Angiotensin II Antagonist in Severe Sepsis

Phase III Study of Irbersartan for the Early Treatment of Severe Sepsis Patients

The investigators propose a clinical study of irbersartan for the early treatment of severe sepsis patients with elevated predicted risk of death between. This study will evaluate whether early administration of the the angiotensin receptor blocker irbersartan provides significant reduction of 28 days mortality and multi organ failure incidence to patients with severe sepsis.

Background: Angiotensin II (ANG II) is a potent vasoconstrictor and diminishes vasodilator responses in arteries. In addition to direct effects on vascular tone, ANG II affects multiple aspects of microvascular function through promotion of leukostasis, induction of capillary permeability and depletion of glutathione. Binding of ANG II to its receptors (in particular AT1) mediates intracellular free radical generation that contributes to tissue damage by promoting mitochondrial dysfunction.

Angiotensin receptor blockers (ARBs) interrupt renin-angiotensin system (RAS) overactivity by blocking a specific receptor that mediates the pathogenic activity of angiotensin II. Objectives: The clinical question objective of this study is if the antiinflammatory effect of ARBs is relevant in sepsis management and in particular if ARBs are able to improve survival and reduce the incidence of Multi Organ Failure in septic patients.

Methods:

STUDY DESIGN: Experimental; prospective, randomized, multicenter, phase III trial.

STUDY POPULATION: Three hundred adults within 12 hrs of recognition of severe sepsis, with Acute Physiology and Chronic Health Evaluation (APACHE) II-predicted risk of mortality between 20% and 80% are eligible.

Settings: 5 Italian Intensive Care Units. Oral irbesartan (total dose of 75 mg) or placebo administered every 24 hrs for 15 days. Analysis of data performed by a blind operator. Expected results: about 25% reduction in 28-day mortality rate and incidence of multi organ failure in the study population.

Inclusion Criteria: adults within 12 hrs of recognition of severe sepsis, with Acute Physiology and Chronic Health Evaluation (APACHE) II-predicted risk of mortality between 20% and 80% are eligible.

Exclusion Criteria:Patients already treated with ACE inhibitors or ARBs will be excluded. Patients admitted in shock conditions (systolic blood pressure lower than 90 mmHg) will be excluded. Patients with severe renal failure (serum creatinine of 2.0 mg/dL or dialysis) will be excluded.