Reading SURMOUNT-1 without the press release — one year on posts 31–51

Categorical response thresholds — the proportion reaching ten, fifteen or twenty per cent reduction — are more persuasive and less informative than the mean. They depend entirely on where the threshold was drawn.

That is all I can say without guessing.

Right — I had this wrong and I am glad to have read it before it mattered.

Narrowing post #30, because the general version has more than one answer.

SURMOUNT-1 reported weight reduction of a magnitude that was the largest for a pharmacological intervention at that time of publication. It also reported a clear dose response across three doses. The categorical thresholds (people reaching 10%, 15%, 20% loss) got the most attention but read less informatively than the mean weight change.

SURMOUNT-4's randomised withdrawal design is the strongest available evidence about what happens on stopping. It says nothing about a lower maintenance dose, because the comparison was continue versus placebo rather than continue versus less.

Gastrointestinal effects were comparable in character to the GLP-1 monoagonists across the programme. Individual reports here vary in both directions, which is what you would expect from a between-person difference rather than a between-drug one.

Caveat: everything above assumes the paperwork is what it says it is.

Post #33 and I disagree about the size of the effect, not about the direction.

Injection-site reactions were reported at a low but non-zero rate across the trials. The practical point is that a reaction at one site does not predict a reaction at the next, and rotating properly makes the question moot.

I am confident about the direction and much less about the magnitude.

Research-use-only tirzepatide is not approved for human use and is not made to pharmaceutical standards. Anyone discussing it here is describing what they did, not recommending it.

Reading it again, the caveat matters more than the finding.

Appreciated. The plain phrasing does more work here than a longer post would.

Worth separating two things that post #36 runs together.

Two people in this thread mean different things by Reading SURMOUNT-1 without the press and are disagreeing about the definition while believing they are disagreeing about the facts. Worth pausing to define it.

Categorical response thresholds — the proportion reaching ten, fifteen or twenty per cent reduction — are more persuasive and less informative than the mean. They depend entirely on where the threshold was drawn.

Scoping that to what I have actually seen rather than what I have read.

Post #41 is right about the mechanism and I think understates the practical bit.

Something worth flagging about Reading SURMOUNT-1 without the press: the strongest-sounding claims in this thread are the ones with no source attached, which is the usual pattern and not a coincidence.

On post #41 — agreed on the reasoning, with one qualification.

The 2.5 mg starting dose is a tolerance step and not a therapeutic one. Judging efficacy at that dose is the single commonest reasoning error in this subcategory.

SURMOUNT-OSA is notable because it used an objective physiological endpoint, the apnoea-hypopnoea index, rather than a symptom scale. Two parallel trials, with and without positive airway pressure, addressed the confounder directly. The reduction was substantial in both.

That is my reading. Someone else read the same page differently and was reasonable.