BMI is used as a screening tool for obesity. An individual with a BMI of 30 or higher is considered to have obesity. Over the past two decades, both the prevalence of obesity and estimates of the medical spending associated with individuals with obesity have increased. For example, a 2018 study estimated that the percentage of national medical expenditures used to treat obesity-related illnesses in adults increased from 6.13 percent in 2001 to 7.91 percent in 2015, a 29 percent increase. This study also found that the high medical costs of obesity are due to extremely high medical costs among a small percentage of the population who have severe obesity (those with a BMI of 40 or higher). In addition, a 2017 study found that medical expenditures rise most rapidly for individuals with a BMI of 40 or higher. One option for the treatment of obesity is the use of prescription obesity drugs. As of June 2019, there were nine prescription drugs approved by FDA to treat obesity. Four obesity drugs—benzphetamine, diethylpropion, phendimetrazine, and phentermine—were approved by FDA in 1961 or earlier for short-term use, which is generally about 12 weeks, and are available as generic drugs. The remaining five obesity drugs were approved by FDA in 1999 or later for long-term use and are available as brand-name drugs— bupropion/naltrexone (Contrave), liraglutide (Saxenda), lorcaserin (Belviq), orlistat (Xenical), and phentermine/topiramate (Qsymia). Each of these five brand-name obesity drugs underwent one or more randomized, controlled clinical trials for safety and efficacy prior to FDA approval of the drug—a total of 15 clinical trials across the five drugs. Obesity drugs work in different ways; some may help an individual feel full sooner or less hungry, while others may reduce fat absorption in the body. Results vary by medication and by person, but, according to the National Institutes of Health, on average, people who take obesity drugs as part of a lifestyle program lose between 3 and 9 percent more of their starting body weight than people in a lifestyle program who do not take obesity drugs. As with other prescription drugs, obesity drugs may have side effects such as headache, dizziness, dry mouth, nausea, and diarrhea. And, as with other prescription drugs, health care providers may prescribe an obesity drug for off-label use— that is, for a different medical condition, in a different dosage, or for a different duration than for which the drug is FDA approved. Obesity drugs should be used as an adjunct to lifestyle therapy (e.g., diet, physical activity, and behavioral counseling), according to guidelines from several medical associations. According to these guidelines, the use of obesity drugs is indicated for individuals with a BMI of 27 or higher with one or more obesity comorbidities (such as type 2 diabetes), or individuals with a BMI of 30 or higher who have a history of failure to achieve clinically meaningful weight loss (that is, weight loss of 5 percent or more) or who are unable to sustain weight loss. In addition, the guidelines recommend evaluating the patient’s weight loss after about 12 to 16 weeks of treatment with an obesity drug and discontinuing the drug if the patient has not lost a certain amount (e.g., at least 5 percent) of their initial body weight. Although obesity is classified as a disease, some health care providers, including those who specialize in the care of patients with obesity, continue to stigmatize patients with obesity. For example, a 2018 study reported that health care providers may perceive patients with obesity as being less compliant and having less self-discipline than other patients. Additionally, health care providers may not initiate discussions about weight loss with patients because of lack of time, other important issues or concerns, a belief that a patient is not motivated or interested in losing weight, or concern over a patient’s emotional state, according to another 2018 study. The prevalence of obesity was about 38 percent among all U.S. adults (about four of every 10 adults) from 2013 through 2016, according to nationally representative estimates from CDC. The estimate of prevalence among adults covered by Medicare was about 40 percent, and among those with Medicaid or other public health insurance (excluding Medicare) it was about 42 percent. In addition, the prevalence of obesity among adults with private health insurance coverage and among the uninsured was similar, at about 37 percent and 38 percent, respectively. These national estimates also showed that about 24 percent of Medicare beneficiaries had Class 1 obesity, about 10 percent had Class 2 obesity, and about 6 percent had Class 3, or severe, obesity. (See fig. 1.) According to CDC estimates, adults age 18 to 64 and adults age 65 and older had a similar prevalence of obesity, about 39 percent and 38 percent, respectively. However, a higher percentage of adults age 18 to 64 than adults age 65 and older had Class 3 obesity. (See table 1.) Appendix III provides additional information on the prevalence of obesity among adults, as well as on the prevalence of adults who were overweight, which is defined as a BMI of 25 to <30, including 95 percent confidence intervals. Relatively few U.S. adults, including adults with obesity and adults who reported trying to lose weight, used obesity drugs from 2012 through 2016, according to nationally representative estimates. Guidelines suggest prescribing obesity drugs as an adjunct to other diet and lifestyle changes, or when other approaches have not resulted in clinically significant weight loss. Those health care providers who prescribe obesity drugs consider several factors, such as whether there are any contraindications of the obesity drug for their patients and the cost of the drug. Some limited data are available on individuals who have used obesity drugs, including data on whether these individuals adhered to taking the prescribed obesity drug or maintained their weight loss over time. Available data indicate that relatively few U.S. adults, including those with obesity, used obesity drugs. Specifically, of the estimated 233 million U.S. adults, fewer than a million used any of the nine obesity drugs, according to AHRQ’s nationally representative estimates from MEPS data for 2012 through 2016. Of the estimated 71.6 million U.S. adults with obesity, an estimated 660,000 per year, on average, used an obesity drug, according to these data. Similarly, among those who reported trying to lose weight, relatively few of them (about 3 percent) reported that they took prescription medication for weight loss, according to CDC’s nationally representative estimates from NHANES for 2013 through 2016. Additionally, six of the studies we reviewed examined this topic and found that few U.S. adults have used obesity