Disposition and metabolism of [14C] Sacubitril/Valsartan (formerly LCZ696) an angiotensin receptor neprilysin inhibitor, in healthy subjects

Transforming pediatric heart failure: Efficacy of low-dose sacubitril/valsartan

AIMS

Pediatric heart failure is a significant cause of illness and death in children. We aimed to assess sacubitril/valsartan's effectiveness and find the proper dosage for pediatric patients.

METHODS

Patients unresponsive to traditional medicines for at least 12 months prescribed sacubitril/valsartan from January 2020 to March 2023 were reviewed. The initial dose was 0.2 mg/kg bid, gradually increasing in 0.1 mg/kg increments. The target dose was determined based on blood pressure fluctuations at 70/50 mmHg. Clinical efficacy and quantity-effect relationship were evaluated using echocardiography, NT-proBNP, and the concentration of valsartan, sacubitril, sacubitrilat.

RESULTS

A total of 23 pediatric patients with dilated cardiomyopathy and advanced heart failure were enrolled. Mean sacubitril/valsartan dose was 1.84 mg/kg/day. After 6 months, LVEF increased significantly (38.09% to 45% at 3 months, 52% at 6 months; p < 0.001). LV size reduced to 4.4 cm (IQR, 4.1-5.2) and 4.5 cm (IQR, 4-5.1) at 3 and 6 months, respectively, from 4.6 cm (IQR, 4.2-5.6) at baseline (both P < 0.05). NT-proBNP levels reduced by 5.7 at 3 months (p < 0.05) and 5.38 at 6 months (p < 0.001). Sacubitrilat is the active form of Sacubitril. The highest concentration of sacubitrilat was observed at approximately 1.6 mg/kg. The maintenance dose correlated positively with time (p < 0.001) and valsartan/sacubitril concentration (p < 0.05).

CONCLUSION

Low dose sacubitril/valsartan is effective in children with heart failure, with dosage adjustments to avoid hypotension. Adjusted dosing can increase EF and reduce heart size, offering new possibilities for pediatric heart failure treatment.

Assessment of drug-drug interaction of dapagliflozin with LCZ696 based on an LC-MS/MS method

The co-administration of dapagliflozin (DPF) and sacubitril/valsartan (LCZ696) has emerged as a promising therapeutic approach for managing heart failure. Given that DPF and LCZ696 are substrates for P-glycoprotein, there is a plausible potential for drug-drug interactions when administered concomitantly. To investigate the pharmacokinetic changes when these drugs are co-administered, we have established and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method capable of simultaneously detecting DPF, LBQ657 (the active metabolite of sacubitril) and valsartan in rat plasma. This method has demonstrated selectivity, sensitivity, and accuracy. Drug-drug interactions were examined by the LC-MS/MS method. The mechanisms were investigated using everted intestinal sac models and Caco-2 cells. The results showed that DPF significantly increased the area under the curve (AUC(0-t)) (3,563.3 ± 651.7 vs. 7,146.5 ± 1,714.9 h μg/L) of LBQ657 (the active metabolite of sacubitril) and the AUC(0-t) (24,022.4 ± 6,774.3 vs. 55,728.3 ± 32,446.3 h μg/L) of valsartan after oral co-administration. Dapagliflozin significantly increased the amount of LBQ657 and valsartan in intestinal sacs by 1- and 1.25-fold at 2.25 h. Caco-2 cell uptake studies confirmed that P-glycoprotein is the transporter involved in this interaction. This finding enhances the understanding of drug-drug interactions in the treatment of heart failure and provides a guidence for clinical therapy.

Development and validation of a sensitive and simple LC-MS/MS method for simultaneous quantitation of valsartan, sacubitril and sacubitrilat in pediatric population

