Dieters spent £47million last year on pills and diet aids; it’s no wonder that so many companies want a slice of this lucrative cake. The first slimming pill to be approved for sale over the counter appeared in the UK last month. However, rimonabant, the canabinoid receptor antagonist, was withdrawn six months after it became available on the NHS, when the European Medicines Agency found its benefits as an anti-obesity treatment were outweighed by an increased risk of psychiatric disorders.
Dr Nat Monck of Cancer Research Technology and SCI’s Fine Chemicals Group, tackles some of the key questions raised around this topic.
Why is obesity still a growing health issue?
Dr Monck: I’d guess the issue is simple thermodynamics – the maths of (food) energy in versus energy out still hasn’t been understood by the majority of patients. Take, for example, one biscuit a day as an extra treat; if the energy is not needed by the body, this will lead to an increase in body weight by as much as 10lbs over a year (Dr Paul Super, recent Channel 4 programme The Hospital). Even a modest reduction in body weight in the obese can lessen the risks of other diseases developing.
Are the US Food & Drug Association’s (FDA) required endpoints for the chronic treatments of obesity and diabetes too high, especially on safety, to attract new research into metabolic disorders?
Dr Monck: The FDA has had to raise the safety levels because people treated with pharmaceuticals tend to benefit in terms of health and quality of life, but often are not ‘cured’ of their disorders. Long-term treatments come with instructions to maintain a balanced diet and life-style with appropriate exercise. While the current treatments can manage patients’ health, perhaps further research will establish robust hypotheses and mechanisms behind these disorders, leading to better treatments.
Beyond the thermodynamics mentioned earlier, not all of the mechanisms that lead to the development of obesity are fully understood, especially the part that the brain plays in these. Also, only some of the mechanisms leading to diabetes are fully understood.
Considering the failure of the central CB1 approach and the moderate effects on 5-HT2C agonist lorcaserin published earlier this year, are there novel approaches that look encouraging?
Dr Monck: The topics covered in the agenda for the Metabolic Disorders Symposium being held at the SCI hope to cover current and novel approaches towards treating diabetes and obesity. Professor Stephen Bloom (Imperial College, London) will open by reviewing the state of current approaches and new targets for the medical area. This will be followed by international speakers from Astra-Zeneca, Prosidion, Roche, 7TM, AMRI and NeuroSearch, presenting progress towards targets including DGAT1 inhibitors, melanin-concentrating hormone receptor antagonists, glucokinase activators and 11b- HSD inhibitors as potential new treatments for metabolic disorders.
See also Metabolic disorders
Dr Caroline Low, Imperial College London and SCI's Fine Chemicals Group