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.
