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5.2k questions · page 49 of 217

19 votes 4 answers11k views
How much protein in grams do I need at 103 kg on 800 kcal a day?

For reference: 103 kg · 800 kcal. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a factor of…

protein-intake
protein-intake

Protein targets in grams per kilogram, per-meal distribution and the leucine threshold, and the evidence for a higher intake specifically during…

53 questions
nutrition
nutrition

Eating on a suppressed appetite: hitting nutritional targets inside a small energy budget, micronutrient risk, meal structure, and what the trial…

92 questions
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
asked by rune_thoresen 14k · 6 months ago
17 votes3 answers5.5k views
Does SOUL show oral semaglutide is cardiovascularly equivalent to the injectable?

SOUL tested oral semaglutide 14 mg daily in people with type 2 diabetes and either atherosclerotic cardiovascular disease or chronic kidney disease, and reported a…

oral-glp1
oral-glp1

Oral routes for GLP-1 receptor agonism: peptide formulations rescued by absorption enhancers such as SNAC, and true small molecules that need no…

14 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
clinical-trials
clinical-trials

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

913 questions
asked by dead_volume 49k · 6 months ago
25 votes 2 answers16k views
Is TRIUMPH-1 a fair comparison of survodutide against its comparator arm?

The specifics, since they change the answer: TRIUMPH-1 · survodutide. Somebody stated this to me confidently and I would like to check it before repeating it. I would…

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
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
asked by g_paskevicius 44k · 6 months ago
28 votes 2 answers15k views
Is reflux on ecnoglutide dose-dependent or dose-rate dependent?

The particulars: reflux · ecnoglutide. I would like the mechanism, because I want to be able to reason about the cases nobody has written about. I have tried to…

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
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
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
asked by mala_venkatesh 21k · 6 months ago
25 votes 1 answer8.6k views
Is a slightly shorter cake height across a five-vial order a problem?

I have a logging thermometer, a box of insulin syringes and no illusions about my worktop being sterile. An unexpected observation, and I would like a differential…

vial-inspection
vial-inspection

What you can learn by looking: cake morphology, meniscus films, fibres versus stopper fragments versus true particulates, clarity after…

66 questions
lyophilisation
lyophilisation

Freeze-drying: primary and secondary drying, collapse temperature, the role of bulking agents and cryoprotectants such as mannitol and trehalose,…

17 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 one_ml_bac 12k · 6 months ago
20 votes 5 answers8.5k views
Does holding at 15 mg for three weeks before escalating reduce injection-site erythema?

For reference: 15 mg · three weeks · injection-site erythema. I would like the mechanism, because I want to be able to reason about the cases nobody has written…

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 tess_amankwah 48k · 6 months ago
23 votes4 answers11k views
If a retatrutide dose is missed by fourteen days, does the ladder reset?

What I am working with: retatrutide · fourteen days. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the…

missed-dose
missed-dose

What the label instructions for a missed weekly dose are, why they differ between agents, and what the pharmacokinetics say about drift in an…

41 questions
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
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 grainne_ahearn 13k · 7 months ago
27 votes 5 answers6.6k views
What is the real-world lead time from Nantong to Canada in winter?

What I am working with: Nantong · Canada. I would like help reading this properly rather than being told what conclusion to reach. I have the full report including…

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 area_percent 13k · 7 months ago
10 votes0 answers5.4k views
Can I reconstitute dulaglutide at 8 mg/mL and still measure a small dose accurately?

Stated plainly: dulaglutide · 8 mg/mL. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my tolerance…

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
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
asked by dana_wexler 15k · 7 months ago
10 votes 3 answers6.2k views
Can I reconstitute dulaglutide at 2 mg/mL and still measure a small dose accurately?

Stated plainly: dulaglutide · 2 mg/mL. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my tolerance…

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
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
asked by Dr_Ingrid_Baumgartner 39k · 7 months ago
20 votes 5 answers11k views
How much of the gross mass of a 60 mg cagrilintide vial is actually peptide?

Setup, so nobody has to ask: 60 mg · cagrilintide. I have worked this out and I would like someone to find the error, because I suspect there is one. My working so…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

39 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

87 questions
asked by seamus_brady 17k · 7 months ago
5 votes 5 answers10k views
How many freeze-thaw cycles will dulaglutide at 3.33 mg/mL tolerate?

