The Catechol O-Methyltransferase Inhibitor Entacapone in the Treatment of Parkinson's Disease: Personal Reflections on a First-in-Class Drug Development Programme 40 Years On.

In the 1980s, Orion Pharma, then a mid-ranking Nordic area pharmaceutical company, established a drug development programme on the inhibition of catechol O-methyltransferase (COMT). This enzyme, which plays an important role in the inactivation of catecholamine neurotransmitters and drugs with a catechol structure, thus came under consideration as a target in the innovative translational and clinical programme we describe in this historical review. The starting point was the conjecture that a peripherally acting COMT inhibitor might improve entry of levodopa into the brain. This had potentially significant implications for the medical treatment of Parkinson's disease (PD). The rationale was that more efficient delivery of levodopa to the brain might allow the high therapeutic doses of levodopa to be reduced and the dose interval to be extended. Elucidation of structure-activity relations paved the way for the discovery and development of entacapone, a 5-nitrocatechol that was a potent and highly specific inhibitor of COMT. Experience in phase III clinical trials established that entacapone, used as an adjunct to regular or controlled-release levodopa preparations (also including a peripherally acting dopa-decarboxylase inhibitor), increased ON-time and reduced OFF-time and improved clinical condition in patients with PD experiencing wearing-off, often with a reduced daily levodopa dose. Several of these studies also identified that entacapone improved patients' quality of life and was cost-effective. Subsequently, entacapone has been amalgamated into a triple-combination preparation (Stalevo®) with levodopa and carbidopa to create a flexible and convenient drug therapy for patients with PD who have end-of-dose motor fluctuations not stabilised on levodopa/dopa-decarboxylase inhibitor treatment. This review offers a historical perspective on a successful programme of drug development by researchers who played central roles in the progress from exploratory hypothesis to registered pharmaceutical product.

A roadmap for therapeutic discovery in pulmonary hypertension associated with left heart failure. A scientific statement of the Heart Failure Association (HFA) of the ESC and the ESC Working Group on Pulmonary Circulation & Right Ventricular Function.

Pulmonary hypertension (PH) associated with left heart failure (LHF) (PH-LHF) is one of the most common causes of PH. It directly contributes to symptoms and reduced functional capacity and negatively affects right heart function, ultimately leading to a poor prognosis. There are no specific treatments for PH-LHF, despite the high number of drugs tested so far. This scientific document addresses the main knowledge gaps in PH-LHF with emphasis on pathophysiology and clinical trials. Key identified issues include better understanding of the role of pulmonary venous versus arteriolar remodelling, multidimensional phenotyping to recognize patient subgroups positioned to respond to different therapies, and conduct of rigorous pre-clinical studies combining small and large animal models. Advancements in these areas are expected to better inform the design of clinical trials and extend treatment options beyond those effective in pulmonary arterial hypertension. Enrichment strategies, endpoint assessments, and thorough haemodynamic studies, both at rest and during exercise, are proposed to play primary roles to optimize early-stage development of candidate therapies for PH-LHF.

Repeated Levosimendan Infusions in the Management of Advanced Heart Failure: Review of the Evidence and Meta-analysis of the Effect on Mortality.

ABSTRACT: In the latest years, several studies described the impact of repetitive/intermittent i.v. levosimendan treatment in the management of advanced heart failure. For this updated review, we systematically searched the literature for clinical trials, registries , and real-world data and identified 31 studies that we commented in a narrative review: 3814 patients were described, of whom 1744 were treated repetitively with levosimendan. On the basis of the nature of the study protocols and of the end points, out of those studies, we further selected 9 that had characteristics, making them suitable for a meta-analysis on mortality. This short list describes data from 680 patients (of whom 399 received repeated doses of levosimendan) and 110 death events (of which 50 occurred in the levosimendan cohort). In the meta-analysis, repetitive/intermittent therapy with i.v. levosimendan was associated with a significant reduction in mortality at the longest time point available: 50 of 399 (12.5%) versus 60 of 281 (21.4%) in the control arms, with a risk ratio of 0.62 (95% confidence interval, 0.42-0.90; P < 0.01). In a sensitivity analysis, removing each trial and reanalyzing the remaining data set did not change the trend, magnitude, or significance of the results. A visual inspection of the funnel plot did not suggest publication bias. The results provide a very strong rationale for continuing to investigate the repetitive use of levosimendan in patients with advanced heart failure by properly powered regulatory clinical trials. Meanwhile, it seems that the use of repetitive/intermittent i.v. levosimendan infusions has become one of the few effective options for preserving the hemodynamic and symptomatic balance in such patients.

