Aldosterone Synthase Inhibitors Research Articles

Aldosterone and aldosterone synthase inhibitors in cardiorenal disease.

Modulation of the renin-angiotensin-aldosterone system is a foundation of therapy for cardiovascular and kidney diseases. Excess aldosterone plays an important role in cardiovascular disease, contributing to inflammation, fibrosis, and dysfunction in the heart, kidneys, and vasculature through both genomic and mineralocorticoid receptor (MR)-mediated as well as nongenomic mechanisms. MR antagonists have been a key therapy for attenuating the pathologic effects of aldosterone but are associated with some side effects and may not always adequately attenuate the nongenomic effects of aldosterone. Aldosterone is primarily synthesized by the CYP11B2 aldosterone synthase enzyme, which is very similar in structure to other enzymes involved in steroid biosynthesis including CYP11B1, a key enzyme involved in glucocorticoid production. Lack of specificity for CYP11B2, off-target effects on the hypothalamic-pituitary-adrenal axis, and counterproductive increased levels of bioactive steroid intermediates such as 11-deoxycorticosterone have posed challenges in the development of early aldosterone synthase inhibitors such as osilodrostat. In early-phase clinical trials, newer aldosterone synthase inhibitors demonstrated promise in lowering blood pressure in patients with treatment-resistant and uncontrolled hypertension. It is therefore plausible that these agents offer protection in other disease states including heart failure or chronic kidney disease. Further clinical evaluation will be needed to clarify the role of aldosterone synthase inhibitors, a promising class of agents that represent a potentially major therapeutic advance.

Efficacy and safety of aldosterone synthase inhibition with and without empagliflozin for chronic kidney disease: a randomised, controlled, phase 2 trial

Excess aldosterone accelerates chronic kidney disease progression. This phase 2 clinical trial assessed BI 690517, an aldosterone synthase inhibitor, for efficacy, safety, and dose selection. This was a multinational, randomised, controlled, phase 2 trial. People aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 30 to less than 90 mL/min/1·73 m2, a urine albumin to creatinine ratio (UACR) of 200 to less than 5000 mg/g, and serum potassium of 4·8 mmol/L or less, taking an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker, were enrolled. Participants were randomly assigned (1:1) to 8 weeks of empagliflozin or placebo run-in, followed by a second randomisation (1:1:1:1) to 14 weeks of treatment with once per day BI 690517 at doses of 3 mg, 10 mg, or 20 mg, or placebo. Study participants, research coordinators, investigators, and the data coordinating centre were masked to treatment assignment. The primary endpoint was the change in UACR measured in first morning void urine from baseline (second randomisation) to the end of treatment. This study is registered with ClinicalTrials.gov (NCT05182840) and is completed. Between Feb 18 and Dec 30, 2022, of the 714 run-in participants, 586 were randomly assigned to receive BI 690517 or placebo. At baseline, 33% (n=196) were women, 67% (n=390) were men, 42% (n=244) had a racial identity other than White, and mean participant age was 63·8 years (SD 11·3). Mean baseline eGFR was 51·9 mL/min/1·73 m2 (17·7) and median UACR was 426 mg/g (IQR 205 to 889). Percentage change in first morning void UACR from baseline to the end of treatment at week 14 was -3% (95% CI -19 to 17) with placebo, -22% (-36 to -7) with BI 690517 3 mg, -39% (-50 to -26) with BI 690517 10 mg, and -37% (-49 to -22) with BI 690517 20 mg monotherapy. BI 690517 produced similar UACR reductions when added to empagliflozin. Investigator-reported hyperkalaemia occurred in 10% (14/146) of those in the BI 690517 3 mg group, 15% (22/144) in the BI 690517 10 mg group, and 18% (26/146) in the BI 690517 20 mg group, and in 6% (nine of 147) of those receiving placebo, with or without empagliflozin. Most participants with hyperkalaemia did not require intervention (86% [72/84]). Adrenal insufficiency was an adverse event of special interest reported in seven of 436 study participants (2%) receiving BI 690517 and one of 147 participants (1%) receiving matched placebo. No treatment-related deaths occurred during the study. BI 690517 dose-dependently reduced albuminuria with concurrent renin-angiotensin system inhibition and empagliflozin, suggesting an additive efficacy for chronic kidney disease treatment without unexpected safety signals. Boehringer Ingelheim.

