Presentation (CTI)

Problem Statement: 16% of adults live with obesity globally, including 6.5 million in the UK. Obesity is estimated to reduce life expectancy by 3-10 years. Randomized clinical trials demonstrated that obesity pharmacotherapies statistically significantly reduced the body mass index (BMI) of adults with obesity over 68-72 weeks compared to diet and exercise interventions alone, but economic modelling was required to understand the lifetime cost-effectiveness. Stakeholders needed to understand the impact of introducing new technologies for a large population into a healthcare system, and whether they could be delivered within existing infrastructure. This included defining the comparator and lifestyle support adjunct to pharmacological treatment and the associated costs, consideration of duration of treatment (lifetime, or any proposed stopping rules), estimating long-term BMI trajectories, and predicting long-term costs and effectiveness of reducing obesity-related complications. Due to the population size and potential for lifetime treatment, the decision risk and budget impact were large, and so consideration of uncertainty was particularly important.
Description: In economic models, risk equations linked patient characteristics and surrogate markers (principally BMI) to clinical events including diabetes and cardiovascular conditions. Scenario analyses were used to consider rate of weight regain after stopping pharmacotherapy, and relative differences in BMI between people remaining on pharmacotherapy (for longer than data were available) and people only receiving diet and exercise support. The residual impact of having previously lived with obesity was considered a key uncertainty. Scenario analyses were also used to address uncertainty regarding delivery and costs of the comparator and support provided alongside pharmacotherapy, and whether these could be delivered within primary care or required specialist weight management services. A phased introduction was required for one technology due to the considerable effort required to set up delivery of an obesity treatment in primary care, with a plan to re-evaluate this funding variation.
Lessons Learned: The appraisals highlighted the challenges of predicting lifetime cost-effectiveness from short-term clinical trial data, the role of economic models in analysing different scenarios, and the importance of real-world evidence for estimating long-term outcomes. The HEOR evidence was essential in determining that obesity pharmacotherapies are reimbursed, and highlighted evidence gaps that real world evidence can address.
Stakeholder Perspective: The perspective is that of the National Institute for Health and Care Excellence (NICE), with input from members of the Technology Appraisal Committee who evaluated the technologies, NICE technical staff who wrote the guidance, and the independent assessment group who reviewed the HEOR evidence.