Plecanatide Improves Abdominal Bloating and Bowel Symptoms of Irritable Bowel Syndrome with Constipation.

BACKGROUND: Bloating is a bothersome symptom in irritable bowel syndrome with constipation (IBS-C). AIM: To evaluate plecanatide efficacy in patients with IBS-C stratified by bloating intensity. METHODS: Pooled phase 3 data (2 randomized, controlled IBS-C trials) from adults treated with plecanatide 3 mg or placebo for 12 weeks were analyzed. Patients were stratified post-hoc by baseline bloating severity (11-point scale: mild [≤ 5] and moderate-to-severe [> 5]). Assessments included change from baseline in bloating, abdominal pain, and complete spontaneous bowel movement (CSBM) frequency. Abdominal pain and bloating composite responders were defined as patients with ≥ 30% improvement from baseline in both bloating and abdominal pain at Week 12. RESULTS: At baseline, 1104/1436 patients with IBS-C (76.9%) reported moderate-to-severe bloating. In the moderate-to-severe bloating subgroup, plecanatide significantly reduced bloating severity versus placebo (least-squares mean change [LSMC]: - 1.7 vs - 1.3; P = 0.002), reduced abdominal pain (- 1.7 vs - 1.3; P = 0.006), and increased CSBM frequency (1.4 vs 0.8; P < 0.0001). In the mild bloating subgroup, significant improvements were observed with plecanatide versus placebo for abdominal pain (LSMC: - 1.3 vs - 1.0; P = 0.046) and CSBM frequency (2.0 vs 1.2; P = 0.003) but not bloating (- 0.9 vs - 0.8; P = 0.28). A significantly greater percentage of patients were abdominal pain and bloating composite responders with plecanatide versus placebo (moderate-to-severe bloating: 33.6% vs 26.8% [P = 0.02]; mild bloating: 38.4% vs 27.2% [P = 0.03]). CONCLUSION: Plecanatide treatment improved IBS-C abdominal and bowel symptoms, including in those who present with moderate-to-severe bloating.

Effect of sacubitril/valsartan on natriuretic peptide in patients with compensated heart failure.

The time-dependent changes in the natriuretic peptide families during sacubitril/valsartan (S/V) treatment remain obscure in the Asian heart failure (HF) cohort. Eighty-one outpatients with compensated HF were analyzed. The patients were divided into two groups based on the administration of S/V (n = 42) or angiotensin converting enzyme inhibitor (ACE-I; n = 39). Changes to the natriuretic peptide families and the daily dose of loop diuretics were evaluated 3 and 6 months after the intervention. The atrial natriuretic peptide (ANP) level was significantly increased (102 [63-160] pg/mL to 283 [171-614] pg/mL [3 months]; 409 [210-726] pg/mL [6 months]) in the S/V group but not in the ACE-I group. The dose of furosemide was significantly decreased during the six-month follow-up period in the S/V group (40 [20-40] mg to 20 [10-20] mg) but not in the ACE-I group. A multivariate logistic regression model showed that the presence of persistent atrial fibrillation (AF) and HF with a preserved left ventricular ejection fraction (HFpEF) was independently associated with a high delta-ANP ratio (≥ 4.5 ANP value on the start date/ANP value at 6 months; the mean value was used as the cutoff value) (odds ratio [OR]: 4.649, 95% CI 1.032-20.952 and OR: 7.558, 95% CI 1.427-40.042). The plasma level of ANP was increased, and the loop diuretic dose was decreased by the addition of neprilysin inhibitor therapy in patients with compensated HF. In patients with HFpEF and complicated persistent AF, neprilysin inhibitor therapy was associated with an increase in ANP.

Protection of kidney function and tissue integrity by pharmacologic use of natriuretic peptides and neprilysin inhibitors.

