Combination therapy for obesity and metabolic disease

Evaluate the Effects of Different Types of Preoperative Restricted Calorie Diets on Weight, Body Mass Index, Operation Time and Hospital Stay in Patients Undergoing Bariatric Surgery: a Systematic Review and Meta Analysis Study

Previous studies investigated low-calorie diets (LCD), very-low-calorie diets (VLCD), and very-low-calorie ketogenic diets (VLCKD) in relation to weight loss and outcomes for bariatric surgery patients. However, the overall effects of these diets on various outcomes remain unclear. This study aimed to assess the impact of preoperative restricted calorie diets on weight, body mass index (BMI), operation time (OT), and hospital stay (HS) in bariatric surgery patients. Seventeen articles were analyzed, revealing the highest weight loss (-8.62) and BMI reduction (-5.75) with VLCKD. Due to insufficient data, the impact of these diets on OT and HS could not be determined. Further interventional studies are required to determine the ideal preoperative diet that achieves optimal weight loss, patient compliance, tolerance, acceptance, and surgical outcomes.

Hypothesis: Amelioration of obesity-induced cognitive dysfunction via a lorcaserin-betahistine combination treatment

The prolonged exposure to obesogenic diets disrupts the mesocortical dopaminergic input to the prefrontal cortex (PFC). This leads to suboptimal dopamine levels in this brain region, which affects cognition and control of food intake. Treatments that restore mesocortical dopaminergic neurotransmission may improve obesity‐associated cognitive dysfunction and modulate food intake to induce weight loss. Given the complexity and multifactorial nature of obesity, combination treatments would likely achieve sizeable and sustained body weight loss and improve obesity‐linked outcomes, such as cognitive dysfunction. Given this background, we hypothesize that concomitant activation of serotonin 5‐HT2C and histamine H1 receptors, coupled with antagonism of histamine H3 receptors, synergistically modulates mesocortical dopamine neurotransmission and ameliorates obesity‐induced cognitive dysfunction. We propose to test the hypothesis in a diet‐induced obesity (DIO) rat model by treating animals with the 5‐HT2C agonist lorcaserin and the H1 agonist and H3 antagonist betahistine. Consistent with our hypothesis, both lorcaserin and betahistine have been shown to reduce body weight in humans with obesity and animals. Both drugs have been demonstrated to improve cognitive functions by influencing dopaminergic signaling in the PFC. The proposed combination treatment addresses the paucity of studies on obesity treatments that improve cognitive function. This research may also help identify a potential targetable mechanism connecting obesity and neurocognitive outcomes.

The limits and challenges of antiobesity pharmacotherapy

INTRODUCTION

Pharmacotherapy is a useful adjunct when patients with obesity are unable to achieve adequate benefit from lifestyle interventions.

AREAS COVERED

This review covers the history of antiobesity drugs, efficacy, and risks of currently approved drugs, limits of their usefulness in clinical practice, gaps in knowledge, methodological limitations of clinical trials, and reasons for underutilization.

EXPERT OPINION

In randomized controlled trials, currently approved antiobesity drugs have yielded an average weight loss ranging from approximately 3% to 9% relative to placebo at 1 year. Inadequate inclusion of racial and ethnic minorities and men, and high dropout rates in clinical trials limit generalizability of these findings to clinical practice. Weight loss achieved with antiobesity drugs is generally associated with lowered glycemia, but improvements in blood pressure and lipid measures tend to be marginal. There is limited evidence for sustained weight loss beyond 1 year and for safety and efficacy of antiobesity drugs in children and adolescents, and in post-bariatric surgery patients. None have demonstrated reduction in major adverse cardiovascular events or other significant disease outcomes. Limited health insurance coverage and negative perceptions of physicians have hindered the utilization of antiobesity drugs.

Obesity: Pathophysiology and Management

Obesity continues to be among the top health concerns across the globe. Despite our failure to contain the high prevalence of obesity, we now have a better understanding of its pathophysiology, and how excess adiposity leads to type 2 diabetes, hypertension, and cardiovascular disease. Lifestyle modification is recommended as the cornerstone of obesity management, but many patients do not achieve long-lasting benefits due to difficulty with adherence as well as physiological and neurohormonal adaptation of the body in response to weight loss. Fortunately, 5 drug therapies-orlistat, lorcaserin, liraglutide, phentermine/topiramate, and naltrexone/bupropion-are available for long-term weight management. Additionally, several medical devices are available for short-term and long-term use. Bariatric surgery yields substantial and sustained weight loss with resolution of type 2 diabetes, although due to the high cost and a small risk of serious complications, it is generally recommended for patients with severe obesity. Benefit-to-risk balance should guide treatment decisions.