drugs. For example, one study reported that in 2011, 2,554 obesity drug prescriptions were filled per 100,000 people, with about 87 percent of those prescriptions for phentermine, a generic obesity drug. Three other studies assessed the use of obesity drugs among veterans receiving care from the Veterans Health Administration and similarly found that few patients were prescribed obesity drugs. One of these studies found that about 1 percent of the 153,939 veterans who enrolled in the MOVE! Weight Management Program from 2013 through 2016 were prescribed an obesity drug (orlistat, phentermine, phentermine/topiramate, liraglutide, or bupropion/naltrexone) within 1 year of MOVE! initiation. According to officials from groups representing physicians and advocacy groups we interviewed, and seven studies we reviewed, some physicians and other health care providers may not be open to or comfortable with prescribing obesity drugs. For example, providers may not perceive obesity drugs to be safe or effective. According to officials from one advocacy and research group, concerns about the safety of obesity drugs may be related to the adverse consequences associated with past obesity drugs. In addition, one medical association we contacted indicated physicians consider clinical preventive service recommendations from the U.S. Preventive Services Task Force on the use of obesity drugs. The task force recommends that clinicians offer or refer adults with a BMI of 30 or higher to intensive, multicomponent behavioral interventions. Further, a systematic review of evidence of the benefits and harms of behavioral therapy and use of obesity drugs conducted for the task force found that obesity drugs, but not behavior-based interventions, were associated with higher rates of harm. The potential for harm (i.e., adverse events) may discourage physicians and other health care providers from prescribing these drugs. In addition, officials we interviewed and the studies we reviewed noted that a lack of insurance coverage, high out-of-pocket costs, and the patient’s means to afford obesity drugs may also discourage physicians from prescribing obesity drugs. The officials and studies also noted that physicians might have gaps in knowledge about obesity drugs. For example, officials from one medical association noted that lack of education is a barrier to physicians in prescribing obesity drugs for patients who would be candidates for them, and officials from another medical association said that many clinicians are not aware that there are FDA-approved drugs for obesity, and therefore they do not think about prescribing them. One study we reviewed found that, of the 111 primary care providers responding to a survey, most reported limited experience with obesity drugs as a barrier to prescribing them. While guidelines on the use of obesity drugs suggest prescribing obesity drugs as an adjunct to other diet and lifestyle changes, or when other approaches have not resulted in clinically significant weight loss, physicians and other health care providers may not understand the recommendations outlined in the guidelines. For example, one study found that many of the health care providers responding to a survey reported responses inconsistent with the guideline-recommended thresholds to initiate and continue use of obesity drugs. Physicians and health care providers who do prescribe obesity drugs take several factors into consideration. Specifically, before prescribing an obesity drug, these providers consider the likely benefits of weight loss, the drug’s possible side effects, the patient’s current health issues and other medications, family medical history, and the cost of the drug, according to the National Institutes of Health. According to officials from an advocacy group, specific considerations include (1) the patient’s other health conditions that may increase the risk from using a particular obesity drug (contraindications); (2) the ability of an obesity drug to treat both the patient’s obesity and other health conditions; (3) the patient’s ability to afford a particular obesity drug, given their insurance coverage and other financial resources; (4) patient preference regarding the dosage and form of the drug; and (5) the average efficacy (weight loss) of an obesity drug. Further, when treating obesity, providers use the least invasive treatments, such as lifestyle-based therapies first, then escalate to obesity drugs if noninvasive treatments prove ineffective, according to officials from the same advocacy group. Some limited data are available on individuals who have used obesity drugs, including data on the distribution of BMI, the use of obesity drugs in conjunction with other items or services, whether these individuals adhered to using the prescribed obesity drug or maintained their weight loss over time, and the impact that using obesity drugs has on other medical services directly related to obesity. The following is a summary of available information on specific aspects of individuals who have used obesity drugs. Distribution of BMI across individuals who have used obesity drugs. CDC’s nationally representative estimates for 2013 through 2016 found that the BMI of adults who reported that they used obesity drugs ranged from 21 to 64, with a median BMI of 34. However, these data are limited because they do not indicate how long the individual used the drugs before their BMI was measured. Use of obesity drugs in conjunction with other items or services. Two studies we reviewed examined the use of obesity drugs in conjunction with other items or services. These studies found that participants who used an obesity drug in conjunction with other services, such as behavioral counseling, lost more weight than those who did not take the drug with the other services. For example, in one 2019 study, participants who received intensive behavioral therapy combined with an obesity drug, liraglutide, had nearly double the weight loss (an average of about 12 percent of their body weight) compared to the participants who received only intensive behavioral therapy (an average of about 6 percent of their body weight). In addition, the 15 clinical trials for the brand-name obesity drugs that we reviewed generally found that a significantly higher percentage of participants who used the obesity drug combined with other items or services (such as a low-calorie diet or increased physical activity) achieved 5 percent or more weight loss compared to participants who used a placebo with the other items or services. One clinical trial that used an intensive behavior modification program (28 group sessions) found higher average weight loss (9 percent loss of initial body weight) for participants who used the obesity drug (bupropion/naltrexone) than for the placebo group. This clinical trial