Pharmacokinetics, distribution, and disposition of esaxerenone, a novel, highly potent and selective non-steroidal mineralocorticoid receptor antagonist, in rats and monkeys

Non-steroidal mineralocorticoid receptor antagonists in patients with chronic kidney disease and type 2 diabetes

Chronic kidney disease (CKD) in patients with type 2 diabetes (T2D) is a major health challenge associated with a disproportionately high burden of end-stage renal disease, cardiovascular disease and death. This review summarizes the rationale, clinical evidence and practical implementation for non-steroidal mineralocorticoid receptor antagonists (nsMRAs), a drug class now approved and recommended for patients with T2D and CKD at risk of cardiorenal disease progression. Three nsMRAs (finerenone, esaxerenone and apararenone) have been evaluated but finerenone is currently the only approved nsMRA for this indication. Two large-scale, placebo-controlled, Phase 3 studies evaluated finerenone added to a maximally tolerated dose of an angiotensin-converting enzyme inhibitor or an angiotensin II receptor blocker. Over >2 years of treatment, finerenone was associated with a significant reduction in composite endpoints of renal and cardiovascular outcomes versus placebo. Esaxerenone or apararenone have both shown significant improvements in albuminuria versus placebo. In general, nsMRAs were well tolerated. Hyperkalaemia was the most notable treatment-related adverse event and could generally be managed through serum potassium monitoring and dose adjustments. The nsMRAs are now an important component of recommended treatment for CKD associated with T2D, providing a significant reduction in the risk of cardiorenal progression beyond what can be achieved with glucose and blood pressure control.

Treating Primary Aldosteronism-Induced Hypertension: Novel Approaches and Future Outlooks

Primary aldosteronism (PA) is the most common cause of secondary hypertension and is associated with increased morbidity and mortality when compared with blood pressure-matched cases of primary hypertension. Current limitations in patient care stem from delayed recognition of the condition, limited access to key diagnostic procedures, and lack of a definitive therapy option for nonsurgical candidates. However, several recent advances have the potential to address these barriers to optimal care. From a diagnostic perspective, machine-learning algorithms have shown promise in the prediction of PA subtypes, while the development of noninvasive alternatives to adrenal vein sampling (including molecular positron emission tomography imaging) has made accurate localization of functioning adrenal nodules possible. In parallel, more selective approaches to targeting the causative aldosterone-producing adrenal adenoma/nodule (APA/APN) have emerged with the advent of partial adrenalectomy or precision ablation. Additionally, the development of novel pharmacological agents may help to mitigate off-target effects of aldosterone and improve clinical efficacy and outcomes. Here, we consider how each of these innovations might change our approach to the patient with PA, to allow more tailored investigation and treatment plans, with corresponding improvement in clinical outcomes and resource utilization, for this highly prevalent disorder.

Population pharmacokinetics of esaxerenone, a novel non-steroidal mineralocorticoid receptor blocker, in patients with essential hypertension, patients with diabetic nephropathy, and healthy volunteers

OBJECTIVES

Esaxerenone is a novel, non-steroidal mineralocorticoid receptor (MR) blocker with improved selectivity and affinity for MR. The objectives of this study were to model the population pharmacokinetics of esaxerenone in a diverse population and to evaluate the effect of covariates on pharmacokinetics parameters.

METHODS

A total of 8263 plasma esaxerenone concentrations from 166 healthy volunteers, 1097 hypertensive patients and 360 patients with diabetic nephropathy were pooled. A three-compartment model with sequential zero- and first-order absorption was used to describe the time-courses of plasma esaxerenone following single and multiple doses once daily for up to 12 weeks. Covariate effects were estimated using the full covariate modeling approach. Clinical relevance of covariates was ascertained using tornado plots.

RESULTS

Esaxerenone was estimated to have high bioavailability (85.3%), low clearance (3.28 L/h) and relatively large distribution volume at steady state (94.8 L). Body weight (-26 to +36%) and coadministration of itraconazole (+64%) or rifampicin (-68%) were associated with a greater influence on esaxerenone exposure.

CONCLUSIONS

The most influential covariates on esaxerenone exposure were coadministrations of itraconazole and rifampicin, followed by body weight. The clinical relevance of effects of renal impairment, mild to moderate hepatic impairment, and age is limited.

Future treatments in hypertension: Can we meet the unmet needs of patients?

