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1.4k questions · page 60 of 60

26 votes 5 answers26k views
What did the placebo arm of TRIUMPH-1 report for fatigue?

Concretely: TRIUMPH-1 · fatigue. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics change…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
gi-side-effects
gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

416 questions
nausea
nausea

The dominant tolerability signal in every trial of the class: incidence, timing relative to a dose step, duration, and the distinction between…

346 questions
asked by orla_ferriter 47k · 11 months ago
26 votes 3 answers25k views
What does splitting a weekly dose actually cost in vial entries and compounded measurement error?

Most discussion of splitting a weekly dose treats the costs as vague — "more injections", "more chances for contamination". I would like the costs quantified, because…

split-dosing
split-dosing

Dividing a weekly dose across more than one administration. Questions here concern the pharmacokinetic rationale, whether the peak-to-trough ratio…

39 questions
sterility
sterility

Sterility as a test result rather than an adjective. Covers what a sterility test actually measures, why "sterile filtered" on a document is close…

122 questions
dead-space
dead-space

The volume trapped in the syringe hub and needle after the plunger bottoms out. It is small in absolute terms and large as a fraction of a small…

110 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

811 questions
insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

268 questions
asked by orla_sheridan 14k · 13 months ago
26 votes5 answers25k views
How do I convert the STEP 2 hazard ratio into an absolute risk reduction?

I have the full paper rather than the abstract, and the supplementary appendix. I would rather understand the derivation than memorise the outcome. Two people I asked…

cardiovascular
cardiovascular

Cardiovascular outcomes: the SELECT major-adverse-event result, SOUL, SUSTAIN 6 and REWIND, how to convert a hazard ratio into an absolute risk…

111 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

811 questions
asked by teodora_ilic 15k · 14 months ago
26 votes 2 answers25k views
How does mazdutide behave on a C8 column compared to survodutide?

Details up front: mazdutide · a C8 column · survodutide. I have used one of these for a while and I am considering switching, which requires a reason. What I care…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
reference-standard
reference-standard

Certified reference materials and in-house standards: traceability, the certificate of the standard itself, system suitability, and why every…

179 questions
asked by drawn_and_capped 15k · 16 months ago
26 votes 5 answers25k views
Why did two TFC lots of oral semaglutide differ on content assay?

Conditions: TFC · oral semaglutide. I think I have a problem. I am not yet sure whether it is a real problem or a measurement artefact. I want to know whether this is…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

438 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by dermot_kiely 14k · 18 months ago
26 votes 5 answers25k views
Would you re-test orforglipron after eight weeks at minus 20 °C, or accept the original certificate?

Stated plainly: orforglipron · eight weeks · minus 20 °C. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not…

batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
peptide-stability
peptide-stability

The chemistry of peptide degradation: deamidation, oxidation, hydrolysis, aggregation and fibrillation, and how temperature, pH, ionic strength,…

832 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by swirl_dont_shake 19k · 13 months ago
26 votes 5 answers25k views
Why do two papers on SOUL report different headline figures?

I have the full paper rather than the abstract, and the supplementary appendix. I can predict the outcome but I cannot explain it, which means I will get the next…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

811 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

360 questions
asked by m_haraldsen 38k · 9 months ago
26 votes0 answers25k views
What does an HPLC purity test add for orforglipron that a purity figure does not?

What I have: an HPLC purity test · orforglipron. I have used one of these for a while and I am considering switching, which requires a reason. What I care about is…

content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

438 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by ekaterina_volk 16k · 2.1 years ago
26 votes 5 answers24k views
Would you accept 99.1% on orforglipron from QYB without a content assay?

Details up front: 99.1% · orforglipron · QYB. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can tell me which…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
content-assay
content-assay

Quantified content: how many milligrams of peptide are actually in the vial, measured against a calibrated reference standard. A separate test…

438 questions
vendor-vetting
vendor-vetting

Evaluating a supplier on evidence rather than reputation: testing history across batches, whether certificates are batch-specific, how failures…

436 questions
asked by p_mkhize 41k · 8 months ago
26 votes 3 answers24k views
Is the top of the ladder the most effective dose, or just the highest one that was studied?