Drug treatment of obesity: current status and future prospects

Obesity is a growing epidemic and a major contributor to the global burden of disease. Obesity strains the healthcare systems and has profound economic and psychosocial consequences. Historically, pharmacotherapy for obesity has witnessed the rise and fall of several promising drug candidates that had to be eventually withdrawn due to unacceptable safety concerns. Currently four drugs are approved for chronic weight management in obese adults: orlistat, lorcaserin, phentermine/topiramate extended release and naltrexone/bupropion extended release. While lorcaserin and phentermine/topiramate were approved by US Food and Drug Administration (FDA) in 2012, after a gap of 13 years following the licensing of orlistat, naltrexone/bupropion has been recently approved in 2014. This review provides a brief overview of these current therapeutic interventions available for management of obesity along with the evidence of their safety and efficacy. Additionally, several novel monotherapies as well as combination products are undergoing evaluation in various stages of clinical development. These therapies if proven successful will strengthen the existing armamentarium of antiobesity drugs and will be critical to combat the global public health crisis of obesity and its associated co-morbidities.

One-year human experience with a novel endoluminal, endoscopic gastric bypass sleeve for morbid obesity

INTRODUCTION

Here, we report the first series of patients with 1-year implantation of a novel, endoluminal, endoscopically delivered and retrieved gastro-duodeno-jejunal bypass sleeve (GJBS) (ValenTx, Inc. Carpinteria, CA, USA). In this report, we present the safety, feasibility of the device, weight loss, and changes in comorbidities.

METHODS AND PROCEDURES

A prospective, single-center, 12-month trial was designed. The patients are morbidly obese individuals who meet the NIH criteria for bariatric surgery. The GJBS is a 120-cm sleeve secured at the esophago-gastric junction with endoscopic and laparoscopic techniques that is designed to create an endoluminal gastro-duodeno-jejunal bypass. The device was implanted and, at the completion of the trial, retrieved with an endoscopic technique. The primary endpoints were safety and incidence of adverse events. The secondary outcomes included the percentage of excess weight loss (EWL) and changes in comorbidities, specifically glucose control, use of antihyperglycemics, and changes in hemoglobin A1C levels.

RESULTS

From July 2009 until October 2009, 13 patients were prospectively enrolled for the 1-year trial. The study included five men and eight women with a mean preoperative BMI of 42 kg/m(2). One patient was excluded, at the time of endoscopic evaluation, due to inflammation at the GE junction. Two additional patients required early explantation of the device, within the first 4 weeks, due to patient intolerance. Upon explant of the device, both patients' symptoms improved. In the remaining ten patients, the device was implanted, left in situ for 12 months, and then retrieved endoscopically. Safe delivery of the cuff at the gastro-esophageal junction was seen in all ten patients whom had device implants, without complication. No esophageal leak was seen immediately post-procedure or during follow-up. The sleeve device was well tolerated within the bowel lumen during the 12-month study, specifically, no bowel erosions, ulceration, or pancreatitis was observed. All ten patients reached the 1-year mark. Of the ten, six had fully attached and functional devices throughout the follow-up, verified by endoscopy. The mean percentage EWL, at 1 year, in this group was 54 %. In the remaining four patients, partial cuff detachment was observed at follow-up endoscopy. The percentage EWL was lower in this group. Of the six patients that reached a year with a fully attached device, five were followed at an average of 14-months post-explant (26 months from the time of device implant). These five maintained an average percentage EWL of 30 % at the 14-month post-explant follow-up. Co-morbidites measured included diabetes mellitus, hypertension, hyperlipidemia, and use of antihyperglycemics. Each of the measured comorbidities showed improvement during the 12-month trial.

DISCUSSION

The endoluminal, GJBS can be safely placed and retrieved. The short-term data show it is well tolerated with a good safety profile. It achieves excellent weight loss results with over 70 % of all comorbidities resolved or significantly improved.

Combination phentermine/topiramate for obesity treatment in primary care: a review

The treatment of obesity is often met with a myriad of challenges in the primary care setting. Nevertheless, a modest 5% weight loss is considered clinically significant and may be associated with health benefits. Phentermine/topiramate (Qsymia), available in the United States since September 2012, achieves clinically meaningful weight loss along with improvements in weight-related comorbidities. This combination drug therapy could be an additional tool for primary care providers in their quest for effective management of obesity. Special precautions and close monitoring are indicated when prescribing phentermine/topiramate for women of childbearing potential. Monitoring of heart rate and psychiatric and cognitive side effects is important.