The prevalence of arterial hypertension is approximately 47% in the United States and 55% in Europe. Multiple different medical therapies are used to treat hypertension including diuretics, beta blockers, calcium channel blockers, angiotensin receptor blockers, angiotensin converting enzyme inhibitors, alpha blockers, central acting alpha receptor agonists, neprilysin inhibitors and vasodilators. However, despite the numerous number of medications, the prevalence of hypertension is on the rise, a considerable proportion of the hypertensive population is resistant to these therapeutic modalities and a definitive cure is not possible with the current treatment approaches. Therefore, there is a need for novel therapeutic strategies to provide better treatment and control of hypertension. In this review, our aim is to describe the latest developments in the treatment of hypertension including novel medication classes, gene therapies and RNA-based modalities.

Aldosterone and cardiovascular diseases

Aldosterone's role in the kidney and its pathophysiologic actions in hypertension are well known. However, its role or that of its receptor [minieralocorticoid receptor (MR)] in other cardiovascular (CV) disease are less well described. To identify their potential roles in six CV conditions (heart failure, myocardial infarction, atrial fibrillation, stroke, atherosclerosis, and thrombosis), we assessed these associations in the following four areas: (i) mechanistic studies in rodents and humans; (ii) pre-clinical studies of MR antagonists; (iii) clinical trials of MR antagonists; and (iv) genetics. The data were acquired from an online search of the National Library of Medicine using the PubMed search engine from January 2011 through June 2021. There were 3702 publications identified with 200 publications meeting our inclusion and exclusion criteria. Data strongly supported an association between heart failure and dysregulated aldosterone/MR. This association is not surprising given aldosterone/MR's prominent role in regulating sodium/volume homeostasis. Atrial fibrillation and myocardial infarction are also associated with dysregulated aldosterone/MR, but less strongly. For the most part, the data were insufficient to determine whether there was a relationship between atherosclerosis, stroke, or thrombosis and aldosterone/MR dysregulation. This review clearly documented an expanding role for aldosterone/MR's dysregulation in CV diseases beyond hypertension. How expansive it might be is limited by the currently available data. It is anticipated that with an increased focus on aldosterone/MR's potential roles in these diseases, additional clinical and pre-clinical data will clarify these relationships, thereby, opening approaches to use modulators of aldosterone/MR's action to more precisely treat these CV conditions.

Fluid homeostasis induced by sodium-glucose cotransporter 2 inhibitors: novel insight for better cardio-renal outcomes in chronic kidney disease

Hypertension in chronic kidney disease (CKD) patients is a risk factor for end-stage renal disease, cardiovascular events, and mortality. Thus, the prevention and appropriate management of hypertension in these patients are essential strategies for better cardio-renal outcomes. In this review, we show novel risk factors for hypertension with CKD, several promising prognostic markers and treatment for cardio-renal outcomes. Of note, the clinical use of sodium-glucose cotransporter 2 (SGLT2) inhibitors has recently expanded to non-diabetic patients with CKD and heart failure as well as diabetic patients. SGLT2 inhibitors have an antihypertensive effect, but are also associated with a low risk of hypotension. This unique mechanism of blood pressure regulation by SGLT2 inhibitors may partially depend on body fluid homeostasis, which is mediated by the autoregulation property between "accelerator" (diuretic action) and "brake" (increase in anti-diuretic hormone vasopressin and fluid intake). Mineralocorticoid receptor (MR) blockers are used in the treatment of essential hypertension and hyperaldosteronism. Recently, a new MR blocker, finerenone, has been launched as a treatment for CKD with type 2 diabetes. These advances in relation to hypertension in CKD may contribute to the reduction of renal and cardiovascular events.

Potential Impact of Non-Steroidal Mineralocorticoid Receptor Antagonists in Cardiovascular Disease

Inappropriate mineralocorticoid receptor (MR) activation in different cardiovascular cell types has deleterious effects on cardiac remodeling and function. Therefore, MR inhibition is a crucial pharmacological strategy to overcome cardiovascular dysfunction. Despite efficient blockade of MR with steroidal MR antagonists (MRAs), their clinical application is unsatisfactory due to the adverse effects. Newer non-steroidal MRAs with greater potency could be suitable for clinical application, especially in patients with type 2 diabetes mellitus and chronic kidney disease. Although clinical evidence has shown the beneficial effects of non-steroidal MRAs on cardiovascular outcomes in patients with heart failure with reduced ejection fraction, clinical trials are ongoing to evaluate the efficacy of heart failure with preserved ejection fraction. Therefore, comparative pharmacological characterization of non-steroidal MRAs over classic steroidal MRAs is crucial. Here, we summarize the pre-clinical evidence of non-steroidal MRAs, which suggests an improvement in cardiac dysfunction, as well as the underlying molecular mechanisms in animal models mimicking different clinical conditions. In addition, we discuss up-to-date information from clinical trials regarding the beneficial effects of non-steroidal MRAs on meaningful cardiovascular outcomes. Both pre-clinical and clinical evidence support treatment with non-steroidal MRAs in patients with cardiovascular disease.