also found that the placebo group with the intensive behavior modification had higher weight loss than placebo groups in the other clinical trials, none of which used intensive behavioral therapy. Adherence to using the prescribed obesity drug. FDA’s analysis of Sentinel System data of obesity drugs dispensed in 2008 through 2017 found that in the majority of patients using obesity drugs, cumulative treatment duration was 90 days or less. FDA analyzed data for 267,836 new users of obesity drugs and found that about 58 percent of patients who used any of the obesity drugs did so for 90 days or less; about 31 percent used any of the obesity drugs for 30 or fewer days. The average duration for the first use of any of the nine obesity drugs was 69 days. (See appendix V for more data from FDA’s analysis.) FDA’s findings are consistent with the findings of two of the three studies that we reviewed that measured adherence to using the prescribed obesity drug. These studies reported that use of obesity drugs dropped significantly after 30 days. For example, one 2018 study that reviewed 1 year of data on 26,522 patients who had new prescription drug claims for one of four obesity drugs (liraglutide, lorcaserin, bupropion/naltrexone, and phentermine/topiramate) found that adherence to using any of the four obesity drugs dropped markedly during the first month following the initial claim for the drug. In addition, while the 15 clinical trials we reviewed were not designed to measure adherence to taking obesity drugs, they provide some information on whether or not study participants adhered to using these drugs during the trials. Participant dropout rates for these clinical trials ranged from 14 percent to 66 percent for the obesity drug treatment and the placebo groups, which could indicate difficulty in adherence to the study regimen; however, participants using the placebo generally had higher dropout rates than those using the obesity drug. The reasons for discontinuation among study participants in the clinical trials included side effects, such as headaches and nausea; being unavailable for follow up; and withdrawal of consent. Maintaining weight loss over time by individuals who have used obesity drugs. The recent systematic review conducted for the U.S. Preventive Services Task Force noted that data on long-term weight loss with obesity drugs are limited. The review found that individuals using obesity drugs were more likely to maintain their weight loss over 12 to 36 months compared with placebo, but noted that the evidence was limited by the small number of trials for each medication, poor follow up with participants, and limited applicability (given that participants had to meet narrowly defined inclusion criteria), among other limitations. We also identified six studies—each of which reviewed one of the FDA-approved obesity drugs—that examined weight loss maintenance, generally after about 1 year. For example, a 2018 study for one obesity drug (lorcaserin) found that while the obesity drug initially improved upon weight loss achieved with weight loss maintenance counseling, this advantage was not maintained at 1 year. That is, after 1 year, there was no significant difference in weight loss maintenance between the participants treated with the obesity drug along with counseling, compared to those treated with placebo along with counseling. Another study that examined clinical trial data for one obesity drug (bupropion/naltrexone) concluded that participants who lost at least 5 percent of their body weight after 16 weeks were likely to maintain clinically significant weight loss (of at least 5 percent) after 1 year of treatment with the drug. The impact of using obesity drugs on medical services directly related to obesity. We did not identify any studies on the impact that the use of obesity drugs had on the utilization of medical services directly related to obesity. In terms of studies on the impact on health outcomes, the systematic review conducted for the U.S. Preventive Services Task Force concluded that health outcomes data for individuals receiving treatment with obesity drugs were limited. The review reported that clinical trials of obesity drugs for weight loss examined few outcomes beyond quality of life measures, and that none of the drug-based maintenance trials reported the effects of the obesity drug interventions on health outcomes. The review noted that the trials included in the review were of highly selected populations with multiple exclusions relevant to health outcomes (e.g., history of serious medical conditions). The review further noted that while it appears that weight loss interventions, including obesity drugs, can reduce diabetes incidence, larger studies with longer-term follow up are required to understand the full benefits of these interventions on health outcomes and whether those effects are long lasting. Health insurance coverage for obesity drugs is limited—that is, not all public and private health insurance provided coverage for obesity drugs or may have additional requirements to determine these drugs are medically necessary. Medicare Part D plans may opt to cover obesity drugs, and state Medicaid programs or Medicaid managed care plans within states may choose either to cover or exclude obesity drugs from coverage. We found that both Medicare Part D and Medicaid reimbursed for a relatively small number of prescriptions for obesity drugs in 2016 and 2017. For private health insurance—which includes employer- sponsored health insurance, individually purchased health plans, and FEHBP plans—we found that coverage varied and, when obesity drugs were covered, the coverage could have additional requirements such as prior authorization or determination that a drug is medically necessary for the patient. Medicare. Under Medicare’s prescription drug benefit, Medicare Part D plans may choose to cover obesity drugs—in these cases, obesity drugs are considered supplemental drugs under an enhanced alternative coverage plan. Medicare beneficiaries who select a Part D plan that offers supplemental benefits, which may include coverage of excluded drugs such as obesity drugs, must pay the full premium cost for those additional benefits (i.e., Medicare does not subsidize them). Medicare Part D plans can choose whether or not to offer enhanced alternative coverage, and not all Medicare Part D plans that provide enhanced alternative coverage cover obesity drugs as supplemental drugs. For example: Roughly half of the Medicare beneficiaries covered by one large insurer’s Medicare Part D plans in one state have coverage for obesity drugs as a supplemental drug under enhanced alternative coverage, according to officials from that insurer. Officials at another large insurer told us that their Medicare Part D plans have historically