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Abstract ObjectiveIncretin mimetics are revolutionizing obesity treatment, but high prices and supply shortages limit patient access. Some clinicians have suggested less frequent dosing as an off‐ramping strategy to maintain weight loss, but this approach lacks published evidence regarding its weight loss efficacy. We aim to provide such clinical evidence and to rationalize these results with mathematical modeling. MethodsWe present a real‐world case series of two patients who took their incretin mimetic less frequently than recommended. We complement this case report with a pharmacokinetic‐pharmacodynamic model of virtual patients that simulates long‐term weight change with semaglutide and tirzepatide administered at various frequencies. ResultsBoth real‐world and virtual patients maintained significant weight loss under reduced dosing frequencies. Our results indicate that reducing frequency does not commensurately reduce efficacy. The majority of weight loss persists even when patients wait 2, 3, or perhaps even 4 weeks between doses. ConclusionsOur findings support the hypothesis that less frequent administration of incretin mimetics can be a viable and cost‐saving long‐term weight maintenance strategy in conjunction with sustained lifestyle modification. Further research is warranted to validate the effectiveness of this off‐label approach, define optimal dosing regimens to meet individual patient needs, and evaluate the cost–benefit implications.
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Alternative dosing regimens of GLP ‐1 receptor agonists may reduce costs and maintain weight loss efficacy
Abstract AimsTo discover alternative dosing regimens of incretin mimetics that simultaneously reduce costs and maintain weight loss efficacy. As a secondary objective, we used our results to explore how allocating a limited incretin mimetics budget could affect public health on a national scale. Materials and MethodsWe used mathematical modelling and simulation of semaglutide and tirzepatide to investigate dosing regimens which have not yet been studied clinically. For semaglutide, we used a recent pharmacokinetic (PK) and pharmacodynamic (PD) model. For tirzepatide, we used a recent PK model and modelled PD by reparameterizing the semaglutide PD model to fit tirzepatide clinical data. ResultsReducing dose frequency does not commensurately reduce weight loss. For example, merely switching from one dose per week (q1wk) to one dose every 2 weeks (q2wk) maintains roughly 75% of the weight loss. Furthermore, if the decrease in dose frequency involves an appropriate increase in dose size, then approximately 100% of the weight loss is maintained. In addition, we compared offering incretin mimetics to (1) a fraction of obese US adults with q1wk dosing versus (2) twice as many obese US adults with q2wk dosing. Though scenarios (1) and (2) require the same budget, our analysis suggests that (2) reduces national obesity and mortality to a much greater degree. ConclusionOur study highlights the potential utility of alternative dosing regimens of incretin mimetics. Compared with standard once‐weekly dosing, costs can be halved and weight loss maintained. These cost‐saving results have implications for patients, physicians, insurers, and governments.
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- PAR ID:
- 10571955
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Diabetes, Obesity and Metabolism
- Volume:
- 27
- Issue:
- 4
- ISSN:
- 1462-8902
- Format(s):
- Medium: X Size: p. 2251-2258
- Size(s):
- p. 2251-2258
- Sponsoring Org:
- National Science Foundation
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