Pediatric heart failure (HF) is an important clinical disease with high hospitalization rates, morbidity, mortality and medical costs. Sacubitril/valsartan (also known as Entresto), was approved for the treatment of adult HF and is recently used in pediatrics. However, clinical therapy on children is more challenging than adults, and the pharmacokinetics of Entresto in children are still largely unknown and urgently needed. Herein, we aim to develop a simple and sensitive analytic method to monitor Entresto in pediatric patients, which is of great importance for individualized safe medication in children. Specifically, a liquid chromatography tandem mass spectrometry method for simultaneously quantification of valsartan, sacubitril and its bio-active metabolite sacubitrilat in human plasma has been developed and validated in pediatric patients. Plasma samples were pretreated with acetonitrile for protein precipitation. Elution was performed on X Select HSS T3 column (2.1 × 100 mm, 5 µm; Waters) column using an isocratic mobile phase process consisting of 0.1% formic acid aqueous solution and 0.1% formic acid acetonit rile with a total run time of 3.0 min. Valsartan-d3, sacubitrilin-d4 and sacubitrilat-d4 were used as the corresponding deuterium internal standards. According to the Bioanalytical Method Validation Guidance for Industry, the method was validated in the range of 0.5-5000 ng/mL. Intra- and inter-day accuracy of sacubitril,valsartan and sacubitrilat ranged from 93%- 108%, 98%- 109%, 91%- 102%, respectively, with relative standard deviation of precision ranging from 2.0% to 5.1%, 2.4%- 7.5%, 1,3%- 7.4%. The proposed method demonstrated good accuracy, precision and linearity. The matrix factors normalized by internal standard meet the acceptance criteria. The method was fully validated and applied in 39 children. Trough concentration of the three substances to be measured were: valsartan (11.3-938.0 ng/mL), sacubitril (0.5-395.5 ng/mL) and sacubitrilat (522.1-4890.0 ng/mL). Overall, this is the first study to simultaneously determined the plasma valsartan, sacubitril and sacubitrilat concentrations in children, which is believed to facilitate the clinical management of pediatric HF.

Pharmacokinetics and Pharmacodynamics of Sacubitril/Valsartan in Maintenance Hemodialysis Patients with Heart Failure

BACKGROUND

Heart failure (HF) is one of the main comorbidities in patients receiving maintenance hemodialysis (HD). Sacubitril/valsartan (SAC/VAL) is widely used in HF patients with reduced ejection fraction (HFrEF) or HF mid-range ejection fraction (HFmrEF). However, the pharmacokinetic (PK) and pharmacodynamic properties of SAC/VAL in HD patients with HF remain uncertain.

OBJECTIVES

This study aimed to analyze the efficacy and PK properties of SAC/VAL in HD patients with HFrEF or HFmrEF.

METHODS

HD patients with HFrEF or HFmrEF were treated with SAC/VAL 50 or 100 mg twice a day (BID) and the concentrations of valsartan and LBQ657 (active metabolite of SAC) were determined by high-performance liquid chromatography-tandem mass spectrometry during HD and on the days between HD sessions (interval days). N-terminal-pro B-type natriuretic peptide and high-sensitivity troponin T were measured, and left ventricular ejection fraction (LVEF) was evaluated by echocardiography.

RESULTS

The mean maximum plasma concentrations (Cmax) of LBQ657 and VAL on the interval days were 15.46 ± 6.01 and 2.57 ± 1.23 mg/L, respectively. Compared with previous values in patients with severe renal impairment and healthy volunteers, these levels both remained within the safe concentration ranges during treatment with SAC/VAL 100 mg BID. Moreover, SAC/VAL significantly improved LVEF in HD patients with HFrEF or HFmrEF (p < 0.05).

CONCLUSIONS

HD did not remove the SAC metabolite LBQ657 or VAL in patients with HF. However, SAC/VAL 100 mg BID was safe and effective in patients undergoing HD.

Angiotensin receptor-neprilysin inhibitor in patients with heart failure and chronic kidney disease

Despite significant advances in the management of heart failure with reduced ejection fraction (HFrEF), there remains an enormous health problem with high morbidity and mortality over the last few decades. The neprilysin inhibitor enhances the activity of natriuretic peptides, producing vasodilation, natriuresis, and diuresis. Angiotensin receptor blockers inhibit the renin-angiotensin-aldosterone system. Sacubitril/valsartan, a first-in-class angiotensin receptor-neprilysin inhibitor (ARNI), has been shown to improve cardiovascular outcomes in HFrEF and delay the progression of chronic kidney disease (CKD) in patients with HFrEF. The PARADIGM-HF study showed a reduction in diuretic need in the ARNI group. While the use of diuretics is effective in volume control in patients with HFrEF, their use has the potential to adversely affect renal function. Therefore, ARNI therapy could benefit patients with heart failure and CKD by reducing cardiovascular morbidity and mortality and possibly retarding the progression of CKD, although more clinical evidence is required in patients with severe CKD and end-stage renal disease.