covered supplemental drugs based on consumer demand, and obesity drugs do not typically meet their threshold for offering supplemental coverage. The officials noted that their plans have limited funds to cover supplemental drugs and that consumer demand is typically highest for other types of drugs, such as drugs to treat erectile dysfunction. Enhanced Alternative Coverage and Supplemental Drugs under Medicare Enhanced alternative coverage is alternative prescription drug coverage under Medicare Part D with value exceeding that of Medicare Part D’s defined standard coverage. Enhanced alternative coverage may include basic prescription coverage and supplemental benefits such as supplemental drugs. Supplemental drugs are drugs—including drugs for weight loss—that would be covered Part D drugs but for the fact that they are specifically excluded as Part D drugs under Medicare Part D’s basic prescription drug coverage. Medicare Part D plans may offer these excluded drugs, such as obesity drugs, as a supplemental drug under enhanced alternative coverage. A Medicare Part D plan can choose which drugs it covers as a supplemental drug under enhanced alternative coverage—that is, not all plans cover the same supplemental drugs as part of enhanced alternative coverage. Data from CMS on Medicare Part D reimbursement for obesity drugs provide some insight on coverage. For example, our analysis found that in 2017, 27 Medicare Part D plans reimbursed for obesity drugs under enhanced alternative coverage for 209 Medicare beneficiaries. (See table 2 for 2016 and 2017 data.) See appendix VI for more information. Medicaid. State Medicaid programs or Medicaid managed care plans within states may choose either to cover or exclude obesity drugs from coverage. Our analysis found that in 2017, Medicaid programs or Medicaid managed care plans in 41 states reimbursed pharmacies and other providers for at least one claim for an obesity drug, for a total of 30,800 prescriptions. (See table 3 for 2016 and 2017 data.) Medicaid managed care organizations may provide coverage of obesity drugs not covered by the state plan, according to CMS. See appendix VII for more information. Employer-sponsored and individually purchased health plans. Coverage of the nine obesity drugs varied in employer-sponsored and individually purchased health plans, according to the insurers and pharmacy benefit managers we interviewed. For example: Officials from one large insurer told us that coverage of obesity drugs is included in plans for about 90 percent of their members; only a small percentage of members do not have plans with this coverage. Officials from another large insurer surveyed its health plans in different geographic locations and found that, of those that responded, four of the six employer-sponsored and three of the six individually purchased health plans covered the nine obesity drugs. They said that many of the plans that covered obesity drugs in their employer- sponsored markets also covered these drugs in their individual market. Officials at a large pharmacy benefit manager said employers that provide employer-sponsored health insurance can choose to customize their formulary and decide whether to include obesity drugs. They said their select and premium prescription drug formularies include obesity drugs, so companies that decide to offer those formularies would cover obesity drugs, but many companies choose to customize their formularies and may not include obesity drugs. Even if employer-sponsored and individually purchased health plans offer coverage of obesity drugs, these plans often put requirements in place to determine a beneficiary’s eligibility for coverage of obesity drugs, according to officials from insurers and pharmacy benefit managers we interviewed. For example, plans may require beneficiaries to obtain prior authorization, require a determination of medical necessity of the drug for the patient, and review the drug’s effectiveness prior to making a coverage decision. For example, an official from one large insurer told us their drug formulary does not include obesity drugs because the clinical evidence indicates that other therapies are more effective for weight loss. However, this official also said that some of its plans would cover obesity drugs as a nonformulary option if a physician or other health care provider indicates that the obesity drug is medically necessary (e.g., after a patient has tried other treatment options, such as behavioral therapy). Further, if a patient is offered coverage of an obesity drug but fails to receive a clinical benefit within a specified time frame, insurers and pharmacy benefit managers told us the following: A patient and his or her physician may decide together whether the patient should continue or discontinue the obesity drug, and plans often defer to physicians to determine whether an obesity drug is medically necessary for a patient. Some plans may require additional information from a patient’s physician every 6 to 12 months for reapproval of coverage of an obesity drug, such as reporting outcomes (e.g., weight loss) while using the drug. Plans could require prior authorization to continue using an obesity drug. An individual may be able to try a different obesity drug covered by the formulary. For the largest employer-sponsored health care program in the United States—FEHBP, managed by the Office of Personnel Management—we found that some FEHBP plans offered by large insurers excluded obesity drugs from coverage. We examined the formularies for 12 plans offered by three large FEHBP insurers and found that the formularies for two plans from one insurer indicated some type of coverage of obesity drugs in 2018. One plan offered coverage for 50 percent of the plan’s allowed amount for weight management drugs, and the other plan offered coverage of two obesity drugs as tier 2 drugs, which have higher copayments than tier 1 drugs. For individually purchased health plans offered on health care exchanges, nine of the 34 states with federally facilitated exchanges had at least one plan in the silver tier of coverage that included some type of coverage for obesity drugs in 2018, according to a 2018 study. The study found that covered obesity drugs were generally the older drugs and that the newer drugs tended to be covered with higher copayments or more likely to require prior authorizations than other medications. Out-of-pocket payments from the patient or patient’s family made up two- thirds of the amounts paid for obesity drugs, according to nationally representative estimates for 2012 through 2016. These amounts could include insurance copayments and deductible amounts, and payments for obesity drugs not covered by insurance. Private health insurance paid about one quarter of the amount paid for obesity drugs, and Medicare and