Recent Patents on Cardiovascular Drug Discovery (Discontinued) - Volume 6, Issue 1, 2011

Vernakalant is a novel anti-arrhythmic drug, recently approved for the cardioversion of recent-onset atrial fibrillation. Its action is mainly due to the blockade of atrial-selective channels responsible of the ultra-rapid delayed rectifier current IKur, but has also important interactions with other channels and currents, such as INa (inward sodium current), and IKACh (acetylcholine-regulated potassium current). Due to the relatively selective blockade of the IKur, vernakalant prolongs the effective refractory period of the atria with minimal effects on the ventricles, thus minimizing the risk of proarrhythmia. Thus far vernakalant has been tested in three placebo-controlled trials (ACT I, ACT II and ACT III) and in one amiodarone-controlled study (AVRO). Vernakalant has been demonstrated more effective than both placebo and amiodarone for the rapid conversion of atrial fibrillation, without significant adverse events. This article will review the recent patents on this novel atrial-selective agent, discussing its mechanisms of action and possible clinical applications in the real-world practice.

Levosimendan is one of the documented pharmacological agents used in the management and treatment of acute and chronic heart failure; it is a novel inodilator agent which enhanced myocardial performance without changes in oxygen consumption. The combination of positive inotropic and vasodilator effects of levosimendan relates to its Ca2+- sensitizing and K+ channels opening effects. Levosimendan has been proposed, in the recent past, to be non-inferior and may have some advantages to standard inotropes; further possible indications for levosimendan have been described, in some observational studies, such as a perioperative use, cardioprotection, cardiogenic shock, sepsis and right ventricular dysfunction. The ability of levosimendan to improve myocardial function without substantially increasing oxygen consumption may appear paradoxical but is possible via improved efficacy not only with regard to the effects on the contractile apparatus of the cardiomyocytes. The aim of this review is to describe the pharmacological characteristics of levosimendan and its clinical applications. The patent review data regarding the use of Levosimendan are also discussed in this review article.

Atherosclerosis and its clinical sequelae still represent the primary cause of death in Western societies. During the past 25 years, a novel drug class to treat dyslipidemia, a main risk factor for coronary artery disease, emerged: liver- and thyroid hormone receptor isoform β- selective analogs. The present review will discuss the recent patents applied for sobetirome (GC-1), which set the course for the establishment of a novel approach to lower plasma cholesterol and triglycerides. We will focus on the major mechanisms conferring sobetirome lipid-lowering properties, including the induction of hepatic LDL receptor, the promotion of the so-called reverse cholesterol transport, and finally the induction of bile acid production and biliary sterol secretion. In summary, thyromimetics such as sobetirome may represent a useful treatment for combined hyperlipidemia, which is associated with a major cardiovascular risk.

Levosimendan is a calcium sensitizer with positive inotropic and vasodilating properties. It increases the sensitivity of troponin C for calcium, opens adenosine triphosphate-dependent potassium (K+) channels and inhibits phosphodiesterase III. Levosimendan is approved for use in cardiac failure but large clinical trials have raised doubts whether levosimendan is superior to β-adrenergic agonists regarding long-term survival of patients. Despite this controversy, there is growing evidence of beneficial effects of levosimendan in ischemia/reperfusion (I/R) injury due to its effect on K+ channels. As a consequence, patents on K+ channel agonists have been granted recently for reducing injury in organs or tissue in transplants and trauma therapy. Moreover, experimental studies and clinical trials have shown that levosimendan effectively inhibits cardiomyocyte apoptosis. The underlying molecular mechanism is currently unclear. However, it is tempting to assume that levosimendan inhibits cardiomyocyte apoptosis due to its beneficial effect on I/R injury. However, the link between these two phenomena has not been well established. This review summarizes experimental studies and clinical trials on the effects of levosimendan in I/R injury and apoptosis also discussing recent patents.

Ultrasound imaging is widely used worldwide principally because it is cheap, easily available and contains no exposure to ionizing radiation. The advent of microbubble ultrasound contrast has further increased the diagnostic sensitivity and specificity of this technique thus widening its clinical applications. The third generation of ultrasound contrast agents consist of sulphur hexafluoride microbubbles encased in a phospholipid shell. This review will elaborate on the pharmacology, safety profile and method of action of these agents. We also aim to discuss the ever expanding uses for contrast enhanced ultrasound in a number of clinical specialities which include the liver, kidney, prostate, sentinel node detection, vascular tree and endovascular stent surveillance. We will also discuss some of the recent patents regarding the future uses of ultrasound microbubble contrast and recent technological advances in clinical applications.

Matrix metalloproteinases (MMPs) have a pivotal role in the natural history of atherosclerosis and its cardiovascular consequences. Non-selective MMP inhibition with doxycycline appears as a potential strategy to reduce the residual risk observed in patients already at intensive lipid lowering strategies. However, specific MMPs have different and even contradicting roles in the natural history of atherosclerosis, rendering broad spectrum MMP inhibition an important yet somewhat simplistic approach towards residual risk reduction in coronary atherosclerosis. Overall, the balance of non-selective MMP inhibition might shift to the favorable side in particular settings such as in acute coronary syndromes, where in addition to its potential plaque stabilization properties, doxycycline shows promise in preventing ischemia-reperfusion injury and left ventricular remodeling. Nevertheless, to date, most animal models used do not represent advanced coronary atherosclerosis seen in humans, and large and well-designed clinical studies are lacking. We discuss the available evidence and recent patents supporting the role of doxycycline in atherosclerosis.

Recent advances in technology and novel pharmaceutical research findings have added new grounds in the fields of medical treatment and quality of life of patients diagnosed with pulmonary arterial hypertension (PAH). Collective assessment of new data is mandatory and useful for specialist medical doctors. This review aims to present the latest therapeutic developments of the last two years (2009-2010) in PAH. Moreover, recent patents (of the year 2010) regarding therapeutic novelties in PAH that expand treatment modalities, are hereby presented.

A great number of observations show that cardiovascular damage from smoking may be a consequence of both active and passive smoking exposure. Some findings identify an increase in cardiovascular events in active smokers as well as in non-smokers exposed to passive smoking. The type and extension of damage seem to be similar qualitatively either in active smokers or in exposed never smokers. Artery vessels and myocardium feel particularly the effects of smoking. Ischaemic heart disease and atherosclerosis progression are the common alterations observed. Individuals exposed to both active and passive smoking feel the adverse effects of smoking. Result of the interaction consists primarily of increased rate of clinical events whereas the type of anatomical alterations is similar to those which characterize respectively isolated exposure to active or passive smoking. However, the extension of cardiovascular damage may vary even if, usually, in the same location of pre-existing lesions. The article also presents some of the patents regarding the effects of smoking on cardiovascular system.

The patents annotated in this section have been selected from various patent databases. These recent patents are relevant to the articles published in this journal issue, categorized by therapeutic areas/targets and therapeutic agents related to cardiovascular drug discovery.