Weight Loss Pharmacotherapy: Current and Future Therapies.

The rising prevalence of obesity is of major concern. There are currently 5 Food and Drug Administration-approved medications for the treatment of obesity: orlistat, phentermine/topiramate, naltrexone/bupropion, liraglutide 3.0 mg, and semaglutide 2.4 mg. Surgical options such as bariatric surgery and endoscopic surgery induce more durable weight loss than pharmacotherapy or lifestyle interventions alone. However, patients often experience weight regain and weight loss plateau after surgery. The addition of multimodal or multihormonal pharmacotherapy is a promising tool to address these challenges. The optimal timing of obesity pharmacotherapy with surgical and endoscopic interventions requires further investigation.

Medications for Obesity: A Review.

Importance: Obesity affects approximately 19% of women and 14% of men worldwide and is associated with increased morbidity. Antiobesity medications (AOMs) modify biological processes that affect appetite and significantly improve outcomes, such as type 2 diabetes, hypertension, and dyslipidemia. Observations: AOMs should be administered in combination with lifestyle interventions and can be classified according to their mechanisms of action. Orlistat modifies digestive tract absorption and causes gastrointestinal adverse effects, such as oily fecal spotting and urgency, in more than 25% of patients. Centrally acting drugs, such as phentermine-topiramate and naltrexone-bupropion, regulate appetite in the brain and are associated with constipation in approximately 20% of patients, although the incidence of other adverse effects (eg, paresthesia, nausea) varies by medication. Nutrient-stimulated hormone-based medications, such as liraglutide, semaglutide, and tirzepatide, mimic the actions of enteropancreatic hormones that modify central appetite regulation and provide multiple cardiometabolic weight-loss benefits. Adverse effects of these drugs include nausea (28%-44%), diarrhea (21%-30%), and constipation (11%-24%). The relative potency of adult obesity medications has been studied in meta-analyses. Compared with placebo, orlistat was associated with 3.1% greater weight loss (52 randomized clinical trials [RCTs]; 16 964 participants), phentermine-topiramate was associated with 8.0% greater weight loss (5 RCTs; 3407 participants), naltrexone-bupropion was associated with 4.1% greater weight loss (6 RCTs; 9949 participants), liraglutide was associated with 4.7% greater weight loss (18 RCTs; 6321 participants), semaglutide was associated with 11.4% greater weight loss (5 RCTs; 4421 participants), and tirzepatide 15 mg was associated with 12.4% greater weight loss (6 RCTs; 1972 participants). Conclusion and Relevance: Obesity is associated with increased morbidity. Antiobesity medications are effective adjunctive therapy to lifestyle changes for improved weight loss and health outcomes.

Analysis of Prescription Trends for Narcotic Appetite Suppressants: Utilizing the Narcotics Information Management System.

PURPOSE: The aim of this study was to systematically analyze the prescription trends of medical narcotic appetite suppressants in South Korea. MATERIALS AND METHODS: Data was extracted from the Narcotics Information Management System dataset from 2020, which encompasses nationwide information concerning the use of medical narcotics. The selected variables for this study included the types of prescribed medical narcotic appetite suppressants, gender, age, region, and the category of medical institution. Regional prescription trends were compared by utilizing the defined daily doses for statistical purposes (S-DDD). RESULTS: The prescription of medical narcotic appetite suppressants was predominantly for females (94%), with the highest prescription rates identified in the 30-40 age group. The majority of these prescriptions were dispensed by clinics. Within the category of narcotic appetite suppressants, phentermine and phendimetrazine were found to have higher prescription rates. Notably, the region of Daegu recorded the highest S-DDD value (12.66) in phentermine consumption. CONCLUSION: Our findings underscore the need for governmental policy and guidance to address the risks linked to the long-term use of medical narcotic appetite suppressants. This is crucial to ensure their safe and efficacious prescription and administration.

Effectiveness and predictors of weight loss response to phentermine plus lifestyle modifications among youth in a paediatric weight management clinical setting.

