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South African Medical Journal =... Aug 2023Phentermine is an internationally recognised amphetamine derivative with significant appetite-suppressing properties. The drug is indicated for the short-term management...
BACKGROUND
Phentermine is an internationally recognised amphetamine derivative with significant appetite-suppressing properties. The drug is indicated for the short-term management of obesity, as the long-term (LT) use of phentermine may potentially be associated with severe cardiovascular side-effects, abuse and dependence. The LT use hereinafter describes periods exceeding 12 consecutive weeks. This use may also be associated with potential drug-drug interactions (PDDIs), which may result in adverse drug reactions (ADRs). The literature reports that phentermine is often prescribed LT and for several other off-label indications, increasing the risk for individuals to experience adverse drug events (ADEs) and drug-drug interactions (DDIs). There are, to our knowledge, no South African (SA) studies investigating the prevalence of co-prescribing LT phentermine with drugs that may potentially cause DDIs.
OBJECTIVE
To determine the prevalence of mild, moderate and severe DDIs with phentermine use when the duration of therapy in private healthcare exceeded 12 consecutive weeks.
METHODS
A cross-sectional drug utilisation review (DUR) was done by using data obtained from a SA pharmacy benefit management (PBM) company's database. Retrospective data of medicine claims for phentermine, from 1 January 2015 to 31 December 2019, were extracted for analysis. The number of days phentermine was supplied was used to identify the study population, in other words, those patients who received the drug LT. A drug interaction checker (Drugs.com) was used to identify potential mild, moderate and severe DDIs when using phentermine and co-prescribed drugs concurrently.
RESULTS
A total of 889 patients received phentermine LT. The top 20 drugs identified as being frequently co-prescribed in this study population demonstrated no mild PDDI, 15 (75%) moderate PDDIs and 5 (25%) severe PDDIs. The most common co-prescribed drug in the moderate group was dextromethorphan (n=282, 31.72%) and the least co-prescribed was formoterol (n=52, 5.85%). Among the drug group 'severe PDDIs', tramadol (n=416, 46.79%) was most frequently prescribed, whereas phenylpropanolamine (n=69, 7.76%) was the least prescribed to patients in this group.
CONCLUSION
There are patients who receive LT phentermine therapy despite the potential severe consequences that may result. These patients may receive concomitant therapy with phentermine and other pharmaceutical constituents, which may potentially cause DDIs, more specifically, moderate and severe DDIs. As such, these patients are not only confronted with the consequences of DDIs but are also at risk to experience ADRs as the residual effect of PDDIs.
Topics: Humans; Phentermine; Retrospective Studies; Cross-Sectional Studies; South Africa; Drug-Related Side Effects and Adverse Reactions; Drug Interactions
PubMed: 37882119
DOI: 10.7196/SAMJ.2023.v113i8.428 -
JAMA Network Open Oct 2023Although the American Academy of Pediatrics has recommended treatment with antiobesity drugs for adolescents, the cost-effectiveness of antiobesity drugs for this...
IMPORTANCE
Although the American Academy of Pediatrics has recommended treatment with antiobesity drugs for adolescents, the cost-effectiveness of antiobesity drugs for this population is still unknown.
OBJECTIVE
To quantify cost-effectiveness of different antiobesity drugs available for pediatric use.
DESIGN, SETTING, AND PARTICIPANTS
This economic evaluation used a Markov microsimulation model with health states defined by obesity levels. Effectiveness was measured by quality-adjusted life-years (QALYs) and costs were calculated from third-party payer perspective, estimated in 2023 US dollars over a 10-year horizon. Data were obtained from the published literature.
INTERVENTION
Antiobesity drugs orlistat, liraglutide, semaglutide, and phentermine-topiramate vs no treatment. Metformin hydrochloride and 2 types of bariatric surgical procedures (sleeve gastrectomy and gastric bypass) were considered in sensitivity analysis.
MAIN OUTCOMES AND MEASURES
Incremental cost-effectiveness ratio.
RESULTS
Among the 4 antiobesity drugs currently approved for pediatric use, phentermine-topiramate was the most cost-effective with an incremental cost-effectiveness ratio of $93 620 per QALY relative to no treatment in this simulated cohort of 10 000 adolescents aged 12 to 17 years (mode, 15 years) with severe obesity (62% female). While semaglutide offered more QALYs than phentermine-topiramate, its higher cost resulted in an incremental cost-effectiveness ratio ($1 079 480/QALY) that exceeded the commonly used willingness-to-pay threshold of $100 000 to $150 000/QALY. Orlistat and liraglutide cost more and were less effective than phentermine-topiramate and semaglutide, respectively. Sleeve gastrectomy and gastric bypass were more effective than phentermine-topiramate but were also more costly, rendering them not cost-effective compared with phentermine-topiramate at the willingness-to-pay threshold of $100 000 to $150 000/QALY.