Use of Levosimendan in Patients with Pulmonary Hypertension: What is the Current Evidence?

Pulmonary hypertension, defined as an increase in mean arterial pressure > 20 mmHg, is a chronic and progressive condition with high mortality and morbidity. Drug therapy of patients with pulmonary hypertension is based on the distinctive pathophysiologic aspect that characterizes the different groups. However, recently, levosimendan, a calcium-sensitizing agent with inotropic, pulmonary vasodilator, and cardioprotective properties, has been shown to be an effective and safe therapeutic strategy for patients with pulmonary arterial hypertension (in addition to specific drugs) and pulmonary hypertension associated with left heart disease (as possible treatment). This review provides a comprehensive overview of the current evidence on the use of levosimendan in patients with pulmonary hypertension.

Use of Levosimendan in Patients with Advanced Heart Failure: An Update.

Levosimendan is an inodilator drug that, given its unique pharmacological actions and safety profile, represents a viable therapeutic option in patients with heart failure with reduced ejection fraction in the advanced stage of the disease (advHFrEF). Pulsed levosimendan infusion in patients with advHFrEF improves symptoms and clinical and hemodynamic status, prevents recurrent hospitalizations, and enables optimization of guidelines-directed medical therapy. Furthermore, considering its proprieties on right ventricular function and pulmonary circulation, levosimendan could be helpful for the prevention and treatment of the right ventricular dysfunction post-implanting a left ventricular assist device. However, to date, evidence on this issue is scarce and has yielded mixed results. Finally, preliminary experiences indicate that treatment with levosimendan at scheduled intervals may serve as a "bridge to transplant" strategy in patients with advHFrEF. In this review, we summarized the clinical pharmacology of levosimendan, the available evidence in the treatment of patients with advHFrEF, as well as a hypothesis for its use in patients with advanced heart failure with preserved ejection fraction.

Levosimendan as a "Bridge to Optimization" in Patients with Advanced Heart Failure with Reduced Ejection-A Single-Center Study.

Background: Patients with advanced heart failure with reduced ejection fraction often cannot tolerate target doses of guideline-directed medical therapy due to symptomatic hypotension, renal dysfunction, and associated electrolyte abnormalities. While levosimendan can facilitate the titration of ß-blockers in patients with advanced HFrEF, it is unclear whether ambulatory levosimendan infusions would offer the same benefit. In this prospective study, we investigate the effects of intermittent ambulatory levosimendan infusions on the uptitration of disease-modifying drugs. Methods: We enrolled 37 patients with advanced HFrEF who received repeated ambulatory infusions of levosimendan between January 2018 and January 2021. The demographic, clinical, and laboratory data were acquired 24 h before the first and the last ambulatory levosimendan infusion. Results: At the 1 year follow-up, the enrolled patients were on significantly higher doses of guideline-directed medical therapy, including bisoprolol (3.2 ± 2.8 mg vs. 5.9 ± 4.1 mg; p = 0.02), sacubitril/valsartan (41.67 ± 32.48 mg vs. 68.5 ± 35.72 mg; p = 0.01), and eplerenone (12.7 ± 8.5 mg vs. 22.8 ± 13.6 mg; p = 0.03). Furthermore, a substantial decrease in the furosemide dose was observed (123.2 ± 32.48 mg vs. 81.6 ± 19.47 mg; p < 0.0001). Conclusions: Levosimendan facilitates the optimization of disease-modifying heart failure medications in previously intolerant advanced HFrEF patients.

The Adenylate Cyclase Activator Forskolin Potentiates the Positive Inotropic Effect of the Phosphodiesterase Inhibitor Milrinone But Not of the Calcium Sensitizer Levosimendan nor of Its Hemodynamically Active Metabolites: An Apparent Conundrum.

ABSTRACT: OR-1855 and OR-1896 are 2 hemodynamically active metabolites of the inodilator levosimendan, with calcium sensitizing activity, but their mechanism of action is still not fully understood. It has been previously reported that the positive inotropic effect of levosimendan is not potentiated by the adenylate cyclase activator forskolin, whereas forskolin does potentiate the effects of the phosphodiesterase (PDE) inhibitor milrinone. To ascertain whether the active metabolites follow the same pattern of levosimendan, the positive inotropic effects of OR- 1855 and OR-1896 were studied in guinea-pig-isolated papillary muscle in the presence and absence of forskolin. OR-1855 and OR-1896 were also tested as inhibitors of PDE-III and PDE-IV. Our results show that 0.1 µM forskolin did not potentiate the positive inotropic effect of OR-1855 or OR-1896, as in the case of the parent compound levosimendan. As in previous studies, the positive inotropic effect of milrinone was markedly potentiated in the presence of forskolin. From these data, we propose an explanation for the divergent behavior of the calcium sensitizing drugs and PDE inhibitors.

