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Compounds · Semaglutide

What SELECT changed about how semaglutide is discussed, and what it did not

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Solved by a.eriksen in post #6
Semaglutide versus liraglutide in STEP 8: semaglutide produced greater weight reduction and the discontinuation rates differed. But the trial was open-label for the dosing schedule, which admits expectation effects. Weekly versus daily itself is part of the comparison, not a confounding variable to be removed.

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PF
p.friskTL2 Moderator29 Jan 2025#1

Asking directly, because I could not find a straight answer: What SELECT changed about how semaglutide is discussed, and what it did not

Session topic: SURMOUNT-1 (N Engl J Med, 2022). Please read it before posting; the discussion is much better when everyone has.

The question I would like us to start with is what the trial set out to estimate, rather than what it found. Once that is on the table we can talk about whether the design could have answered it, and only then about the numbers.

Specific things I would like covered: the population and how far it generalises, how discontinuation was handled, whether the comparator was a fair one, and what the absolute rather than relative effect looks like.

I will summarise at the end and the summary will feed the relevant digest page.

37 likes 18mo
TV
t.verhoevenTL2 Moderator1 Feb 2025#2

Coming back to the opening post, because the follow-up matters more than the original answer.

The C-cell question: semaglutide triggered medullary thyroid carcinoma in rodent toxicology studies. A signal in rodents does not automatically appear in humans, but it is the reason the compound is contraindicated in people with personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2.

0 likes 18mo
VD
vial_deskTL3Regular2 Feb 2025#3

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

0 likes 18mo
EM
e.mensaTL2 Moderator4 Feb 2025#4

The 165 to 184 hour range: that is roughly 7 to 7.6 days, which is why the weekly schedule works. Below 4 half-lives you are not approaching steady state yet, which is the pharmacological argument for the four-week step interval.

5 likes 18mo
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BBramleyTL3Regular6 Feb 2025#5
p.frisk, post #1: Asking directly, because I could not find a straight answer: What SELECT changed about how semaglutide is discussed, and what it did not Session topic: SURMOUNT-1 ( N Engl J Med , 2022). Please read it before posting; the discussion is much better when everyone has. The question I would like us to start with is what the trial set out to… Go to post

This follows post #2 rather than contradicting it.

The SELECT trial changed the positioning because it was the first cardiovascular outcome trial in people without diabetes. That decoupled the cardiovascular argument from glycaemic control, which is why it mattered beyond its own numbers.

14 likes in reply to #1 18mo
AE
a.eriksenTL2 Moderator Solution7 Feb 2025#6

Semaglutide versus liraglutide in STEP 8: semaglutide produced greater weight reduction and the discontinuation rates differed. But the trial was open-label for the dosing schedule, which admits expectation effects. Weekly versus daily itself is part of the comparison, not a confounding variable to be removed.

28 likes 18mo
TN
t.nardoneTL3Regular8 Feb 2025#7

The opalescent appearance in semaglutide solutions is occasionally noted and the mechanism is unclear. It does not appear to correlate with product failure in practice. Visible particles or frank cloudiness is different and would be reason to contact the supplier.

0 likes 18mo
CS
c.serranoTL210 Feb 2025#8
JV
j.vandermolenTL3Regular11 Feb 2025 · edited#9
c.serrano, post #8: Worth separating two things that post #4 runs together. Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing. The correction was fair and I had been repeating something I had not checked carefully enough. Go to post

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

0 likes in reply to #8 18mo
IA
i.amankwahTL2 Moderator12 Feb 2025#10
p.frisk, post #1: Asking directly, because I could not find a straight answer: What SELECT changed about how semaglutide is discussed, and what it did not Session topic: SURMOUNT-1 ( N Engl J Med , 2022). Please read it before posting; the discussion is much better when everyone has. The question I would like us to start with is what the trial set out to… Go to post

On alcohol: the labelling does not contraindicate it, but it raises gastric irritation risk and semaglutide already does that. There is no published interaction study and the conservative position is to limit it if you are titrating or if gastrointestinal symptoms are troublesome.

0 likes in reply to #1 17mo
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TavaresTL113 Feb 2025#11
PB
p.boatengTL2 Moderator15 Feb 2025#12
p.frisk, post #1: Asking directly, because I could not find a straight answer: What SELECT changed about how semaglutide is discussed, and what it did not Session topic: SURMOUNT-1 ( N Engl J Med , 2022). Please read it before posting; the discussion is much better when everyone has. The question I would like us to start with is what the trial set out to… Go to post

Albumin binding is not a unique structural feature and nothing in the class lacks it, but the reversibility matters. Semaglutide binds albumin covalently through a fatty side chain, which creates a very long half-life at the cost of sequestering the free form. That is a trade-off and it is the trade-off that allows weekly dosing.

19 likes in reply to #1 17mo
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BramleyTL2Member16 Feb 2025#13

Practical note that does not fit anywhere else. Whatever you conclude from this topic, write down what you did and when. The single most useful thing in your own records is not any individual result; it is that they are dated and consecutive.

4 likes 17mo
RC
r.chukwuTL2 Moderator17 Feb 2025#14

The STEP programme populations were selected: enrollment criteria required baseline body mass index over 30, no recent blood pressure crisis, no recent retinopathy, no renal disease at the time. Applying results from that population to someone well outside it is an extrapolation and should be called one.

0 likes 17mo
BP
bench_peakTL3Regular18 Feb 2025#15
vial_desk, post #3: Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up. Go to post

Worth separating two things that post #11 runs together.