CONCLUSIONS AND RELEVANCE
In this economic evaluation of weight loss drugs for adolescents with severe obesity, we found phentermine-topiramate to be a cost-effective treatment at a willingness-to-pay threshold of $100 000 to $150 000/QALY. Further research is needed to determine long-term drug efficacy and how long adolescents continue treatment.
Topics: Humans; Female; Adolescent; Child; Male; Anti-Obesity Agents; Obesity, Morbid; Cost-Benefit Analysis; Orlistat; Topiramate; Liraglutide; Obesity; Phentermine
PubMed: 37824146
DOI: 10.1001/jamanetworkopen.2023.36400 -
Psychiatry Investigation Sep 2023Phentermine is a commonly used weight-loss agent in the United States, but there is a little information about the use of phentermine for patients with obesity taking...
OBJECTIVE
Phentermine is a commonly used weight-loss agent in the United States, but there is a little information about the use of phentermine for patients with obesity taking antipsychotic medications.
METHODS
We gathered 57 patients with obesity taking antipsychotic medications whose phentermine treatment was simultaneous with or after any type of antipsychotic exposure and collected data of clinical information, initial/follow-up anthropometric variables, and adverse events (AEs) for the 6-month study period.
RESULTS
In total, the mean body weight reduction (BWR) was 4.45 (7.04) kg, and the mean BWR percent (BWR%) was 3.92% (6.96%) at 6 months. Based on the response to phentermine, the patients were classified into two groups: the responder (n=25; BWR% ≥5%) and nonresponder (n=32; BWR% <5%) groups. The responder group's mean BWR and BWR% were 10.13 (4.43) kg and 9.35% (4.09%), respectively, at 6 months. The responders had higher rates of anticonvulsant combination therapy (ACT; responder, 72.0% vs. non-responder, 43.8%; p=0.033) and a shorter total antipsychotic exposure duration (responder, 23.9 [16.9] months vs. non-responder, 37.2 [27.6] months; p= 0.039). After adjusting age, sex, and initial body weight, ACT maintained a significant association with phentermine response (odds ratio=3.840; 95% confidence interval: 1.082-13.630; p=0.037). In the final cohort, there was no report of adverse or new-onset psychotic symptoms, and the common AEs were sleep disturbances, dry mouth, and dizziness.
CONCLUSION
Overall, phentermine was effective and tolerable for patients with obesity taking antipsychotic medications, and ACT (predominantly topiramate) augmented the weight-loss effect of phentermine.
PubMed: 37794661
DOI: 10.30773/pi.2023.0045 -
Romanian Journal of Internal Medicine =... Mar 2024Obesity and overweight are the major risk factors for numerous chronic diseases, including cardiovascular diseases such as heart disease and stroke, which are the... (Review)
Review
Obesity and overweight are the major risk factors for numerous chronic diseases, including cardiovascular diseases such as heart disease and stroke, which are the leading causes of death worldwide. The prevalence of obesity has dramatically risen in both developed and developing countries, making it a significant public health concern and a global crisis. Despite lifestyle modifications being the first-line treatment, the high risk of relapse has led to a growing interest in non-invasive pharmacotherapeutic interventions to achieve and maintain weight loss and reverse the growth of the obesity epidemic. Cardiovascular diseases and cancer account for the highest mortality rates among other comorbidities associated with obesity and overweight. Excess and abnormally deposited adipose tissue secretes various inflammatory mediators, leading to cardiovascular diseases and cancers. Weight loss of 5-10% significantly reduces cardiometabolic risk. Medications currently approved in the USA for long-term management of obesity are orlistat, naltrexone, bupropion, phentermine/topiramate, and Glucagon Like Peptide-1 (GLP-1) agonists such as liraglutide and semaglutide. The benefit-to-risk of medications, comorbidities, and individual responses should guide the treatment decisions. The article provides a comprehensive overview and discussion of several weight loss medications used previously and currently, including their efficacy, mechanisms of action, and side effects.