Current pharmacotherapy for obesity: extrapolation of clinical trials data to practice

INTRODUCTION

When used prudently and in combination with lifestyle modification, pharmacotherapy has an important role in the management of obesity.

AREAS COVERED

This review covers targets for antiobesity drugs, challenges and limitations, failed translation of basic science to clinical practice, methodological and regulatory issues in clinical trials of pharmacotherapy, efficacy and risks of drugs currently approved for obesity, and clinical practice issues when using antiobesity drugs with emphasis on recently approved drugs.

EXPERT OPINION

Drugs currently approved for long-term therapy of obesity offer modest benefits for most patients, substantial benefits for some and no benefits for others. Numerous methodological problems including exclusion of the type of patients who are most often seen in clinical practices, inadequate enrollment of men and minorities, exclusion of patients taking antidepressants, high dropout rates, lack of follow-up after treatment discontinuation, and less than ideal imputation methods in data analysis limit the interpretation of clinical trials data and generalizability. Single-drug therapies offer small to moderate weight-loss benefits, but are generally better tolerated. Efficacy is enhanced with combination drug therapies, but so are the hazards. Clinicians should base their decisions on the expected and observed benefit-to-risk balance.

Individual empowerment in overweight and obese patients: a study protocol

INTRODUCTION

Obesity is a growing health problem in Europe and it causes many diseases. Many weight-reducing methods are reported in medical literature, but none of them proved to be effective in maintaining the results achieved over time. Self-empowerment can be an important innovative method, but an effectiveness study is necessary. In order to standardise the procedures for a randomised controlled study, a pilot study will be run to observe, measure and evaluate the effects of a period of self-empowerment group treatment on overweight/obese patients.

METHODS

and analysis Non-controlled, experimental, pilot study. A selected group of patients with body mass index >25, with no severe psychiatric disorders, with no aesthetic or therapeutic motivation will be included in the study. A set of quantitative and qualitative measures will be utilised to evaluate the effects of a self-empowerment course in a 12 month time. Group therapy and medical examinations will also complete this observational phase. At the end of this pilot study, a set of appropriate measures and procedures to determine the effectiveness of individual empowerment will be identified and agreed among the different professional figures. Results will be recorded and analysed to start a randomised controlled trial to evaluate the effectiveness of the proposed methodology.

ETHICS AND DISSEMINATION

This protocol was approved by the local Ethics Committee of Udine in March 2012. The findings of the trial will be disseminated through peer-reviewed journals, national and international conference presentations and public events involving the local administrations of the towns where the trial participants are resident.

TRIAL REGISTRATION

http://www.clinicalstrials.gov identifier NCT01644708.

Clinical utility of phentermine/topiramate (Qsymia™) combination for the treatment of obesity

Qsymia™ (Vivus Inc, Mountain View, CA, USA), a combination of phentermine and delayed-release topiramate, has been available in the US since September 2012 for the treatment of obesity. Phentermine is an anorexigenic agent, which is approved for the short-term treatment of obesity, while topiramate is approved for nonweight loss indications - seizure disorders and migraine prophylaxis. The amount of weight loss achieved with combination therapy is of a greater magnitude than what could be achieved with either agent alone. Adverse events that occur with the combination therapy are in line with the known side effect profiles of the constituent drugs; teratogenicity, a slight increase in heart rate, psychiatric and cognitive adverse effects, and metabolic acidosis are concerns.

Animal models to explore the effects of CNS drugs on food intake and energy expenditure

Obesity has reached epidemic proportions globally with an increasing incidence not just in Western cultures but also Mexico, Brazil, China and parts of Africa. In terms of pharmacological intervention, the track record of drug treatments for obesity is poor, especially in the case of centrally acting medicines, and there remains an unmet need for the development of safer compounds delivering superior efficacy. Animal models are of importance not only in detecting changes in food intake, energy expenditure and body weight but also providing confidence that these changes are behaviourally specific and not a result of drug-induced side effects. We review animal models of feeding behaviour that are used to aid our understanding of the control of body weight and energy regulation with special reference to CNS-acting drugs. The use of such models in the discovery of new drugs for the treatment of obesity is given particular emphasis. This article is part of a Special Issue entitled 'Central Control of Food Intake'.

