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Compounds · Semaglutide

The C-cell question: rodent findings and their human context

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SG
s.grahameTL2Member13 Mar 2025#1

Posting this under the heading it deserves: The C-cell question: rodent findings and their human context Everything below is what sits behind that.

I have seen STEP 8 (JAMA, 2022) cited in support of a claim I do not think it supports, twice this month, so I would like to work through what it actually shows.

My reading is that the trial is sound for its own question and is being stretched to answer a different one. I might be wrong about that, which is why this is a topic rather than a correction.

What I would like from this discussion: someone who disagrees with me to say why, with the section of the paper they are relying on.

0 likes 17mo
SR
sa.rasmussenTL2 Moderator21 Mar 2025#2

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.

2 likes 16mo
ST
sterile_tableTL3Regular26 Mar 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.

12 likes 16mo
SL
s.lindqvistTL2 Moderator30 Mar 2025#4

Coming back to post #2, because the follow-up matters more than the original answer.

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.

26 likes 16mo
FR
figure_reviewTL2Member4 Apr 2025#5
sterile_table, 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

post #4 is right about the mechanism and I think understates the practical bit.

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 in reply to #3 16mo
JM
j.marchettiTL2 Moderator8 Apr 2025#6

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.

0 likes 16mo
N
NorringtonTL3Regular12 Apr 2025#7

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.

8 likes 16mo
EK
e.kuipersTL2 Moderator16 Apr 2025#8

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.

19 likes 15mo
LM
lyophil_marginTL3Regular19 Apr 2025#9
e.kuipers, post #8: 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. Go to post

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.

1 like in reply to #8 15mo
MY
m.yildizTL2 Moderator23 Apr 2025#10

On post #6 — agreed on the reasoning, with one qualification.

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.

7 likes 15mo
NR
n.rowntreeTL3Regular26 Apr 2025#11
j.marchetti, post #6: 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. Go to post

Coming back to post #9, because the follow-up matters more than the original answer.

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.

1 like in reply to #6 15mo
RB
r.bakkenTL2 Moderator30 Apr 2025#12
s.lindqvist, post #4: Coming back to post #2, because the follow-up matters more than the original answer. 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… 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 #4 15mo
TT
titrate_traceTL1Member3 May 2025 · edited#13

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.

25 likes 15mo
EF
e.ferreiraTL3Regular6 May 2025#14

post #13 answers the question as asked. The question underneath it is different.

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.

12 likes 15mo
TN
t.nardoneTL3Regular9 May 2025#15

I read post #13 twice before replying, because I had assumed the opposite.

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.

0 likes 15mo
NA
n.achebeTL2 Moderator13 May 2025#16
s.lindqvist, post #4: Coming back to post #2, because the follow-up matters more than the original answer. 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… Go to post

This follows post #13 rather than contradicting it.

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 in reply to #4 15mo
AP
abstract_peakTL1Member16 May 2025#17

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.

18 likes 14mo
BC
b.correiaTL2 Moderator19 May 2025#18

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.

8 likes 14mo
VD
vial_deskTL3Regular22 May 2025#19

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 14mo
AE
a.eriksenTL2 Moderator25 May 2025 · edited#20
sterile_table, 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

Picking up post #17: that is the part I would want checked first.

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.

26 likes in reply to #3 14mo
OV
o.vogelTL2 Moderator28 May 2025#21
n.achebe, post #16: This follows post #13 rather than contradicting it. 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… 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 #16 14mo
AZ
a.zamoraTL2 Moderator31 May 2025#22

Coming back to post #20, because the follow-up matters more than the original answer.

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.

4 likes 14mo
NN
n.norgaardTL2 Moderator3 Jun 2025#23

post #22 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.

19 likes 14mo
MD
m.duarteTL2 Moderator5 Jun 2025#24

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 14mo
BN
b.nwosuTL2 Moderator8 Jun 2025#25

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 14mo
MS
m.stephanopoulosTL3Regular11 Jun 2025#26

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.

2 likes 14mo
GV
g.verhoevenTL2 Moderator14 Jun 2025 · edited#27

post #26 is right about the mechanism and I think understates the practical bit.

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.

13 likes 13mo
RS
r.scholtenTL2Member17 Jun 2025#28
titrate_trace, post #13: 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. Go to post

Worth separating two things that post #24 runs together.

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.

27 likes in reply to #13 13mo
RA
r.aldana_pharmdTL4Pharmacist19 Jun 2025#29
r.scholten, post #28: Worth separating two things that post #24 runs together. 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… Go to post

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.

4 likes in reply to #28 13mo
SO
s.okaforTL2 Moderator22 Jun 2025#30
Norrington, post #7: 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. 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.

12 likes in reply to #7 13mo