The semaglutide extension followed a selected group
The STEP 1 extension followed 327 participants after the main treatment period. Semaglutide and the structured lifestyle intervention were stopped at week 68. Over the following year, the semaglutide group regained about two-thirds of its previous weight loss on average, while some improvement remained relative to baseline.
This was an exploratory extension in a subset of the original trial. Because medication and the lifestyle intervention were both discontinued, the finding should not be presented as an isolated test of one particular stopping strategy. It also does not mean every person will regain the same amount.
SURMOUNT-4 randomized continuation and withdrawal
SURMOUNT-4 first provided open-label tirzepatide for 36 weeks, then randomized 670 participants without diabetes to continue treatment or switch to placebo. Over the next 52 weeks, mean weight changed by an additional 5.5% reduction with continuation and a 14.0% increase with placebo, measured from the randomization weight.
The denominator matters: the reported 14.0% is not a claim that participants regained fourteen percentage points of their original baseline weight. The participants had already lost weight before randomization. The trial tested defined injectable treatment, not compounded formulations or an internet tapering protocol.
These studies support planning, not a universal rule
Both studies show that substantial regain can follow withdrawal, while their designs and populations differ. They support discussing long-term treatment and follow-up. They do not establish that medication must continue unchanged for every person regardless of tolerability, contraindications or preferences.
Before an elective change, ask what the next plan is intended to achieve and how it will be assessed. Reasons for stopping matter: a cost interruption, pregnancy plan, adverse effect and completed clinical reassessment are different situations.
Sources: Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension - PMC · Continued Treatment With Tirzepatide for Maintenance of Weight Reduction in Adults With Obesity: The SURMOUNT-4 Randomized Clinical Trial - PMC · Prescription Medications to Treat Overweight & Obesity - NIDDK
Arrange support before a preventable gap
If cost or provider access is the problem, tell the clinician before the prescription runs out. Ask whether another clinically appropriate pathway, pharmacy or coverage process can help. A cheaper advertisement does not guarantee treatment continuity or product equivalence.
Keep nutrition, activity and clinical follow-up in the discussion. Agree on which observations to record and who to contact if your health or symptoms change. These studies do not provide a guaranteed way to prevent all regain after discontinuation.
Sources: Prescription Medications to Treat Overweight & Obesity - NIDDK · Nutritional priorities to support GLP-1 therapy for obesity: A joint advisory from the American College of Lifestyle Medicine, the American Society for Nutrition, the Obesity Medicine Association, and the Obesity Society - PMC
Do not turn trial averages into a restart prescription
The withdrawal evidence does not tell you to reuse an old dose after a long interruption or to spread injections farther apart. Restarting or changing medicine needs product-specific and clinical review. Provide the last dose and the duration of the break when contacting the prescriber.
Use the research to ask better questions about continuation, alternatives and monitoring. A measured maintenance plan is more useful than a promise that one person’s approach will reproduce a trial average.
Sources: Wegovy prescribing information · Zepbound prescribing information