Discovery of a Potent Dual Inhibitor of Aromatase and Aldosterone Synthase

Discovery of a Potent Dual Inhibitor of Aromatase and Aldosterone Synthase

Abstract 17143: Lorundrostat for Treatment of Obesity-Related, Aldosterone-Dependent Hypertension - An Endotype-Specific, Targeted Approach to the Treatment of Uncontrolled Hypertension

Hyperaldosteronism manifests as low renin hypertension (HTN) with endothelial dysfunction and vascular fibrosis. In the aging vasculature, these pathological changes may be exacerbated by non-genomic aldosterone signaling via GPER (GPR30), which is not inhibited by mineralocorticoid receptor antagonists (MRA). In trials with healthy subjects and patients with uncontrolled HTN, the novel, highly selective aldosterone synthase inhibitor, lorundrostat, reduced median morning plasma aldosterone concentration (PAC) by approximately 70%. PAC reduction was dose-dependent and associated with a mean placebo-adjusted reduction in systolic blood pressure (BP) of -16.7 mmHg (N=15, p<0.01, 90% CI: -25.5 to -7.9 mmHg) and -12.3 mmHg (N=12, p<0.03, 90% CI: -21.6 to -3.1 mmHg) in subjects with body mass index (BMI) > 30 kg/m 2 receiving 50mg or 100mg QD of lorundrostat, respectively. In contrast, in non-obese individuals, BP reductions were modest and not statistically significant. Salutary BP effects of 100mg QD lorundrostat at week 8 were observed in individuals with normal to high renin (N=30, -11.4 ± 2.5 mmHg) and low renin (N=25, -11.9 ± 2.8 mmHg). Linkage between obesity, HTN and increased aldosterone has been suggested by studies in a mouse model of obesity, hyperleptinemia and HTN. In this model, both leptin receptor blockade and lorundrostat restored normal BP. As anticipated, in the Phase 2 trial, mean serum leptin was elevated at baseline in obese (N=103, 37.8 ± 2.4 ng/mL) v. non-obese (N=88, 21.6 ± 1.9 ng/mL, p<0.001) individuals with uncontrolled HTN and could be a useful biomarker to identify lorundrostat-responsive HTN. MRAs are recommended as fourth-line therapy for resistant HTN. However, MRAs can be associated with hormonal side-effects and stimulate excess aldosterone production that may increase non-genomic signaling, endothelial dysfunction and vessel wall remodeling. Lorundrostat has neither of these liabilities and may be an important new antihypertensive. Renin-independent, leptin- and aldosterone-dependent HTN defines a unique endotype in obese hypertensive individuals. Endotype-targeted therapy may allow early identification, intervention and improved BP control in obese individuals.

Aldosterone synthase inhibitor "Baxdrostat" for resistant hypertension: A clinical approach or futuristic idea?

Aldosterone synthase inhibitor "Baxdrostat" for resistant hypertension: A clinical approach or futuristic idea?

Redefining primary hyperaldosteronism as "The Syndrome of Inappropriate Aldosterone Secretion (SIALDS)": A common but unrecognized cause of hypertension.