Clinical effect of nonsteroidal mineralocorticoid receptor (MR) antagonists in the treatment of diabetic kidney disease: expectations as a new therapeutic strategy

Diabetes mellitus is the main cause of chronic kidney disease (CKD) in Japan and worldwide. Although angiotensin-converting enzyme (ACE) inhibitors and angiotensin II type 1 receptor blockers (ARBs) are basic drugs for the treatment of CKD with diabetes (diabetic kidney disease, DKD) with albuminuria and/or proteinuria, it has also become clear that the use of an ACE inhibitor or ARB alone is not fully sufficient. We have previously reported the clinical effects of mineralocorticoid receptor (MR) antagonists and recommended their use in addition to renin-angiotensin system inhibitors. Recently, new types of nonsteroidal MR antagonists have been developed, and the results of a large-scale study are expected. Nonsteroidal MR antagonists are distributed in the heart, lungs, liver, and kidneys when administered orally and are characterized by their equivalent distribution between the heart (nonepithelial tissue) and kidneys (epithelial tissue). We summarize the latest evidence regarding the use of nonsteroidal MR antagonists in the treatment of DKD. Hyperkalemia and renal dysfunction are frequent during MR antagonist treatment. However, with careful and combined monitoring of these two conditions, the effectiveness of MR antagonists will not be diminished; conversely, it is apparent that patients at such risk will benefit more from the addition of an MR antagonist to the treatment regimen. The most important measure against hyperkalemia is the regular monitoring of serum potassium levels and renal function. The safest and most reliable measure against hyperkalemia is the combined use of a new oral potassium adsorbent that has high potassium selectivity and few side effects. In DKD treatment, it is important to continue using MR antagonists without interruption as much as possible.

The Time to Reconsider Mineralocorticoid Receptor Blocking Strategy: Arrival of Nonsteroidal Mineralocorticoid Receptor Blockers

PURPOSE OF REVIEW

The study aims to verify the advantages of nonsteroidal mineralocorticoid receptor blockers (MRBs) in the management of hypertension and cardiovascular and renal diseases, comparing with conventional MRBs.

RECENT FINDINGS

Based on the unique structures, the nonsteroidal MRBs have higher selectivity for mineralocorticoid receptors (MRs) and show no agonist activity for major steroid hormone receptors in contrast to steroidal MRBs. Today, there are two nonsteroidal MRBs, esaxerenone and finerenone, which completed phase 3 clinical trials. Series of clinical trials have shown that both agents achieve similar MR blockade with smaller doses as compared with steroidal MRBs, but have no off-target side effect such as gynecomastia. Esaxerenone has persistent blood pressure-lowering effects in various hypertensive populations, including essential hypertension and those with diabetes and/or chronic kidney disease, while finerenone has demonstrated reduction of the cardiovascular risk rather than blood pressure in patients with diabetes and chronic kidney disease. Nonsteroidal MRBs are a more refined agent which contributes to appropriate MR blocking with minimized unpleasant adverse effects.

Clinical Pharmacokinetics and Pharmacodynamics of Esaxerenone, a Novel Mineralocorticoid Receptor Antagonist: A Review

Esaxerenone is a selective, nonsteroidal, high-affinity mineralocorticoid receptor antagonist recently approved in Japan for the treatment of hypertension. It has high oral biovailability, a large volume of distribution, and is primarly metabolized in liver and excreted in bile. Esaxerenone is an efficient antihypertensive, whether given alone or as add-on therapy. The antihypertensive effect is accompanied by renoprotective action, which is being further investigated in current clinical trials. Due to its relatively long half-life and high affinity for the mineralocorticoid receptor, esaxerenone is administered once daily and in low absolute doses. The safety of esaxerenone is considerable, since hyperkalemia is not frequent and, when it does appear, not sustained. Endocrine adverse events, which frequently occur with steroidal mineralocorticoid receptor antagonists, are extremely rare with esaxerenone. Although the risk of clinically significant drug-drug interactions is not high, esaxerenone treatment should start with low doses, with subsequent titration to achieve the optimal clinical effect, all while monitoring serum potassium and paying attention to concomitant therapy with drugs that may induce or inhibit esaxerenone metabolism. This review article offers comprehensive information about the pharmacodynamics and pharmacokinetics of esaxerenone in humans, which should help clinicians to more precisely tailor esaxerenone dosing regimens to their patients.

Differentiation between emerging non-steroidal and established steroidal mineralocorticoid receptor antagonists: head-to-head comparisons of pharmacological and clinical characteristics

INTRODUCTION

Mineralocorticoid receptor (MR) antagonists (MRAs) provide cardiorenal protection. However steroidal MRAs might induce hyperkalemia and sex hormone-related adverse effects. Several novel non-steroidal MRAs are being developed that are highly selective for the MR and may have an improved safety profile.