Current evidence of sacubitril/valsartan in the treatment of heart failure with reduced ejection fraction

Heart failure (HF) is one of the most common reasons for hospital admission in western countries. The measurement of the left ventricular ejection fraction is essential for the classification of HF and deciding on HF treatment. The treatment of HF has been improved in both diagnostic and therapeutic fields over the past two decades. The angiotensin receptor-neprilysin inhibitor decreased the cardiovascular mortality in patients with chronic HF with reduced ejection fraction. Sacubitril/valsartan (LCZ696) improves the imbalance between the renin-angiotensin-aldosterone and natriuretic peptide systems. We present the clinical efficacy, real-world experience, safety and tolerability, the relevance of etiology of cardiomyopathy, and gender differences and regulatory affairs of LCZ696 in the treatment of patients with HF with reduced ejection fraction.

An evaluation of the fixed-dose combination sacubitril/valsartan for the treatment of arterial hypertension

INTRODUCTION

Essential hypertension is a significant risk factor for cardiovascular disease, renal disease, and mortality with increasing prevalence. Despite the availability of various antihypertensive agents, hypertension is still poorly controlled. Therefore, new chemical compounds with antihypertensive efficacy need to be developed. The dual angiotensin II receptor-neprilysin inhibitor LCZ696 is a single molecule synthesized by co-crystallization of valsartan and the neprilysin inhibitor prodrug sacubitril (1:1 molar ratio).

AREAS COVERED

This review includes an overview of hypertension and the current pharmacotherapy. The authors summarize the LCZ696 drug chemistry, pharmacodynamics, pharmacokinetics, metabolism, randomized control trials (RCTs), and safety concerns. Databases searched included PubMed, Google Scholar, Embase, and ClinicalTrials.gov.

EXPERT OPINION

LCZ696 is effective in hypertension treatment. Short-term RCTs have shown that the highest doses of LCZ696 (200 and 400 mg [q.d.]) were more effective at lowering office and ambulatory blood pressure than angiotensin II receptor blockers (ARB) alone while having a similar tolerability profile. The effects of LCZ696 on hypertensive organ damage are only sparsely investigated and so far no studies have established the impact of LCZ696 on cardiovascular event rates. Future studies should focus on the comparison of LCZ696 and combination therapies already in use such as ARB and calcium channel blockers.

Radiosynthesis of the 11 C-methyl derivative of LBQ657 for PET investigation of the neprilysin inhibitor sacubitril

Neprilysin, also known as neutral endopeptidase, is a cell surface membrane metalo-endopeptidase that cleaves various peptides. Altered neprilysin expression has been correlated with various cancers and cardiovascular diseases. In this work, we present the radiosynthesis of the novel O-11 C-methylated derivative of LBQ657 (a potent neprilysin inhibitor). (2R,4S)-5-(Biphenyl-4-yl)-4-[(3-carboxypropionyl)amino]-2-methylpentanoic acid [11 C]methyl ester ([11 C]MeOLBQ) is an analog of sacubitril where the alkyl ester is a 11 C-methyl instead of an ethyl. [11 C]MeOLBQ was produced in a one-pot two-step synthesis. The O-11 C-methylation of the pentanoic acid part was done with [11 C]methyl triflate followed by the deprotection of the tert-butyl ester precursor in acidic conditions. [11 C]MeOLBQ ([11 C]7) was produced in 9.5 ± 2.5% RCY (25 ± 6% decay-corrected from [11 C]CO2 , n = 3) high molar activity 348 ± 100 GBq/μmol (9425 ± 2720 mCi/μmol) at EOS, in high chemical (>95%) and radiochemical (>99%) purities. The total synthesis time including HPLC purification and reformulation was 29 minutes. To our knowledge, this is the first PET-labeled analog of the clinically used NEP inhibitor sacubitril.

Sacubitril/valsartan in patients with symptomatic chronic heart failure with reduced ejection fraction

Background:

Sacubitril/valsartan is a combination drug therapy for heart failure (HF) patients that has been shown to reduce mortality and hospitalisation.

Aims:

To explore clinically relevant real-life patient data regarding prescribing of sacubitril/valsartan for HF patients in three hospitals, in accordance with national guidelines.

Methods:

A retrospective multicentre study in three large UK hospital Trusts based in the West Midlands.