Topics: Humans; Overweight; Cardiovascular Diseases; Obesity; Anti-Obesity Agents; Weight Loss
PubMed: 37752761
DOI: 10.2478/rjim-2023-0023 -
Saudi Pharmaceutical Journal : SPJ :... Oct 2023Recently, many drugs have been approved for halting overweight and obesity-few types of research shifted to using Anti-obesity medications (AOM) solely for well-being... (Review)
Review
BACKGROUND
Recently, many drugs have been approved for halting overweight and obesity-few types of research shifted to using Anti-obesity medications (AOM) solely for well-being and shape-keeping.
OBJECTIVE
This narrative review's objective was to explore the use of AOM in relation to their medical indications, efficacy, and cardiovascular safety.
METHODS AND MATERIALS
We have conducted a narrative review of the literature on approved/non-approved AOM used for obesity and overweight. We have shed light on the emerging trials of therapies and evolving remedies.
RESULTS
Recently, there has been an enormous change in the use of AOM with high consumption that deserves extensive surveillance for the long-term consequences and impact on social, mental, and physical health. Nearly six AOMs and combined therapy are approved by the Food and Drug Administration. The recent guidelines for obesity management have shifted the focus from weight loss to goals that the patient considers essential and toward targeting the root cause of obesity.
CONCLUSION
The use of AOM increased enormously despite its sometimes-dubious safety and ineffectiveness. The public and medical professionals should be vigilant to the real-world benefits of anti-obesity drugs and their achieved effectiveness with an improved safety profile.
PubMed: 37712012
DOI: 10.1016/j.jsps.2023.101757 -
Journal of Global Health Sep 2023Despite rising concerns regarding the safety of anti-obesity medications, there is a lack of comprehensive pharmacovigilance investigations utilising real-world data. We...
INTRODUCTION
Despite rising concerns regarding the safety of anti-obesity medications, there is a lack of comprehensive pharmacovigilance investigations utilising real-world data. We aimed to characterise the prevalence and seriousness of adverse drug events (ADEs) related to anti-obesity medications and to identify predictors associated with increased risk of serious adverse events (SAE), thereby conveying evidence on drug safety.
METHODS
We conducted a cross-sectional analysis on ADE cases spontaneously reported to the Korea Adverse Event Reporting System Database (KIDS-KD). ADE reports pertaining to anti-obesity medications prescribed for overweight, obesity (International Classification of Disease, 10th revision (ICD-10) code E66) and abnormal weight gain (ICD-10 code E63.5) were included in the analysis. We performed a disproportionality to detect the association of the system organ class-based ADEs with their seriousness an individual's sex by estimating reporting odds ratios (RORs) and their 95% confidence intervals (CIs). We performed logistic regression to investigate factors that are substantially associated with increased SAE risks by estimating odds ratio (OR) and their 95% CIs.
RESULTS
The most common causative anti-obesity medication was phentermine, followed by liraglutide. ADEs associated with psychiatric disorders (ROR = 1.734; 95% CI = 1.111-2.707), liver and biliary system disorders (ROR = 22.948; 95% CI = 6.613-70.635), cardiovascular disorders (ROR = 5.707; 95% CI = 1.965-16.574), and respiratory disorders (ROR = 4.567; 95% CI = 1.774-11.762) were more likely to be serious events. Additionally, men are more likely to experience ADEs related gastrointestinal disorders (ROR = 1.411) and less likely to have heart and rhythm disorders (ROR = 0.507). The risk of SAE incidences was positively correlated with being male (OR = 2.196; 95% CI = 1.296-3.721), dual or triple combination of anti-obesity medications (OR = 3.258; 95% CI = 1.633-6.501 and OR = 8.226; 95% CI = 3.046-22.218, respectively), and concomitant administration of fluoxetine (OR = 5.236; 95% CI = 2.218-12.365).
CONCLUSIONS
Seriousness of anti-obesity medication-related ADEs differs among system-organ class, while sex-related differences in ADE profiles are also present. The predictors substantially increasing risk of SAE incidences include being male, having a higher number of concomitant medications (including multiple combination of anti-obesity medications), and concurrent use of fluoxetine. Nonetheless, further pharmacovigilance investigation and monitoring are needed to enhance awareness on ADEs induced by anti-obesity medications.