AREAS COVERED

This narrative review summarizes data from head-to-head comparisons of emerging non-steroidal MRAs with older steroidal MRAs, including pharmacological characteristics, pharmacokinetic properties, clinical outcomes, and safety, and highlights similarities and differences between emerging agents and established steroidal MRAs.

EXPERT OPINION

Head-to-head comparisons in phase 2 trials suggest that the new non-steroidal MRAs exhibit at least equivalent efficacy to steroidal MRAs but may have a better safety profile in patients with heart failure and/or kidney disease. When also taking into account data from recent phase 3 placebo-controlled trials, these novel non-steroidal MRAs have the potential to provide a cardiorenal benefit above that of current optimized standard-of-care treatment in a high-risk population with reduced renal function, and with a lower risk of hyperkalemia. To optimize therapy, further research is needed to clarify the molecular differences in the mode of action of non-steroidal MRAs versus steroidal MRAs, and biomarkers that are predictive of MRA response need to be identified and validated.

New Drugs and Interventional Strategies for the Management of Hypertension

Essential hypertension is an important cause of cardiovascular morbidity and mortality worldwide with significant clinical and economic implications. The field of antihypertensive treatment already numbers numerous agents and classes of drugs. However, patients are still developing uncontrolled hypertension. Hence there is a continuous need for novel agents with good tolerability. Advances in this field are focusing both on pharmacotherapy, with the developments in traditional and non-traditional targets, as well as interventional techniques such as renal denervation and baroreflex activation therapy. It is likely that future strategies may involve a tailored approach to the individual patient, with genetic modulation playing a key role.

Mineralocorticoid Receptor Antagonists in Diabetic Kidney Disease

Diabetes mellitus is a global health issue and main cause of chronic kidney disease. Both diseases are also linked through high cardiovascular morbidity and mortality. Diabetic kidney disease (DKD) is present in up to 40% of diabetic patients; therefore, prevention and treatment of DKD are of utmost importance. Much research has been dedicated to the optimization of DKD treatment. In the last few years, mineralocorticoid receptor antagonists (MRA) have experienced a renaissance in this field with the development of non-steroidal MRA. Steroidal MRA have known cardiorenal benefits, but their use is limited by side effects, especially hyperkalemia. Non-steroidal MRA still block the damaging effects of mineralocorticoid receptor overactivation (extracellular fluid volume expansion, inflammation, fibrosis), but with fewer side effects (hormonal, hyperkalemia) than steroidal MRA. This review article summarizes the current knowledge and newer research conducted on MRA in DKD.

[Pharmacological profile, clinical efficacy, and safety of esaxerenone (Minnebro® tablets 1.25 mg, 2.5 mg, 5 mg)]

Esaxerenone is a novel non-steroidal mineralocorticoid receptor antagonisit (MR blocker), whose unique binding to the MR-ligand domain yields a stronger MR antagonistic effect and higher selectivity than existing MR antagonisits. Esaxerenone was approved for the treatment of hypertension in Japan in January 2019. Esaxerenone suppresses the reduction of urinary Na+/K+ ratio in adrenalectomized rats and blood pressure increase, proteinuria, and renal tissue lesions in salt-sensitive hypertensive rats-all in a dose-dependent manner. Esaxerenone is rapidly absorbed and reaches intracellular targets because of its high membrane permeability, exhibits high bioavailability with small interindividual exposure variation, and is metabolized via several pathways (e.g., oxidation, glucuronidation, and hydrolysis), which is associated with low drug-drug interaction risk. As esaxerenone is slightly excreted into urine, its exposure is similar between elderly and non-elderly patients, and between patients with normal and moderately deteriorated renal function. Given its 19-hour half-life, once-daily administration would have a sustainable antihypertensive effect. The ESAX-HTN phase 3 study demonstrated the non-inferiority of esaxerenone's antihypertensive effect versus that of eplerenone in essential hypertension. Another study showed a stable antihypertensive effect for 52 weeks as monotherapy or combination therapy. In hypertensive patients with moderate impairment or both type 2 diabetes and albuminuria treated with a renin-angiotensin system inhibitor, esaxerenone elicited a stable antihypertensive effect and manageable hyperkalemia incidence with titration from a low dose and monitoring including serum potassium. Thus, with careful monitoring of serum potassium, esaxerenone can be administered to patients with moderate renal impairment or both diabetes and albuminuria.

