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Eight weeks in, and nothing yet

Trial participants who had not lost 5% by week 8 still reached a clinically meaningful result by week 72 — just a smaller one than those who had.

Wesley Jenkins6 min read
Sorted at week 8, followed to week 72week 8week 72lost ≥5% by week 8lost <5% by week 8Shape only —no figureswere published

Two months in, several hundred dollars spent, and the scale has barely moved. It is the moment the most expensive decision in this market gets made, usually alone and usually without any information — and it arrives long before the six-month total anybody planned for.

What was analyzed

Researchers took the tirzepatide-treated participants from the two SURMOUNT trials — 1,775 from the trial in people without type 2 diabetes and 609 from the trial in people with it, 2,384 in total — and sorted them by their week-8 result. [1] Those who had lost at least 5% of their body weight by then were classed as early responders; those who had not were not. Both groups were then followed to week 72.

Early responders differed from the rest at baseline: they were more likely to be female, more likely to be White, and had lower starting HbA1c. That matters for how to read everything that follows, because nobody was assigned to a group. People sorted themselves by how their own bodies behaved.

What happened by week 72

Both groups achieved clinically meaningful weight reduction and improvements in cardiometabolic risk parameters including HbA1c. The early responders did significantly better on both.

The abstract does not publish the week-72 figures for each group, so this page does not quote any. What it establishes is the direction: a slow start predicted a smaller result, and it did not predict no result.

The tolerability finding is the useful one

Gastrointestinal side effects were similar between the groups in pattern, severity and time course. That undercuts an intuition a lot of people hold: that feeling sick means the drug is working, and feeling fine means it is not.

On this evidence, how much nausea somebody had told you nothing about whether they were losing weight quickly. People who lost little in eight weeks were not spared the side effects, and people who lost a lot were not punished with more of them. It is also a reason to be careful with what a seller charges for a gentler experience, since tolerability and result appear to move independently.

What this cannot tell you

Whether becoming an early responder would help. Nobody was made into one. The comparison is between two groups of people who differed before the drug started and continued to differ after, so it describes prognosis rather than cause.

There is also no placebo arm inside this analysis. Only tirzepatide-treated participants were included, so “clinically meaningful” here is measured against where people started, not against an untreated comparison — a distinction worth holding onto whenever a result is reported as change from baseline.

The money version of the question

A buyer at week 8 is deciding whether to commit to roughly ten more months. If the published figures for each group existed, that decision could be priced. They do not, so it cannot be — and anybody presenting a precise expectation from this analysis is supplying a number the paper did not.

What can be said is that stopping at week 8 forecloses a result this analysis says was still available, and that continuing is a real cost against a smaller expected return. Most people do not complete a year anyway — persistence in this market is poor and not only because of price. That is a conversation for a prescriber, not an intake form.

Frequently asked

Should I stop if I have lost nothing by week 8?
This analysis does not answer that, and the decision belongs with a prescriber. It does show that participants who had not lost 5% by week 8 still reached a clinically meaningful result by week 72, though a smaller one than early responders.
How much smaller?
The abstract does not publish week-72 figures for the two groups, so no percentage appears on this page. Only the direction of the difference is established.
Do side effects tell you whether it is working?
Not here. Gastrointestinal events were similar in pattern, severity and time course between early responders and everyone else.
Can I become an early responder?
Nothing in this analysis addresses that. Nobody was assigned to a group — people sorted themselves by how they responded, and the two groups differed before treatment began.

Sources

  1. [1] Kokkinos A, et al. (2026). Tirzepatide Efficacy and Tolerability According to Early Weight Response: A Post Hoc Analysis of the SURMOUNT-1 and SURMOUNT-2 Trials Diabetes, Obesity and Metabolism. PMID 42348366

Where to get it

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