Aldosterone Synthase Inhibitors Research Articles

Safety and efficacy of once-daily dexfadrostat phosphate in patients with primary aldosteronism: a randomised, parallel group, multicentre, phase 2 trial

Primary aldosteronism (PA) is caused by autonomous aldosterone overproduction and characterised by uncontrolled hypertension. There are currently no treatments that targetaldosterone synthesis. We evaluated the safety and efficacy of a novel aldosterone synthase inhibitor, dexfadrostat phosphate, in patients with PA. This multi-centre, randomised, phase 2 trial was conducted between November 2019 and May 2022 (NCT04007406; EudraCT code 2019-000919-85). Adults with PA and an office systolic blood pressure of 145-190mmHg were included. After a 2-week single-blind placebo run-in period, participants were randomised 1:1:1 to receive oral dexfadrostat phosphate 4, 8, or 12mg once daily for an 8-week double-blind treatment period, followed by a 2-week single-blind placebo withdrawal period. Randomisation was conducted centrally and stratified by centre and sex. At the beginning and end of the treatment period, 24h ambulatory systolic blood pressure (aSBP) was recorded. Blood samples were taken every 2 weeks. Primary endpoints were the change in aldosterone-to-renin ratio (ARR) and mean 24h aSBP from baseline to the end of the treatment period in the combined dose group of all participants receiving any dose of dexfadrostat phosphate. Safety endpoints were the occurrence of treatment-emergent adverse events (TEAEs) and serious adverse events over the entire study in all randomised participants who received at least one dose of dexfadrostat phosphate. In total, 35 participants received dexfadrostat phosphate and all participants completed the study. Twenty-six participants (74.3%) were male, the mean age was 51.9 years (SD 8.7), and most were White (n=32, 91.4%). The median ARR and the mean 24h aSBP significantly decreased from the beginning to the end of the treatment period in the combined dose group (ARR: 15.3 vs 0.6, least-squares mean [LSM] change in log-normal values-2.5, p<0.0001; aSBP: 142.6 vs 131.9mmHg, LSM change-10.7mmHg, p<0.0001). There were no safety concerns; all TEAEs were mild or moderate and there were no serious TEAEs. Dexfadrostat phosphate corrected the ARR and aSBP and was well tolerated in patients with PA, demonstrating the benefit of pharmacologically targeting the source of hyperaldosteronism. DAMIAN Pharma AG.

Systematic Review Article: New Drug Strategies for Treating Resistant Hypertension-the Importance of a Mechanistic, Personalized Approach.

Resistant hypertension (RHT) is characterized by persistently high blood pressure (BP) levels above the widely recommended therapeutic targets of less than 140/90 mmHg office BP, despite life-style measures and optimal medical therapies, including at least three antihypertensive drug classes at maximum tolerated dose (one should be a diuretic). This condition is strongly related to hypertension-mediated organ damage and, mostly, high risk of hospitalization due to hypertension emergencies or acute cardiovascular events. Hypertension guidelines proposed a triple combination therapy based on renin angiotensin system blocking agent, a thiazide or thiazide-like diuretic, and a dihydropyridinic calcium-channel blocker, to almost all patients with RHT, who should also receive either a beta-blocker or a mineralocorticoid receptor antagonist, or both, depending on concomitant conditions and contraindications. Several other drugs may be attempted, when elevated BP levels persist in these RHT patients, although their added efficacy in lowering BP levels on top of optimal medical therapy is uncertain. Also, renal denervation has demonstrated to be a valid therapeutic alternative in RHT patients. More recently, novel drug classes and molecules have been tested in phase 2 randomised controlled clinical trials in patients with RHT on top of optimal medical therapy with at least 2-3 antihypertensive drugs. These novel drugs, which are orally administered and are able to antagonize different pathophysiological pathways, are represented by non-steroid mineralocorticorticoid receptor antagonists, selective aldosterone synthase inhibitors, and dual endothelin receptor antagonists, all of which have proven to reduce seated office and 24-h ambulatory systolic/diastolic BP levels. The main findings of randomizedclinicaltrialsperformed with these drugs as well as their potential indications for the clinical management of RHT patients are summarised in this systematic review article.

Molecular Targets of Novel Therapeutics for Diabetic Kidney Disease: A New Era of Nephroprotection.