Findings:

A total of 118 symptomatic chronic HF patients with reduced ejection fraction were included in the study. A high proportion of prescribers adhered to NICE guidelines for treatment with sacubitril/valsartan; 99% of patients had a New York Heart Association functional class of at least II; 82% had a left ventricle ejection fraction of under 35%; 100% received an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker before commencing sacubitril/valsartan. The mean age of men and women at the three hospitals was 65 and 59 years, respectively. The proportion of men prescribed sacubitril/valsartan was greater than women: 80% compared to 20%, respectively. The majority of patients on the therapy were white British (65%). Total prescribing of sacubitril/valsartan at the three hospitals was 295 patients, lower than expected.

Conclusion:

The prescribing of sacubitril/valsartan at the Trusts generally adhered to NICE guidance; however, the prescribing rate was lower than expected compared with the NICE resource tool. Further investigations into the safety and scope of application of sacubitril/valsartan are required to match the prescribing of sacubitril/valsartan with eligible patients who could benefit from the medication.

Clinical Pharmacokinetics of Sacubitril/Valsartan (LCZ696): A Novel Angiotensin Receptor-Neprilysin Inhibitor

Sacubitril/valsartan (LCZ696) is indicated for the treatment of heart failure with reduced ejection fraction. Absorption of sacubitril/valsartan and conversion of sacubitril (prodrug) to sacubitrilat (neprilysin inhibitor) was rapid with maximum plasma concentrations of sacubitril, sacubitrilat, and valsartan (angiotensin receptor blocker) reaching within 0.5, 1.5-2.0, and 2.0-3.0 h, respectively. With a two-fold increase in dose, an increase in the area under the plasma concentration-time curve was proportional for sacubitril, ~1.9-fold for sacubitrilat, and ~1.7-fold for valsartan in healthy subjects. Following multiple twice-daily administration, steady-state maximum plasma concentration was reached within 3 days, showing no accumulation for sacubitril and valsartan, while ~1.6-fold accumulation for sacubitrilat. Sacubitril is eliminated predominantly as sacubitrilat through the kidney; valsartan is eliminated mainly by biliary route. Drug-drug interactions of sacubitril/valsartan were evaluated with medications commonly used in patients with heart failure including furosemide, warfarin, digoxin, carvedilol, levonorgestrel/ethinyl estradiol combination, amlodipine, omeprazole, hydrochlorothiazide, intravenous nitrates, metformin, statins, and sildenafil. Co-administration with sacubitril/valsartan increased the maximum plasma concentration (~2.0-fold) and area under the plasma concentration-time curve (1.3-fold) of atorvastatin; however, it did not affect the pharmacokinetics of simvastatin. Age, sex, or ethnicity did not affect the pharmacokinetics of sacubitril/valsartan. In patients with heart failure vs. healthy subjects, area under the plasma concentration-time curves of sacubitril, sacubitrilat, and valsartan were higher by approximately 1.6-, 2.1-, and 2.3-fold, respectively. Renal impairment had no significant impact on sacubitril and valsartan area under the plasma concentration-time curves, while the area under the plasma concentration-time curve of sacubitrilat correlated with degree of renal function (1.3-, 2.3-, 2.9-, and 3.3-fold with mild, moderate, and severe renal impairment, and end-stage renal disease, respectively). Moderate hepatic impairment increased the area under the plasma concentration-time curves of valsartan and sacubitrilat ~2.1-fold.

From ARB to ARNI in Cardiovascular Control

Coexistence of hypertension, diabetes mellitus and chronic kidney disease synergistically aggravates the risk of cardiovascular and renal morbidity and mortality. These high-risk, multi-morbid patient populations benefit less from currently available anti-hypertensive treatment. Simultaneous angiotensin II type 1 receptor blockade and neprilysin inhibition (‘ARNI’) with valsartan/sacubitril (LCZ696) might potentiate the beneficial effects of renin-angiotensin-aldosterone inhibition by reinforcing its endogenous counterbalance, the natriuretic peptide system. This review discusses effects obtained with this approach in animals and humans. In animal models of hypertension, either alone or in combination with myocardial infarction or diabetes, ARNI consistently reduced heart weight and cardiac fibrosis in a blood pressure-independent manner. Additionally, LCZ696 treatment reduced proteinuria, focal segmental glomerulosclerosis and retinopathy, thus simultaneously demonstrating favourable effects on microvascular complications. These results were confirmed in patient populations. Besides blood pressure reductions in hypertensive patients and greatly improved (cardiovascular) mortality in heart failure patients, ventricular wall stress and albuminuria were reduced particularly in diabetic patients. The exact underlying mechanism remains unknown, but may involve improved renal haemodynamics and reduced glomerulosclerosis, e.g. related to a rise in natriuretic peptide levels. However, the assays of these peptides are hampered by methodological artefacts. Moreover, since sacubitrilat is largely renally cleared, drug accumulation may occur in patients with impaired renal function and thus hypotension is a potential side effect in patients with chronic kidney disease. Further caution is warranted since neprilysin also degrades endothelin-1 and amyloid beta in animal models. Accumulation of the latter may increase the risk of Alzheimer’s disease.