Topics: Humans; Male; Female; Cross-Sectional Studies; Fluoxetine; Pharmacovigilance; Obesity; Cardiovascular Diseases
PubMed: 37651636
DOI: 10.7189/jogh.13.04095 -
JAMA Network Open Aug 2023Antiobesity pharmacotherapy is recommended for adolescents ages 12 years and older with obesity. Several medications have been approved by the US Food and Drug...
IMPORTANCE
Antiobesity pharmacotherapy is recommended for adolescents ages 12 years and older with obesity. Several medications have been approved by the US Food and Drug Administration for adolescent use, but the most cost-effective medication remains unclear.
OBJECTIVE
To estimate the cost-effectiveness of lifestyle counseling alone and as adjunct to liraglutide, mid-dose phentermine and topiramate (7.5 mg phentermine and 46 mg topiramate), top-dose phentermine and topiramate (15 mg phentermine and 92 mg topiramate), or semaglutide among adolescent patients with obesity.
DESIGN, SETTING, AND PARTICIPANTS
This economic evaluation used a microsimulation model to project health and cost outcomes of lifestyle counseling alone and adjunct to liraglutide, mid-dose phentermine and topiramate, top-dose phentermine and topiramate, or semaglutide over 13 months, 2 years, and 5 years among a hypothetical cohort of 100 000 adolescents with obesity, defined as an initial body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) of 37. Model inputs were derived from clinical trials, published literature, and national sources. Data were analyzed from April 2022 to July 2023.
EXPOSURES
Lifestyle counseling alone and as adjunct to liraglutide, mid-dose phentermine and topiramate, top-dose phentermine and topiramate, or semaglutide.
MAIN OUTCOMES AND MEASURES
The main outcome was quality-adjusted life years (QALYs), costs (2022 US dollars), and incremental cost-effectiveness ratios (ICERs), with future costs and QALYs discounted 3.0% annually. A strategy was considered cost-effective if the ICER was less than $100 000 per QALY gained. The preferred strategy was determined as the strategy with the greatest increase in QALYs while being cost-effective. One-way and probabilistic sensitivity analyses were used to assess parameter uncertainty.
RESULTS
The model simulated 100 000 adolescents at age 15 with an initial BMI of 37, of whom 58 000 (58%) were female. At 13 months and 2 years, lifestyle counseling was estimated to be the preferred strategy. At 5 years, top-dose phentermine and topiramate was projected to be the preferred strategy with an ICER of $56 876 per QALY gained vs lifestyle counseling. Semaglutide was projected to yield the most QALYs, but with an unfavorable ICER of $1.1 million per QALY gained compared with top-dose phentermine and topiramate. Model results were most sensitive to utility of weight reduction and weight loss of lifestyle counseling and top-dose phentermine and topiramate.
CONCLUSIONS AND RELEVANCE
In this economic evaluation of pharmacotherapy for adolescents with obesity, top-dose phentermine and topiramate as adjunct to lifestyle counseling was estimated to be cost-effective after 5 years. Long-term clinical trials in adolescents are needed to fully evaluate the outcomes of pharmacotherapy, especially into adulthood.
Topics: United States; Adolescent; Humans; Female; Male; Cost-Benefit Analysis; Pediatric Obesity; Topiramate; Liraglutide; Phentermine
PubMed: 37651143
DOI: 10.1001/jamanetworkopen.2023.29178 -
Adolescent Health, Medicine and... 2023The prevalence of pediatric obesity has increased exponentially over the past four decades. The American Academy of Pediatrics recently released updated clinical... (Review)
Review
The prevalence of pediatric obesity has increased exponentially over the past four decades. The American Academy of Pediatrics recently released updated clinical practice guidelines highlighting the importance of identifying pediatric obesity as a chronic disease. The guidelines support consideration of concurrent treatment with intensive lifestyle interventions, obesity pharmacotherapy, and bariatric surgery. The dramatic rise in pediatric obesity has spurred interest in utilizing obesity pharmacotherapy to support sustained weight reduction in pediatric cohorts, in the hopes of preventing the emergence of later-appearing, significant co-morbidities. Despite the enormous demand, the obstacles posed by performance of needed clinical trials in the pediatric population markedly limits available pharmacotherapy for the treatment of obesity in pediatrics. Currently, there are five medications approved by the Food and Drug Administration for use in youth with obesity. In 2022, the phentermine/topiramate (PHEN/TPM), once-daily, controlled-release, combination product received FDA approval, for the indication of chronic weight management, in youth with obesity, ages 12 years and older. The objectives of this narrative review are to: (1) Review the mechanism of action of phentermine and topiramate, (2) Summarize the safety and efficacy data of topiramate and phentermine use as both monotherapies and in combination, and (3) Discuss clinical practice guidelines and clinical implications, for the use of these agents in youths with obesity.
