Top-dose phentermine/topiramate cost-effective after 5 years for adolescents with obesity
Click Here to Manage Email Alerts
Key takeaways:
- Lifestyle counseling is more cost-effective than anti-obesity medications at 13 months and 2 years for adolescents with obesity.
- Semaglutide exceeded the study’s willingness-to-pay threshold at all time points.
Top-dose phentermine/topiramate as an adjunct to lifestyle counseling is the most cost-effective strategy for treating adolescents with obesity over 5 years, according to findings from an economic microsimulation model.
“In this economic evaluation, we used a simulation model to examine the cost-effectiveness of three anti-obesity medications adjunct to lifestyle counseling to treat adolescents with obesity,” Chin Hur, MD, MPH, professor of medicine and epidemiology and director of health care innovations research and evaluation at Columbia University Irving Medical Center, and colleagues wrote in a study published in JAMA Network Open. “Anti-obesity medications were not estimated to be cost-effective compared with lifestyle counseling alone at 13 months and 2 years. At 5 years, top-dose phentermine and topiramate was projected to be the preferred strategy, with an incremental cost-effectiveness ratio of $56,876 per quality-adjusted life-years gained vs. lifestyle counseling.”
Researchers used a patient-level microsimulation model for treating adults with obesity to analyze the cost-effectiveness of lifestyle counseling alone and adjunct to liraglutide 3 mg daily (Saxenda, Novo Nordisk), mid-dose phentermine 7.5 mg plus topiramate 46 mg daily (Qsymia, Vivus), top-dose phentermine 15 mg plus topiramate 92 mg, and semaglutide 2.4 mg weekly (Wegovy, Novo Nordisk) for adolescents with obesity. The model simulated a hypothetical group of 100,000 adolescents with baseline characteristics similar to what was observed in clinical trials (mean age, 15 years; 58% girls; mean BMI, 37 kg/m2). Cost-effectiveness was assessed at 13 months, 2 years and 5 years. The CMS National Average Drug Acquisition Cost was used to determine the base monthly cost of medications. The cost of lifestyle counseling was estimated from a family-based intervention for pediatric obesity.
Treatment was considered cost-effective if it had an incremental cost-effectiveness ratio (ICER) of less than $100,000 per QALY gained. The best treatment or intervention at each time point was determined to be the one with the most life-years gained while being cost-effective.
At 13 months, liraglutide results in higher costs and fewer QALYs gained than top-dose phentermine/topiramate, whereas mid-dose phentermine/topiramate had a higher cost per QALY than top-dose phentermine/topiramate. Top-dose phentermine/topiramate was not cost-effective, with an ICER of $317,010 per QALY gain compared with lifestyle counseling.
At 2 years, liraglutide and mid-dose phentermine/topiramate both had higher costs and fewer QALYs gained than top-dose phentermine/topiramate. Top-dose phentermine-topiramate was not cost-effective at 2 years, though the ICER dropped to $138,045 per QALY compared with lifestyle counseling. At 5 years, top-dose phentermine/topiramate became the preferred therapy, with an ICER of $56,876 per QALY compared with lifestyle counseling.
At each time point, semaglutide was projected to add the most QALYs. However, compared with top-dose phentermine/topiramate, semaglutide’s ICER exceeded the willingness-to-pay threshold. In a sensitivity analysis, the monthly cost of semaglutide would need to be reduced by 97.5% at 13 months, 89.4% at 2 years and 85.2% at 5 years for it to become cost-effective.
“Though semaglutide was the only strategy estimated to have a BMI reduction relative to baseline at 5 years, its monthly price of nearly $1,300 resulted in an ICER well above our willingness-to-pay threshold,” the researchers wrote. “The high cost of anti-obesity medications, especially out-of-pocket, is a major barrier that may discourage patients from receiving or adhering to the aggressive treatment that the American Academy of Pediatrics recommends.”
In a probability sensitivity analysis using a willingness-to-pay threshold of $100,000 per QALYs gained, lifestyle counseling was the preferred strategy 100% of the time at 13 months and 81.3% of the time at 2 years. At 5 years, top-dose phentermine/topiramate was preferred 84.3% of the time and lifestyle counseling was preferred 10.7% of the time.
“Long-term clinical trials are needed to fully understand the safety, efficacy and cost-effectiveness of anti-obesity medications in adolescents,” the researchers wrote.
Perspective
Back to Top
Obesity in adolescents and adults is increasingly being recognized as a chronic disease requiring long-term treatment. Evaluation of the cost-effectiveness of anti-obesity medications is therefore necessary, in terms of public and private health care policy, patient access to treatment and medication adherence.
This study by Lim and colleagues is believed to be the first cost-effectiveness study to compare liraglutide, phentermine and topiramate, and semaglutide for the treatment of obesity in adolescents. While these proprietary medications are clearly effective and well tolerated, their current annual costs will limit widespread adoption by patients, their families and their physicians.
Collapse
Click Here to Manage Email Alerts