BACKGROUND: Anti-obesity medications (AOMs) are promising lifestyle modification (LSM) adjuncts for obesity treatment, and phentermine is commonly prescribed in paediatric weight management clinics. Determining 'real-world' AOM effectiveness and characteristics predicting response is important. OBJECTIVES: We sought to describe phentermine plus LSM effectiveness and identify baseline characteristics predicting response. METHODS: This was a retrospective cohort study among youth seen in a US academic-based weight management clinic from 2012 to 2020. Baseline characteristics (e.g., body mass index (BMI), liver transaminases, eating-related behaviours) and outcomes (%BMI of 95th percentile (%BMIp95), BMI, %BMI change, weight) were determined through electronic health records and intake surveys. RESULTS: Among 91 youth prescribed phentermine plus LSM over 8 years (mean %BMIp95 150%), %BMIp95 was statistically significantly reduced at 1.5, 3, 6 and 12 months (peak reduction 10.9 percentage points at 6 months; p < 0.001). Considering multiple comparisons, the presence of baseline elevated alanine aminotransferase was associated with statistically significant smaller 1.5-month %BMIp95 reductions (p = 0.001) and higher food responsiveness with smaller 3- (p = 0.001) and 6-month (p < 0.001) reductions. CONCLUSIONS: Phentermine plus LSM reduced %BMIp95 among youth in a weight management clinic, and baseline characteristics may help determine those more or less likely to respond. Prospective studies are needed to further characterize effectiveness and confirm response predictors.

Pharmacotherapy for adults with overweight and obesity: a systematic review and network meta-analysis of randomised controlled trials.

BACKGROUND: Pharmacotherapy provides an option for adults with overweight and obesity to reduce their bodyweight if lifestyle modifications fail. We summarised the latest evidence for the benefits and harms of weight-lowering drugs. METHODS: This systematic review and network meta-analysis included searches of PubMed, Embase, and Cochrane Library (CENTRAL) from inception to March 23, 2021, for randomised controlled trials of weight-lowering drugs in adults with overweight and obesity. We performed frequentist random-effect network meta-analyses to summarise the evidence and applied the Grading of Recommendations Assessment, Development, and Evaluation frameworks to rate the certainty of evidence, calculate the absolute effects, categorise interventions, and present the findings. The study was registered with PROSPERO, CRD 42021245678. FINDINGS: 14 605 citations were identified by our search, of which 132 eligible trials enrolled 48 209 participants. All drugs lowered bodyweight compared with lifestyle modification alone; all subsequent numbers refer to comparisons with lifestyle modification. High to moderate certainty evidence established phentermine-topiramate as the most effective in lowering weight (odds ratio [OR] of ≥5% weight reduction 8·02, 95% CI 5·24 to 12·27; mean difference [MD] of percentage bodyweight change -7·98, 95% CI -9·27 to -6·69) followed by GLP-1 receptor agonists (OR 6·33, 95% CI 5·00 to 8·00; MD -5·79, 95% CI -6·34 to -5·25). Naltrexone-bupropion (OR 2·69, 95% CI 2·10 to 3·44), phentermine-topiramate (2·40, 1·68 to 3·44), GLP-1 receptor agonists (2·22, 1·74 to 2·84), and orlistat (1·71, 1·42 to 2·05) were associated with increased adverse events leading to drug discontinuation. In a post-hoc analysis, semaglutide, a GLP-1 receptor agonist, showed substantially larger benefits than other drugs with a similar risk of adverse events as other drugs for both likelihood of weight loss of 5% or more (OR 9·82, 95% CI 7·09 to 13·61) and percentage bodyweight change (MD -11·40, 95% CI -12·51 to -10·29). INTERPRETATION: In adults with overweight and obesity, phentermine-topiramate and GLP-1 receptor agonists proved the best drugs in reducing weight; of the GLP-1 agonists, semaglutide might be the most effective. FUNDING: 1.3.5 Project for Disciplines of Excellence, West China Hospital, Sichuan University.

[Current State of Pharmacotherapy in Obesity].