other public health insurance paid the remainder. Average annual medical spending and prescription drug spending were higher for adults who used any of the nine obesity drugs than for those who did not, according to these estimates. However, the differences in these estimates do not establish any causal relationship between using obesity drugs and having higher average annual medical or prescription drug spending. Out-of-pocket payments made up about two-thirds of total amounts paid for obesity drugs for U.S. adults and private health insurance paid a quarter, according to AHRQ’s nationally representative estimates from MEPS data for 2012 through 2016. Medicare, Medicaid, and other public health insurance paid the remainder; however, estimates for each of these sources of payment are imprecise. (See fig. 2.) Similar to studies on the use of obesity drugs, AHRQ’s estimates also found that 80 percent of amounts paid for any of the nine obesity drugs was for one obesity drug, phentermine, which is available as a generic drug. We also examined available spending data from CMS on payments for obesity drugs and found the following: Medicare Part D prescription drug plans spent $19,714 for obesity drugs in 2016 and $140,296 in 2017, according to our analysis of CMS’s Prescription Drug Event data. These amounts include Medicare Part D plan reimbursements for any of the nine obesity drugs under enhanced alternative coverage. CMS’s data also showed that total beneficiary spending—that is, the total amount Medicare beneficiaries paid out of pocket as copayments or deductibles—for any of these prescriptions totaled $4,048 in 2016 and $5,376 in 2017. See appendix VI for more information. Total Medicaid state and federal spending—that is, reimbursement amounts for the nine obesity drugs—was at least $5,017,424 in 2016 and $7,453,442 in 2017, according to our analysis of available data from CMS’s Medicaid State Drug Utilization data. These amounts do not include all Medicaid spending for obesity drugs under Medicaid managed care. For example, if a Medicaid program pays a managed care organization for drugs as part of their capitated payment for all Medicaid services, they are not reimbursed on a per-drug basis, and obesity drugs covered by Medicaid in that state would show up as a $0 reimbursement amount in CMS’s Medicaid State Drug Utilization data. According to CMS data, Medicaid spending for obesity drugs was the greatest in California in 2016 and 2017. See appendix VII for more information. In addition, when the number of prescriptions dispensed are counted, FDA’s estimates from 2017 IQVIATM data—which are projected nationally from prescriptions dispensed in about 59,900 outpatient retail pharmacies—found that most prescriptions dispensed for obesity drugs were paid for by private insurance. FDA’s analysis found that almost 64 percent of prescriptions dispensed for any of the nine obesity drugs was paid for by private health insurance, and 35 percent of prescriptions dispensed was paid for by cash (i.e., out-of-pocket) payments paid for by the patient or their family in 2017. The remaining 1 percent of prescriptions dispensed for obesity drugs was paid for by Medicare Part D and Medicaid at an estimated 0.9 percent and 0.1 percent, respectively. For all U.S. adults age 18 to 64, the estimated average annual medical and prescription drug spending per adult was higher for those who used an obesity drug than for those who did not use an obesity drug. Specifically, the estimated average annual medical expenditures were $7,575 per adult who used an obesity drug and $4,302 for those who did not, according to AHRQ’s nationally representative estimates from MEPS data for 2012 through 2016. Further, the estimated average annual prescription drug expenditures per adult were $2,198 for those who used an obesity drug and $1,111 for those who did not. However, these data do not necessarily indicate that use of obesity drugs leads to higher average annual medical and prescription drug spending. For U.S. adults with obesity, there was not a significant difference between the estimated average annual medical and prescription drug expenditures per adult for those who used an obesity drug and those who did not use an obesity drug. This may be due to the small sample size of 279 adults with obesity who used an obesity drug in the MEPS data. Appendix VIII provides more information on AHRQ’s estimated expenditures for obesity drugs and other medical and prescription drug spending. We did not identify any studies other than AHRQ’s estimates from MEPS data that specifically addressed the medical spending for adults who used obesity drugs compared to those who did not. We provided a draft of this report to HHS for review and comment. HHS provided technical comments, which we incorporated as appropriate. We are sending copies of this report to the Secretary of Health and Human Services, appropriate congressional committees, and other interested parties. In addition, the report will be available at no charge on the GAO Web site at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (202) 512-7114 or dickenj@gao.gov. Contact points for our Offices of Congressional Relations and Public Affairs are on the last page of this report. GAO staff who made major contributions to this report are listed in appendix IX. The Bipartisan Budget Act of 2018 included a provision for GAO to review the prevalence of obesity and the use of obesity drugs in the Medicare and non-Medicare populations, including spending for and coverage of these drugs. We examined (1) the prevalence of obesity among adults in the United States; (2) what is known about the use of obesity drugs and the individuals who use them; (3) what is known about health insurance coverage of obesity drugs; and (4) what is known about spending on obesity drugs and about medical spending for adults who used obesity drugs compared to those who did not. To address our reporting objectives, we examined estimates from federal agencies within the Department of Health and Human Services (HHS), including the Centers for Disease Control and Prevention’s (CDC) estimates from the National Health and Nutrition Examination Survey (NHANES), the Agency for Health Care Research and Quality’s (AHRQ) estimates from the Medical Expenditure Panel Survey (MEPS), and the Food and Drug Administration’s (FDA) estimates from IQVIA and the Sentinel System. We also analyzed Medicare Part D Prescription Drug Event data and Medicaid State Drug Utilization data from the Centers for Medicare & Medicaid Services (CMS). For each data source, we examined the latest available data at the time of our review. In addition, we conducted a literature review; interviewed officials and reviewed documents from stakeholder organizations, federal agencies, insurers, and others; and