Neprilysin inhibition and endothelin-1 elevation: Focus on the kidney

Increasing the degree of renin-angiotensin system (RAS) blockade by combining ≥2 RAS blockers marginally increases efficacy, but results in more side effects. Hence, interference with other systems is currently being investigated, like potentiation of natriuretic peptides with neprilysin inhibitors. However, the neprilysin inhibitor thiorphan was recently found to increase endothelin-1 when administered to TGR(mREN2)27 (Ren2) rats on top of RAS blockade. Here we investigated whether this effect is thiorphan-specific, by comparing the neprilysin inhibitors thiorphan and sacubitril, administered by osmotic minipumps at a low or high dose for 7 days, in Ren2 rats. Plasma and urinary levels of endothelin-1, atrial and brain natriuretic peptide (ANP, BNP) and their second messenger cyclic guanosine 3'5' monophosphate (cGMP) were monitored. No significant differences were found in the plasma concentrations of endothelin-1, cGMP, ANP and BNP after treatment, although plasma ANP tended to be higher in the high-dose thiorphan treatment group and the low- and high-dose sacubitril treatment groups, compared with vehicle. Urinary endothelin-1 increased in the low-dose thiorphan and high-dose sacubitril groups, compared with baseline, although significance was reached for the former only. Urinary cGMP rose significantly in the high-dose sacubitril treatment group compared with baseline. Both urinary endothelin-1 and cGMP were significantly higher in the high-dose sacubitril group compared with the low-dose sacubitril group. In conclusion, endothelin-1 upregulation occurs with both thiorphan and sacubitril, and is particularly apparent in neprilysin-rich organs like the kidney. High renal neprilysin levels most likely also explain why sacubitril increased cGMP in urine only.

Physiologically Based Pharmacokinetic Model Predictions of Panobinostat (LBH589) as a Victim and Perpetrator of Drug-Drug Interactions

Panobinostat (Farydak) is an orally active hydroxamic acid-derived histone deacetylase inhibitor used for the treatment of relapsed or refractory multiple myeloma. Based on recombinant cytochrome P450 (P450) kinetic analyses in vitro, panobinostat oxidative metabolism in human liver microsomes was mediated primarily by CYP3A4 with lower contributions by CYP2D6 and CYP2C19. Panobinostat was also an in vitro reversible and time-dependent inhibitor of CYP3A4/5 and a reversible inhibitor of CYP2D6 and CYP2C19. Based on a previous clinical drug-drug interaction study with ketoconazole (KTZ), the contribution of CYP3A4 in vivo was estimated to be ∼40%. Using clinical pharmacokinetic (PK) data from several trials, including the KTZ drug-drug interaction (DDI) study, a physiologically based pharmacokinetic (PBPK) model was built to predict panobinostat PK after single and multiple doses (within 2-fold of observed values for most trials) and the clinical DDI with KTZ (predicted and observed area under the curve ratios of 1.8). The model was then applied to predict the drug interaction with the strong CYP3A4 inducer rifampin (RIF) and the sensitive CYP3A4 substrate midazolam (MDZ) in lieu of clinical trials. Panobinostat exposure was predicted to decrease in the presence of RIF (65%) and inconsequentially increase MDZ exposure (4%). Additionally, PBPK modeling was used to examine the effects of stomach pH on the absorption of panobinostat in humans and determined that absorption of panobinostat is not expected to be affected by increases in stomach pH. The results from these studies were incorporated into the Food and Drug Administration-approved product label, providing guidance for panobinostat dosing recommendations when it is combined with other drugs.

Assessment of Drug-Drug Interaction Potential Between Atorvastatin and LCZ696, A Novel Angiotensin Receptor Neprilysin Inhibitor, in Healthy Chinese Male Subjects

BACKGROUND AND OBJECTIVE

LCZ696 (sacubitril/valsartan), a novel angiotensin receptor neprilysin inhibitor has been recently approved for the treatment of patients with heart failure (HF) and reduced ejection fraction. As several HF patients are likely to use statins as co-medications, the potential for a pharmacokinetic drug-drug interaction between atorvastatin and LCZ696 was evaluated.