The current screening and diagnostic recommendations for detecting Primary Hyperaldosteronism (PHA) focus on diagnosing the more severe and overt instances of renin-independent aldosterone production. However, milder forms of autonomous aldosterone secretion have been demonstrated to exist below the diagnostic thresholds of current PHA guidelines, and associate with clinically relevant cardiovascular risk. PHAencompasses a spectrum of renin independent aldosterone production, progressing from a subclinical state in normotensives to a full-blown clinical syndrome representing the resistant hypertension population. The authors propose the Syndrome of Inappropriately Elevated Aldosterone Secretion (SIALDS) concept as a potential new paradigm for understanding and diagnosing PHA and expanded diagnostic approach to improve early detection even in well-controlled hypertension. The authors also delve into the impact of treatments, including mineralocorticoid receptor antagonists and emerging aldosterone synthase inhibitors. Furthermore, The authors outline future research directions, proposing clinical trials to investigate the long-term identification and treatment outcomes of SIALDS.

Taming resistant hypertension: The promise of novel pharmacologic approaches and renal denervation.

Resistant hypertension is associated with an exceedingly high cardiovascular risk and there remains an unmet therapeutic need driven by pathophysiologic pathways unaddressed by guideline-recommended therapy. While spironolactone is widely considered as the preferable fourth-line drug, its broad application is limited by its side effect profile, especially off-target steroid receptor-mediated effects and hyperkalaemia in at-risk subpopulations. Recent landmark trials have reported promising safety and efficacy results for a number of novel compounds targeting relevant pathophysiologic pathways that remain unopposed by contemporary drugs. These include the dual endothelin receptor antagonist, aprocitentan, the aldosterone synthase inhibitor, baxdrostat and the nonsteroidal mineralocorticoid receptor antagonist finerenone. Furthermore, the evidence base for consideration of catheter-based renal denervation as a safe and effective adjunct therapeutic approach across the clinical spectrum of hypertension has been further substantiated. This review will summarise the recently published evidence on novel antihypertensive drugs and renal denervation in the context of resistant hypertension.

Extra-adrenal aldosterone: a mini review focusing on the physiology and pathophysiology of intrarenal aldosterone.

Accumulating evidence has demonstrated the existence of extra-adrenal aldosterone in various tissues, including the brain, heart, vascular, adipocyte, and kidney, mainly based on the detection of the CYP11B2 (aldosterone synthase, cytochrome P450, family 11, subfamily B, polypeptide 2) expression using semi-quantitative methods including reverse transcription-polymerase chain reaction and antibody-based western blotting, as well as local tissue aldosterone levels by antibody-based immunosorbent assays. This mini-review highlights the current evidence and challenges in extra-adrenal aldosterone, focusing on intrarenal aldosterone. A narrative review. Locally synthesized aldosterone may play a vital role in various physio-pathological processes, especially cardiovascular events. The site of local aldosterone synthesis in the kidney may include the mesangial cells, podocytes, proximal tubules, and collecting ducts. The synthesis of renal aldosterone may be regulated by (pro)renin receptor/(pro)renin, angiotensin II/Angiotensin II type 1 receptor, wnt/β-catenin, cyclooxygenase-2/prostaglandin E2, and klotho. Enhanced renal aldosterone release promotes Na+ reabsorption and K+ excretion in the distal nephron and may contribute to the progress of diabetic nephropathy and salt-related hypertension. Inhibition of intrarenal aldosterone signaling by aldosterone synthase inhibitors or mineralocorticoid receptor antagonists may be a hopeful pharmacological technique for the therapy of diabetic nephropathy and saltrelated hypertension. Yet, current reports are often conflicting or ambiguous, leading many to question whether extra-adrenal aldosterone exists, or whether it is of any physiological and pathophysiological significance.

New Potential Treatments for Resistant Hypertension.