With variable potencies atrial-, brain-type and c-type natriuretic peptides (NP)s, best documented for ANP and its analogues, promote sodium and water excretion, renal blood flow, lipolysis, lower blood pressure, and suppress renin and aldosterone secretion through interaction predominantly with cGMP-coupled NPR-A receptor. Infusion of especially ANP and its analogues up to 50 ng/kg/min in patients with high risk of acute kidney injury (cardiac vascular bypass surgery, intraabdominal surgery, direct kidney surgery) protects kidney function (GFR, plasma flow, medullary flow, albuminuria, renal replacement therapy, tissue injury) at short term and also long term and likely additively with the diuretic furosemide. This documents a pharmacologic potential for the pathway. Neprilysin (NEP, neutral endopeptidase) degrades NPs, in particular ANP, and angiotensin II. The drug LCZ696, a mixture of the neprilysin inhibitor sacubitril and the ANGII-AT1 receptor blocker valsartan, was FDA approved in 2015 and marketed as Entresto®. In preclinical studies of kidney injury, LCZ696 and NPs lowered plasma creatinine, countered hypoxia and oxidative stress, suppressed proinflammatory cytokines, and inhibited fibrosis. Few randomized clinical studies exist and were designed with primary cardiac outcomes. The studies showed that LCZ696/entresto stabilized and improved glomerular filtration rate in patients with chronic kidney disease. LCZ696 is safe to use concerning kidney function and stabilizes or increases GFR. In perspective, combined AT1 and neprilysin inhibition is a promising approach for long-term renal protection in addition to AT1 receptor blockers in acute kidney injury and chronic kidney disease.

CRRL269.

RATIONALE: Acute kidney injury (AKI) has a high prevalence and mortality in critically ill patients. It is also a powerful risk factor for heart failure incidence driven by hemodynamic changes and neurohormonal activation. However, no drugs have been approved by the Food and Drug Administration. Endogenous pGC-A (particulate guanylyl cyclase A receptor) activators were reported to preserve renal function and improve mortality in AKI patients, although hypotension accompanied by pGC-A activators have limited their therapeutic potential. OBJECTIVE: We investigated the therapeutic potential of a nonhypotensive pGC-A activator/designer natriuretic peptide, CRRL269, in a short-term, large animal model of ischemia-induced AKI and also investigated the potential of uCNP (urinary C-type natriuretic peptide) as a biomarker for AKI. METHODS AND RESULTS: We first showed that CRRL269 stimulated cGMP generation, suppressed plasma angiotensin II, and reduced cardiac filling pressures without lowering blood pressure in the AKI canine model. We also demonstrated that CRRL269 preserved glomerular filtration rate, increased renal blood flow, and promoted diuresis and natriuresis. Further, CRRL269 reduced kidney injury and apoptosis as evidenced by ex vivo histology and tissue apoptosis analysis. We also showed, compared with native pGC-A activators, that CRRL269 is a more potent inhibitor of apoptosis in renal cells and induced less decreases in intracellular Ca2+ concentration in vascular smooth muscle cells. The renal antiapoptotic effects were at least mediated by cGMP/PKG pathway. Further, CRRL269 inhibited proapoptotic genes expression using a polymerase chain reaction gene array. Additionally, we demonstrated that AKI increased uCNP levels. CONCLUSIONS: Our study supports developing CRRL269 as a novel renocardiac protective agent for AKI treatment.

Venom natriuretic peptides guide the design of heart failure therapeutics.

Heart failure (HF) affects over 26 million people world-wide. It is a syndrome triggered by loss of normal cardiac function due to many acute (eg myocardial infarction) and/or chronic (eg hypertension) causes and characterized by mixed beneficial and deleterious activation of a complex of multifaceted neurohormonal systems the net effect of which frequently is further adverse disruption of pressure-volume homeostasis. Unlike the situation in chronic heart failure, current strategies for treatment of acute heart failure are empirical and lack a strong evidence base. Management includes any of a combination of vasodilators, diuretics and ionotropic agents depending on the hemodynamic profile of the patient. Despite the improvement in the options available to improve outcomes in patients with chronic HF, for several decades little gain has been made in the treatment of the acute decompensated state. Morbidity and mortality rates remain high necessitating new therapeutic agents. The cardiac natriuretic peptides (NPs) are key hormones in pressure-volume homoeostasis. There are three isoforms of mammalian NPs, namely ANP, BNP and CNP. These peptides bind to membrane-bound NP receptors (NPRs) on the heart, vasculature and kidney to lower blood pressure and circulating volume. Intravenous infusion of NPs in HF patients improves hemodynamic status but is associated with occasional severe hypotension. Apart from mammalian NPs, snake venom NPs are an excellent source of pharmacologically distinct ligands that offer the possibility of engineering NPs for therapeutic purposes. Venom NPs have long half-lives, differential NPR activation profiles and varied NPR specificity. The scaffolds of venom NPs encode the molecular information for designing NPs with longer half-lives and improved and differential vascular and renal functions. This review focuses on the structure-function paradigm of mammalian and venom NPs and the different peptide engineering strategies that have been utilized in the design of clinically relevant new NP-analogues.

