{"id":1381,"date":"2026-09-03T10:36:00","date_gmt":"2026-09-03T10:36:00","guid":{"rendered":"https:\/\/vistaralabs.ca\/tirzepatide-human-trials-weight-diabetes\/"},"modified":"2026-09-04T08:24:44","modified_gmt":"2026-09-04T08:24:44","slug":"tirzepatide-human-trials-weight-diabetes","status":"publish","type":"post","link":"https:\/\/vistaralabs.ca\/fr\/tirzepatide-human-trials-weight-diabetes\/","title":{"rendered":"Tirzepatide Trials: Weight and Diabetes"},"content":{"rendered":"<p><strong>Tirzepatide has one of the deepest trial records of any compound in the research-peptide catalogue.<\/strong> Three large, randomized Phase 3 trials, published in <em>The Lancet<\/em>, <em>JAMA<\/em>, and the <em>New England Journal of Medicine<\/em>, cover its effect on weight, on maintaining that weight, and on diabetes risk.<\/p>\n<h2>Findings<\/h2>\n<ul class=\"vl-findings\">\n<li>In a 72-week trial of adults with obesity and type 2 diabetes, tirzepatide produced average weight loss of up to about <strong>15%<\/strong>, versus about 3% on placebo.<\/li>\n<li>People who stayed on it kept losing weight; those switched to placebo regained most of what they had lost.<\/li>\n<li>Three-year data shows sustained weight loss of close to <strong>20%<\/strong>.<\/li>\n<li>Tirzepatide is an approved medication, so its evidence comes from large randomized trials.<\/li>\n<\/ul>\n<h2>SURMOUNT-2: weight reduction (Lancet, 2023)<\/h2>\n<p>This 72-week, double-blind, placebo-controlled Phase 3 trial enrolled 938 adults living with obesity and type 2 diabetes across seven countries, randomized to once-weekly tirzepatide 10 mg, 15 mg, or placebo. Both tirzepatide doses produced substantial and clinically meaningful bodyweight reduction versus placebo, with a safety profile consistent with the drug class.<\/p>\n<h2>SURMOUNT-4: keeping the weight off (JAMA, 2024)<\/h2>\n<p>After a 36-week open-label lead-in in which 670 participants lost a mean of 20.9%, they were randomized to continue tirzepatide or switch to placebo for 52 weeks. Those who continued lost a further 5.5%; those switched to placebo regained 14% \u2014 a 19.4-point difference. Overall, 89.5% of the continued-treatment group kept at least 80% of their earlier weight loss, versus 16.6% on placebo.<\/p>\n<h2>Three-year outcomes (NEJM, 2024)<\/h2>\n<p>In a 176-week trial of 2,539 participants with obesity (of whom 1,032 also had prediabetes), mean weight change was -19.7% on 15 mg, -18.7% on 10 mg, and -12.3% on 5 mg, versus -1.3% on placebo. Fewer participants on tirzepatide progressed to type 2 diabetes.<\/p>\n<h2>What tirzepatide is<\/h2>\n<p>Tirzepatide is a dual agonist: it activates both the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. It sits between single-receptor compounds and the triple-receptor <a href=\"https:\/\/vistaralabs.ca\/where-to-get-retatrutide-canada\/\">retatrutide<\/a>, a comparison our <a href=\"https:\/\/vistaralabs.ca\/retatrutide-vs-tirzepatide\/\">retatrutide vs tirzepatide article<\/a> lays out.<\/p>\n<div class=\"vl-note\">\n<p>Vistara Labs stocks <a href=\"https:\/\/vistaralabs.ca\/tirzepatide-10mg\/\">tirzepatide 10&nbsp;mg<\/a> research vials, shipped from within Canada to every province.<\/p>\n<\/div>\n<h2>Frequently asked questions<\/h2>\n<h3>How much weight did tirzepatide produce in trials?<\/h3>\n<p>In the SURMOUNT-2 Phase 3 trial of adults with obesity and type 2 diabetes, tirzepatide produced substantial, clinically meaningful weight reduction over 72 weeks versus placebo. In a separate 3-year trial, participants on 15 mg reached a 19.7% mean weight reduction.<\/p>\n<h3>Does the weight come back if tirzepatide is stopped?<\/h3>\n<p>The SURMOUNT-4 trial addressed exactly this. After a 36-week lead-in producing 20.9% mean weight loss, those who continued tirzepatide kept losing (a further 5.5%), while those switched to placebo regained 14%. Continued treatment maintained the loss; withdrawal reversed much of it.<\/p>\n<h3>Did tirzepatide affect diabetes risk?<\/h3>\n<p>In the 3-year trial of people with obesity and prediabetes, tirzepatide produced a markedly lower rate of progression to type 2 diabetes than placebo, alongside sustained weight reduction.<\/p>\n<p class=\"vl-citation\"><em>Sources: Garvey WT, et al. Tirzepatide for obesity in type 2 diabetes (SURMOUNT-2). Lancet. 2023;402:613-626. <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/37385275\/\" rel=\"nofollow noopener\" target=\"_blank\">PMID 37385275<\/a>. Aronne LJ, et al. Continued tirzepatide for weight maintenance (SURMOUNT-4). JAMA. 2024;331:38-48. <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/38078870\/\" rel=\"nofollow noopener\" target=\"_blank\">PMID 38078870<\/a>. Jastreboff AM, et al. Tirzepatide for Obesity Treatment and Diabetes Prevention. N Engl J Med. 2025;392:958-971. <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/39536238\/\" rel=\"nofollow noopener\" target=\"_blank\">PMID 39536238<\/a>.<\/em><\/p>\n<p><script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"How much weight did tirzepatide produce in trials?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"In the SURMOUNT-2 Phase 3 trial of adults with obesity and type 2 diabetes, tirzepatide produced substantial, clinically meaningful weight reduction over 72 weeks versus placebo. In a separate 3-year trial, participants on 15 mg reached a 19.7% mean weight reduction.\"}}, {\"@type\": \"Question\", \"name\": \"Does the weight come back if tirzepatide is stopped?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The SURMOUNT-4 trial addressed exactly this. After a 36-week lead-in producing 20.9% mean weight loss, those who continued tirzepatide kept losing (a further 5.5%), while those switched to placebo regained 14%. Continued treatment maintained the loss; withdrawal reversed much of it.\"}}, {\"@type\": \"Question\", \"name\": \"Did tirzepatide affect diabetes risk?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"In the 3-year trial of people with obesity and prediabetes, tirzepatide produced a markedly lower rate of progression to type 2 diabetes than placebo, alongside sustained weight reduction.\"}}]}<\/script><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Three Phase 3 trials of tirzepatide, published in the Lancet, JAMA and NEJM, on weight reduction, keeping weight off, and lower diabetes risk. A 19.7% mean weight reduction at three years.<\/p>","protected":false},"author":1,"featured_media":1285,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","_vistara_fr_title":"","_vistara_fr_desc":"","_vl_research_product":1152,"footnotes":""},"categories":[33],"tags":[],"vl_research_area":[36],"class_list":["post-1381","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-peptide-research"],"_links":{"self":[{"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/posts\/1381","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/comments?post=1381"}],"version-history":[{"count":2,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/posts\/1381\/revisions"}],"predecessor-version":[{"id":1452,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/posts\/1381\/revisions\/1452"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/media\/1285"}],"wp:attachment":[{"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/media?parent=1381"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/categories?post=1381"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/tags?post=1381"},{"taxonomy":"vl_research_area","embeddable":true,"href":"https:\/\/vistaralabs.ca\/fr\/wp-json\/wp\/v2\/vl_research_area?post=1381"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}