To provide an update and review approaches to the treatment of resistant hypertension (RH) with a focus on emerging potential therapies. Resistant hypertension is defined as a blood pressure that remains elevated above a patient's individualized target despite the concurrent use of 3 antihypertensive agents of different classes including a diuretic or use of 4 or more antihypertensive agents. Patients with RH have an increased risk of adverse cardiovascular and renal outcomes. Most RH is attributed to apparent RH and is not true RH. True RH is a diagnosis of exclusion after apparent RH has been excluded. Treatment of RH is challenging, and blood pressure goal is often difficult to achieve. Currently several new therapies have emerged with forthcoming data that provide promise for improved blood pressure control in those with resistant hypertension. Once RH has been diagnosed, patients should be on standardized therapy that includes agents from three different classes including a diuretic with addition in most cases of a mineralocorticoid as a fourth line agent. There are newer agents in development currently being studied in clinical trials including dual endothelin receptor antagonists and aldosterone synthase inhibitors that appear to be efficacious. Other approved medications including SGLT2 inhibitors and non-steroidal mineralocorticoids such as finerenone also need to be incorporated into treatment paradigms. Renal denervation with catheter based devices is another potential promising treatment option in this population.

New trials in resistant hypertension: mixed blessing stories.

Resistant hypertension (RH) is linked to an increased risk of cardiovascular and renal complications. Treatment options include non-pharmacological interventions, such as lifestyle modifications, and the use of specific antihypertensive drug combinations, including diuretics. Renal denervation is another option for treatment-resistant hypertension. New compounds targeting different pathways involved in RH-including inhibitors of aminopeptidase A, endothelin antagonists and selective aldosterone synthase inhibitors-have been tested in clinical trials in this condition. The centrally acting drug firibastat, targeting the brain renin-angiotensin system, failed to demonstrate significant effectiveness in reducing blood pressure (BP) in patients with difficult-to-treat and RH in the Firibistat in Resistant Hypertension (FRESH) trial. Aprocitentan, a dual endothelin A and B receptor antagonist, showed a moderate but statistically significant decrease in BP in patients with RH in the Parallel-Group, Phase 3 Study with Aprocitentan in Subjects with Resistant Hypertension (PRECISION) trial. However, concerns remain about potential adverse events, such as fluid retention. The use of baxdrostat, a selective aldosterone synthase inhibitor, showed promising results in reducing BP in patients with treatment-resistant hypertension in the Baxdrostat in Resistant Hypertension (BrigHTN) trial. However, a subsequent trial, HALO, failed to meet its primary endpoint. The unexpected results may be influenced by factors such as patient adherence and white-coat hypertension. Despite the disappointing results from HALO, the potential benefits of inhibiting aldosterone synthesis remain to be fully understood. In conclusion, managing RH remains challenging, and new compounds like firibastat, aprocitentan and baxdrostat have shown varied effectiveness. Further research is needed to improve our understanding and treatment of this condition.

Aldosterone Synthase Inhibition With Lorundrostat for Uncontrolled Hypertension

Excess aldosterone production contributes to hypertension in both classical hyperaldosteronism and obesity-associated hypertension. Therapies that reduce aldosterone synthesis may lower blood pressure. To compare the safety and efficacy of lorundrostat, an aldosterone synthase inhibitor, with placebo, and characterize dose-dependent safety and efficacy to inform dose selection in future trials. Randomized, placebo-controlled, dose-ranging trial among adults with uncontrolled hypertension taking 2 or more antihypertensive medications. An initial cohort of 163 participants with suppressed plasma renin (plasma renin activity [PRA] ≤1.0 ng/mL/h) and elevated plasma aldosterone (≥1.0 ng/dL) were enrolled, with subsequent enrollment of 37 participants with PRA greater than 1.0 ng/mL/h. Participants were randomized to placebo or 1 of 5 dosages of lorundrostat in the initial cohort (12.5 mg, 50 mg, or 100 mg once daily or 12.5 mg or 25 mg twice daily). In the second cohort, participants were randomized in a 1:6 ratio to placebo or lorundrostat, 100 mg once daily. The primary end point was change in automated office systolic blood pressure from baseline to study week 8. Between July 2021 and June 2022, 200 participants were randomized, with final follow-up in September 2022. Following 8 weeks of treatment in participants with suppressed PRA, changes in office systolic blood pressure of -14.1, -13.2, -6.9, and -4.1 mm Hg were observed with 100 mg, 50 mg, and 12.5 mg once daily of lorundrostat and placebo, respectively. Observed reductions in systolic blood pressure in individuals receiving twice-daily doses of 25 mg and 12.5 mg of lorundrostat were -10.1 and -13.8 mm Hg, respectively. The least-squares mean difference between placebo and treatment in systolic blood pressure was -9.6 mm Hg (90% CI, -15.8 to -3.4 mm Hg; P = .01) for the 50-mg once-daily dose and -7.8 mm Hg (90% CI, -14.1 to -1.5 mm Hg; P = .04) for 100 mg daily. Among participants without suppressed PRA, 100 mg once daily of lorundrostat decreased systolic blood pressure by 11.4 mm Hg (SD, 2.5 mm Hg), which was similar to blood pressure reduction among participants with suppressed PRA receiving the same dose. Six participants had increases in serum potassium above 6.0 mmol/L that corrected with dose reduction or drug discontinuation. No instances of cortisol insufficiency occurred. Among individuals with uncontrolled hypertension, use of lorundrostat was effective at lowering blood pressure compared with placebo, which will require further confirmatory studies. ClinicalTrials.gov Identifier: NCT05001945.

