The UK Government’s latest scheme to increase access to the anti-diabetic drug semaglutide is designed to reduce levels of obesity and related complications. But past evidence suggests it is doomed to fail. Rod Tucker finds out more.
A two-year pilot scheme, backed by investment up to £40m, is to be launched in the UK to increase accessibility to the anti-obesity treatment semaglutide outside of hospital settings.
Obesity is a leading cause of conditions such as cardiovascular disease, diabetes and cancer, and was reported to be a factor in more than one million admissions to NHS hospitals in 2019/20. According to information released by the Department of Health and Social Care, obesity has an annual cost to the NHS of £6.5bn.
On the face of it, the rationale for widening access to the anti-diabetic treatment appears sensible. Any approach that leads to a reduction in the level of obesity should give rise to a commensurate decrease in the number of individuals developing obesity-related conditions and requiring interventions such as knee and hip replacements. If obesity levels drop, so would the waiting list for these complications. Its a win-win situation.
But there are two other relevant considerations. Firstly, does wider access to semaglutide align with current recommendations for the drug, and secondly, how likely is it that the pilot scheme will be successful?
Current recommendations for semaglutide
In March 2023, NICE recommended semaglutide as an option for weight management in adults, alongside a reduced-calorie diet and increased physical activity. However, there were several caveats attached to this recommendation.
Firstly, use of the drug was restricted to a maximum of two years and it could only be prescribed at a specialist weight management service. Secondly, patients were required to have at least one weight-related comorbidity and body mass index (BMI) of at least 35.0 kg/m2, although patients could access the drug if they had a BMI of 30.0 kg/m2 to 34.9 kg/m2 and met the criteria for referral to specialist services.
By broadening access to semaglutide, the pilot scheme is therefore at variance to the NICE guidance. While NICE is sponsored by the Department of Health and Social Care, and purported to be independent of the UK Government, it has been argued that the organisation is not, and indeed cannot be, truly indepenent of the Government.
To date, NICE has remained silent on the Government’s latest initiative, probably because it goes against everything that was outlined in its draft guidance. The Government has argued that its latest scheme is merely a pilot project to explore if and how the anti-diabetic drug can be made safely available outside of a hospital settings. This will happen, it says, alongside NHS England’s work to implement NICE’s recommendations to make this new class of treatment available to patients through established specialist weight management services.
Is semaglutide the answer?
The evidence for semaglutide is convincing, but it is important to acknowledge that the drug only works when used as an adjunct to diet and exercise. Moreover, it is likely to require life-long use despite the two year restriction imposed by NICE. It is now clear that significant weigh re-gain occurs once patients stop taking the anti-diabetic drug, and another study shows how mean body weight increased by 6.9% after cessation of treatment.
A further barrier to the potential success of the pilot scheme is the growing recognition that obesity is a complex condition and that hypothalamic neuro-inflammatory responses play an important role. As a result, obesity management requires a multi-interventional approach.
Will the new pilot scheme work?
Commenting on the pilot scheme, the UK health and social care secretary Steve Barclay said: ‘This next generation of obesity drugs have the potential to help people lose significant amounts of weight when prescribed with exercise, diet and behavioural support.’
But how effective is a primary-based weight management service likely to be? An insightful analysis of GP and nurse practitioner habits in response to a mock scenario, makes for interesting reading. Published in 2020, the study found that overall only 24% of respondents would refer patients to a weight management service. The most common response, in over 80% of cases, was to provide either diet or exercise-based advice.
Despite this, evidence from the US offers some hope that behaviour-based weight loss interventions, either with or without weight loss medications, result in more weight loss than usual care conditions.
The potential for greater access to an effective anti-diabetic weight loss drug is to be welcomed. Nevertheless, it can only ever serve to address the consequences and not the root causes of obesity. A huge amount of evidence also makes it abundantly clear that obesity is inextricably linked to socioeconomic and demographic factors. Overweight and obesity are far more prevalent in deprived areas, in those of black ethnicity and in the least well educated. In fact, someone living in the most deprived area is nearly twice as likely to be obese as someone in the least deprived area.
With past behaviour seen as the best predictor of future behaviour, the evidence over the last 30 years does not augur well for the current pilot scheme. A recent analysis has shown how obesity policy in England has involved 14 strategies, published from 1992 to 2020, which contain 689 wide-ranging policies. The authors suggested that the continued failure to reduce the prevalence of obesity in England for almost three decades may be due to either weaknesses in the policies’ design, or to failures of implementation and evaluation.
Obesity represents a growing problem, with 25.9% of adults in England obese and 37.9% overweight. Moreover, we live in an obesogenic environment that is influenced by the availability and affordability of foods, together with varying access to opportunities for physical activity. Consequently, it is perhaps too simplistic to label obesity as an individual’s problem: obesity is an environmental problem that requires a wholesale change with regulatory interventions directed at reducing intake of ultra-processed food and acknowledgement of the impact of socioeconomic factors. Such a change requires additional funding, and considerably more that the currently allocated £40m.
Greater access to the anti-diabetic drug semaglutide is unlikely to single-handedly solve the problem of obesity. Nonetheless, if provided through an adequately funded weight management services as part of a comprehensive package that includes behavioural support, access to exercise facilities and nutritional advice, it might have a noticeable effect on levels of obesity and its health-related consequences.
