelin A antagonist). Three different mechanisms. Three different patient profiles. Real choice for tailored therapy. This video breaks down the trial in the NEJM QuickTake format — the trilogy completion narrative, the endothelin A vs B receptor biology that makes selective blockade attractive, the active-controlled design (atrasentan added on top of background RAS blockade), the Week 36 proteinuria result that won FDA accelerated approval, the safety profile, the critical "no REMS program required" prescribing advantage over sparsentan, limitations, and a three-way decision framework for choosing between Nefecon, sparsentan, and atrasentan in practice. KEY DIFFERENTIATOR: atrasentan is approximately 1,000× more selective for endothelin A over endothelin B receptors. This means it blocks the harmful receptor while preserving the protective one. In practice, this translates to a clean safety profile: no boxed warning for hepatotoxicity, no Risk Evaluation and Mitigation Strategy program, standard prescribing. Third GN trial in the IgAN arc, completing the trilogy with NefIgArd and PROTECT. 📋 CHAPTERS 00:00 Introduction 00:22 The IgA Nephropathy Toolkit Is Complete 01:42 Why Selective ETA Blockade Matters (ETA vs ETB Biology) 03:07 Study Design 05:11 Week 36: The Primary Endpoint Result 07:10 Safety: A Cleaner Profile Than Expected 08:28 The Practical Advantage: NO REMS Program 09:58 Board Pearl 11:50 Honest Limitations 13:01 Choosing Between Nefecon, Sparsentan, and Atrasentan 14:51 Where IgA Nephropathy Stands in 2026 16:18 One-Sentence Summary and Closing 🔑 KEY NUMBERS N = 340 enrolled, 270 in main stratum (primary efficacy analysis) Phase 3, multinational, double-blind, placebo-controlled (NCT04573478) Inclusion: biopsy-proven primary IgAN, eGFR ≥ 30, proteinuria ≥ 1 g/day, on max-tolerated ACEi/ARB ≥ 12 weeks Atrasentan 0.75 mg orally once daily ADDED on top of background RAS blockade (NOT a replacement) 132 weeks of double-blind treatment Week 36 primary endpoint: 24-h UPCR change −38.1% atrasentan vs −3.1% placebo Treatment difference: 36.1 percentage points (P less than 0.001) Effect onset: significant by Week 6 FDA accelerated approval: April 2, 2025 (Vanrafia) Indication threshold: UPCR ≥ 1.5 g/g (rapid disease progression) Confirmatory eGFR data (Week 136) expected 2026 → traditional approval 🎯 SAFETY HIGHLIGHTS Treatment-emergent AEs: 82.2% atrasentan vs 84.7% placebo (balanced) Serious AEs: 5.9% vs 6.5% (numerically lower with atrasentan) Drug discontinuations: 3.6% vs 3.5% (identical) Fluid retention: 11.2% vs 8.2% (mechanism-expected) Anemia (hemodilution): 8.3% vs 2.4% (mechanism-expected) NO hepatotoxicity boxed warning NO REMS program required ← the major prescribing advantage ⚠️ CRITICAL CLINICAL PEARL Atrasentan is added ON TOP of an angiotensin receptor blocker — it does NOT replace it. This is a key distinction from sparsentan (which contains an ARB component within its molecular structure and replaces the patient's existing ARB). 📚 REFERENCE Heerspink HJL, Jardine M, Kohan DE, et al. Atrasentan in Patients with IgA Nephropathy. N Engl J Med 2025; 392: 544-554. https://www.nejm.org/doi/full/10.1056... 📖 KDIGO 2025 IgA Nephropathy Guideline https://kdigo.org/guidelines/gd/ 🎓 LANDMARK TRIALS PLAYLIST ▶ CREDENCE: ▶ FIDELIO-DKD: ▶ FLOW: ▶ STARRT-AKI: ▶ AKIKI-2: ▶ EMPA-KIDNEY: ▶ DAPA-CKD: ▶ MENTOR: ▶ NefIgArd: ▶ PROTECT: ▶ ALIGN: 👨‍⚕️ ABOUT Dr. Amit Kaushal, MD, FASN is Assistant Professor of Medicine and Medical Director of Dialysis Units in the Division of Nephrology & Hypertension at West Virginia University School of Medicine. 🔔 SUBSCRIBE for new landmark trial breakdowns — designed for nephrology fellows, IM residents, and practicing nephrologists who want the evidence without the 40-page read. 📧 For patient-facing kidney health content, check out my Substack: Kidney Health Explained https://kidneyhealthexplained.substac... #ALIGN #Atrasentan #Vanrafia #IgANephropathy #IgAN #EndothelinAntagonist #Nephrology #GlomerularDisease #BoardReview #KDIGO2025 #LandmarkTrials