Abstract 113: Aldosterone Synthase Inhibition With Lorundrostat For The Treatment Of Uncontrolled Hypertension: The Target-HTN Randomized Clinical Trial

Importance: Excess aldosterone production contributes to hypertension in both classical hyperaldosteronism and obesity-associated hypertension. Objective: To compare the safety and efficacy of lorundrostat, an aldosterone synthase inhibitor, with placebo, and characterize dose-dependent safety and efficacy. Design, Setting, and Participants: Randomized, placebo-controlled, dose-ranging, double-blind clinical trial among adults with uncontrolled hypertension taking 2 or more antihypertensive medications. A first cohort of participants with suppressed plasma renin (plasma renin activity (PRA) of less than 1.0 ng/mL/h) and elevated plasma aldosterone (greater than 1.0 ng/dL) were enrolled (n=163), with subsequent enrollment of participants with PRA greater than 1.0 ng/mL/h (n=37). Interventions: Participants were randomized to placebo or one of five doses of lorundrostat (12.5, 50, or 100 mg once daily, or 12.5 or 25 mg twice daily.) Results: Following 8 weeks of treatment in participants with suppressed PRA, dose-dependent changes in office systolic BP were observed (figure). The primary endpoint, placebo-subtracted change in modeled systolic BP was -9.6 mmHg (90% confidence interval [CI], -15.8 to -3.4, p=0.01) for the 50 mg once daily dose and -7.8 mmHg (90% CI, -14.1 to -1.5, p=0.04) for 100 mg daily. Six participants had increases in serum potassium above 6.0 mmol/L that were reversed with dose reduction or drug discontinuation. Conclusions and Relevance: Among individuals with uncontrolled hypertension, use of lorundrostat was effective at lowering blood pressure compared with placebo.

Baxdrostat: An Aldosterone Synthase Inhibitor for the Treatment of Systemic Hypertension.

Systemic hypertension remains one of the leading cause of morbidity and mortality in the United States and throughout the world. Baxdrostat (CIN-107), a new drug developed by Roche is a selective aldosterone synthase inhibitor that is being evaluated as one of the potential treatments for hypertension, especially in patients with drug treatment-resistant hypertension. An increased level of aldosterone is associated with inflammation, systemic hypertension, and organ fibrosis, contributing to adverse cardiovascular events. A phase 2 trial, BrigHTN, showed promising results in demonstrating the efficacy of baxdrostat, where The HALO (efficacy and safety of baxdrostat in patients with uncontrolled hypertension) trial did not demonstrate any blood pressure-lowering benefit of baxdrostat when compared with the placebo. Several additional studies are now underway to evaluate the effectiveness of baxdrostat as an anti-hypertensive agent.