Esaxerenone, a novel nonsteroidal mineralocorticoid receptor blocker (MRB) in hypertension and chronic kidney disease

The steroidal mineralocorticoid receptor (MR) antagonists, spironolactone and eplerenone, decrease blood pressure, and attenuate the progression of chronic kidney disease (CKD). However, their use is limited by the fear of inducing hyperkalemia, gynecomastia, impotence, and amenorrhea. Esaxerenone is a novel nonsteroidal MR blocker (MRB) that has been recently developed. In vitro studies have revealed that esaxerenone has a high potency and selectivity for MR compared with spironolactone and eplerenone. Further studies have shown that esaxerenone elicits a strong blood pressure-lowering effect in hypertensive animals. Following the results from phase III clinical trials that esaxerenone is an effective and well-tolerated MRB in Japanese hypertensive patients, esaxerenone became clinically available in Japan from May 2019 for hypertensive patients. Thus, esaxerenone is a promising treatment option for patients with hypertension. In addition, both preclinical studies and phase II clinical trials have shown that esaxerenone elicits renoprotection independent of its antihypertensive effect. Recently, a phase III clinical trial (ESAX-DN study) has also demonstrated the safety and efficacy of esaxerenone in patients with type 2 diabetes and microalbuminuria. These data support future clinical development of esaxerenone for the treatment of renal disease.

Drug-Drug Interaction Risk Assessment of Esaxerenone as a Perpetrator by In Vitro Studies and Static and Physiologically Based Pharmacokinetic Models

Esaxerenone (CS-3150) is a novel, oral, nonsteroidal, selective mineralocorticoid receptor blocker approved for the treatment of hypertension in Japan. Here, the drug-drug interaction (DDI) potential of esaxerenone was evaluated in vitro, and its impact in clinical practice was estimated. Esaxerenone exhibited time-dependent inhibition and induction of CYP3A. When the clinical impacts of esaxerenone on the inhibition and induction of CYP3A were estimated separately by using a mechanistic static model, the predicted area under the curve ratios (AUCRs) of midazolam, a typical CYP3A substrate, were 1.80 and 0.31, respectively, suggesting that the DDI potential of esaxerenone cannot be neglected. Because it was suggested that DDIs mainly occur in the intestine, predictions using concentration-time profiles in each segment of the gastrointestinal tract were performed with GastroPlus, a physiologically based pharmacokinetic (PBPK) modeling software. The predicted AUCR of midazolam was approximately 1.2, which is close to that in a clinical study, despite the difficulty of predicting DDIs for compounds with both inhibition and induction effects. When only inhibition or induction was incorporated into a model, the AUCR of midazolam changed depending on the dosing period and dose level of esaxerenone and the timing of midazolam administration. However, the AUCR calculated by incorporating both effects remained almost constant. This study shows the ability of PBPK models to simulate weak DDIs via intestinal CYP3A and that esaxerenone has low DDI potential as a perpetrator because of the offset of inhibition and induction. SIGNIFICANCE STATEMENT: Weak CYP3A inhibition and/or induction sometimes cause DDIs in the intestine but not the liver. Because strong inhibitors maximally inhibit intestinal CYP3A, the predictability of weak DDIs in the intestine should be evaluated further. Here, we simulate the DDIs of esaxerenone as a perpetrator by using physiologically based pharmacokinetic modeling focusing on the intestine and offset of inhibition and induction.

Synergistic reduction in albuminuria in type 2 diabetic mice by esaxerenone (CS-3150), a novel nonsteroidal selective mineralocorticoid receptor blocker, combined with an angiotensin II receptor blocker

Esaxerenone is a novel selective mineralocorticoid receptor (MR) blocker that was recently approved in Japan to treat hypertension. In phase II and III studies, esaxerenone plus a renin–angiotensin system inhibitor markedly reduced the urinary albumin-to-creatinine ratio (UACR) in hypertensive patients with diabetic nephropathy. To evaluate a direct renoprotective effect by MR blockade independent of an antihypertensive effect in the context of diabetic nephropathy, esaxerenone (3 mg/kg), olmesartan (an angiotensin II receptor blocker; 1 mg/kg), or both were orally administered to KK-Ay mice, a type 2 diabetes model, once daily for 56 days. Urinary albumin (Ualb), UACR, and markers, such as podocalyxin, monocyte chemoattractant protein-1 (MCP-1), and 8-hydroxy-2′-deoxyguanosine (8-OHdG), were measured, along with systolic blood pressure (SBP), fasting blood glucose, and serum K⁺ levels. Prior to the initiation of drug administration, KK-Ay mice showed higher blood glucose, insulin, Ualb excretion, and UACR levels than C57BL/6 J mice, a nondiabetic control, indicating the development of diabetic renal injury. Combined treatment with esaxerenone and olmesartan significantly reduced the change in UACR from baseline compared with the change associated with vehicle at week 8 (−1.750 vs. 0.339 g/gCre; P < 0.002) and significantly inhibited the change in Ualb from baseline compared with the change associated with vehicle at week 8 (P < 0.002). The combination treatment also reduced urinary excretion of podocalyxin and MCP-1, but did not influence 8-OHdG excretion, SBP, blood glucose, or serum K⁺ levels. Overall, esaxerenone plus olmesartan treatment ameliorated diabetic nephropathy in KK-Ay mice without affecting SBP, suggesting that the renoprotective effects of esaxerenone could be exerted independently of its antihypertensive effect.