Hemodynamic Effects of Levosimendan in Outpatients With Advanced Heart Failure: An Echocardiographic Pilot Study.

ABSTRACT: Infusions of levosimendan delivered in ambulatory/outpatient settings have been shown to improve quality of life and reduce hospitalizations in patients with advanced heart failure (HF). The aim of this pilot study was to evaluate the effects of ambulatory infusion of levosimendan on echocardiographic markers of perfusion, congestion, and cardiovascular efficiency. Thirty patients with diagnosed advanced HF underwent ambulatorial infusion of levosimendan at a total dose of 6.25 mg as a part of a repetitive biweekly treatment strategy with the inotrope. Standardized transthoracic echocardiography and Doppler examinations, were performed 1 hour before and 48 hours after completion of ambulatory infusion. At 48 hours after ambulatory infusion of levosimendan, a significant increase in the stroke volume (37.47 ± 12.38 mL/beat vs. 45.47 ± 14.48 mL/beat; P < 0.05) and cardiac output (2.64 ± 0.66 L/min vs. 3.26 ± 0.57 L/min; P < 0.05) occurred. Significant postreductions versus prereductions were also recorded in left atrial pressure (27.37 ± 6.62 mm Hg vs. 22.82 ± 4.17 mm Hg; P < 0.01), mean pulmonary artery pressure (27.69 ± 4.64 mm Hg vs. 23.24 ± 5.32; P < 0.01), and inferior vena cava diameter (23.81 ± 7.63 mm vs. 18.53 ± 4.82 mm; P < 0.01). Significant improvements were noted in the resting cardiac power output (0.46 ± 0.15 watt vs. 0.53 ± 0.22 watt; P < 0.01) and the resting cardiac power index (0.24 ± 0.08 watt/m2 vs. 0.28 ± 0.11 watt/m2; P < 0.01). In outpatients with advanced HF, infusion of levosimendan was associated with hemodynamic responses that may contribute to the clinical benefit previously reported in such patients.

Levosimendan in Europe and China: An Appraisal of Evidence and Context.

The calcium sensitiser levosimendan (SIMDAX; Orion Pharma) has been in clinical use for the management of acute heart failure and a range of related syndromes in many countries around the world for two decades. More recently, levosimendan has become available in China. The authors have examined the profile of levosimendan in clinical trials conducted inside and outside China and grouped the findings under six headings: effects on haemodynamics, effects on natriuretic peptides, effect on symptoms of heart failure, renal effects, effect on survival, and safety profile. Their conclusions are that under each of these headings there are reasonable grounds to expect that the effects and clinical benefits established in trials and with wider clinical use in Europe and elsewhere will accrue also to Chinese patients. Therefore, the authors are confident that global experience with levosimendan provides a reliable guide to its optimal use and likely therapeutic effects in patients in China.

Levosimendan-induced venodilation is mediated by opening of potassium channels.

Unique vascular responses adhere to the cardiovascular efficacy of the inodilator levosimendan. In particular, selective venodilation appears to explain its clinical benefit during pulmonary hypertension complicated by heart failure with preserved ejection fraction. Vasodilators increase vessel diameter in various parts of the vascular system to different degrees and thereby influence blood pressure, its distribution, and organ perfusion depending on their mechanisms of action. Levosimendan and its long-lived active metabolite OR-1896 mobilize a set of vasodilatory mechanisms, that is, the opening of the ATP-sensitive K+ channels and other K+ channels on top of a highly selective inhibition of the phosphodiesterase III enzyme. A vessel-specific combination of the above vasodilator mechanisms-in concert with cardiac effects and cardiovascular reflex regulations-illustrates the pharmacological profile of levosimendan in various cardiovascular disorders. While levosimendan has been known to be an inotrope, its properties as an activator of ATP-sensitive K+ channels have gone largely ignored with respect to clinical applications. Here, we provide a summary of what is known about the ATP-sensitive K+ channel properties in preclinical studies and now for the first time, its ATP-sensitive K+ channel properties in a clinical trial.

An update on levosimendan in acute cardiac care: applications and recommendations for optimal efficacy and safety.