Adverse effects of an aldosterone synthase (CYP11B2) inhibitor, fadrozole (FAD286), on inflamed rat colon.

Recently, we described local aldosterone production in the murine large intestine. Upregulated local aldosterone synthesis in different tissues has been linked with inflammatory conditions, which have been attenuated by the aldosterone synthase (CYP11B2) inhibitor, fadrozole (FAD286). Therefore, we investigated the effect of inhibition of intestinal aldosterone synthesis on the development of intestinal inflammation. Sprague-Dawley rats were administered 5% (v/w) dextran sodium sulphate (DSS) for 7days with or without daily FAD286 (30 mg/kg/d) subcutaneous injections on 3days before, during and one day after DSS. Tissue aldosterone concentrations were evaluated by ELISA, CYP11B2 by Western blot and RT-qPCR. FAD286 halved adrenal aldosterone production but, intriguingly, increased the colonic aldosterone concentration. The lack of inhibitory effect of FAD286 in the colon might have been affected by the smaller size of colonic vs. adrenal CYP11B2, as seen in Western blot. When combined with DSS, FAD286 aggravated the macroscopic and histological signs of intestinal inflammation, lowered the animals' body weight gain and increased the incidence of gastrointestinal bleeding and the permeability to iohexol in comparison to DSS-animals. To conclude, FAD286 exerted harmful effects during intestinal inflammation. Local intestinal aldosterone did not seem to play any role in the inflammatory pathogenesis occurring in the intestine.

Novel mechanisms of salt-sensitive hypertension

A high dietary sodium-consumption level is considered the most important lifestyle factor that can be modified to help prevent an increase in blood pressure and the development of hypertension. Despite numerous studies over the past decades, the pathophysiology explaining why some people show a salt-sensitive blood pressure response and others do not is incompletely understood. Here, a brief overview of the latest mechanistic insights is provided, focusing on the mononuclear phagocytic system and inflammation, the gut-kidney axis, and epigenetics. The article also discusses the effects of 3 types of novel drugs on salt-sensitive hypertension-sodium-glucose cotransporter 2 inhibitors, nonsteroidal mineralocorticoid receptor antagonists, and aldosterone synthase inhibitors. The conclusion is that besides kidney-centered mechanisms, vasoconstrictor mechanisms are also relevant for both the understanding and treatment of this blood pressure phenotype.

#3318 PHASE II DOSE-SELECTION, RANDOMISED DOUBLE-BLIND TRIAL OF THE ASI, BI 690517, ALONE AND IN COMBINATION WITH EMPA IN PEOPLE WITH CKD

Abstract Background and Aims Elevated aldosterone levels are associated with chronic kidney disease (CKD) progression and adverse kidney and cardiovascular disease outcomes. Therapy with an angiotensin-converting enzyme inhibitor (ACEi) or angiotensin receptor blocker (ARB) improves clinical outcomes, yet elevated aldosterone levels often persist. BI 690517 is a first-in-class, selective aldosterone synthase inhibitor (ASi) that may reduce deleterious mineralocorticoid receptor-dependent and -independent actions of aldosterone. Coadministration of BI 690517 with a sodium–glucose cotransporter-2 inhibitor could mitigate the risk of hyperkalaemia. This study is investigating the efficacy and safety of three doses of BI 690517, alone and in combination with empagliflozin (EMPA), on top of an ACEi or ARB, for treatment of CKD with or without type 2 diabetes. Method A randomised, double-blind, placebo-controlled, parallel-dose Phase II trial (NCT05182840) in adults with or without type 2 diabetes who had an estimated glomerular filtration rate (eGFR) ≥30 and <90 mL/min/1.73 m2, urine albumin:creatinine ratio (UACR) ≥200 and <5000 mg/g, and serum potassium ≤4.8 mmol/L on stable background therapy with an ACEi or ARB. After an 8-week run-in period to assigned background therapy (EMPA 10 mg or matched placebo randomised 1:1), participants were randomised 1:1:1:1 to BI 690517 (low, medium or high dose) or matched placebo for 14 weeks. Primary outcome was the change in UACR measured in a first morning void (UACRFMV) from baseline to Week 14. Secondary outcomes were the proportion of participants with ≥15 and 30% decreases in UACRFMV. Safety outcomes and changes in eGFR and serum potassium were also evaluated. Results Recruitment is complete, with 1719 participants from 168 sites in 29 countries screened. In total, 714 were randomised and entered the run-in period (last randomisation on 30 December 2022). The trial is currently ongoing; data on baseline characteristics will become available and shared. Conclusion This study will provide key data on the potential synergistic kidney-protective effects and safety of combination therapy with BI 690517 plus EMPA, as well as data on monotherapy, for CKD with or without type 2 diabetes. Findings will inform BI 690517 dose selection for further clinical trial development.

