{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,23]],"date-time":"2026-08-23T15:15:49Z","timestamp":1787498149831,"version":"build-2736575974"},"reference-count":17,"publisher":"BMJ","issue":"9","license":[{"start":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T00:00:00Z","timestamp":1757980800000},"content-version":"unspecified","delay-in-days":15,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Open"],"accepted":{"date-parts":[[2025,8,7]]},"published-print":{"date-parts":[[2025,9]]},"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>The increasing prevalence of overweight and obesity among individuals with type 1 diabetes (T1D) complicates glycaemic management and escalates insulin resistance, necessitating innovative therapeutic strategies. Tirzepatide, a dual agonist for glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide receptors, shows promise in managing weight and glycaemic control in type 2 diabetes but is unexplored in the context of T1D. This double-blind, placebo-controlled randomised trial will evaluate the efficacy of tirzepatide in adults with T1D and overweight\/obesity over 32 weeks.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods and analysis<\/jats:title>\n                    <jats:p>\n                      60 participants (aged 18\u201370 years) with a body mass index \u226527\u2009kg\/m\n                      <jats:sup>2<\/jats:sup>\n                      and HbA1c\u226410%\u2009will be randomised 1:1 to receive either tirzepatide or a placebo, alongside standard insulin therapy. The primary outcome is the change in body weight (%). Secondary measures include change in HbA1c (%), proportion of body weight lost (&gt;5%, &gt;10%, &gt;15% and &gt;20%), changes in insulin dosage, time in range by continuous glucose monitoring (CGM) criteria and severity of comorbidities. Compliance, adverse events and medication interactions will be closely monitored, with adjustments made for tolerability. Patient-reported outcomes and experiences will be measured to capture the benefits of glycaemic management, weight management and quality of life. To compare the means of body weight reduction (%) between the tirzepatide and control groups, an independent samples t-test will be employed under the assumption that data are normally distributed. Secondary outcome measures will be analysed by Student\u2019s t-test. All data will be reported as group means with confidence intervals, with default statistical significance assumed at p&lt;0.05.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Ethics and dissemination<\/jats:title>\n                    <jats:p>Ethical approval has been obtained from the Northern Sydney Local Health District\u2019s Human Research Ethics Committee (approval ID #2024\/ETH00180).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Trial registration number<\/jats:title>\n                    <jats:p>\n                      <jats:ext-link xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" ext-link-type=\"clintrialgov\" xlink:href=\"NCT06180616\">NCT06180616<\/jats:ext-link>\n                      .\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.1136\/bmjopen-2024-093775","type":"journal-article","created":{"date-parts":[[2025,9,17]],"date-time":"2025-09-17T06:25:41Z","timestamp":1758090341000},"page":"e093775","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":5,"title":["Tirzepatide for the treatment of adults living with concurrent type 1 diabetes and overweight or obesity (TZP-T1D): a double-blind, placebo-matched randomised controlled trial protocol"],"prefix":"10.1136","volume":"15","clinical-trial-number":[{"clinical-trial-number":"nct06180616","registry":"10.18810\/clinical-trials-gov"}],"author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-5728-6054","authenticated-orcid":false,"given":"Amanda R","family":"Purcell","sequence":"first","affiliation":[{"name":"Kolling Institute of Medical Research, St Leonards, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Natassia","family":"Rodrigo","sequence":"additional","affiliation":[{"name":"Kolling Institute of Medical Research, St Leonards, New South Wales, Australia"},{"name":"The University of Sydney Faculty of Medicine and Health, Sydney, New South Wales, Australia"},{"name":"Department of Diabetes, Endocrinology and Metabolism, Royal North Shore Hospital, St Leonards, New South Wales, Australia"},{"name":"Department of Diabetes and Endocrinology, Nepean Hospital, Penrith, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3795-2254","authenticated-orcid":false,"given":"Matilda S G","family":"Longfield","sequence":"additional","affiliation":[{"name":"Kolling Institute of Medical Research, St Leonards, New South Wales, Australia"},{"name":"Department of Diabetes, Endocrinology and Metabolism, Royal North Shore Hospital, St Leonards, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9317-1348","authenticated-orcid":false,"given":"Sarah J","family":"Glastras","sequence":"additional","affiliation":[{"name":"Kolling Institute of Medical Research, St Leonards, New South Wales, Australia"},{"name":"The University of Sydney Faculty of Medicine and Health, Sydney, New South Wales, Australia"},{"name":"Department of Diabetes, Endocrinology and Metabolism, Royal North Shore Hospital, St Leonards, New South Wales, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"239","published-online":{"date-parts":[[2025,9,16]]},"reference":[{"key":"2025091623251923000_15.9.e093775.1","doi-asserted-by":"publisher","DOI":"10.1007\/s00125-021-05571-8"},{"key":"2025091623251923000_15.9.e093775.2","doi-asserted-by":"crossref","first-page":"715","DOI":"10.1038\/s41574-021-00542-w","article-title":"One hundred years of insulin therapy","volume":"17","author":"Mathieu","year":"2021","journal-title":"Nat Rev Endocrinol"},{"key":"2025091623251923000_15.9.e093775.3","doi-asserted-by":"publisher","DOI":"10.1089\/dia.2018.0384"},{"key":"2025091623251923000_15.9.e093775.4","doi-asserted-by":"crossref","first-page":"61","DOI":"10.1111\/imj.15426","article-title":"Glycaemic outcomes in Australasian children and adults with type 1 diabetes: failure to meet targets across the age spectrum","volume":"53","author":"Holmes-Walker","year":"2023","journal-title":"Intern Med J"},{"key":"2025091623251923000_15.9.e093775.5","doi-asserted-by":"publisher","DOI":"10.1111\/pedi.12166"},{"key":"2025091623251923000_15.9.e093775.6","doi-asserted-by":"publisher","DOI":"10.1016\/j.diabres.2017.01.012"},{"key":"2025091623251923000_15.9.e093775.7","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1007\/s13679-022-00477-x","article-title":"Highlighting the role of obesity and insulin resistance in type 1 diabetes and its associated cardiometabolic complications","volume":"11","author":"Karamanakos","year":"2022","journal-title":"Curr Obes Rep"},{"key":"2025091623251923000_15.9.e093775.8","doi-asserted-by":"crossref","unstructured":"Cantley NW , Lonnen K , Kyrou I , et al . 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