The utility of animal models to evaluate novel anti-obesity agents

The global incidence of obesity continues to rise and is a major driver of morbidity and mortality through cardiovascular and cerebrovascular diseases. Animal models used in the discovery of novel treatments for obesity range from straightforward measures of food intake in lean rodents to long-term studies in animals exhibiting obesity due to the continuous access to diets high in fat. The utility of these animal models can be extended to determine, for example, that weight loss is due to fat loss and/or assess whether beneficial changes in key plasma parameters (e.g. insulin) are evident. In addition, behavioural models such as the behavioural satiety sequence can be used to confirm that a drug treatment has a selective effect on food intake. Typically, animal models have excellent predictive validity whereby drug-induced weight loss in rodents subsequently translates to weight loss in man. However, despite this, at the time of writing orlistat (Europe; USA) remains the only drug currently marketed for the treatment of obesity, with sibutramine having recently been withdrawn from sale globally due to the increased incidence of serious, non-fatal cardiovascular events. While the utility of rodent models in predicting clinical weight loss is detailed, the review also discusses whether animals can be used to predict adverse events such as those seen with recent anti-obesity drugs in the clinic.

Effects of low-dose, controlled-release, phentermine plus topiramate combination on weight and associated comorbidities in overweight and obese adults (CONQUER): a randomised, placebo-controlled, phase 3 trial

BACKGROUND

Obesity is associated with a reduction in life expectancy and an increase in mortality from cardiovascular diseases, cancer, and other causes. We therefore assessed the efficacy and safety of two doses of phentermine plus topiramate controlled-release combination as an adjunct to diet and lifestyle modification for weight loss and metabolic risk reduction in individuals who were overweight and obese, with two or more risk factors.

METHODS

In this 56-week phase 3 trial, we randomly assigned overweight or obese adults (aged 18-70 years), with a body-mass index of 27-45 kg/m(2) and two or more comorbidities (hypertension, dyslipidaemia, diabetes or prediabetes, or abdominal obesity) to placebo, once-daily phentermine 7·5 mg plus topiramate 46·0 mg, or once-daily phentermine 15·0 mg plus topiramate 92·0 mg in a 2:1:2 ratio in 93 centres in the USA. Drugs were administered orally. Patients were randomly assigned by use of a computer-generated algorithm that was implemented through an interactive voice response system, and were stratified by sex and diabetic status. Investigators, patients, and study sponsors were masked to treatment. Primary endpoints were the percentage change in bodyweight and the proportion of patients achieving at least 5% weight loss. Analysis was by intention to treat. This study is registered with Clinical Trials.gov, number NCT00553787.

FINDINGS

Of 2487 patients, 994 were assigned to placebo, 498 to phentermine 7·5 mg plus topiramate 46·0 mg, and 995 to phentermine 15·0 mg plus topiramate 92·0 mg; 979, 488, and 981 patients, respectively, were analysed. At 56 weeks, change in bodyweight was -1·4 kg (least-squares mean -1·2%, 95% CI -1·8 to -0·7), -8·1 kg (-7·8%, -8·5 to -7·1; p<0·0001), and -10·2 kg (-9·8%, -10·4 to -9·3; p<0·0001) in the patients assigned to placebo, phentermine 7·5 mg plus topiramate 46·0 mg, and phentermine 15·0 mg plus topiramate 92·0 mg, respectively. 204 (21%) patients achieved at least 5% weight loss with placebo, 303 (62%; odds ratio 6·3, 95% CI 4·9 to 8·0; p<0·0001) with phentermine 7·5 mg plus topiramate 46·0 mg, and 687 (70%; 9·0, 7·3 to 11·1; p<0·0001) with phentermine 15·0 mg plus topiramate 92·0 mg; for ≥10% weight loss, the corresponding numbers were 72 (7%), 182 (37%; 7·6, 5·6 to 10·2; p<0·0001), and 467 (48%; 11·7, 8·9 to 15·4; p<0·0001). The most common adverse events were dry mouth (24 [2%], 67 [13%], and 207 [21%] in the groups assigned to placebo, phentermine 7·5 mg plus topiramate 46·0 mg, and phentermine 15·0 mg plus topiramate 92·0 mg, respectively), paraesthesia (20 [2%], 68 [14%], and 204 [21%], respectively), constipation (59 [6%], 75 [15%], and 173 [17%], respectively), insomnia (47 [5%], 29 [6%], and 102 [10%], respectively), dizziness (31 [3%], 36 [7%], 99 [10%], respectively), and dysgeusia (11 [1%], 37 [7%], and 103 [10%], respectively). 38 (4%) patients assigned to placebo, 19 (4%) to phentermine 7·5 mg plus topiramate 46·0 mg, and 73 (7%) to phentermine 15·0 mg plus topiramate 92·0 mg had depression-related adverse events; and 28 (3%), 24 (5%), and 77 (8%), respectively, had anxiety-related adverse events.

