Guide

Stopping a GLP-1: What SURMOUNT-4 Found, and What It Means for Planning

In SURMOUNT-4, participants withdrawn from tirzepatide regained 14.0% of body weight over 52 weeks while those continuing lost a further 5.5%. That is the strongest evide

The trial that answers this

SURMOUNT-4 enrolled participants who had completed a 36-week open-label lead-in on tirzepatide, then randomised them to continue or switch to placebo for 52 weeks.

Those continuing lost a further 5.5% of body weight. Those withdrawn regained 14.0%.

That is a clean answer to a question people ask constantly, and it is why obesity is increasingly described as a chronic condition managed rather than an episode treated. The medication works while it is present.

What that does not mean

It does not mean regain is universal or complete — 14% is a mean, and the distribution around it is wide. It does not mean stopping is a failure. And it does not mean nobody maintains a result afterwards.

What it does mean is that maintaining without the medication is a different project from losing with it, and one that has not been solved by the trials. Anyone telling you otherwise is ahead of the evidence in either direction.

Why people stop

Cost. The most common reason, and the one this publication can actually help with — see insurance coverage before concluding the price is fixed.

Side effects. 4.3% to 7.1% of SURMOUNT-1 participants discontinued for adverse events depending on dose.

Coverage loss. A formulary exclusion or a plan change, which has its own route.

Supply interruption. Particularly relevant for compounded products while the 503B bulks proposal is unresolved.

Reaching a goal. The one the trial speaks to most directly, and the one where the evidence is least comfortable.

What to discuss before stopping

1. Is stopping the only option? Cost has routes. Side effects have dose options. Coverage has appeals.
2. Is there a lower maintenance dose that works? This is the intermediate option SURMOUNT-4 did not test — it compared continuation at maximum tolerated dose against complete withdrawal, not reduction.
3. What is the plan for the year after? The regain in the trial accrued over 52 weeks rather than immediately.
4. What will you monitor? Weight, but also the metabolic markers that improved.
5. What would trigger restarting, and is that route open to you?

Tapering

There is no established tapering protocol with trial evidence behind it. SURMOUNT-4 withdrew participants to placebo rather than tapering them, so the comparison between abrupt cessation and gradual reduction has not been made.

Prescribers reduce doses for good clinical reasons and that is a legitimate judgement. It is judgement rather than evidence, and it should be described that way — particularly by anyone selling a microdose programme as a maintenance strategy, which is an extrapolation from a trial that tested something else.

The financial planning point

If the evidence points to indefinite treatment, the number that matters is not the annual cost but the sustainable monthly cost at a maintenance dose. A rate you can hold for years beats a lower rate you abandon after eight months — because on this evidence, abandoning it returns you toward where you started.

That is the strongest practical argument for establishing coverage before comparing self-pay routes, and for comparing programmes at 10 mg rather than at the advertised entry price.

Questions readers actually ask