Efficacy of Secretagogues in Patients With Irritable Bowel Syndrome With Constipation: Systematic Review and Network Meta-analysis.

BACKGROUND & AIMS: Several secretagogues have been approved for the treatment of irritable bowel syndrome with constipation (IBS-C). However, their relative efficacy is unclear because there have been no head-to-head randomized controlled trials. We conducted a network meta-analysis to compare their efficacies in patients with IBS-C. METHODS: We searched MEDLINE, EMBASE, EMBASE Classic, and the Cochrane Central Register of Controlled Trials through June 2018 to identify randomized controlled trials assessing the efficacy of secretagogues in adults with IBS-C. Trials included in the analysis reported a dichotomous assessment of overall response to therapy, and data were pooled using a random-effects model. Efficacy and safety of secretagogues were reported as a pooled relative risk with 95% confidence interval to summarize the effect of each comparison tested, and treatments were ranked according to their P score. RESULTS: We identified 15 eligible randomized controlled trials of secretagogues that included 8462 patients. Linaclotide, lubiprostone, plecanatide, and tenapanor were superior to placebo for the treatment of IBS-C. Linaclotide (290 µg once daily) was ranked first in efficacy based on the end point recommended by the Food and Drug Administration for trials in IBS-C, the primary end point used in each trial, abdominal pain, and complete spontaneous bowel movements. Tenapanor (50 mg twice daily) was ranked first for decreasing bloating. Total numbers of adverse events were significantly larger with linaclotide (290 and 500 µg once daily) and plecanatide (3 mg once daily) compared with placebo. However, plecanatide 6 mg once daily ranked first for safety. Diarrhea was significantly more common with all drugs, except lubiprostone (8 µg twice daily). Nausea was significantly more common in patients who received lubiprostone. CONCLUSIONS: In a network analysis of randomized controlled trials of secretagogues for IBS-C, we found all drugs to be superior to placebo. Efficacy was similar among individual drugs and dosages for most end points. However, data were extracted at the 12-week time point, so the long-term relative efficacy of these drugs is unknown.

New Pharmacological Strategies to Increase cGMP.

The intracellular nucleotide cyclic guanosine monophosphate (cGMP) is found in many human organ tissues. Its concentration increases in response to the activation of receptor enzymes called guanylyl cyclases (GCs). Different ligands bind GCs, generating the second messenger cGMP, which in turn leads to a variety of biological actions. A deficit or dysfunction of this pathway at the cardiac, vascular, and renal levels manifests in cardiovascular diseases such as heart failure, arterial hypertension, and pulmonary arterial hypertension. An impairment of the cGMP pathway also may be involved in the pathogenesis of obesity as well as dementia. Therefore, agents enhancing the generation of cGMP for the treatment of these conditions have been intensively studied. Some have already been approved, and others are currently under investigation. This review discusses the potential of novel drugs directly or indirectly targeting cGMP as well as the progress of research to date.

Efficacy and Tolerability of Guanylate Cyclase-C Agonists for Irritable Bowel Syndrome with Constipation and Chronic Idiopathic Constipation: A Systematic Review and Meta-Analysis.