Recent advances in the management of secondary hypertension: chronic kidney disease

Hypertension in chronic kidney disease (CKD) is the most commonly observed comorbidity and is a risk factor for end-stage renal disease (ESRD) as well as cardiovascular disease (CVD) and mortality. Therefore, suitable blood pressure (BP) control in CKD patients is very important in preventing both CVD and ESRD. We herein describe the recommendations of target BP and the pharmacological drug options from the evidence-based clinical practice guidelines for CKD in 2018 by the Japanese Society of Nephrology (JSN CKD 2018) and recent advances in the management of hypertension in CKD, including sodium-glucose cotransporter (SGLT) 2 inhibitors, mineralocorticoid receptor blockers, and renal denervation. In particular, SGLT2 inhibitors are a new class of "antihypertensive drugs" that have a homeostatic mechanism that regulates body fluid volume in addition to diuretic action, which may be closely associated with their cardiorenal protective properties.

Mineralocorticoid Receptor Blockers: Novel Selective Nonsteroidal Mineralocorticoid Receptor Antagonists

PURPOSE OF REVIEW

Recently, nonsteroidal mineralocorticoid receptor (MR) antagonists (MRAs), which have been proposed to be called MR blockers (MRBs), have become available for clinical use, but their clinical role is unknown. We reviewed the clinical roles of MRAs and MRBs based on previous knowledge and as demonstrated in representative clinical trials.

RECENT FINDINGS

Steroidal MRAs, such as spironolactone and eplerenone, inhibit the action of aldosterone and cortisol in MRs expressed in several organs and cell types, and accumulating clinical studies have revealed that they exert hypotensive and cardiorenal protective effects. Recently, MRBs, including finerenone and esaxerenone, have been developed and are expected to lower the risk of hyperkalemia, which is common when steroidal MRAs are used. Although the differences between MRAs and MRBs in clinical practice have not yet been established, further studies in this field are expected to broaden our understanding. MRBs exert antihypertensive and cardiorenal protective effects, and their potency is thought to be far superior to that of MRAs, because MRBs have both strong MR inhibitory action and high selectivity. Thus, MRBs could be a promising agent for the treatment of hypertension and cardiorenal, cerebral, and metabolic disorders.

A Patient with Bilateral Primary Aldosteronism Refractory to Oral Eplerenone Who Responded to Esaxerenone with Increased Renin Activity

Patient: Male, 45-year-old

Final Diagnosis: Bilateral primary aldosteronism

Symptoms: Hypertension

Medication: Mineralocorticoid receptor blocker

Clinical Procedure: Segmental adrenal venous sampling and medication

Specialty: Cardiology

Absolute Bioavailability of Esaxerenone and Food Effects on its Pharmacokinetics After a Single Oral Dose in Healthy Japanese Subjects: An Open-Label Crossover Study

Introduction

To investigate the absolute bioavailability of esaxerenone and the effects of food on its pharmacokinetics (PK) after a single oral dose in healthy Japanese subjects.

Methods

Twenty-four Japanese males aged 20–45 years were randomised to six groups (each n = 4) in this single-centre, open-label, three-way, three-period crossover study. Esaxerenone (5 mg) was administered in the fasting state as a single oral dose, single intravenous infusion over 1 h, or in the postprandial state as a single oral dose. Plasma samples were taken before and during the 96 h after drug administration. Drug concentrations were measured using liquid chromatography-tandem mass spectrometry. PK parameters were calculated using noncompartmental analysis, and safety was assessed.

Results

After fasting intravenous administration, total body clearance was 3.69 L h⁻¹ and volume of distribution was 92.7 L. The plasma concentration–time profile of esaxerenone was similar after fasting and postprandial administration. Absolute bioavailability of a single oral 5-mg dose of esaxerenone was 89.0% in the fasting state and 90.8% postprandially. Point estimates (1.010 and 1.019, respectively) and 90% confidence intervals for geometric least squares mean peak plasma concentrations and area under the plasma concentration–time curve ratios after postprandial versus fasting oral esaxerenone were within the prespecified range (0.80, 1.25). No severe adverse events occurred throughout the study.

