Irbesartan

BackgroundIrbesartan, a long acting selective angiotensin-1 receptor inhibitor, in Marfan syndrome might reduce aortic dilatation, which is associated with dissection and rupture. We aimed to determine the effects of irbesartan on the rate of aortic dilatation in children and adults with Marfan syndrome.MethodsWe did a placebo-controlled, double-blind randomised trial at 22 centres in the UK. Individuals aged 6-40 years with clinically confirmed Marfan syndrome were eligible for inclusion. Study participants were all given 75 mg open label irbesartan once daily, then randomly assigned to 150 mg of irbesartan (increased to 300 mg as tolerated) or matching placebo. Aortic diameter was measured by echocardiography at baseline and then annually. All images were analysed by a core laboratory blinded to treatment allocation. The primary endpoint was the rate of aortic root dilatation. This trial is registered with ISRCTN, number ISRCTN90011794.FindingsBetween March 14, 2012, and May 1, 2015, 192 participants were recruited and randomly assigned to irbesartan (n=104) or placebo (n=88), and all were followed for up to 5 years. Median age at recruitment was 18 years (IQR 12-28), 99 (52%) were female, mean blood pressure was 110/65 mm Hg (SDs 16 and 12), and 108 (56%) were taking β blockers. Mean baseline aortic root diameter was 34·4 mm in the irbesartan group (SD 5·8) and placebo group (5·5). The mean rate of aortic root dilatation was 0·53 mm per year (95% CI 0·39 to 0·67) in the irbesartan group compared with 0·74 mm per year (0·60 to 0·89) in the placebo group, with a difference in means of -0·22 mm per year (-0·41 to -0·02, p=0·030). The rate of change in aortic Z score was also reduced by irbesartan (difference in means -0·10 per year, 95% CI -0·19 to -0·01, p=0·035). Irbesartan was well tolerated with no observed differences in rates of serious adverse events.InterpretationIrbesartan is associated with a reduction in the rate of aortic dilatation in children and young adults with Marfan syndrome and could reduce the incidence of aortic complications.FundingBritish Heart Foundation, the UK Marfan Trust, the UK Marfan Association.

The advent of angiotensin II type 1 receptor blockers (ARBs) as intriguing gastroprotective candidates and the superior pharmacokinetics and pharmacodynamics displayed by irbesartan compared to many other ARBs raised the interest to investigate its gastroprotective potential in a rat model of gastric injury. Irbesartan (50 mg/Kg) was orally administered to male Wistar rats once daily for 14 days; thereafter gastric injury was induced by indomethacin (60 mg/Kg, p.o). Irbesartan reduced gastric ulcer index, gastric acidity, and ameliorated indomethacin-induced gastric mucosal apoptotic and inflammatory aberrations, as demonstrated by hampering caspase-3, prostaglandin E2 and tumor necrosis factor-alpha levels and cyclooxygenase-2 mRNA expression. This ARB increased mucosal dimethylarginine dimethylaminohydrolase-1 (DDAH-1) gene expression and decreased elevated levels of matrix metalloproteinase-9, asymmetric dimethylarginine (ADMA), epidermal growth factor receptor (EGFR) mRNA and phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2). Histopathological evaluation corroborated biochemical findings. Overall efficacy of irbesartan was comparable to ranitidine, the widely used H2 receptor blocker. In conclusion, irbesartan exerts significant gastroprotection against indomethacin-induced mucosal damage via acid-inhibitory, anti-inflammatory, anti-apoptotic and extracellular matrix remodeling mechanisms that are probably mediated, at least partly, by down-regulating DDAH/ADMA and EGFR/ERK1/2 signaling.

Hypoxia induces myocardial injury through the activation of inflammatory and oxidative processes. The pivotal role of the renin angiotensin system (RAS) in the pathogenesis of cardiovascular diseases has been firmly established in clinical trials and practice; in fact many experimental and clinical data have highlighted that its inhibition has a cardioprotective role. Activated RAS also stimulates inflammation directly inducing proinflammatory and oxidative gene expression. This study aimed to investigate the protective role of a pre-treatment (10 and 100 μM) with irbesartan on injury induced by 24 h of hypoxia in HL-1 cardiomyocytes; in particular, we have analyzed the natriuretic peptide (BNP) expression, a biomarker able to modulate inflammatory reaction to cardiac injury and some markers involved in oxidative stress and inflammation. Our results demonstrated that a pre-treatment with 100 μM irbesartan significantly increased SOD activity and catalase expression of 15 and 25%, respectively, compared to hypoxic cells (P<0.05). On the other hand, it was able to reduce the release of peroxynitrite and iNOS protein expression of 20 and 50% respectively (P<0.05). In addition irbesartan exerts an anti-inflammatory activity reducing Toll-like receptors (TLRs)-2 and -4 mRNA expression, TNF-alpha expression and activity (20%) and increasing the expression of the cytokine IL-17 (40%) (P<0.05 vs hypoxia). Our findings also showed that BNP induced by ischemia was significantly and in a concentration-dependent manner reduced by irbesartan. The findings of our study demonstrated that the AT1 receptor antagonist irbesartan exerts a protective role in an in vitro hypoxic condition reducing oxidative stress and inflammation.

Key pointsThis analysis explored the association between complete remission of proteinuria and kidney function decline during sparsentan or irbesartan treatment. Patients achieving complete remission of proteinuria experienced better eGFR preservation and fewer kidney failure events. These data support Kidney Disease Improving Global Outcomes guideline recommendations to maintain proteinuria levels in IgA nephropathy ideally below 0.3 g/d.BackgroundIn the phase 3, randomized, double-blind PROTECT ( NCT03762850 ) trial, sparsentan, a single-molecule dual endothelin angiotensin receptor antagonist, reduced proteinuria and preserved kidney function compared with maximum labeled dose irbesartan in adults with IgA nephropathy. In this post hoc analysis of PROTECT, we assessed the association between complete remission of proteinuria (CR) and preservation of kidney function.MethodsThis analysis compared kidney function in patients who achieved CR (urine protein excretion ResultsOf 404 patients who were randomized and received study drug, 43 (11%) achieved CR36 and 85 (21%) achieved CR110. CR patients demonstrated greater and more rapid reductions in proteinuria compared with non-CR patients. CR110 patients had a smaller absolute change in eGFR versus non-CR patients (-4.0 versus -8.6 ml/min per 1.73 m 2 ) and a slower rate of eGFR decline (day 1-week 110; -0.7 versus -4.2 ml/min per 1.73 m 2 per year). Fewer CR110 patients (1%) reached the composite kidney end point versus non-CR patients (14%). CR110 patients were more likely to experience treatment-emergent adverse events associated with hypotension (hypotension, orthostatic hypotension, or BP systolic decreased) and less likely to experience treatment-emergent adverse events of hypertension than non-CR patients. More non-CR patients versus CR110 patients discontinued treatment due to AEs (11% versus 4%, respectively) or patient decision (8% versus 2%, respectively).ConclusionsParticipants in PROTECT who achieved CR36 or CR110 showed greater eGFR preservation, fewer kidney failure events, and similar safety profiles compared to non-CR participants. These data reinforce recommendations to maintain proteinuria levels ideally Clinical trial registry name and registration numberClinicalTrials.gov, NCT03762850 .