METHODS

This was an open-label, three-period, single-sequence study in 28 healthy Chinese male subjects wherein LCZ696 200 mg was administered twice daily for 5 days in period 1. Following a washout period, atorvastatin 80 mg was administered once daily for 4 days (period 2) and subsequently co-administered with LCZ696 200 mg for 5 days (period 3). Serial plasma samples were collected to determine pharmacokinetic parameters of LCZ696 analytes (sacubitril, LBQ657, and valsartan) and atorvastatin and its metabolites.

RESULTS

Atorvastatin co-administration had no effect on the pharmacokinetics of LBQ657, while the AUC_τ,ss and C _max,ss of sacubitril increased by 30 and 19 %, respectively, and the corresponding values for valsartan decreased by 19 and 9 %, respectively. Co-administration with LCZ696 increased C _max,ss of atorvastatin, o-hydroxyatorvastatin, and p-hydroxyatorvastatin by 74, 68, and 108 %, respectively, and the AUC_τ,ss of corresponding analytes increased by 34, 22, and 26 %, respectively.

CONCLUSIONS

While atorvastatin had no significant impact on the pharmacokinetics of LCZ696 analytes upon co-administration, the C _max of atorvastatin and its metabolites increased twofold, with a marginal increase in AUC (<1.3-fold). Multiple-dose administration of LCZ696 200 mg twice daily and atorvastatin 80 mg once daily either alone or in combination was generally safe and well tolerated in healthy subjects.

Erratum to: Clinical Pharmacokinetics of Sacubitril/Valsartan (LCZ696): A Novel Angiotensin Receptor-Neprilysin Inhibitor

Sacubitril/valsartan (LCZ696) is indicated for the treatment of heart failure with reduced ejection fraction. Absorption of sacubitril/valsartan and conversion of sacubitril (prodrug) to sacubitrilat (neprilysin inhibitor) was rapid with maximum plasma concentrations of sacubitril, sacubitrilat, and valsartan (angiotensin receptor blocker) reaching within 0.5, 1.5-2.0, and 2.0-3.0 h, respectively. With a twofold increase in dose, an increase in the area under the plasma concentration-time curve was proportional for sacubitril, ~1.9-fold for sacubitrilat, and ~1.7-fold for valsartan in healthy subjects. Following multiple twice-daily administration, steady-state maximum plasma concentration was reached within 3 days, showing no accumulation for sacubitril and valsartan, while ~1.6-fold accumulation for sacubitrilat. Sacubitril is eliminated predominantly as sacubitrilat through the kidney; valsartan is eliminated mainly by biliary route. Drug-drug interactions of sacubitril/valsartan were evaluated with medications commonly used in patients with heart failure including furosemide, warfarin, digoxin, carvedilol, levonorgestrel/ethinyl estradiol combination, amlodipine, omeprazole, hydrochlorothiazide, intravenous nitrates, metformin, statins, and sildenafil. Co-administration with sacubitril/valsartan increased the maximum plasma concentration (~2.0-fold) and area under the plasma concentration-time curve (1.3-fold) of atorvastatin; however, it did not affect the pharmacokinetics of simvastatin. Age, sex, or ethnicity did not affect the pharmacokinetics of sacubitril/valsartan. In patients with heart failure vs. healthy subjects, area under the plasma concentration-time curves of sacubitril, sacubitrilat, and valsartan were higher by approximately 1.6-, 2.1-, and 2.3-fold, respectively. Renal impairment had no significant impact on sacubitril and valsartan area under the plasma concentration-time curves, while the area under the plasma concentration-time curve of sacubitrilat correlated with degree of renal function (1.3-, 2.3-, 2.9-, and 3.3-fold with mild, moderate, and severe renal impairment, and end-stage renal disease, respectively). Moderate hepatic impairment increased the area under the plasma concentration-time curves of valsartan and sacubitrilat ~2.1-fold.

