Effect of the Nonsteroidal Mineralocorticoid Receptor Blocker, Esaxerenone, on Nocturnal Hypertension: A Post Hoc Analysis of the ESAX-HTN Study.

BACKGROUND: Nocturnal hypertension is an important phenotype of abnormal diurnal blood pressure (BP) variability and a known risk marker for target organ damage and cardiovascular events. This study aimed to assess the differential BP-lowering effects of esaxerenone vs. eplerenone on nocturnal BP in hypertensive patients with different nocturnal dipping patterns. METHODS: This was a post hoc analysis of the "Esaxerenone (CS-3150) Compared to Eplerenone in Patients with Essential Hypertension" study (NCT02890173), which was a phase 3, multicenter, randomized, controlled, double-blind, parallel-group clinical study conducted in Japan. Ambulatory BP monitoring data were collected. RESULTS: Patients (n = 1,001) were randomized to esaxerenone 2.5 mg/day (n = 331) or 5 mg/day (n = 338), or eplerenone 50 mg/day (n = 332). Reductions in nighttime systolic BP (95% confidence interval) were significantly greater with 2.5 and 5 mg/day esaxerenone vs. eplerenone (-2.6 [-5.0, -0.2] and -6.4 mm Hg [-8.8, -4.0], respectively). Esaxerenone significantly reduced nighttime BP from baseline compared with eplerenone in non-dippers with previously uncontrolled BP. In addition, esaxerenone did not markedly alter nighttime BP in extreme dipper patients. In the esaxerenone 5 mg/day group, esaxerenone-induced decreases in nighttime BP were greater than eplerenone-induced decreases in older patients. CONCLUSIONS: Esaxerenone may be an effective treatment option for nocturnal hypertension, especially in older patients and those with a non-dipper pattern of nocturnal BP.

[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.

Double-Blind Randomized Phase 3 Study Comparing Esaxerenone (CS-3150) and Eplerenone in Patients With Essential Hypertension (ESAX-HTN Study).

Mineralocorticoid receptors (MRs) are implicated in the pathology of hypertension. MR blockers are recommended for the treatment of salt-sensitive or resistant hypertension. However, use of currently available MR blockers is limited by adverse events. This phase 3 multicenter, randomized, double-blind study compared the efficacy and safety of esaxerenone, a new selective nonsteroidal MR blocker, at 2.5 and 5 mg/day and eplerenone 50 mg/day in Japanese patients with essential hypertension. After a 4-week washout period, 1001 eligible adults with hypertension were randomized evenly to esaxerenone 2.5 or 5 mg/day or eplerenone 50 mg/day treatments, taken orally once daily for 12 weeks. Primary end points were changes in sitting systolic or diastolic blood pressure (BP) from baseline at the end of treatment. Esaxerenone 2.5 mg/day was noninferior to eplerenone for reductions in sitting and 24-hour BP. Reductions in BP with esaxerenone 5 mg/day were significantly greater than those with esaxerenone 2.5 mg/day. Changes in diurnal BP showed persistent 24-hour antihypertensive effects in all treatment groups. The proportions of patients achieving target sitting BP (<140/90 mm Hg) were 31.5%, 41.2%, and 27.5% with esaxerenone 2.5 and 5 mg/day and eplerenone 50 mg/day, respectively. Incidences of adverse events (all mild or moderate) were similar across treatment groups. These results indicate that esaxerenone is an effective and well-tolerated MR blocker in Japanese patients with essential hypertension, with BP-lowering activity at least equivalent to eplerenone. Clinical Trial Registration- URL: http://www.clinicaltrials.gov. Unique identifier: NCT02890173.

'Crystal lattice engineering,' an approach to engineer protein crystal contacts by creating intermolecular symmetry: crystallization and structure determination of a mutant human RNase 1 with a hydrophobic interface of leucines.

A protein crystal lattice consists of surface contact regions, where the interactions of specific groups play a key role in stabilizing the regular arrangement of the protein molecules. In an attempt to control protein incorporation in a crystal lattice, a leucine zipper-like hydrophobic interface (comprising four leucine residues) was introduced into a helical region (helix 2) of the human pancreatic ribonuclease 1 (RNase 1) that was predicted to form a suitable crystallization interface. Although crystallization of wild-type RNase 1 has not yet been reported, the RNase 1 mutant having four leucines (4L-RNase 1) was successfully crystallized under several different conditions. The crystal structures were subsequently determined by X-ray crystallography by molecular replacement using the structure of bovine RNase A. The overall structure of 4L-RNase 1 is quite similar to that of the bovine RNase A, and the introduced leucine residues formed the designed crystal interface. To characterize the role of the introduced leucine residues in crystallization of RNase 1 further, the number of leucines was reduced to three or two (3L- and 2L-RNase 1, respectively). Both mutants crystallized and a similar hydrophobic interface as in 4L-RNase 1 was observed. A related approach to engineer crystal contacts at helix 3 of RNase 1 (N4L-RNase 1) was also evaluated. N4L-RNase 1 also successfully crystallized and formed the expected hydrophobic packing interface. These results suggest that appropriate introduction of a leucine zipper-like hydrophobic interface can promote intermolecular symmetry for more efficient protein crystallization in crystal lattice engineering efforts.