The label maximum gets treated as a destination — the "full dose", as though anything below it is partial. But a label maximum is the highest dose a sponsor took…

dose-escalation
dose-escalation

The decision to move up a step: what evidence supports a four-week interval, what happens when you compress it, and how trial protocols handled…

88 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
tirzepatide
tirzepatide

A dual GIP and GLP-1 receptor agonist. Questions here cover the SURPASS and SURMOUNT programmes, the practical differences from a pure GLP-1…

162 questions
retatrutide
retatrutide

An investigational GLP-1, GIP and glucagon receptor tri-agonist, studied in the TRIUMPH programme. Not approved anywhere. Use this tag for…

14 questions
maintenance-dose
maintenance-dose

Staying put: the lowest dose that holds a result, the difference between the maximum studied dose and the maximum useful dose, and what the…

44 questions
asked by sample_id 17k · 6 months ago
26 votes 3 answers24k views
Does holding at 10 mg for twelve weeks before escalating reduce early satiety?

The case in front of me: 10 mg · twelve weeks · early satiety. I want to know whether this is a real physical effect or an artefact of how it is measured. What…

titration
titration

Stepwise dose increases over weeks, why the label schedules exist at all, and what tolerability-driven deviation from a schedule looks like in…

444 questions
nausea
nausea

The dominant tolerability signal in every trial of the class: incidence, timing relative to a dose step, duration, and the distinction between…

346 questions
dose-escalation
dose-escalation

The decision to move up a step: what evidence supports a four-week interval, what happens when you compress it, and how trial protocols handled…

88 questions
asked by coldpack_88 37k · 18 months ago
26 votes 5 answers24k views
What does 95.2% purity on a C4 column actually tell me about a retatrutide vial?

The case in front of me: 95.2% · a C4 column · retatrutide. The figures are clear enough; the question is what they mean and what they do not. I can supply the…

hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
asked by Dr_Yusuf_Adeyemi 95k · 9 months ago
26 votes5 answers23k views
What is the reported incidence of vomiting on orforglipron in STEP 1?

What I have: vomiting · orforglipron · STEP 1. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to…

gi-side-effects
gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

416 questions
clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
nausea
nausea

The dominant tolerability signal in every trial of the class: incidence, timing relative to a dose step, duration, and the distinction between…

346 questions
asked by void_volume 13k · 20 months ago
26 votes0 answers22k views
What is the real-world lead time from Tianjin to New Zealand in winter?

For reference: Tianjin · New Zealand. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably comfortable…

international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

427 questions
cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

524 questions
customs
customs

Customs handling: how declarations are assessed, why a parcel sits at a facility for a week, seizure notices, and the practical difference between…

186 questions
asked by two_two_micron 15k · 17 months ago
26 votes0 answers22k views
Is a JEEP order from Nantong likely to hold cold chain to Norway?

Details up front: JEEP · Nantong · Norway. I would rather over-plan the first cycle and simplify later. I am prepared to do the work if someone can tell me which work…

cold-chain
cold-chain

Keeping material within a temperature window from manufacture to use: phase-change packs versus dry ice, thermal mass, transit-lane temperature…

524 questions
international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

427 questions
vendor-comparison
vendor-comparison

Side-by-side comparison of suppliers on measurable axes - independently confirmed purity and content, lead time, cold-chain handling,…

351 questions
asked by two_point_four 14k · 21 months ago
26 votes 5 answers22k views
What does TRIUMPH-3 actually establish about mazdutide?

Stated plainly: TRIUMPH-3 · mazdutide. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I do…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
semaglutide
semaglutide

A GLP-1 receptor agonist with a fatty-acid-acylated backbone and a roughly one-week half-life, marketed for type 2 diabetes and for weight…

360 questions
cardiovascular
cardiovascular

Cardiovascular outcomes: the SELECT major-adverse-event result, SOUL, SUSTAIN 6 and REWIND, how to convert a hazard ratio into an absolute risk…

111 questions
orforglipron
orforglipron

A non-peptide, orally bioavailable small-molecule GLP-1 receptor agonist studied in the ATTAIN programme. It is not a peptide, which changes…

14 questions
asked by kelvin_lam 11k · 19 months ago
26 votes 5 answers22k views
How many units on a U-40 insulin syringe is a 4 mg dose at 10 mg/mL?

Setup, so nobody has to ask: a U-40 insulin syringe · 4 mg · 10 mg/mL. The units are where I keep going wrong, so please be explicit about them. I have sanity-checked…

dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

811 questions
insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

268 questions
reconstitution
reconstitution

Taking a lyophilised vial to a solution of known concentration: choice of diluent, volume selection, how to add liquid without shearing the cake,…

330 questions
asked by gel_pack_warm 13k · 8 months ago
26 votes0 answers21k views
Why has a parcel to Spain sat at a customs facility for twenty-one days?