The prevalence of obesity with various complications is increasing rapidly in Korea. Although lifestyle modification is fundamental in obesity treatment, more effective treatment tools are required. Many advances in obesity treatment have been reported recently, including lifestyle modifications and pharmacological, endoscopic, and surgical treatments. Drugs with proven long-term efficacy and safety are preferred because management for obesity treatment is a long-term process. Currently, four medications are available for long-term use in Korea: Orlistat, Naltrexone/bupuropion NR, Phentermine/topiramate capsule, and Liraglutide. Recently, semaglutide and tirzepatide have been attracting attention because of their effectiveness and convenience, but they are not yet available in Korea. In addition, there are limitations such as the yo-yo effect when discontinuing the drug, long-term safety, and cost. Patients and medical staff must be aware of the advantages and side effects of each medication to ensure the successful treatment of obesity.

Comparison of the Efficacy of Anti-Obesity Medications in Real-World Practice.

Purpose: Anti-obesity medications (AOMs), along with lifestyle interventions, are effective means of inducing and maintaining weight loss in patients with obesity. Although the efficacy of AOMs has been reported, there have been no direct comparisons of these drugs. Therefore, in the present study, we aimed to compare the efficacy of all the AOMs available in Korea in a real-world setting. Patients and Methods: The body weight and composition of 205 adults treated with phentermine, phentermine/topiramate, liraglutide, naltrexone/bupropion, lorcaserin, or orlistat for at least 6 months were analyzed at 2 month intervals. The prevalence of the achievement of a ≥5% weight loss and the changes in body composition were compared between participants using each AOM at each visit. Results: A total of 132 (64.4%) participants achieved ≥5% weight loss within 6 months (prevalence of ≥5% weight loss after 6 months: phentermine, 87.2%; phentermine/topiramate, 67.7%; liraglutide, 58.1%; naltrexone/bupropion, 35.3%; lorcaserin, 75%; orlistat, 50%). At each visit, after adjustment for age, sex, and baseline body weight, phentermine use was associated with a significantly higher prevalence of ≥5% weight loss than the use of the other AOMs, except for liraglutide. There were significant differences in the body weight, body mass index and body fat mass among the AOM groups by visit (P for interaction <0.05), but not in their waist circumference, skeletal muscle mass, percentage body fat, or visceral fat area. Conclusion: All the AOMs were effective at inducing and maintaining weight loss, in the absence of significant changes in muscle mass, over a 6 month period, and the short-term use of phentermine and the long-term use of phentermine/topiramate or liraglutide would be practical choices for the treatment of obesity. However, further, large-scale studies are necessary to confirm these findings.

Utilization of Anti-obesity Medications After Bariatric Surgery: Analysis of a Large National Database.

PURPOSE: A significant proportion of patients experience insufficient weight loss or weight regain after bariatric surgery. There is a paucity of literature describing anti-obesity medication (AOM) use following bariatric surgery. We sought to identify prevalence and trends of AOM use following bariatric surgery. MATERIALS AND METHODS: We utilized the IBM Explorys® database to identify all adults with prior bariatric surgery (Roux-en-Y gastric bypass or sleeve gastrectomy). Those prescribed AOMs (semaglutide, liraglutide, topiramate, phentermine/topiramate, naltrexone/bupropion, orlistat) within 5 years of surgery were further identified. Data was analyzed to characterize AOM utilization among different age, demographic, and comorbid populations. RESULTS: A total of 59,160 adults with prior bariatric surgery were included. Among AOMs studies, prevalence of use was highest for topiramate (8%), followed by liraglutide (2.9%), phentermine/topiramate (1.03%), naltrexone/bupropion (0.95%) semaglutide (0.52%), and orlistat (0.17%). Age distribution varied, with the highest utilization among those age 35-39 years for topiramate, 40-44 years for phentermine/topiramate and naltrexone/bupropion, 45-49 years for semaglutide, and 65-69 years for liraglutide and orlistat. African American race was associated with higher utilization across all AOMs. Among comorbidities, hypertension, hyperlipidemia, and diabetes mellitus were most associated with AOM use. CONCLUSION: Despite a relatively high incidence of weight regain, AOMs are underutilized following bariatric surgery. It is imperative that barriers to their use be addressed and that AOMs be considered earlier and more frequently in patients with insufficient weight loss or weight regain after bariatric surgery.