PubMed: 37641650
DOI: 10.2147/AHMT.S383454 -
Journal of Managed Care & Specialty... Oct 2023Primary nonadherence (PNA), when a medication is newly prescribed but not filled, has been identified as a major research gap potentially impacting the optimal...
Primary nonadherence (PNA), when a medication is newly prescribed but not filled, has been identified as a major research gap potentially impacting the optimal treatment of patients with overweight and obesity who are newly prescribed antiobesity medications (AOMs). To assess PNA among patients with newly prescribed AOMs and to examine factors associated with PNA to AOMs. This was a retrospective study that used the Optum Integrated Clinical plus Claims database to identify individuals who had at least 1 prescription order for an AOM the US Food and Drug Administration approved for long-term use. Individuals with prescription orders between January 1, 2012, and February 28, 2019, were identified, and patient demographics, clinical characteristics, medication prescribed, baseline health care utilization, and obesity-related complications were described by PNA status. PNA was defined as no pharmacy claim for the AOM within 60 days of the date of the new prescription order as identified in electronic health record data. A multivariable logistic regression model was used to examine factors associated with PNA. The study sample included a total of 1,563 patients. The mean body mass index was 38.4 kg/m; 10.7% were prescribed liraglutide 3.0 mg, 26.0% were prescribed lorcaserin, 36.3% of patients were prescribed naltrexone-bupropion, 5.4% were prescribed orlistat, and 21.6% were prescribed phentermine-topiramate. Most patients (91.1%) exhibited PNA, with only 8.9% filling their newly prescribed AOM within 60 days. Both the adherent and nonadherent groups were predominately female sex, White, and covered by commercial insurance. The mean age was similar between the 2 groups. Most obesity-related complications were less prevalent in the adherent group, although the Charlson comorbidity index score was similar between the 2 groups. After adjustment for patient demographics and clinical characteristics, there was not a statistically significant association between the specific AOM and PNA ( = 0.299). Patients with depression or living in the Midwest or South regions were at significantly increased risk of PNA. The rate of PNA to AOMs was very high, suggesting barriers in effective medical management of patients with overweight and obesity. Future research is warranted to understand reasons for PNA to AOMs and how to address these barriers. Dr Kan, Dr Bae, Dr Dunn, and Dr Ahmad are employees of Eli Lilly and Company. Ms Buysman and Dr Gronroos are employees of Optum. Dr Swindle was an employee of Optum at the time the study was conducted and is currently employed at Evidera. Dr Bengtson is employed at Boehringer Ingelheim Pharmaceuticals, Inc. (Boehringer Ingelheim has no connection to this study), and during the conduct of this study was employed at Optum.
Topics: Humans; Female; Retrospective Studies; Overweight; Anti-Obesity Agents; Obesity; Delivery of Health Care
PubMed: 37594848
DOI: 10.18553/jmcp.2023.23083 -
Journal of Medicinal Chemistry Aug 2023The cardiotoxicity associated with -ethyl-dexfenfluramine (norDF) and related agonists of the serotonin receptor 2B (5-HT) has solidified the receptor's place as an... (Review)
Review
The cardiotoxicity associated with -ethyl-dexfenfluramine (norDF) and related agonists of the serotonin receptor 2B (5-HT) has solidified the receptor's place as an "antitarget" in drug discovery. Conversely, a growing body of evidence has highlighted the utility of 5-HT antagonists for the treatment of pulmonary arterial hypertension (PAH), valvular heart disease (VHD), and related cardiopathies. In this Perspective, we summarize the link between the clinical failure of fenfluramine-phentermine (fen-phen) and the subsequent research on the role of 5-HT in disease progression, as well as the development of drug-like and receptor subtype-selective 5-HT antagonists. Such agents represent a promising class for the treatment of PAH and VHD, but their utility has been historically understudied due to the clinical disasters associated with 5-HT. Herein, it is our aim to examine the current state of 5-HT drug discovery, with an emphasis on the receptor's role in the central nervous system (CNS) versus the periphery.
Topics: Humans; Receptor, Serotonin, 5-HT2B; Serotonin; Fenfluramine; Heart Valve Diseases; Drug Discovery
PubMed: 37584406
DOI: 10.1021/acs.jmedchem.3c01178