OBJECTIVES: Linaclotide and plecanatide are guanylate cyclase-C (GCC) agonists for the treatment of chronic idiopathic constipation (CIC) and irritable bowel syndrome with constipation (IBS-C). Our objective is to evaluate the efficacy and tolerability of GCC agonists based on data from multiple randomized controlled trials (RCTs). METHODS: We searched PubMED, EMBASE, Cochrane databases, clinicaltrials.gov, major conference abstracts, Food and Drug Administration (FDA) websites, and United States Securities and Exchange Commission filings of drug sponsors to identify RCTs of CIC or IBS-C patients. We assessed efficacy based on FDA-approved composite responder endpoints, diarrhea as an adverse event, and study withdrawal owing to diarrhea for each therapy. Trial results were pooled using DerSimonian and Laird random effects model of meta-analysis and exact logistic regression when appropriate with 95% confidence intervals. Meta-regression was performed to compare outcomes between therapies adjusting for placebo event rate. RESULTS: Eight linaclotide trials (five CIC; three IBS-C) and seven plecanatide trials (four CIC; three IBS-C) evaluating 10,369 patients met inclusion criteria. FDA publications documented that different definitions for diarrhea were used in linaclotide vs. plecanatide trials. Both drugs were efficacious in treating CIC (linaclotide 72 µg (Odds ratio (OR)=3.11, 95% CI 1.81-5.34); linaclotide 145 µg (OR=3.25, 2.15-4.91); plecanatide 3 mg (OR=1.99, 1.57-2.51)) and IBS-C (linaclotide 290 µg (OR=2.43, 1.48-3.98); plecanatide 3 mg (OR=1.87, 1.47-2.38); plecanatide 6 mg (OR=1.92, 1.48-2.48)). Diarrhea occurred in excess of placebo in treating CIC (linaclotide 72 µg (OR=3.07, 1.97-4.77); linaclotide 145 µg (OR=3.70, 2.69-5.10); plecanatide 3 mg (OR=3.86, 1.83-8.12)) and IBS-C (linaclotide 290 µg (OR=8.02, 5.20-12.37); plecanatide 3 mg (OR=5.55, 1.62-19.00); plecanatide 6 mg (OR=4.13, 1.57-10.83)). Based on meta-regression, there were no statistically significant differences between therapies in odds ratios for efficacy, diarrhea, or diarrhea-related study withdrawals. CONCLUSIONS: Both linaclotide and plecanatide demonstrate similar efficacy and tolerability in treating IBS-C and CIC. No differences in odds of diarrhea were seen between linaclotide and plecanatide.

2018 New Drug Update.

Five new drugs marketed within the last year, which are used for medical problems often experienced by the elderly, have been selected for consideration in this review. The uses and most important properties of these agents are discussed, and a rating for each new drug is determined using the New Drug Comparison Rating system developed by the author (DAH). Advantages, disadvantages, and other important information regarding each new drug are identified and used as the basis for determining the rating. The drugs include an anticoagulant, an antiparkinson agent, an agent for tardive dyskinesia, an agent for psoriasis, and an agent for constipation. The drugs reviewed are betrixaban, safinamide mesylate, valbenazine tosylate, guselkumab, and plecanatide.

A Randomized Phase III Clinical Trial of Plecanatide, a Uroguanylin Analog, in Patients With Chronic Idiopathic Constipation.

OBJECTIVES: This study assessed the efficacy and safety of plecanatide, a guanylate cyclase-C (GC-C) agonist and the first uroguanylin analog approved for the treatment of chronic idiopathic constipation (CIC). METHODS: This phase III, multicenter, double-blind, placebo-controlled study randomized 1,394 patients with CIC. Patients received either plecanatide (3 or 6 mg) or placebo, orally, once daily, for 12 weeks. The primary efficacy endpoint was the percentage of patients who were durable overall complete spontaneous bowel movement (CSBM) responders over the 12-week treatment period. Patients were instructed to record their daily bowel movements, stool consistency scores, and abdominal symptoms in an electronic diary. Treatment-emergent adverse events (AEs) were collected. RESULTS: Each dose of plecanatide resulted in a significantly greater percentage of durable overall CSBM responders (21.0%, 3 mg; 19.5%, 6 mg) as compared with placebo (10.2%; P<0.001 for both). Plecanatide (3 and 6 mg) also significantly increased mean weekly CSBM frequency from baseline (increase of 2.5 and 2.2/week, respectively) vs. placebo (1.2/week; P<0.001 for both) and mean weekly spontaneous bowel movement frequency (increase of 3.2 and 3.1/week, respectively) vs. placebo (1.3/week; P<0.001, for both) over the 12-week treatment period. Both plecanatide doses significantly improved all secondary and additional efficacy endpoints. The most common AE, diarrhea, occurred in 1.3% (placebo), 5.9% (3 mg) and 5.7% (6 mg) of patients. CONCLUSIONS: Plecanatide significantly improved constipation and its related symptoms with a low rate of adverse events. These results suggest that plecanatide will be a useful treatment option in the management of CIC. ClinicalTrials.gov: NCT01982240.

