Background: In autosomal dominant polycystic kidney disease (ADPKD) there is an unmet need for early markers of rapid disease progression to facilitate counseling and selection for kidney-protective therapy. Our aim was to identify markers for rapid disease progression in urinary extracellular vesicles (uEVs). Methods: uEVs were isolated at baseline in two independent cohorts including patients with rapid disease progression and stable disease; patients were matched by age, sex, total kidney volume and mutation. uEV biomarker candidates were identified by mass spectrometry and further analyzed in a third and fourth cohort using immunoblotting and an enzyme-linked immunosorbent assay (ELISA). Single-nucleotide RNA sequencing of healthy and ADPKD tissue was used to confirm findings and identify the cellular origin of the uEV biomarker. Results: In the first two cohorts matrix metalloproteinase-7 (MMP-7) was significantly higher in uEVs of patients with rapid disease progression compared to stable disease. In the third cohort, immunoblotting confirmed a >2-fold increase in uEV-MMP-7 in patients with rapid disease progression compared to stable disease. In the fourth cohort, whole urine rather than uEVs were analyzed with MMP-7 ELISA demonstrating a significant but weak correlation with kidney function decline. Single-nucleotide RNA sequencing showed higher MMP-7 expression in ADPKD kidney tissue than in healthy kidney tissue and localized MMP-7 to the proximal tubule and thick ascending limb. Conclusion: uEV-associated MMP-7 is elevated in ADPKD patients with rapid disease progression and should be further investigated as predictive biomarker. Our findings also suggests that MMP-7 performs better when analyzed in uEVs than in whole urine.