Effects of 20-hydroxyecdysone on UVB-induced photoaging in hairless mice

We recently reported that exposure of skin to ultraviolet B (UVB) irradiation for 2 weeks induces stress and accelerates skin aging. Interestingly, aldosterone synthase is known to be crucial in generating UVB-induced stress-related responses, suggesting that drugs that regulate its activity can be used as skin antiaging agents. Through extensive drug screening, we have identified 20-hydroxyecdysone (20E), a steroidal prohormone secreted by the prothoracic glands of insects, as a potent inhibitor of UVB-induced aging. Although 20E has been shown to exert antistress and anti-collagenase effects in vitro, its effects in vivo remain unexplored. Furthermore, the pharmacological and physiological effects of 20E on UVB-mediated photoaging are poorly understood. Therefore, in this study, we investigated the effects of 20E on aldosterone synthase and UVB-induced photoaging and skin lesions in hairless mice, focusing on the stress-related hypothalamic–pituitary–adrenal axis. We confirmed that 20E inhibited aldosterone synthase and reduced corticosterone levels. When applied to a UV-induced skin aging animal model, it ameliorated UV-induced stress and protected against the decrease in collagen levels. Importantly, when the aldosterone synthase inhibitor osilodrostat, an FDA-approved drug, was applied to the UV-induced skin aging model, the stress-reducing and antiaging effects of 20E were not observed. Thus, we conclude that 20E inhibits UVB-induced skin aging by blocking aldosterone synthase and is a potential candidate to prevent skin aging.

CYP11B2 inhibitor dexfadrostat phosphate suppresses the aldosterone-to-renin ratio, an indicator of sodium retention, in healthy volunteers.

High aldosterone is a key driver of hypertension and long-term negative sequelae. We evaluated the safety and efficacy of dexfadrostat phosphate (DP13), a novel aldosterone synthase (CYP11B2) inhibitor, in healthy participants. This randomized, double-blind, placebo-controlled study was conducted in two parts. In part A, a single-ascending dose escalation, 16 participants received oral DP13 1-16 mg. Part B was a multiple-ascending dose, sequential group study in which 32 participants received oral DP13 4, 8 or 16 mg once daily for 8 days. Safety and tolerability were monitored throughout. An adrenocorticotropic hormone (ACTH) stimulation test at maximal blood drug concentrations defined the dose range for multiple dosing. DP13 was well tolerated at all doses, with no serious adverse events. In part B, all DP13 doses (4, 8 and 16 mg) over 8 days effectively suppressed aldosterone production, increased the urinary sodium/potassium ratio, decreased plasma sodium and increased plasma potassium and renin levels compared with placebo, resulting in potent suppression of the aldosterone-to-renin ratio (ARR). Endocrine counter-regulation resulted in the 4 mg dose no longer sustaining 24-h aldosterone suppression after 8 days of treatment, unlike the 8- and 16 mg doses. There was no evidence of drug-induced adrenal insufficiency (ACTH stress challenge). In patients with excess aldosterone and ensuing sodium retention driving hypertension, managing sodium balance is critical. A CYP11B2 inhibitor like DP13, whose effectiveness can be monitored by a reduction in ARR, may prove valuable in managing aldosterone-dependent hypertension and primary aldosteronism.