Natriuretic Peptides: The Case of Prostate Cancer.

Cardiac natriuretic peptides have long been known to act as main players in the homeostatic control of blood pressure, salt and water balance. However, in the last few decades, new properties have been ascribed to these hormones. A systematic review of English articles using MEDLINE Search terms included prostate cancer, inflammation, cardiac hormones, atrial natriuretic peptide, and brain natriuretic peptide. Most recent publications were selected. Natriuretic peptides are strongly connected to the immune system, whose two branches, innate and adaptive, are finely tuned and organized to kill invaders and repair injured tissues. These peptides control the immune response and act as anti-inflammatory and immune-modulatory agents. In addition, in cancers, natriuretic peptides have anti-proliferative effects by molecular mechanisms based on the inhibition/regulation of several pathways promoting cell proliferation and survival. Nowadays, it is accepted that chronic inflammation is a crucial player in prostate cancer development and progression. In this review, we summarize the current knowledge on the link between prostate cancer and inflammation and the potential use of natriuretic peptides as anti-inflammatory and anticancer agents.

$850 Per Bowel Movement?! Hard To Justify That Cost.

Constipation can be a serious and painful problem, and we shouldn't dismiss other people's suffering. On the other hand there's a danger when new medications are compared against placebo rather than against over-the-counter products with a history of effectiveness.

Role of Angiotensin Receptor-Neprilysin Inhibition in Heart Failure.

PURPOSE OF REVIEW: Numerous evidence-based medical and device therapies proven to reduce morbidity and mortality have advanced care for heart failure with reduced ejection fraction (HFrEF). The primacy of this approach has now been superseded by striking new data resulting in the approval of the combination of valsartan and sacubitril, a neprilysin inhibitor (also known as LCZ696), in 2015 for the treatment of HFrEF. LCZ696 is a novel heart failure drug that simultaneously inhibits the renin-angiotensin system and potentiates the natriuretic peptide system. RECENT FINDINGS: In the Prospective Comparison of ARNI with ACE-I to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial, LCZ696 significantly improved cardiovascular outcomes compared to current guideline-directed medical therapy. Compared to an angiotensin-converting enzyme (ACE) inhibitor, LCZ696 was associated with a 20 % reduction in cardiovascular mortality (number needed to treat [NNT] 32) and a similar reduction in total mortality (NNT 36). Morbidity benefits of the drug were seen within 1 month of initiation. However, hypotension due to enalapril or the LCZ696 regimen during a run-in phase eliminated 20 % of patients. Safety concerns included the risk of angioedema and the theoretical concern of neurocognitive dysfunction due to the protean effects of neprilysin inhibition. The role of LCZ696 in patients with asymptomatic left ventricular systolic dysfunction is uncertain. LCZ696 is currently being evaluated in patients with heart failure with preserved ejection fraction, with promising initial results. LCZ696 represents a novel mechanistic approach to targeting heart failure with reduced ejection fraction, and ongoing studies will address its use in other cardiovascular populations.

Natriuretic Peptides as a Novel Target in Resistant Hypertension.

Resistant hypertension is defined as blood pressure not under goal despite being on at least three antihypertensives. Resistant hypertension is associated with significant cardiovascular morbidity and mortality. Currently, the mainstay for the treatment of resistant hypertension is lifestyle modification and antihypertensive drugs. Natriuretic peptides play an important role in regulating cardiovascular hemodynamics and sodium and fluid homeostasis including blood pressure control. They hold a promising potential for treatment of resistant hypertension.

Rationale and therapeutic opportunities for natriuretic peptide system augmentation in heart failure.

The natriuretic peptide system (NPS) is intimately involved in cardiorenal homeostasis in health, and dysregulation of the NPS plays an important role in the pathophysiology of heart failure (HF). Indeed, the diuretic, vasorelaxation, beneficial remodeling, and potent neurohumoral inhibition of the NPS support the therapeutic development of chronic augmentation of the NPS in symptomatic HF. Further, chronic augmentation of the protective NPS and in early stages of HF may ultimately prevent the progression of HF and reduced subsequent morbidity and mortality. In the current manuscript, we review the rationale for as well as previous and current efforts aimed at chronic therapeutic augmentation of the NPS in HF.

