With Catherine Thomas, MS, and Scott Isaacs, MD
Even with the alarming rates of excessive weight and obesity, clinicians have shown a reticence toward prescribing new antiobesity pharmacotherapies--and a new study from researchers at Weill Cornell Medical College’s Comprehensive Weight Loss Center quantified just how hesitant clinicians are about recommending pharmacotherapy for weight management.1
“The adoption rate of SGLT2s was nearly exponential, while the adoption rate of new anti-obesity pharmacotherapies was linear,” said Catherine Thomas, MS, lead author of the study, and clinical research coordinator for the weight control center. “There have been other studies that have looked at this phenomenon in smaller cohorts, but ours is the first nationwide study to document this.”
The mean increase in monthly prescriptions for the newest generation antiobesity medications, including naltrexone+bupropion (Contrave), lorcaserin (Belviq), and topiramate+phentermine (Qsymia), was 5,154 per month from January 2012 and July 2015.1 In contrast, SGL2 inhibitors for diabetes--a new class of drugs that entered the market around the same time—saw an average of 25,259 new prescriptions written during the same time period.
This [pattern] reflects an existing awareness among prescribers of the value of antidiabetes pharmacotherapies and a comfort with using them, suggesting that the disparity between antiobesity medications and SGL2 prescriptions must not be due to barriers such as pharmacotherapy initiation and adherence, according to the researchers.
“It seems that the overriding reason for a lack of prescriptions to manage obesity as compared to diabetes are cost and lack of insurance reimbursement,”1 said Ms. Thomas. For example, the current cost of the new antiobesity medications range from about $165 to $199 per month, where as the SGLT2 inhibitors cost around $343 per month.
“Yet, the diabetes medications are almost universally covered by health insurance, often under Tier 1, which requires the lowest patient copay,” said Ms. Thomas.
“Insurance coverage is very limited for antiobesity drugs,” said Scott Isaacs, MD, director of Atlanta Endocrine Associates, and a member of the EndocrineWeb editorial board in confirmed this reimbursement discrepancy.
“Some patients do get [limited] coverage, if their employer opts into a weight loss benefit, but most do not," said Dr. Isaacs. "Medicare and Medicaid do not cover these drugs, and HMOs typically do not cover them either.”
It is established practice that a modest weight loss of even 10% can reverse many weight-related cardiometabolic risk factors, including elevated serum glucose, hyperlipidemia, and hypertension.2 However, most individuals struggle even to achieve this modest weight loss given the complexity of biopsychosocial influences that impede permanent weight control changes for most overweight and obese individuals.2
“While the value of these medications to patients may help control weight gain and reduce the risks of related comorbid conditions, they have not been shown to reverse obesity over the long term,” said Dr. Isaacs. Patients must stay on pharmacotherapies aimed at reversing obesity in order to retain any benefits.
“If someone goes off of these medications, they will likely gain back all the weight they’ve lost,” Dr. Isaacs said.
Safety concerns may be another reason for the overwhelming reluctance of clinicians to readily prescribe weight loss pharmacotherapies.1 Both the withdrawal of several antiobesity medications from the market in the 1990s, and the modest results achieved with these medications may have contributed to their unpopularity.3
“The newest generation of [obesogenic] medications came out over a year ago, and some of the formulations have been out for 4 years, so I feel pretty confident in their safety data,” Dr. Isaacs said. But he noted that serious health problems with previous weight loss medications such as fenfluramine/phentermine and sibutramine (Meridia) likely led to heightened caution. Also, unfamiliarity with the newest pharmacotherapies, may contribute to clinicians’ hesitation to prescribe these agents.
Endocrinologists have an important role to play in the adoption, and are best able to appropriately use anti-obesity medications to their patients benefit, according to Ms. Thomas.
“Endocrinologists, out of all the specialists, other than those in obesity medicine, are probably best suited to treat obesity medically because they are used to treating diabetes with titrating insulin,” Ms. Thomas said. “That’s exactly how antiobesity medications are most successfully used, by tweaking doses.”
“Obesity is a hormonal condition, and endocrinologists should be taking an active role in treating it. After all, about 45% of the US population has indications necessitating treatment with antiobesity pharmacotherapies, yet as the study shows, only 2% are being treated,” Dr. Isaacs said.
“To have this exponential adoption of an antidiabetes medication and just a limited adoption of a weight loss medications makes no sense to me,” said Dr. Isaacs. “It makes a lot more sense to use an antiobesity drug to treat diabetes, because you’re treating the cause of the disease, not the symptom.”
As of August 2015, the number of dispensed antidiabetes prescriptions, excluding insulin, was 15 times the number of antiobesity prescriptions filled. SGLT2s represented barely 5% of the diabetes medication market share.1
The study confirmed similar prescriber behaviors of physicians who wrote both anti-obesity pharmacotherapies and SGLT2s. Of the 900,000 prescribers in the database, 12% prescribed a new antiobesity pharmacotherapy and 11% prescribed an SGLT2. The researchers relied on blinded data from the IMS Health National Prescription database to perform a retrospective analysis.