INTERPRETATION

The combination of phentermine and topiramate, with office-based lifestyle interventions, might be a valuable treatment for obesity that can be provided by family doctors.

FUNDING

Vivus.

Well-being of obese individuals: therapeutic perspectives

The history of pharmacologic treatment of obesity is characterized by too much focus on efficacy and too little on safety, which has led to withdrawals of drugs from the market after serious adverse events. The development of new drug targets for the management of obesity will definitively need to address effects of the CNS and overall cardiovascular safety in the early stages in order to avoid the mistakes from the past. For instance, weight loss can increase the symptoms of depression and promote a state of psychobiological vulnerability favoring weight regain. Body-weight management should then seek a balance between the health benefits of weight loss and its potential risks, a ‘zone’ that is associated with an optimal psychobiological well-being.

Phentermine cardiovascular safety II: response to Yosefy Int J Cardiol. 2009 Epub Mar 19

This is the fourth in a series of letters-to-the-editor discussing phentermine and cardiovascular safety. Yosefy et al., in reporting a case of aortic cusp tear in a 28 year-old woman with a bicuspid aortic valve, attributed the tear to previous phentermine therapy. Evidence of mitral and tricuspid valve thickening was noted at echocardiography. In replying we pointed out that phentermine-induced valvular heart disease has not been reported and suggested that, since the reference cited for support referred to fenfluramine-induced valvulopathy, the attribution of the cusp tear to phentermine was incorrect. Yosefy replied, asserting that since the patient had no other cardiac risk factor, the tear had to be due to phentermine. In support of his presumption that phentermine therapy can induce cardiac risk he cited only the PDR warnings for phentermine. In this reply we point out that a congenital bicuspid valve should not be ignored as a cardiac risk factor, that aortic valve cusp tears have been associated with bicuspid valves but never with phentermine or with valve thickening no matter the etiology, and that there is no published data implicating phentermine as a cause of valve thickening (or any other valve pathology). Evidence of phentermine safety in the peer-reviewed medical literature is discussed in the context of the cardiovascular warnings for phentermine in the PDR.

Behavioral and pharmacologic therapies for obesity

This article reviews novel developments in the behavioral and pharmacologic treatment of obesity and explores the potential contribution of genomics research to weight control. A comprehensive program of lifestyle modification, comprised of diet, physical activity and behavior therapy, induces a mean loss of 7-10% of initial weight in individuals with obesity. Two trials demonstrated that weight loss of this magnitude, combined with increased physical activity, substantially reduced the risk of developing type 2 diabetes mellitus in individuals with impaired glucose tolerance. A third trial is now investigating whether lifestyle intervention will reduce cardiovascular morbidity and mortality in overweight individuals who already have diabetes mellitus. Pharmacotherapy is recommended, in some patients, as an adjunct to lifestyle modification. Two medications-orlistat and sibutramine-are currently approved in the US for long-term weight loss. Both are efficacious when combined with lifestyle modification, although health concerns have been raised about the use of sibutramine. Several novel combination therapies, which target multiple hypothalamic pathways that regulate appetite and body weight, are currently under investigation. Genomic studies provide further evidence for the role of these pathways in the regulation of body weight. Identification of new genes controlling satiety and energy expenditure may yield valuable clues for the development of novel pharmacologic treatments.

Current trends in targeting the hormonal regulation of appetite and energy balance to treat obesity

With the eruption of the obesity pandemic over the past few decades, much research has been devoted to understanding the molecular mechanisms by which the human body regulates energy balance. These studies have revealed several mediators, including gut/pancreatic/adipose hormones and neuropeptides that control both short- and long-term energy balance by regulating appetite and/or metabolism. These endogenous mediators of energy balance have been the focus of many anti-obesity drug-development programs aimed at either amplifying endogenous anorexigenic/lipolytic signaling or blocking endogenous orexigenic/lipogenic signaling. Here, we discuss the efficacy and safety of targeting these pathways for the pharmacologic treatment of obesity.

Pharmacologic therapies for obesity

This article examines the transitions in pharmacological therapy for obesity. It reviews the current options approved by the Food and Drug Administration and several drugs approved for other indications that can be used to treat obesity as well. Because weight regulation is complex and redundant systems protect against perceived starvation, optimal treatment of obesity in individual patients will likely require different combinations of behavioral, nutritional, pharmacologic, endoscopic, and surgical therapies.