Mapping Models of Tirzepatide Delivery for Obesity Management in Primary Care Settings
Early implementation of tirzepatide in primary care has been slow, with no significant increase in prescribing for obesity management observed after the policy change.
Where it sits
this study against the rest of the semaglutide corpusSummary and findings
The study evaluated the early implementation of tirzepatide for obesity management in primary care in England, focusing on service delivery models and prescribing trends. It involved 23 of 42 Integrated Care Boards (ICBs) and examined prescribing activity from June 2025 to January 2026. The findings indicated a slow and heterogeneous implementation process with no significant increase in obesity-related prescribing following the policy introduction.
Abstract
<h4>Structured abstract</h4> <h4>Objectives</h4> To evaluate the early implementation of tirzepatide for the management of obesity in primary care in England, including variations in Integrated Care Board (ICB) service delivery models, access criteria, and initial prescribing activity following national policy introduction (June 2025). This paper reports the initial phase of a wider mixed methods national evaluation of tirzepatide delivery models for initial priority cohorts defined in NHS England interim commissioning guidance. <h4>Design</h4> National study combining 1) mapping of ICB implementation plans using a questionnaire, publicly available data and documents, and stakeholder discussions, and 2) analysis of English Prescribing Dataset (EPD) to investigate tirzepatide prescribing trends using interrupted time-series methods to compare monthly prescriptions before and after June 2025 (implementation start) against a synthetic control series based on semaglutide prescribing. <h4>Setting</h4> ICBs across England. <h4>Participants</h4> 23/42 ICBs (55%) responded, of which 13 also took part in stakeholder meetings. For 17 ICBs (40%), we additionally extracted information from publicly available documents. <h4>Main outcome measures</h4> Descriptions of service delivery models, access criteria, and ICB characteristics; stakeholder-reported implementation challenges; and prescribing trends over time. <h4>Results</h4> We were able to categorise models of care for 40/42 ICBs. A general practice-led delivery model was most commonly planned (18/40; 45%), followed by community/local-based delivery (8; 20%), custom models (8; 20%), and specialist weight management service (SWMS) community outreach (6; 15%). Four ICBs (10%) planned to use more than one model of care. Most ICBs reported following national priority cohort eligibility criteria 31/39 (79%), while eight (21%) applied additional prioritisation criteria due to funding constraints. Stakeholder discussions highlighted variation in the interpretation of model definitions, variation in operationalisation, and challenges related to affordability, insufficient workforce capacity, and tight timelines, with some ICBs not yet prescribing at the time of stakeholder meetings (November 2025). Analyses of EPD showed a steady increase in tirzepatide prescribing over time, with no evidence that the June 2025 policy implementation date produced any additional increase beyond background diabetes-related trends. <h4>Conclusions</h4> Early implementation of tirzepatide prescribing in primary care has been characterised by heterogeneous service models, local adaptations of access criteria, and slow implementation of obesity-related prescribing. Findings highlight the challenges of implementing new pharmacological treatments including patient management within routine care and the need for clear guidance, realistic timelines, and system capacity. Ongoing evaluation is needed to understand how service models evolve and implications for access, equity, and outcomes. <h4>Summary boxes</h4> <h4>What is already known on this topic</h4> Clinical trials have demonstrated the effectiveness of new obesity management medications such as tirzepatide for weight loss when combined with behavioural interventions. Tirzepatide has been approved for obesity management in the NHS, with a phased implementation in primary care due to concerns about affordability to expand access to treatment. How to deliver these treatments in routine practice, to ensure equity of access, is not yet well understood due to evolving service models and a need for real-world evaluation. <h4>What this study adds</h4> Early implementation of tirzepatide in primary care in England has been slow and heterogeneous, with variation in delivery models and some local adaptation of eligibility criteria in response to funding and workforce constraints. Between June 2025 and January 2026, there was no detectable change in prescribing attributable to obesity beyond expected background trends for diabetes, suggesting no clear early impact on obesity-related prescribing.