What I have: Spain · twenty-one days. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and…

customs
customs

Customs handling: how declarations are assessed, why a parcel sits at a facility for a week, seizure notices, and the practical difference between…

186 questions
international-shipping
international-shipping

Cross-border movement of research material: transit lanes and their thermal profiles, tracked versus untracked, declaration accuracy, and what…

427 questions
import-regulations
import-regulations

The legal framework for personal importation across major jurisdictions, enforcement discretion, and the distinction between a research reference…

53 questions
asked by zeynep_arslan 20k · 2.2 years ago
26 votes 5 answers21k views
What did the placebo arm of SURMOUNT-1 report for dizziness?

What I am working with: SURMOUNT-1 · dizziness. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
gi-side-effects
gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

416 questions
nausea
nausea

The dominant tolerability signal in every trial of the class: incidence, timing relative to a dose step, duration, and the distinction between…

346 questions
asked by harriet_lonsdale 14k · 7 months ago
26 votes5 answers21k views
What fraction of loss on tirzepatide is lean mass according to STEP 2?

The particulars: tirzepatide · STEP 2. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably comfortable…

lean-mass
lean-mass

Lean body mass as measured rather than assumed: what DEXA, BIA and air-displacement plethysmography each actually estimate, the body-composition…

164 questions
muscle-loss
muscle-loss

Loss of contractile tissue during energy deficit: what fraction of total loss is lean mass, why the commonly quoted figures are measurement…

82 questions
dexa
dexa

Dual-energy X-ray absorptiometry: what it measures, its precision limits, why hydration state and scan positioning move the numbers, and how to…

84 questions
asked by bridget_nyathi 16k · 19 months ago
26 votes 5 answers21k views
What did the placebo arm of FLOW report for reflux?

What I am working with: FLOW · reflux. I have read the primary source rather than the summary, which has left me with more questions. I understand the headline. I do…

clinical-trials
clinical-trials

Reading the primary literature properly: estimands, intention-to-treat versus per-protocol, confidence intervals, absolute versus relative…

913 questions
gi-side-effects
gi-side-effects

The gastrointestinal cluster as a whole - nausea, vomiting, diarrhoea, constipation, reflux, early satiety - with trial incidence rates, dropout…

416 questions
nausea
nausea

The dominant tolerability signal in every trial of the class: incidence, timing relative to a dose step, duration, and the distinction between…

346 questions
asked by two_two_micron 15k · 11 months ago
26 votes 2 answers21k views
How do I get 10 units out of a vial reconstituted to 10 mg/mL without guessing?

What I have: 10 units · 10 mg/mL. I would like to understand the steps well enough to explain them to someone else. I have access to a refrigerator with a logger and…

insulin-syringe
insulin-syringe

U-100 and U-40 insulin syringes as measuring instruments. A U-100 syringe is graduated in insulin units where 100 units equals 1 mL, so one unit…

268 questions
dosing-math
dosing-math

The arithmetic itself: milligrams to millilitres to insulin units, concentration after reconstitution, dose per draw, and vial-days per vial. Show…

811 questions
diluent-volume
diluent-volume

Choosing how much diluent to add, which is really a question about what you want your measurement resolution to be. Larger volumes buy you…

308 questions
asked by anja_hellstrom 13k · 17 months ago
26 votes 5 answers20k views
How do VendorInvestigate and PeptideMeter compare on the same a GLP-1 receptor agonist batch?

For reference: VendorInvestigate · PeptideMeter · a GLP-1 receptor agonist. I am trying to choose between two options that are usually discussed as though only one…

janoshik
janoshik

Janoshik Analytical, an independent third-party testing laboratory widely used by this community for HPLC purity, identity and quantified content…

34 questions
medutest
medutest

Medutest, one of four independent testing and verification services referenced throughout this site. Use this tag for its methods, its report…

14 questions
batch-testing
batch-testing

Testing at the batch or lot level: sampling plans, how many vials from a lot need testing to say anything about the lot, and the difference…

865 questions
asked by swab_stopper 16k · 9 months ago
26 votes 5 answers19k views
How do I read an impurity table on a cagrilintide certificate against the 95.2% headline?

What I have: cagrilintide · 95.2%. I can do the algebra. I am not confident about the conversion factors. If there is a standard way to lay this out, I would rather…

purity
purity

Purity as chromatographic area per cent - the fraction of detected material that is your target peak. It says nothing about how much material is…

788 questions
coa
coa

Certificates of analysis: what fields a useful one carries, how to tell a real analytical report from a marketing document, batch and lot…

749 questions
hplc
hplc

Reverse-phase high-performance liquid chromatography, the workhorse purity method. Column chemistry, mobile-phase choice, gradient slope,…

466 questions
asked by charge_state_3 39k · 14 months ago