What I am working with: dulaglutide · 3.33 mg/mL. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory.…

freeze-thaw
freeze-thaw

What repeated freezing does to a peptide in solution: ice-crystal shear at the growing front, freeze-concentration of solutes, pH shifts as buffer…

55 questions
peptide-stability
peptide-stability

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

832 questions
storage
storage

Storage conditions and their evidence base: minus twenty degrees for powder, refrigerated for solution, protection from light, and what the…

646 questions
asked by area_percent 13k · 7 months ago
21 votes 5 answers13k views
How do I convert a mg/kg figure from a trial into a fixed dose?

I have photographs before and after reconstitution if the visual detail matters. I have worked this out and I would like someone to find the error, because I suspect…

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
clinical-trials
clinical-trials

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

913 questions
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
asked by esben_lykke 15k · 7 months ago
22 votes3 answers16k views
Why did two JEEP lots of orforglipron differ on content assay?

What I have: JEEP · orforglipron. Before I write this off, I want to check whether it is a known failure mode. I have the lot number, the certificate and the date,…

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 halvard_ness 42k · 7 months ago
23 votes5 answers7.8k views
Is 99.1% a realistic purity ceiling for retatrutide given its chain length?

What I have: 99.1% · retatrutide. 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
hplc
hplc

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

466 questions
peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

83 questions
asked by s_bhattacharya 42k · 7 months ago
6 votes 5 answers3.2k views
What does STEP 3 report at the 10 mg dose level?

Details up front: STEP 3 · 10 mg. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to disagree,…

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
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
asked by sasha_ferreira 15k · 7 months ago
24 votes0 answers13k views
How much of the gross mass of a 40 mg liraglutide vial is actually peptide?

Concretely: 40 mg · liraglutide. I want the working, not the result — I need to be able to redo it with different numbers. I care about the precision as well as the…

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
water-content
water-content

Residual moisture in a lyophilised solid, measured by Karl Fischer titration or loss on drying. It drives both the mass balance on a content assay…

39 questions
acetate-content
acetate-content

Counter-ion content, most often acetate or trifluoroacetate, and why it matters: the counter-ion and residual water are part of the gross mass you…

87 questions
asked by coring_risk 17k · 7 months ago
7 votes0 answers2.6k views
What does a list of related substances on a GL Biochem report change about how I read it?

The case in front of me: list of related substances · GL Biochem. The figures are clear enough; the question is what they mean and what they do not. I can supply the…

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
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
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 retest_please 13k · 7 months ago
18 votes 5 answers14k views
Does early satiety at week two of orforglipron usually resolve without a dose change?

Conditions: early satiety · two · orforglipron. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made one…

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
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
asked by ravenna_pace 13k · 7 months ago
20 votes 3 answers8.2k views
Does the SURPASS-3 population resemble anyone asking about oral semaglutide here?

Conditions: SURPASS-3 · oral semaglutide. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics…

clinical-trials
clinical-trials

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

913 questions
harm-reduction
harm-reduction

Reducing avoidable risk where a decision has already been made: independent verification before use, sterility practice, dose arithmetic checked…

445 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 bufferline42 49k · 7 months ago
11 votes 5 answers8.6k views
What fraction of loss on ecnoglutide is lean mass according to ESSENCE?

The case in front of me: ecnoglutide · ESSENCE. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

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 rae_oyelowo 21k · 7 months ago
28 votes 5 answers21k views
Is a 97.1% result from PeptideMeter comparable to 95.2% from Janoshik?

The specifics, since they change the answer: 97.1% · PeptideMeter · 95.2% · Janoshik. I am trying to choose between two options that are usually discussed as though…

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
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
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 nkem_obiora 46k · 7 months ago
6 votes5 answers7.9k views
What did the placebo arm of ESSENCE report for early satiety?

The particulars: ESSENCE · early satiety. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I am reasonably…

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 cal_hennessy 14k · 7 months ago
25 votes 4 answers15k views
What does PIONEER-4 tell me about headache at the 2 mg dose?

The specifics, since they change the answer: PIONEER-4 · headache · 2 mg. I have the document in front of me and I can read the numbers. What I cannot do is interpret…

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
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
asked by ravenna_pace 13k · 7 months ago