Is there a ceiling dose beyond which the effect plateaus? The trials did not study that because they stopped at 2.4 mg. Some people report trying higher doses, but trial data is absent and off-label dosing enters territory this site does not advise on.

0 likes in reply to #3 17mo
TB
t.batistaTL2 Moderator19 Feb 2025#16

post #15 is right about the mechanism and I think understates the practical bit.

Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up.

26 likes 17mo
LC
l.chevalierTL3Regular20 Feb 2025 · edited#17

Gastric emptying delay is the mechanism behind most of the gastrointestinal side effects. Slowing the stomach empties it feeds less food into the intestines at a time, which is part of the satiety mechanism but is also why nausea is dose-dependent and titration-dependent.

8 likes 17mo
MA
m.adebayoTL2 Moderator21 Feb 2025#18

The opalescent appearance in semaglutide solutions is occasionally noted and the mechanism is unclear. It does not appear to correlate with product failure in practice. Visible particles or frank cloudiness is different and would be reason to contact the supplier.

2 likes 17mo
TN
t.nardoneTL3Regular23 Feb 2025#19
t.verhoeven, post #2: Coming back to the opening post, because the follow-up matters more than the original answer. The C-cell question: semaglutide triggered medullary thyroid carcinoma in rodent toxicology studies. A signal in rodents does not automatically appear in humans, but it is the reason the compound is contraindicated in people with personal or… Go to post

The C-cell question: semaglutide triggered medullary thyroid carcinoma in rodent toxicology studies. A signal in rodents does not automatically appear in humans, but it is the reason the compound is contraindicated in people with personal or family history of medullary thyroid carcinoma or multiple endocrine neoplasia type 2.

0 likes in reply to #2 17mo
NA
n.achebeTL2 Moderator24 Feb 2025 · edited#20

post #19 answers the question as asked. The question underneath it is different.

Approved indications differ by jurisdiction and change. As of mid-2026 the weight-management indication is approved in many European jurisdictions but not all, and access is still narrower in others. For your own region, check the regulatory website rather than a forum summary.

0 likes 17mo
MA
mi.almeidaTL2 Moderator25 Feb 2025#21
vial_desk, post #3: Thank you for the correction. I have edited my earlier post with a note rather than silently, so the thread still makes sense to read. The error was mine and it was the kind that comes from remembering a figure instead of looking it up. Go to post

For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.

15 likes in reply to #3 17mo
NT
n.torrenceTL3Regular26 Feb 2025#22

Is there a ceiling dose beyond which the effect plateaus? The trials did not study that because they stopped at 2.4 mg. Some people report trying higher doses, but trial data is absent and off-label dosing enters territory this site does not advise on.

30 likes 17mo
KA
k.agyemanTL2 Moderator27 Feb 2025#23

This follows post #20 rather than contradicting it.

The 165 to 184 hour range: that is roughly 7 to 7.6 days, which is why the weekly schedule works. Below 4 half-lives you are not approaching steady state yet, which is the pharmacological argument for the four-week step interval.

0 likes 17mo
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VThorvaldsenTL328 Feb 2025#24
NS
ni.stanescuTL2 Moderator1 Mar 2025#25
a.eriksen, post #6: Semaglutide versus liraglutide in STEP 8: semaglutide produced greater weight reduction and the discontinuation rates differed. But the trial was open-label for the dosing schedule, which admits expectation effects. Weekly versus daily itself is part of the comparison, not a confounding variable to be removed. Go to post

The SELECT trial changed the positioning because it was the first cardiovascular outcome trial in people without diabetes. That decoupled the cardiovascular argument from glycaemic control, which is why it mattered beyond its own numbers.

10 likes in reply to #6 17mo
AR
ambient_reviewTL3Regular2 Mar 2025#26

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

23 likes 17mo
AP
a.petrovTL2 Moderator3 Mar 2025#27

Picking up post #24: that is the part I would want checked first.

On alcohol: the labelling does not contraindicate it, but it raises gastric irritation risk and semaglutide already does that. There is no published interaction study and the conservative position is to limit it if you are titrating or if gastrointestinal symptoms are troublesome.

0 likes 17mo
SP
s.poulsenTL3Regular4 Mar 2025#28
ni.stanescu, post #25: The SELECT trial changed the positioning because it was the first cardiovascular outcome trial in people without diabetes. That decoupled the cardiovascular argument from glycaemic control, which is why it mattered beyond its own numbers. Go to post

The mass figure differs between sources because of how the different entities report it. The monoisotopic mass of the bare peptide is one number; the mass including the acylation is another. Different sources emphasise different details.

1 like in reply to #25 17mo
IC
i.coelhoTL2 Moderator5 Mar 2025#29

post #28 is right about the mechanism and I think understates the practical bit.

Semaglutide versus liraglutide in STEP 8: semaglutide produced greater weight reduction and the discontinuation rates differed. But the trial was open-label for the dosing schedule, which admits expectation effects. Weekly versus daily itself is part of the comparison, not a confounding variable to be removed.

6 likes 17mo
PA
p.amankwahTL2 Moderator6 Mar 2025#30
BBramley, post #5: This follows post #2 rather than contradicting it. The SELECT trial changed the positioning because it was the first cardiovascular outcome trial in people without diabetes. That decoupled the cardiovascular argument from glycaemic control, which is why it mattered beyond its own numbers. Go to post

Worth separating two things that post #26 runs together.

The STEP programme populations were selected: enrollment criteria required baseline body mass index over 30, no recent blood pressure crisis, no recent retinopathy, no renal disease at the time. Applying results from that population to someone well outside it is an extrapolation and should be called one.

16 likes in reply to #5 17mo