Aldosterone Synthase Inhibitors and Dietary Interventions: A Combined Novel Approach for Prevention and Treatment of Cardiovascular Disease.

Systemic hypertension (HTN) is the hallmark of cardiovascular disease and the forerunner of heart failure. These associations have been established over decades of research on essential HTN. Advancements in the treatment of patients diagnosed with HTN, consisting of alpha- or beta-adrenergic receptor blockers, calcium channel blockers, angiotensin-converting enzyme inhibitors, thiazide, or aldosterone receptor blockers known as anti-mineralocorticoids, in the presence or absence of low sodium salt diets, often fail to control blood pressure adequately to prevent morbidity and mortality. Low sodium diets have had limited success in controlling HTN because low sodium intake is associated with renin-angiotensin-aldosterone system upregulation. Therefore, upregulating aldosterone secretion, sodium, and water retention which, in turn, moves the blood pressure back toward the range of HTN dictated by the baroreceptor reset value, as a compensatory mechanism, especially in resistant HTN. These impediments to blood pressure control in HTN may have been effectively circumvented by the advent of a new class of drugs known as aldosterone synthase inhibitors, represented by baxdrostat.The mechanism of action of baxdrostat as an aldosterone synthase inhibitor demonstrates the inextricable linkage between sodium and blood pressure regulation. Theoretically, combining a low sodium diet with the activity of this aldosterone synthesis inhibitor should alleviate the adverse effect of renin-angiotensin-aldosterone system upregulation. Aldosterone synthesis inhibition should also decrease the oxidative stress and endothelial dysfunction associated with HTN, causing more endothelial nitric oxide synthesis, release, and vasorelaxation. To the best of our knowledge, this is the first systematic review to summarize evidence-based articles relevant to the use of a novel drug (aldosterone synthase inhibitor) in the treatment of HTN and cardiovascular disease. Making the current database of relevant information on baxdrostat and other aldosterone synthase inhibitors readily available will, no doubt, aid physicians and other medical practitioners in their decision-making about employing aldosterone synthase inhibitors in the treatment of patients.

Aldosterone Synthase Inhibitors and the Treatment of Essential Hypertension.

Approximately 10% of hypertensive patients have treatment-resistant hypertension defined as uncontrolled hypertension despite taking effective doses of 3 classes of antihypertensive drugs including a calcium channel blocker, thiazide diuretic, and an angiotensin-converting enzyme inhibitor or angiotensin-2 receptor blocker. The Pathway-2 study of treatment-resistant hypertensives randomized to receive an additional low dose of spironolactone demonstrated that addition of the mineralocorticoid receptor (MR) antagonist lowered the blood pressure (BP) more effectively than placebo, bisoprolol, or doxazosin. The extent of BP lowering by spironolactone was predicted by the baseline aldosterone–renin ratio (1). Aldosterone excess is common in patients with treatment-resistant hypertension and about 20% of these patients meet current criteria for primary aldosteronism (PA) (2). The importance of aldosterone synthesis in primary hypertension was demonstrated several decades ago by lowering the BP of patients with low renin hypertension with aminoglutethimide, an inhibitor of the mitochondrial side chain cleavage enzyme (CYP11A1) (3). Only aldosterone levels significantly decreased; those of deoxycorticosterone, cortisol, and other steroids were unchanged or increased (3). Spironolactone, the most used MR antagonist, has significant adverse effects including hyperkalemia and off-target effects through the androgen and progesterone receptors. Newer more selective MR antagonists including eplerenone and finerenone are less effective antihypertensives. An alternative approach to treat hypertension due to inappropriate aldosterone levels is to target its synthesis.