examined relevant laws and regulations. We examined CDC’s nationally representative estimates from NHANES of the prevalence of obesity among U.S. adults and use of obesity drugs. NHANES is a cross-sectional survey designed to monitor the health and nutritional status of the civilian, noninstitutionalized U.S. population. The survey consists of interviews conducted in participants’ homes and standardized physical examinations, including measured height and weight, conducted in mobile examination centers. CDC analyzed data from two 2-year cycles of NHANES (2013 through 2014 and 2015 through 2016) for the prevalence of obesity [defined as a body mass index (BMI) of 30 or higher] for all adults by age (18 and older, 18 through 64, and 65 and older), health insurance coverage, and class of obesity. The insurance categories were mutually exclusive: (1) Medicare, which includes all adults who reported having Medicare, regardless of whether they reporting having another type of health insurance (e.g., private health insurance) in addition to Medicare; (2) private health insurance (excluding individuals with Medicare); (3) Medicaid/public health insurance (excluding Medicare); and (4) uninsured. We also examined CDC’s estimates from NHANES on the prevalence of overweight (defined as a BMI of 25 to <30) among U.S. adults. In addition, we examined CDC’s estimates from NHANES for 2013 through 2016 on adults who took prescription medications for weight loss. NHANES asks participants if they tried to lose weight, and, for those who did, if they took diet pills prescribed by a doctor. CDC’s estimates included the lower and upper bounds of the 95 percent confidence intervals (the interval that would contain the actual population value for 95 percent of the samples NHANES could have drawn). We examined AHRQ’s nationally representative estimates from MEPS data on the use of and payment sources for obesity drugs. MEPS collects nationally representative data on health care use, expenditures, sources of payment, and insurance coverage for the U.S. civilian, noninstitutionalized population. For this analysis, AHRQ estimated the distribution of payments for obesity drugs using MEPS pooled data for years 2012 through 2016. We also examined AHRQ’s estimates from MEPS of annual expenditures for medical care and all prescription drugs—for those individuals who used obesity drugs and those who did not—and annual expenditures for obesity drugs. AHRQ’s estimates included the lower and upper bounds of the 95 percent confidence intervals. We examined FDA’s nationally projected data on the prescriptions dispensed for obesity drugs from outpatient retail pharmacies using 2017 IQVIA™ National Prescription Audit Extended Insights and IQVIA™ Total Patient Tracker. IQVIA™ is proprietary data that includes data for prescriptions dispensed at approximately 59,900 U.S. outpatient retail pharmacies. FDA analyzed IQVIA data and provided aggregated results for the nationally estimated number of prescriptions dispensed for the nine obesity drugs from U.S. outpatient retail pharmacies, by payment method. These patterns may not apply to other settings of care (e.g., mail-order or specialty pharmacies or clinics). In addition, the analysis captures data when a prescription was dispensed; it does not indicate that the patient took the obesity drug, and it does not indicate if the drug was prescribed off label for something other than weight loss. We examined FDA’s national estimates of prescriptions for obesity drugs dispensed by outpatient pharmacies for new users of obesity drugs (by number of days supplied and by age and gender of patient) from the agency’s Sentinel System. FDA’s Sentinel System uses prescription drug dispensing data from populations with federal or commercial insurance to characterize drug utilization of a large U.S. population with private and public health insurance. FDA examined drug dispensing data from January 1, 2008, through December 31, 2017, from 17 of 18 Sentinel data partners, including Medicare, which contributed fee-for- service enrollee data. FDA analyzed dispensings for 267,836 new users of the nine prescription obesity drugs. FDA estimated the duration of the first treatment episode (in days) for patients’ prescription dispensings for any of the nine obesity drugs using a 14-day episode gap—that is, if there were more than 14 days between exhausting the previous dispensing’s days supplied for that prescription and refilling the prescription, then FDA counted it as a new treatment episode. FDA estimated cumulative treatment duration by summing days’ supply of all dispensings of an obesity drug during a patient’s presence in the database, without regard to time between dispensings. For information on the number of claims for obesity drugs that were reimbursed, the number of plans that provided reimbursement, and the amount reimbursed for obesity drugs under the Medicare prescription drug program known as Medicare Part D, we analyzed Medicare Prescription Drug Event data from CMS for 2016 and 2017. We analyzed Medicare Part D plan reimbursements (payments to pharmacies) and beneficiary spending (the total amount Medicare beneficiaries paid out of pocket as copayments or deductibles) for the nine obesity drugs for claims that CMS’s data coded as reimbursed as a supplemental drug under enhanced alternative coverage. We excluded 1,787 claims in 2016 and 1,775 claims in 2017 for one obesity drug, orlistat (Xenical), that were listed in CMS’s data as covered under Medicare Part D (and were not coded as a supplemental drug under enhanced alternative coverage). According to CMS officials, orlistat has off-label indications including diabetes and hyperlipidemia, and when orlistat is used for these indications the drug would be covered under Medicare Part D, and the Medicare Part D plan is responsible for ensuring it is dispensed appropriately per Medicare Part D policy. We also excluded 25 claims in 2016 and 26 claims in 2017 for prescription obesity drugs listed as over-the-counter in the prescription drug event data because, according to CMS, these appear to be outliers. Because our analysis was limited to those instances in which a Medicare Part D plan reimbursed for an obesity drug as a supplemental drug under enhanced alternative coverage, the number of Medicare Part D plans that provided coverage for obesity drugs could be higher. For example, some plans may have covered obesity drugs, but none of the beneficiaries enrolled in these plans filled a prescription for such a drug. For information on obesity drugs reimbursed by state Medicaid programs or Medicaid managed care programs within those states, we analyzed CMS’s Medicaid State Drug Utilization data for 2016 and 2017. We analyzed the data to estimate the number of prescriptions reimbursed and total Medicaid state and