Phentermine in the Modern Era of Obesity Pharmacotherapy: Does It Still Have a Role in Treatment?

PURPOSE OF REVIEW: This review provides an overview of the history, mechanism of action, and expected treatment effects of the anti-obesity medication (AOM), phentermine. It also includes a summary of recent research and practical guidance for prescribing clinicians. RECENT FINDINGS: Recent research on phentermine is sparse and consists primarily of observational studies with methodologic limitations. These studies suggest that phentermine use is associated with clinically significant weight loss in adults and that the medication is generally well tolerated. Large-scale observational studies evaluating phentermine's safety have not identified an increased risk of cardiovascular events or elevations in blood pressure. There is no data to support the notion that phentermine is addictive. Although it remains the most commonly prescribed AOM in the USA, phentermine has little rigorous research to support its efficacy and safety in long-term treatment, which creates a dilemma with guideline-recommended chronic use of AOMs. While we await forthcoming conclusive data on this front, clinicians may consider using phentermine long-term in selected patients, if such prescribing is consistent with local regulatory statutes.

Association of patient characteristics and insurance type with anti-obesity medications prescribing and fills.

AIM: To characterize factors associated with the receipt of anti-obesity medication (AOM) prescription and fill. MATERIALS AND METHODS: This retrospective cohort study used electronic health records from 1 January 2015 to 30 June 2023, in a large health system in Ohio and Florida. Adults with a body mass index ≥30 kg/m2 who attended ≥1 weight-management programme or had an initial AOM prescription between 1 July 2015 and 31 December 2022, were included. The main measures were a prescription for an AOM (naltrexone-bupropion, orlistat, phentermine-topiramate, liraglutide 3.0 mg and semaglutide 2.4 mg) and an AOM fill during the study follow-up. RESULTS: We identified 50 678 adults, with a mean body mass index of 38 ± 8 kg/m2 and follow-up of 4.7 ± 2.4 years. Only 8.0% of the cohort had AOM prescriptions and 4.4% had filled prescriptions. In the multivariable analyses, being a man, Black, Hispanic and other race/ethnicity (vs. White), Medicaid, traditional Medicare, Medicare Advantage, self-pay and other insurance types (vs. private insurance) and fourth quartile of the area deprivation index (vs. first quartile) were associated with lower odds of a new prescription. Hispanic ethnicity, being a man, Medicaid, traditional Medicare and Medicare Advantage insurance types, liraglutide and orlistat (vs. naltrexone-buproprion) were associated with lower odds of AOM fill, while phentermine-topiramate was associated with higher odds. Among privately insured individuals, the insurance carrier was associated with both the odds of AOM prescription and fill. CONCLUSIONS: Significant disparities exist in access to AOM both at the prescribing stage and getting the prescription filled based on patient characteristics and insurance type.

SMART use of medications for the treatment of adolescent severe obesity: A sequential multiple assignment randomized trial protocol.

BACKGROUND: Severe obesity is a complex, chronic disease affecting nearly 9% of adolescents in the U.S. Although the current mainstay of treatment is lifestyle therapy, pediatric clinical practice guidelines recommend the addition of adjunct anti-obesity medication (AOM), such as phentermine and topiramate. However, guidance regarding when adjunct AOM should be started and how AOM should be used is unclear. Furthermore, an inherent limitation of current treatment guidelines is their "one-size-fits-all" approach, which does not account for the heterogeneous nature of obesity and high degree of patient variability in response to all interventions. METHODS: This paper describes the study design and methods of a sequential multiple assignment randomized trial (SMART), "SMART Use of Medications for the Treatment of Adolescent Severe Obesity." The trial will examine 1) when to start AOM (specifically phentermine) in adolescents who are not responding to lifestyle therapy and 2) how to modify AOM when there is a sub-optimal response to the initial pharmacological intervention (specifically, for phentermine non-responders, is it better to add topiramate to phentermine or switch to topiramate monotherapy). Critically, participant characteristics that may differentially affect response to treatment will be assessed and evaluated as potential moderators of intervention efficacy. CONCLUSION: Data from this study will be used to inform the development of an adaptive intervention for the treatment of adolescent severe obesity that includes empirically-derived decision rules regarding when and how to use AOM. Future research will test this adaptive intervention against standard "one-size-fits-all" treatments.