Natriuretic peptides in cardiovascular diseases: current use and perspectives.

The natriuretic peptides (NPs) family, including atrial, B-type, and C-type NPs, is a group of hormones possessing relevant haemodynamic and anti-remodelling actions in the cardiovascular (CV) system. Due to their diuretic, natriuretic, vasorelaxant, anti-proliferative, and anti-hypertrophic effects, they are involved in the pathogenic mechanisms leading to major CV diseases, such as heart failure (HF), coronary artery disease, hypertension and left ventricular hypertrophy, and cerebrovascular accidents. Blood levels of NPs have established predictive value in the diagnosis of HF, as well as for its prognostic stratification. In addition, they provide useful clinical information in hypertension and in both stable and unstable coronary artery disease. Structural abnormalities of atrial natriuretic peptide gene (NPPA), as well as genetically induced changes in circulating levels of NPs, have a pathogenic causal link with CV diseases and represent emerging markers of CV risk. Novel NP-based therapeutic strategies are currently under advanced clinical development, as they are expected to contribute to the future management of hypertension and HF. The present review provides a current appraisal of NPs' clinical implications and a critical perspective of the potential therapeutic impact of pharmacological manipulation of this class of CV hormones.

Neutral endopeptidase inhibition and the natriuretic peptide system: an evolving strategy in cardiovascular therapeutics.

Hypertension and heart failure (HF) are common diseases that, despite advances in medical therapy, continue to be associated with high morbidity and mortality. Therefore, innovative therapeutic strategies are needed. Inhibition of the neutral endopeptidase (NEPinh) had been investigated as a potential novel therapeutic approach because of its ability to increase the plasma concentrations of the natriuretic peptides (NPs). Indeed, the NPs have potent natriuretic and vasodilator properties, inhibit the activity of the renin-angiotensin-aldosterone system, lower sympathetic drive, and have antiproliferative and antihypertrophic effects. Such potentially beneficial effects can be theoretically achieved by the use of NEPinh. However, studies have shown that NEPinh alone does not result in clinically meaningful blood pressure-lowering actions. More recently, NEPinh has been used in combination with other cardiovascular agents, such as angiotensin-converting enzyme inhibitors, and antagonists of the angiotensin receptor. Another future possible combination would be the use of NEPinh with NPs or their newly developed chimeric peptides. This review summarizes the current knowledge of the use and effects of NEPinh alone or in combination with other therapeutic agents for the treatment of human cardiovascular disease such as HF and hypertension.

Beyond Natriuretic Peptides: Unveiling the Power of Emerging Biomarkers in Heart Failure.

Heart failure (HF) represents a significant global health challenge, characterized by high morbidity and mortality rates, and imposes considerable burdens on healthcare systems and patient quality of life. Traditional management strategies, primarily relying on clinical assessments and standard biomarkers like natriuretic peptides, face limitations due to the heterogeneity of HF. This review aims to delve into the evolving landscape of non-natriuretic biomarkers and the transformative potential of omics technologies, underscoring their roles in advancing HF treatment towards precision medicine. By offering novel insights into the biological underpinnings of HF, including inflammation, myocardial stress, fibrosis, and metabolic disturbances, these advancements facilitate more accurate patient phenotyping and individualized treatment strategies. The integration of non-natriuretic biomarkers and omics technologies heralds a pivotal shift in HF management, enabling a move towards tailored therapeutic interventions. This approach promises to enhance clinical outcomes by improving diagnostic accuracy, risk stratification, and monitoring therapeutic responses. However, challenges such as the variability in biomarker levels, cost-effectiveness, and the standardization of biomarker testing across different healthcare settings pose hurdles to their widespread adoption. Despite these challenges, the promise of precision medicine in HF, driven by these innovative biomarkers and technologies, offers a new horizon for improving patient care and outcomes. This review advocates for the further integration of these advancements into clinical practice, highlighting the need for ongoing research to fully realize their potential in transforming the landscape of heart failure management.