federal spending—that is, the Medicaid amount reimbursed (state and federal reimbursement, including dispensing fees)—for the nine obesity drugs. These amounts do not include all Medicaid spending for obesity drugs because managed care organizations can be paid for the drugs as part of their capitated payment for all Medicaid services, they are not reimbursed on a per-drug basis, and their payments are not recorded in CMS’s Medicaid State Drug Utilization data. Because our analysis was limited to those instances in which Medicaid reimbursed for an obesity drug, the number of states in which state Medicaid programs or Medicaid managed care plans provided coverage for obesity drugs could be higher. For example, a state could have provided coverage for obesity drugs, but no beneficiaries in that state filled a prescription for an obesity drug. We obtained information and reviewed studies from officials from eight stakeholder organizations (representing medical associations and advocacy groups for obesity research and treatment) on the use of obesity drugs and guidelines for using obesity drugs and to obtain their perspectives on what physicians and other health care providers take into consideration when prescribing these drugs, among other things. These stakeholders were selected because of their medical or scientific expertise, relevant publications, or familiarity with the treatment of obesity and obesity drugs. We also reviewed data and documents and interviewed officials from HHS agencies: CDC, FDA, AHRQ, CMS, and the National Institutes of Health. In addition, we reviewed guidance documents and obtained information from the Office of Personnel Management, which administers the Federal Employees Health Benefits program (FEHBP). FEHBP is the largest employer-sponsored health insurance program in the United States, providing health insurance coverage to about 8 million federal employees, retirees, and their dependents in 2016 through contracts with private health insurance plans. We obtained information about the health insurance coverage of obesity drugs from officials from the three largest pharmacy benefit managers, four large insurers, and two organizations knowledgeable about prescription drug benefits for employer-sponsored health plans. We also reviewed drug formularies for selected private health insurance plans, including FEHBP plans, to determine if any of the nine obesity drugs were included. We conducted a literature review of relevant peer-reviewed studies published from January 2012 through January 2019. We identified studies through a search of bibliographic databases, including ProQuest, Scopus, MEDLINE, and International Pharmaceutical Abstracts , using terms such as “obesity,” “weight loss,” and “prescriptions.” Of the 765 citations we identified, we reviewed 220 full studies, which we examined for information related to the use of obesity drugs and individuals who use them, coverage of obesity drugs, and spending for obesity drugs for individuals who used them compared to those who did not. We determined 19 studies were relevant to the use of obesity drugs and 1 study was relevant to coverage of obesity drugs. Our literature review focused on studies with a U.S.-based, adult population (age 18 and older); we excluded studies related to childhood obesity and studies on animals. We also examined available information on the clinical trials conducted prior to FDA approval of the prescription obesity drugs for the U.S. market, including 64 studies from our literature review that summarized one or more of the clinical trials. We also identified 17 additional studies in our literature review that provided relevant background information. Additionally, we reviewed five studies provided by stakeholder organizations (in addition to the studies we had identified in our literature review) that we determined were relevant to our research objectives, as well as guidelines for the use of obesity drugs in obesity treatment. To determine the reliability of the data we used for all four objectives— CDC’s estimates from NHANES, AHRQ’s estimates from MEPS, FDA’s data from IQVIA and the Sentinel System, and CMS’s Medicare Part D Prescription Drug Event data and Medicaid State Drug Utilization data— we reviewed documentation on data collection processes and discussed limitations of the data with the relevant federal agency officials. In addition, we conducted data reliability checks on the data, when appropriate. We determined the data used in this report were sufficiently reliable for our purposes. We conducted this performance audit from April 2018 to August 2019 in accordance with generally accepted government auditing standards. Those standards require that we plan and perform the audit to obtain sufficient, appropriate evidence to provide a reasonable basis for our findings and conclusions based on our audit objectives. We believe that the evidence obtained provides a reasonable basis for our findings and conclusions based on our audit objectives. Table 4 provides additional information on the nine prescription drugs approved by the Food and Drug Administration (FDA) to treat obesity that we included in our review. This appendix presents national estimates of the prevalence of obesity among U.S. adults age 18 and older, based on the Centers for Disease Control and Prevention’s (CDC) estimates from the National Health and Nutrition Examination Survey (NHANES) for 2013 through 2016. It presents the estimates and the ranges for the 95 percent confidence intervals for prevalence of obesity by age and class of obesity (see table 5), and by insurance coverage and class of obesity (see table 6). It also presents national estimates of the prevalence of overweight (defined as a body mass index of 25 to <30) among U.S. adults, by age and insurance coverage (see table 7). Table 8 is a list of selected studies, categorized by specific topic area, that we reviewed that pertain to our research objectives, including information related to the use of obesity drugs and individuals who use them, physician considerations in prescribing obesity drugs, and health insurance coverage of obesity drugs. We identified these studies either through our literature review of peer-reviewed studies published from January 2012 through January 2019 or from one of the stakeholder organizations we contacted. This appendix presents estimates of prescriptions dispensed for new adult users of obesity drugs by duration of use and by age and gender, using data from the Food and Drug Administration’s (FDA) Sentinel System from 2008 through 2017. Of the 267,836 new users of obesity drugs included in this analysis, the first treatment episode did not exceed 30 days in about 54 percent of patients and exceeded 90 days in about 22 percent of patients. Cumulatively, about 42 percent of patients