Conclusions

Esaxerenone has a high absolute bioavailability of approximately 90% and food has no effect on esaxerenone PK after a single oral dose of 5 mg in healthy Japanese subjects. Additionally, no safety concerns were identified.

Clinical Trial Registration

JapicCTI No. 163452.

Funding

Daiichi Sankyo Co., Ltd.

New mineralocorticoid receptor antagonists: update on their use in chronic kidney disease and heart failure

Aldosterone is a mineralocorticoid hormone with a well-known effect on the renal tubule leading to water retention and potassium reabsorption. Other major effects of the hormone include the induction of proinflammatory activity that leads to progressive fibrotic damage of the target organs, heart and kidney. Blocking the aldosterone receptor therefore represents an important pharmacological strategy to avoid the clinical conditions deriving from heart failure (CHF) and chronic kidney disease (CKD). However, steroidal mineralocorticoid receptor antagonists (MRA) have a low safety profile, especially in CKD patients due to the high incidence of hyperkalemia. A new generation of nonsteroidal MRA has recently been developed to obtain a selective receptor block avoiding side-effects like hyperkalemia and thereby making the drugs suitable for administration to CKD patients. This review summarizes the results of published preclinical and clinical studies on the nonsteroidal MRA, apararenone esaxerenone and finerenone. The trials showed a better safety profile with maintained drug efficacy compared with steroidal MRA. For this reason, nonsteroidal MRA represent an interesting new therapeutic approach for the prevention of CHF and CKD progression. Some basic research findings also yielded interesting results in acute clinical settings such as myocardial infarction and acute kidney injury.

Effect of a novel nonsteroidal selective mineralocorticoid receptor antagonist, esaxerenone (CS-3150), on blood pressure and renal injury in high salt-treated type 2 diabetic mice

Although beneficial antihypertensive and antialbuminuric effects of steroidal mineralocorticoid receptor (MR) antagonists have been shown, the use of these drugs has been clinically limited in diabetic kidney disease (DKD) because of the high incidence of side effects. Here, we aimed to examine the effect of a novel nonsteroidal selective mineralocorticoid receptor antagonist, esaxerenone, on blood pressure and renal injury in high salt-treated type 2 diabetic KK-A^y mice, a model of human hypertensive DKD. KK-A^y mice were treated with a normal salt diet (NS: 0.3% NaCl, n = 5), high salt diet (HS: 4% NaCl, n = 8), HS + esaxerenone (1 mg/kg/day, p.o., n = 8), or HS + spironolactone, a steroidal non-selective MR antagonist (20 mg/kg/day, p.o., n = 7) for 8 weeks. Renal tissue oxidative stress was evaluated by dihydroethidium florescence intensity. HS-treated diabetic KK-A^y mice showed higher blood pressure and severe albuminuria, glomerular injury, tubulointerstitial fibrosis, renal inflammation, and oxidative stress than NS-treated diabetic KK-A^y mice. Treatment with esaxerenone or spironolactone decreased blood pressure to a similar extent in HS-treated KK-A^y mice. Conversely, esaxerenone elicited a greater attenuation of albuminuria, glomerular injury, tubulointerstitial fibrosis, and renal inflammation than spironolactone, which were associated with reduction in renal oxidative stress. These data indicate for the first time that a nonsteroidal MR antagonist elicits renoprotective effects in DKD mice.

Comprehensive preclinical pharmacokinetic evaluations of trastuzumab deruxtecan (DS-8201a), a HER2-targeting antibody-drug conjugate, in cynomolgus monkeys

Trastuzumab deruxtecan (DS-8201a) is an antibody-drug conjugate (ADC) composed of a monoclonal antibody targeting human epidermal growth factor receptor 2 (HER2) conjugated to a topoisomerase I inhibitor (DXd) at a drug-to-antibody ratio (DAR) of 7-8. Here, we examined the pharmacokinetic (PK) profiles of DS-8201a and DXd in cynomolgus monkeys, a cross-reactive species. Following intravenous (iv) administration of DS-8201a, the linker was stable in plasma, and systemic DXd exposure was low. DXd was rapidly cleared following iv dosing. Biodistribution studies revealed that intact DS-8201a was present mostly in the blood without tissue-specific retention. The major pathway of excretion for DXd was the faecal route following iv administration of radiolabelled DS-8201a. The only detectable metabolite in the urine and faeces was unmetabolized DXd. DXd is a substrate of organic anion transporting polypeptides, P-gp, and breast cancer resistance protein. In conclusion, the stable linker in circulation and the high clearance of DXd upon release resulted in the low systemic exposure to DXd. Furthermore, the minimal tissue-specific retention and rapid excretion of DXd into faeces as its unmetabolized form with potentially limited impact on drug - drug interaction as a victim were also critical elements of the PK profile of DS-8201a.