Diabetic kidney disease (DKD) is a chronic microvascular complication in patients with diabetes mellitus (DM) and the leading cause of end-stage kidney disease (ESKD). Although glomerulosclerosis, tubular injury and interstitial fibrosis are typical damages of DKD, the interplay of different processes (metabolic factors, oxidative stress, inflammatory pathway, fibrotic signaling, and hemodynamic mechanisms) appears to drive the onset and progression of DKD. A growing understanding of the pathogenetic mechanisms, and the development of new therapeutics, is opening the way for a new era of nephroprotection based on precision-medicine approaches. This review summarizes the therapeutic options linked to specific molecular mechanisms of DKD, including renin-angiotensin-aldosterone system blockers, SGLT2 inhibitors, mineralocorticoid receptor antagonists, glucagon-like peptide-1 receptor agonists, endothelin receptor antagonists, and aldosterone synthase inhibitors. In a new era of nephroprotection, these drugs, as pillars of personalized medicine, can improve renal outcomes and enhance the quality of life for individuals with DKD.

Aldosterone synthase inhibitor (BI 690517) therapy for people with diabetes and albuminuric chronic kidney disease: A multicentre, randomized, double-blind, placebo-controlled, Phase I trial.

This Phase I study evaluated the safety and early efficacy of an aldosterone synthase inhibitor (BI 690517) in people with diabetes and albuminuric chronic kidney disease. Double-blind, placebo-controlled study (NCT03165240) at 40 sites across Europe. Eligible participants [estimated glomerular filtration rate ≥20 and <75 ml/min/1.73 m2 ; urine albumin/creatinine ratio (UACR) ≥200 and <3500 mg/g] were randomized 6:1 to receive once-daily oral BI 690517 3, 10 or 40 mg, or eplerenone 25-50 mg, or placebo, for 28 days. The primary endpoint was the proportion of participants with drug-related adverse events (AEs). Secondary endpoints included changes from baseline in the UACR. Fifty-eight participants were randomized and treated from 27 November 2017 to 16 April 2020 (BI 690517: 3 mg, n = 18; 10 mg, n = 13; 40 mg, n = 14; eplerenone, n = 4; placebo, n = 9) for 28 days. Eight (13.8%) participants experienced drug-related AEs [BI 690517: 3 mg (two of 18); 10 mg (four of 13); 40 mg (two of 14)], most frequently constipation [10 mg (one of 13); 40 mg (one of 14)] and hyperkalaemia [3 mg (one of 18); 10 mg (one of 13)]. Most AEs were mild to moderate; one participant experienced severe hyperkalaemia (serum potassium 6.9 mmol/L; BI 690517 10 mg). UACR responses [≥20% decrease from baseline (first morning void urine) after 28 days] were observed for 80.0% receiving BI 690517 40 mg (eight of 10) versus 37.5% receiving placebo (three of eight). Aldosterone levels were suppressed by BI 690517, but not eplerenone or placebo. BI 690517 was generally well tolerated, reduced plasma aldosterone and may decrease albuminuria in participants with diabetes and albuminuric chronic kidney disease.

Use of Genomics to Develop Novel Therapeutics and Personalize Hypertension Therapy.

Hypertension is a prevalent public health problem, contributing to >10 million deaths annually. Though multiple therapeutics exist, many patients suffer from treatment-resistant hypertension or try several medications before achieving blood pressure control. Genomic advances offer mechanistic understanding of blood pressure variability, therapeutic targets, therapeutic response, and promise a stratified approach to treatment of primary hypertension. Cyclic guanosine monophosphate augmentation, aldosterone synthase inhibitors, and angiotensinogen blockade with silencing RNA and antisense therapies are among the promising novel approaches. Pharmacogenomic studies have also been done to explore the genetic bases underpinning interindividual variability in response to existing therapeutics. A polygenic approach using risk scores is likely to be the next frontier in stratifying responses to existing therapeutics.

Emerging Therapies for Treatment-Resistant Hypertension: A Review of Lorundrostat and Related Selective Aldosterone Synthase Inhibitors.

The target-hypertension (Target-HTN) trial investigated the efficacy and safety of lorundrostat, an aldosterone synthase inhibitor, as an antihypertensive. Cohort 1 of the trial includes patients with suppressed plasma renin activity and elevated aldosterone levels. Lorundrostat doses of 100 mg and 50 mg daily significantly decreased systolic blood pressure compared to the placebo group. Cohort 2 also demonstrated a reduction in systolic blood pressure with the 100 mg daily dose of lorundrostat. Lorundrostat is more selective for the inhibition of CYP11B2 versus CYP11B1, which makes it preferable to other aldosterone synthase inhibitors that inhibit cortisol synthesis, such as osilodrostat. Phase 3 trials are needed to validate the safety and efficacy of lorundrostat, and further research should be performed on other selective aldosterone synthase inhibitors such as baxdrostat, dexfadrostat, and BI 690517.

