The general aim of this study is to compare telmisartan 80 mg with valsartan 160 mg in hypertensive patients with type 2 diabetes and overt nephropathy with adjusted blood pressure beyond the target of 130/80 mmHg after one year of treatment.

The primary objective of this study is to show that telmisartan 80 mg is at least as effective (i.e., not inferior) and possibly superior to valsartan 160 mg in reducing 24 hour proteinuria after one year of treatment.

This is a randomised, double-blind, double-dummy, forced titration, multicentre, parallel group trial in patients with essential hypertension, diabetes mellitus type 2 and diabetic nephropathy.

After a 4-6 week Run-in period, patients are randomised to one of the treatment groups and receive either Telmisartan 40 - 80 mg or Valsartan 80 - 160 mg. The treatment regimen is a forced titration with the lower dose given for 2 weeks and the higher dose given for the rest of the treatment period summing up to 52 weeks of treatment. During the treatment period, 8 visits to the investigator are scheduled in order to control blood pressure, renal function parameters and safety. In addition, parameters of endothelial function and oxidative stress are measured at baseline, 6 months and after one year of treatment.

Study Hypothesis:

Non-inferiority of telmisartan 80 mg compared to valsartan 160 mg will be tested using the following set of hypotheses:

Null Hypothesis:

The overall mean change from baseline in UPER (24 hour urinary protein excretion rate) for telmisartan 80 mg is inferior to that for valsartan 160 mg by 0.5 g/day or more.

Alternative Hypothesis:

The overall mean change from baseline in UPER (24 hour urinary protein excretion rate) for telmisartan 80 mg is less than 0.5 g/day worse than that for valsartan 160 mg.

Comparison(s):

In order to test the non-inferiority hypothesis, analysis of covariance with treatment and centre as main effects and baseline as a covariate will be performed. Time-to-event data will be analysed using the log-rank test.

Inclusion Criteria:

1. Type 2 diabetes mellitus

2. Aged 30-70 years of age

3. Hypertension at screening defined as:

   • an average cuff systolic blood pressure > 130 mmHg and/or diastolic blood pressure >80 mmHg in untreated patients OR
   • patients receiving antihypertensive therapy (i.e., medications specifically prescribed to treat hypertension)

4. Overt nephropathy defined by 24 hour proteinuria >= 900 mg and by serum creatinine below 265 mol/l (3.0 mg/dl)

Exclusion Criteria: None