who used any of the obesity drugs did so for more than 90 days across treatment episodes. (See table 9.) Overall, most new users of obesity drugs were female (82.2 percent) and under age 65 (91.7 percent). (See table 10.) Phentermine and bupropion/naltrexone (Contrave) were the most commonly used obesity drugs in FDA’s Sentinel System analysis. This appendix presents information on Medicare Part D plan reimbursement for obesity drugs under enhanced alternative coverage from our analysis of Centers for Medicare & Medicaid Services’ (CMS) Prescription Drug Event data. Medicare Part D plans can choose whether or not to offer enhanced alternative coverage, and not all Medicare Part D plans that provide enhanced alternative coverage cover obesity drugs as supplemental drugs. As of February 2017, 1,949 Medicare Part D plans provided enhanced alternative coverage to 18.9 million Medicare beneficiaries, according to the Medicare Payment Advisory Commission. Additionally, in 2015, total Medicare Part D spending for prescription drugs was about $137 billion—this represents payments from all payers including beneficiaries (cost sharing), and excluding rebates and discounts from pharmacies and manufacturers that are not reflected in prices at the pharmacies. Tables 11 and 12 show the number of claims reimbursed, the number of plans that provided reimbursement, and the amount reimbursed for obesity drugs under Medicare Part D enhanced alternative coverage for 2016 and 2017, respectively. This appendix presents information on Medicaid reimbursements for obesity drugs under state Medicaid programs or Medicaid managed care programs within those states from our analysis of Centers for Medicare & Medicaid Services’ (CMS) Medicaid State Drug Utilization data. State Medicaid programs or Medicaid managed care programs reimbursed for at least one obesity drug prescription in 42 states in 2016 and 41 states in 2017. The amount that Medicaid reimbursed and the total number of prescriptions for obesity drugs reimbursed by Medicaid in 2016 and 2017 are shown by state (tables 13 and 14), and by obesity drug (tables 15 and 16). Over half of the prescriptions for obesity drugs reimbursed under Medicaid in 2016 and 2017 were for the generic obesity drug, phentermine. This appendix presents nationally representative estimates of U.S. adults’ average annual expenditures (spending) for medical care, all prescription drugs, and for obesity drugs from the Agency for Healthcare Research and Quality (AHRQ) based on data from the Medical Expenditure Panel Survey (MEPS) for 2012 through 2016. Table 17 shows the estimated average annual expenditures for all prescription drugs and table 18 shows the estimated average annual medical expenditures, including prescription drugs, per adult who used and per adult who did not use any obesity drugs. For adults age 18 to 64, the differences in the estimated average annual expenditures for all medical care and for all prescriptions drugs per adult who used and who did not use any of the nine obesity drugs in our review were statistically significant. However, the differences in these estimates do not indicate that there was a causal relationship between using obesity drugs and having higher average annual medical or prescription drug expenditures. Table 19 shows the estimated average annual expenditures per adult for obesity drugs. In addition to the contact above, Kim Yamane (Assistant Director), Lisa A. Lusk (Analyst-in-Charge), George Bogart, Zhi Boon, Kaitlin Dunn, Laurie Pachter, and Merrile Sing made key contributions to this report. Also contributing to this report were Alexander Cattran, Leia Dickerson, Diona Martyn, Christina Ritchie, and Ethiene Salgado-Rodriguez.

Summary: Obesity has been associated with an increased risk of developing conditions such as heart disease, stroke, diabetes, and certain types of cancer. Treatment options for individuals with obesity include lifestyle therapy, such as diet, exercise, and behavioral counseling; obesity drugs; surgery; or a combination of these efforts. The Bipartisan Budget Act of 2018 (P.L. 115-123) included a provision for GAO to review the prevalence of obesity and the use and insurance coverage of obesity drugs. This report examines the prevalence of obesity in the United States, and what is known about the use and health insurance coverage of obesity drugs, among other objectives. GAO examined data from agencies within the Department of Health and Human Services (HHS) on the prevalence of obesity (using estimates for 2013 through 2016) and the use, spending, and coverage of obesity drugs; conducted a literature review of relevant studies published from January 2012 through January 2019 in peer-reviewed and other publications; reviewed drug formularies for selected health plans; and reviewed documents and interviewed officials from federal agencies and stakeholder organizations (including medical associations, advocacy groups, pharmacy benefit managers, and insurers). HHS provided technical comments on a draft of this report, which were incorporated as appropriate. The prevalence of obesity—that is, body weight higher than what is considered a healthy weight for a given height—was about 38 percent among all U.S. adults, according to the latest available national estimates at the time of GAO's analysis. This prevalence was similar for adults with different types of health insurance. Treatment for adults with obesity may include one or more of nine prescription drugs that the Food and Drug Administration has approved for weight management (i.e., obesity drugs), though relatively few adults have used these drugs. Of an estimated 71.6 million U.S. adults with obesity, an estimated 660,000 per year, on average, used an obesity drug from 2012 through 2016, according to national estimates. Among adults who reported trying to lose weight, about 3 percent reported that they took prescription medication for weight loss from 2013 through 2016, according to national estimates. Coverage of obesity drugs varied across different types of health insurance, including Medicare and Medicaid. Plans cited factors such as low consumer demand and strong evidence supporting other treatments in their coverage decisions. GAO's analysis of Centers for Medicare & Medicaid Services' data indicates that some Medicare prescription drug plans and state Medicaid programs reimbursed for some obesity drugs in 2016 and 2017. Coverage for private health insurance plans also varied, and plans may require the patient to obtain prior authorization for the drugs to be covered, according to officials from insurers and pharmacy benefit managers GAO interviewed. For example, officials from one insurer said that some of their plans only cover obesity drugs after a patient has tried other treatment options such as behavioral counseling.