Biodegradation of selected aminophosphonates by the bacterial isolate Ochrobactrum sp. BTU1.

Aminophosphonates, like glyphosate (GS) or metal chelators such as ethylenediaminetetra(methylenephosphonic acid) (EDTMP), are released on a large scale worldwide. Here, we have characterized a bacterial strain capable of degrading synthetic aminophosphonates. The strain was isolated from LC/MS standard solution. Genome sequencing indicated that the strain belongs to the genus Ochrobactrum. Whole-genome classification using pyANI software to compute a pairwise ANI and other metrics between Brucella assemblies and Ochrobactrum contigs revealed that the bacterial strain is designated as Ochrobactrum sp. BTU1. Degradation batch tests with Ochrobactrum sp. BTU1 and the selected aminophosphonates GS, EDTMP, aminomethylphosphonic acid (AMPA), iminodi(methylene-phosphonic) (IDMP) and ethylaminobis(methylenephosphonic) acid (EABMP) showed that the strain can use all phosphonates as sole phosphorus source during phosphorus starvation. The highest growth rate was achieved with AMPA, while EDTMP and GS were least supportive for growth. Proteome analysis revealed that GS degradation is promoted by C-P lyase via the sarcosine pathway, i.e., initial cleavage at the C-P bond. We also identified C-P lyase to be responsible for degradation of EDTMP, EABMP, IDMP and AMPA. However, the identification of the metabolite ethylenediaminetri(methylenephosphonic acid) via LC/MS analysis in the test medium during EDTMP degradation indicates a different initial cleavage step as compared to GS. For EDTMP, it is evident that the initial cleavage occurs at the C-N bond. The detection of different key enzymes at regulated levels, form the bacterial proteoms during EDTMP exposure, further supports this finding. This study illustrates that widely used and structurally more complex aminophosphonates can be degraded by Ochrobactrum sp. BTU1 via the well-known degradation pathways but with different initial cleavage strategy compared to GS.

Factors contributing to whether or not people with obesity undergo bariatric surgery.

BACKGROUND: Bariatric surgery has been suggested as a safe and effective way to treat obesity by facilitating weight loss, but factors that predict the likelihood of bariatric surgery are unknown. The objective of this study was to describe factors associated with individuals with obesity that influence their decision to undergo bariatric surgery. SUBJECTS AND METHODS: The study design was a cross-sectional study and participants were recruited via a survey link posted on the Obesity Action Coalition website. Demographic data, medical data, weight loss program data, and reports of personal experiences were gathered via an online survey. A multivariate logistic regression model was conducted to examine predictors associated with bariatric surgery (N = 4192). RESULTS: Participants who took phentermine (OR=2.983), Phentermine-topiramate (Qsymia) (OR=2.863), Naltrexone-bupropion (Contrave) (OR=3.246), or Liraglutide (Saxenda) (OR=2.144) had a higher likelihood of undergoing bariatric surgery for weight loss. Participants with type 2 diabetes (OR=1.728), post-traumatic stress disorder (PTSD) (OR=1.489), or COVID-19 (OR=3.852) had a higher likelihood of undergoing bariatric surgery while sleep apnea (OR=0.760) was associated with a lower likelihood of receiving surgery. Those who used MyFitnessPal™ (OR=2.232), Noom™ (OR=1.400), Jenny Craig™ (OR=1.533), or Keto (OR=1.664) for weight loss had a higher likelihood of obtaining bariatric surgery. Personal trauma experiences of sexual abuse (OR=1.982) and physical abuse (OR=1.490) were more associated with participants who underwent surgery. CONCLUSIONS: A variety of characteristics were associated with decisions to undergo bariatric surgery. These findings may help to determine ways to support individuals who are considering bariatric surgery.

Potential drug-drug interactions with phentermine among long-term phentermine consumers: A retrospective analysis.

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.

Cost-Effectiveness of Antiobesity Drugs for Adolescents With Severe Obesity.

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.

Cost-Effectiveness of Pharmacotherapy for the Treatment of Obesity in Adolescents.

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.