From "Broad Screening" to "Mechanism-Based Validation": How ADPKD Kidney Organoid Models Can Truly Empower Drug Development

It All Begins HereExisting organoid models fall into four tiers, each with clear limits. NKO (nephron organoids) are a "broad screening machine," not a "mechanism-based judge": high throughput and low cost, but they lack AVPR2, so tolvaptan shows no effect in them. Collecting duct (CD) organoids are the "gatekeepers of mechanism-based validation"—they express AVPR2 and respond to tolvaptan, but their long preparation time and low throughput make them suitable for secondary screening, not primary screening. Patient-derived MARO answer "genotype–drug efficacy" questions, distinguishing which patients a compound is likely to help, but their throughput fits validation, not discovery. hKPA in vivo transplantation is the "last gate before clinical translation," capturing immune and vascular context absent in vitro, but it is too costly and low-throughput for routine screening.

The most honest conclusion: ADPKD organoids are good enough to help us make decisions, but not good enough to make decisions for us. Each model answers only one question, and drug development failures often occur when a model that answers question A is used to answer question B.