Introduction: In the 20 years since its introduction to the palette of intravenous hemodynamic therapies, the inodilator levosimendan has established itself as a valuable asset for the management of acute decompensated heart failure. Its pharmacology is notable for delivering inotropy via calcium sensitization without an increase in myocardial oxygen consumption.Areas covered: Experience with levosimendan has led to its applications expanding into perioperative hemodynamic support and various critical care settings, as well as an array of situations associated with acutely decompensated heart failure, such as right ventricular failure, cardiogenic shock with multi-organ dysfunction, and cardio-renal syndrome. Evidence suggests that levosimendan may be preferable to milrinone for patients in cardiogenic shock after cardiac surgery or for weaning from extracorporeal life support and may be superior to dobutamine in terms of short-term survival, especially in patients on beta-blockers. Positive effects on kidney function have been noted, further differentiating levosimendan from catecholamines and phosphodiesterase inhibitors.Expert opinion:Levosimendan can be a valuable resource in the treatment of acute cardiac dysfunction, especially in the presence of beta-blockers or ischemic cardiomyopathy. When attention is given to avoiding or correcting hypovolemia and hypokalemia, an early use of the drug in the treatment algorithm is preferred.

Short-term treatments for acute cardiac care: inotropes and inodilators.

Acute heart failure (AHF) continues to be a substantial cause of illness and death, with in-hospital and 3-month mortality rates of 5% and 10%, respectively, and 6-month re-admission rates in excess of 50% in a range of clinical trials and registry studies; the European Society of Cardiology (ESC) Heart Failure Long-Term Registry recorded a 1-year death or rehospitalization rate of 36%. As regards the short-term treatment of AHF patients, evidence was collected in the ESC Heart Failure Long-Term Registry that intravenous (i.v.) treatments are administered heterogeneously in the critical phase, with limited reference to guideline recommendations. Moreover, recent decades have been characterized by a prolonged lack of successful innovation in this field, with a plethora of clinical trials generating neutral or inconclusive findings on long-term mortality effects from a multiplicity of short-term interventions in AHF. One of the few exceptions has been the calcium sensitizer and inodilator levosimendan, introduced 20 years ago for the treatment of acutely decompensated chronic heart failure. In the present review, we will focus on the utility of this agent in the wider context of i.v. inotropic and inodilating therapies for AHF and related pathologies.

Differential effects of inotropes and inodilators on renal function in acute cardiac care.

Pathological interplay between the heart and kidneys is widely encountered in heart failure (HF) and is linked to worse prognosis and quality of life. Inotropes, along with diuretics and vasodilators, are a core medical response to HF but decompensated patients who need inotropic support often present with an acute worsening of renal function. The impact of inotropes on renal function is thus potentially an important influence on the choice of therapy. There is currently relatively little objective data available to guide the selection of inotrope therapy but recent direct observations on the effects of levosimendan and milrinone on glomerular filtration favour levosimendan. Other lines of evidence indicate that in acute decompensated HF levosimendan has an immediate renoprotective effect by increasing renal blood flow through preferential vasodilation of the renal afferent arterioles and increases in glomerular filtration rate: potential for renal medullary ischaemia is avoided by an offsetting increase in renal oxygen delivery. These indications of a putative reno-protective action of levosimendan support the view that this calcium-sensitizing inodilator may be preferable to dobutamine or other adrenergic inotropes in some settings by virtue of its renal effects. Additional large studies will be required, however, to clarify the renal effects of levosimendan in this and other relevant clinical situations, such as cardiac surgery.

Levosimendan Improves Oxidative Balance in Cardiogenic Shock/Low Cardiac Output Patients.

The beneficial effects exerted by levosimendan against cardiac failure could be related to the modulation of oxidative balance. We aimed to examine the effects of levosimendan in patients with cardiogenic shock or low cardiac output on cardiac systo-diastolic function and plasma oxidants/antioxidants (glutathione, GSH; thiobarbituric acid reactive substances, TBARS). In four patients undergoing coronary artery bypass grafting or angioplasty, cardiovascular parameters and plasma GSH and TBARS were measured at T0 (before levosimendan infusion), T1 (1 h after the achievement of the therapeutic dosage of levosimendan), T2 (end of levosimendan infusion), T3 (72 h after the end of levosimendan infusion), and T4 (end of cardiogenic shock). We found an improvement in the indices of systolic (ejection fraction, cardiac output, cardiac index) and diastolic (E to early diastolic mitral annular tissue velocity, E/'; early to late diastolic transmitral flow velocity, EA) cardiac function at early T2. A reduction of central venous pressure and pulmonary wedge pressure was also observed. Plasma levels of GSH and TBARS were restored by levosimendan at T1, as well. The results obtained indicate that levosimendan administration can regulate oxidant/antioxidant balance as an early effect in cardiogenic shock/low cardiac output patients. Modulation of oxidative status on a mitochondrial level could thus play a role in exerting the cardio-protection exerted by levosimendan in these patients.