Effects of the novel nonsteroidal mineralocorticoid receptor blocker, esaxerenone (CS-3150), on blood pressure and urinary angiotensinogen in low-renin Dahl salt-sensitive hypertensive rats

Herein, we studied the effects of the novel nonsteroidal selective mineralocorticoid receptor (MR) blocker, esaxerenone, on blood pressure and renal injury in Dahl salt-sensitive (DSS) rats. We also monitored intact urinary and total angiotensinogen (AGT). DSS rats were given a normal salt diet (NS: 0.4% NaCl, n = 10), a high-salt diet (HS: 8% NaCl, n = 10), HS + esaxerenone (1 mg/kg/day, p.o., n = 10), or HS + losartan (angiotensin II receptor blocker, 10 mg/kg/day, p.o., n = 10) for 6 weeks. Glomerular and tubulointerstitial tissues were obtained via a laser capture method. HS-treated DSS rats developed hypertension, albuminuria, and glomerular injury, which were associated with increased glomerular desmin staining and reduced mRNA levels of glomerular podocin and nephrin. HS-treated DSS rats also showed tubulointerstitial fibrosis with an increase in renal oxidative stress (4-hydroxynonenal staining). The urinary ((total AGT-intact AGT)/intact AGT) ratio, an indicator of intrarenal renin activity, was significantly suppressed in HS-treated DSS rats. Treatment with esaxerenone significantly decreased blood pressure, while losartan did not. Furthermore, esaxerenone attenuated the development of albuminuria, glomerular injury, and tubulointerstitial fibrosis more than losartan did, and this effect was associated with reduced renal oxidative stress. These data indicate that esaxerenone has antihypertensive and renal protective effects in salt-dependent hypertensive mice with suppressed intrarenal renin activity, as indicated by low levels of the urinary (total AGT-intact AGT)/intact AGT ratio.

Pharmacokinetics, Metabolism, and Excretion of [14C]Esaxerenone, a Novel Mineralocorticoid Receptor Blocker in Humans

Esaxerenone (CS-3150) is a novel, nonsteroidal, selective mineralocorticoid receptor blocker. The absorption, metabolism, distribution, and excretion of esaxerenone were assessed in in vitro studies and in a clinical study, where [¹⁴C]esaxerenone (150 μCi/20 mg) was administered orally to six healthy male subjects. The plasma concentrations of esaxerenone and its metabolites (M4, M11, and M1) were measured using liquid chromatography-tandem mass spectrometry. The recovery of radioactivity was 92.5%, with 38.5% and 54.0% excreted in the urine and feces, respectively. The half-life of radioactivity in blood and plasma was approximately 30 hours, similar to that of the unchanged form in plasma. The blood-to-plasma ratio was 0.628, demonstrating low partitioning to blood components. In plasma, esaxerenone was the most abundant moiety (40.8%), followed by O-glucuronide (21.4%; M4), acyl-glucuronide of amide-bond hydrolysate (8.0%; M11), and the deshydroxyethyl form (1.7%; M1). In vitro studies showed that esaxerenone was a substrate of CYP3A and multiple UDP-glucuronosyltransferase isoforms. Oxidation contributed approximately 30% to its clearance, as indicated by the excretion ratio of oxidized metabolites into urine and feces. Caco-2 studies showed that esaxerenone was a substrate of P-glycoprotein and breast cancer resistance protein; however, the excretion ratios of the unchanged form in the feces and urine were 18.7% and 1.6%, respectively, indicating that these transporters were not important for the absorption and elimination of esaxerenone. Low urinary excretion of esaxerenone suggested that the plasma exposure of esaxerenone was not affected by renal dysfunction. Multiple elimination pathways including oxidation, glucuronidation, and hydrolysis, and the low contribution of transporters, indicated limited drug-drug interaction potential.

Identification of Morpholino-2H-pyrido[3,2-b][1,4]oxazin-3(4H)-ones as Nonsteroidal Mineralocorticoid Antagonists

A novel series of morpholine-based nonsteroidal mineralocorticoid receptor antagonists is reported. Starting from a pyrrolidine HTS hit 9 that possessed modest potency but excellect selectivity versus related nuclear hormone receptors, a series of libraries led to identification of morpholine lead 10. After further optimization, cis disubstituted morpholine 22 was discovered, which showed a 45-fold boost in binding affinity and corresponding functional potency compared to 13. While 22 had high clearance in rat, it provided sufficient exposure at high doses to favorably assess in vivo efficacy (increased urinary Na⁺/K⁺ ratio) and safety. In contrast to rat, the dog and human MetID and PK profiles of 22 were adequate, suggesting that it could be suitable as a potential clinical asset.