Background/Aims: The aim of this post-hoc analysis of a prospective study in patients with type 2 diabetic nephropathy was to investigate whether treatment with the angiotensin II type 1 receptor blocker irbesartan leads to a reduction in the serum levels of the advanced glycation end products (AGEs) pentosidine and NΕ-carboxymethyllysine (CML). Methods: One hundred and ninety-six patients of the Irbesartan in Diabetic Nephropathy Trial cohort (mean age 61 ± 6.5 years, 62 female, 134 male) with a mean estimated glomerular filtration rate of 47.7 ml/min were treated with irbesartan (n = 65), the calcium channel blocker amlodipine (n = 61) or by placebo (n = 70). Serum levels of pentosidine and CML were measured at baseline and after follow-up (23.4 months). Results: Estimated glomerular filtration rate decreased in all groups by a mean of 8.6 ml/min. Serum levels of AGEs increased significantly (p < 0.001) during follow-up. After controlling for renal function and total protein concentration, changes were 53, 55, 50% for pentosidine and 29, 24, 23% for CML (irbesartan, amlodipine and placebo group, respectively). The increase was not significantly different between the treatment groups. Conclusion: Irbesartan did not alter the increase in pentosidine and CML in serum of type 2 diabetic patients with progressive nephropathy. This finding suggests that angiotensin receptor blockade alone is insufficient to reduce serum levels of AGEs in diabetic nephropathy.