Investigating Baxdrostat and Its Derivatives as Aldosterone Synthase Inhibitors for Resistant Hypertension: An In Silico Approach

AbstractResistant hypertension, a severe condition affecting about 10 % of people with high blood pressure, significantly increases the risk of heart, brain, and kidney issues. This study investigates the potential of baxdrostat and its derivatives (1–22) as aldosterone synthase inhibitors for resistant hypertension using in silico methods. The study employed various computational methods, including molecular dynamics simulation (MD), molecular docking, frontier molecular orbital (FMO) analysis, and global chemical descriptors, to evaluate the interactions between the compounds and the target proteins. The docking results showed that compounds 2, 5, 7, and baxdrostat had binding affinities of −7.8 kcal/mol, −10.9 kcal/mol, −10.6 kcal/mol, and −9.3 kcal/mol, respectively. Additionally, molecular dynamics simulations revealed that ligands 2, 5, and baxdrostat formed the most stable protein‐ligand complexes with aldosterone synthase. The complex of the 4FDH‐baxdrostat remained highly stable across all tested temperatures (300 K, 305 K, 310 K, and 320 K), consistently displaying low RMSD values, with the minimum observed at 305 K. Baxdrostat emerges as the most promising candidate among the compounds examined, showcasing notable potential when considering a combination of in vitro, in vivo, and now in silico data. While baxdrostat remains the primary candidate based on comprehensive in vitro, in vivo, and in silico studies, further analysis using FMO theory suggests that ligands 2 and 5 have promising potential due to their smaller Egap. To validate these findings, further clinical investigations are warranted.

Aldosterone Synthase Inhibitors and Mineralocorticoid Receptor Antagonists: Competitors or Collaborators?

Aldosterone Synthase Inhibitors and Mineralocorticoid Receptor Antagonists: Competitors or Collaborators?

Aldosterone Synthase Inhibitors for Treatment of Hypertension and Chronic Kidney Disease

Aldosterone excess is known to worsen hypertension and kidney function. Three selective aldosterone synthase inhibitors (ASIs) were evaluated in 3 phase 2 trials. In the first study, the ASI baxdrostat 2 mg orally once daily decreased systolic blood pressure (SBP) by 11.0 mmHg compared with placebo after 12 weeks in patients with treatment-resistant hypertension. In the second study including patients with uncontrolled hypertension, placebo-corrected reduction in SBP with lorundrostat 50 mg once daily was 9.6 mmHg after 8 weeks. Patients receiving thiazides and those with body mass index (BMI) &gt; 30 kg/m2 had the optimum blood pressure (BP) response to lorundrostat, whereas plasma renin activity (PRA) did not affect its antihypertensive potency. In the third trial including patients with chronic kidney disease (CKD), the ASI BI 690517 (10 mg once daily) decreased urinary albumin creatinine ratio (UACR) by 39% after 14 weeks compared with 3% reduction with placebo. Reduction in UACR was generally similar in presence or absence of concomitant treatment with empagliflozin. The 3 ASIs mildly decreased (by &lt;15%) estimated glomerular filtration rate (eGFR) compared with placebo. The most common adverse effects of ASIs were hyperkalemia occurring in 2.9% and 7.9% among patients randomized to baxdrostat and lorundrostat, respectively versus none in the placebo groups. In patients with CKD, frequency of hyperkalemia was higher: 14.2% and 6.0% with BI 690517 and placebo, respectively. Adrenal insufficiency was reported in 1.3% of patients randomized to BI 690517 versus 1.0% with placebo. Preliminary data suggest that selective ASIs are effective in lowering BP in patients with resistant and uncontrolled hypertension and decreasing albuminuria in CKD. Phase 3 clinical trials should be conducted to assess long-term efficacy and safety of ASIs in a wide spectrum of patients with uncontrolled BP and CKD.

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&lt;0.01, 90% CI: -25.5 to -7.9 mmHg) and -12.3 mmHg (N=12, p&lt;0.03, 90% CI: -21.6 to -3.1 mmHg) in subjects with body mass index (BMI) &gt; 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&lt;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.