Potential beneficial effects of sacubitril-valsartan in renal disease: a new field for a new drug

Patients with renal dysfunction are at a higher risk of cardiovascular disease (CVD), which often shares manifestations with heart failure (HF). Last year, the FDA approved the use of sacubitril-valsartan in patients with HF. This dual-acting agent enhances the functions of natriuretic peptides and inhibits the renin-angiotensin system. Areas covered: This review summarizes the existing preclinical and clinical studies carried out with sacubitril-valsartan (and other drugs with similar pharmacological mechanisms) in HF and hypertensive patients. We put the focus on the renal data provided by these studies. Data were obtained from English peer-reviewed articles on PubMed and clinical trials registered in ClinicalTrials.gov. Expert opinion: Overall, sacubitril-valsartan might be a promising therapeutic approach in patients with renal dysfunction. Renal conditions with marked CV risk, such as arterionephrosclerosis, could constitute a particular setting where to evaluate the impact of the drug. Nevertheless, large, randomized trials are needed to confirm the beneficial effects and safety profile of the drug in renal patients, as well as to elucidate some concerns observed in HF trials, such as the slight increase in proteinuria.

Transport properties of valsartan, sacubitril and its active metabolite (LBQ657) as determinants of disposition

1. The potential for drug-drug interactions of LCZ696 (a novel, crystalline complex comprising sacubitril and valsartan) was investigated in vitro. 2. Sacubitril was shown to be a highly permeable P-glycoprotein (P-gp) substrate and was hydrolyzed to the active anionic metabolite LBQ657 by human carboxylesterase 1 (CES1b and 1c). The multidrug resistance-associated protein 2 (MRP2) was shown to be capable of LBQ657 and valsartan transport that contributes to the elimination of either compound. 3. LBQ657 and valsartan were transported by OAT1, OAT3, OATP1B1 and OATP1B3, whereas no OAT- or OATP-mediated sacubitril transport was observed. 4. The contribution of OATP1B3 to valsartan transport (73%) was appreciably higher than that by OATP1B1 (27%), Alternatively, OATP1B1 contribution to the hepatic uptake of LBQ657 (∼70%) was higher than that by OATP1B3 (∼30%). 5. None of the compounds inhibited OCT1/OCT2, MATE1/MATE2-K, P-gp, or BCRP. Sacubitril and LBQ657 inhibited OAT3 but not OAT1, and valsartan inhibited the activity of both OAT1 and OAT3. Sacubitril and valsartan inhibited OATP1B1 and OATP1B3, whereas LBQ657 weakly inhibited OATP1B1 but not OATP1B3. 6. Drug interactions due to the inhibition of transporters are unlikely due to the redundancy of the available transport pathways (LBQ657: OATP1B1/OAT1/3 and valsartan: OATP1B3/OAT1/3) and the low therapeutic concentration of the LCZ696 analytes.

Angiotensin receptor neprilysin inhibitor LCZ696: pharmacology, pharmacokinetics and clinical development

Heart failure still has a significant disease burden with poor outcomes worldwide despite advances in therapy. The standard therapies have been focused on blockade of renin–angiotensin–aldosterone system with angiotensin-converting enzyme inhibitors, angiotensin receptor blockers and mineralocorticoid antagonists and the sympathetic nervous system with β-blockers. The natriuretic peptide system is a potential counter-regulatory system that promotes vasodilatation and natriuresis. Angiotensin receptor neprilysin inhibitors are a new class drug capable of blocking the renin–angiotensin–aldosterone system and enhancing the natriuretic peptide system to improve neurohormonal balance. The success of the PARADIGM-HF trial with LCZ696 and its approval for heart failure treatment is likely to generate a paradigm shift. This review summarises the current knowledge of LCZ696 with a focus on pharmacology, pharmacokinetics and pharmacodynamics, mechanisms of action, clinical efficacy and safety.

Evaluation of Drug-Drug Interaction Potential Between Sacubitril/Valsartan (LCZ696) and Statins Using a Physiologically Based Pharmacokinetic Model

Sacubitril/valsartan (LCZ696) has been approved for the treatment of heart failure. Sacubitril is an in vitro inhibitor of organic anion-transporting polypeptides (OATPs). In clinical studies, LCZ696 increased atorvastatin C_max by 1.7-fold and area under the plasma concentration-time curve by 1.3-fold, but had little or no effect on simvastatin or simvastatin acid exposure. A physiologically based pharmacokinetics modeling approach was applied to explore the underlying mechanisms behind the statin-specific LCZ696 drug interaction observations. The model incorporated OATP-mediated clearance (CL_int,T) for simvastatin and simvastatin acid to successfully describe the pharmacokinetic profiles of either analyte in the absence or presence of LCZ696. Moreover, the model successfully described the clinically observed drug effect with atorvastatin. The simulations clarified the critical parameters responsible for the observation of a low, yet clinically relevant, drug-drug interaction DDI between sacubitril and atorvastatin and the lack of effect with simvastatin acid. Atorvastatin is administered in its active form and rapidly achieves C_max that coincide with the low C_max of sacubitril. In contrast, simvastatin requires a hydrolysis step to the acid form and therefore is not present at the site of interactions at sacubitril concentrations that are inhibitory. Similar models were used to evaluate the drug-drug interaction risk for additional OATP-transported statins which predicted to maximally result in a 1.5-fold exposure increase.

Sacubitril/Valsartan (LCZ696) in Heart Failure

It has been known since the 1990s that long-term morbidity and mortality is improved in patients with heart failure with reduced ejection fraction (HFrEF) by treatments that target the renin-angiotensin-aldosterone system (RAAS). It has also long been thought that enhancement of the activity of natriuretic peptides (NPs) could potentially benefit patients with HFrEF, but multiple attempts to realize this benefit had failed over the years - until 2014, when a large, phase III, randomized, controlled clinical trial (PARADIGM-HF) was completed comparing sacubitril/valsartan with enalapril, a well-established treatment for HFrEF. Sacubitril/valsartan (formerly known as LCZ696) is a first-in-class angiotensin receptor neprilysin inhibitor (ARNI) that simultaneously suppresses RAAS activation through blockade of angiotensin II type 1 receptors and enhances vasoactive peptides including NPs through inhibition of neprilysin, the enzyme responsible for their degradation. In PARADIGM-HF, patients with HFrEF treated with sacubitril/valsartan had 20% less risk for cardiovascular death or hospitalization for heart failure (the primary endpoint), 20% less risk for cardiovascular death, 21% less risk for first hospitalization for heart failure, and 16% less risk for death from any cause, compared with enalapril (all p < 0.001). Concerning tolerability, the sacubitril/valsartan group had higher proportions of patients with hypotension and nonserious angioedema but lower proportions with renal impairment, hyperkalemia, and cough, compared with the enalapril group. The use of sacubitril/valsartan has been endorsed by the latest heart failure treatment guidelines in Europe and the USA. This chapter reviews the discoveries, scientific reasoning, and clinical evidence that led to the development of sacubitril/valsartan, the first novel therapy in a new drug class to improve survival in HFrEF in the last 15 years.

In vitro and clinical evaluation of OATP-mediated drug interaction potential of sacubitril/valsartan (LCZ696)

WHAT IS KNOWN AND OBJECTIVE

Sacubitril/valsartan (LCZ696) has been recently approved for the treatment of heart failure (HF) patients with reduced ejection fraction. Several HF patients receive statins as co-medication.

METHODS

Because clearance of statins is meditated via OATP1B1/1B3, the inhibition potential of these transporters by LCZ696 analytes was evaluated in vitro. Furthermore, an open-label, fixed-sequence clinical study was conducted to determine the effect of LCZ696 on the exposure of simvastatin and its active metabolite simvastatin acid. In this clinical study, 26 healthy subjects received simvastatin 40 mg alone or in combination with LCZ696 or after 1 or 2 h of LCZ696 dosing.

RESULTS AND DISCUSSION

Although no significant inhibition by LBQ657 (an active metabolite of sacubitril) and valsartan was observed, sacubitril inhibited OATP1B1 and OATP1B3 in vitro, with IC50 of 1·91 and 3·81 μm, respectively. Upon co-administration of simvastatin with LCZ696, the Cmax of simvastatin and simvastatin acid decreased by 7% and 13%, respectively. When administered 1 h after LCZ696 dosing, the corresponding Cmax of simvastatin and simvastatin acid decreased by 16% and 4%, respectively. When administered 2 h after LCZ696 dosing, the Cmax of simvastatin decreased by 33% and that of simvastatin acid increased by 16%. However, no notable changes were observed in the AUCs of simvastatin or simvastatin acid upon co-administration or time-separated administration with LCZ696. No notable impact of simvastatin co-administration was observed on the pharmacokinetics of LCZ696 analytes. LCZ696 and simvastatin were generally well tolerated when administered alone or in combination.

WHAT IS NEW AND CONCLUSIONS

Overall, the results of this study suggest that although sacubitril inhibited OATP1B1 and OATP1B3 in vitro, it does not translate into any clinically relevant in vivo effect.