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Newest first. 5.2k questions across 107 tags.

5.2k questions · page 111 of 217

33 votes 5 answers39k views
Is ATTAIN-1 a fair comparison of cagrilintide against its comparator arm?

Setup, so nobody has to ask: ATTAIN-1 · cagrilintide. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary sources all…

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
dulaglutide
dulaglutide

A once-weekly GLP-1 receptor agonist built on an Fc fusion rather than fatty-acid acylation. Use this tag for questions about the fusion-protein…

14 questions
asked by juan_esquivel 14k · 15 months ago
22 votes 4 answers12k views
What is the real-world lead time from Suzhou to Sweden in winter?

Setup, so nobody has to ask: Suzhou · Sweden. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

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 helena_vidmar 18k · 15 months ago
28 votes 5 answers19k views
Is a JEEP order from Shanghai likely to hold cold chain to Japan?

Details up front: JEEP · Shanghai · Japan. This is a planning question. I know what my options are; I do not know how to weigh them. What I want is the minimum viable…

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 priya_menon 11k · 15 months ago
10 votes 5 answers11k views
What does REDEFINE-1 report at the 40 mg dose level?

What I have: REDEFINE-1 · 40 mg. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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 haze_check 17k · 15 months ago
15 votes 5 answers13k views
How much protein in grams do I need at 68 kg on 1,200 kcal a day?

Details up front: 68 kg · 1,200 kcal. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is…

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 lane_transit 42k · 15 months ago
32 votes4 answers11k views
Does holding at 2 mg for sixteen weeks before escalating reduce reflux?

Details up front: 2 mg · sixteen weeks · reflux. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know…

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
constipation
constipation

Slowed transit as a consequence of delayed gastric emptying and reduced intake: incidence figures, fibre and hydration evidence, and why it often…

14 questions
asked by threadlock7 14k · 15 months ago
15 votes 4 answers7k views
How do I set an accept/reject threshold before I see the result?

This is my second independent submission on material from the same supplier. This is a planning question. I know what my options are; I do not know how to weigh them.…

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
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
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 label_claim 11k · 15 months ago
13 votes5 answers8.5k views
What does PIONEER-4 tell me about nausea at the 50 mg dose?

Numbers first: PIONEER-4 · nausea · 50 mg. I can parse the result. I am less sure what it licenses me to conclude. I have deliberately not looked at anyone else’s…

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 meniscus_film 34k · 15 months ago
25 votes 5 answers32k views
Does WWB issue lot-specific documentation, or a batch certificate?

This is my second independent submission on material from the same supplier. I can parse the result. I am less sure what it licenses me to conclude. I have…

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
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
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 ravenna_pace 13k · 15 months ago
6 votes 5 answers17k views
Is there a pharmacokinetic case for moving a GLP-1 receptor agonist injection day by five days?

What I have: a GLP-1 receptor agonist · five days. I can predict the outcome but I cannot explain it, which means I will get the next case wrong. I would like to know…

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
glp1-mechanism
glp1-mechanism

Receptor-level pharmacology: GLP-1R as a class B GPCR, cAMP and PKA signalling, biased agonism, internalisation and resensitisation, and the…

175 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 dmitri_savchuk 17k · 15 months ago
30 votes5 answers16k views
Why did two KP lots of orforglipron differ on content assay?

Numbers first: KP · orforglipron. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and eliminated…

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 fib4_reader 35k · 15 months ago
28 votes 5 answers22k views
Why did two QST lots of oral semaglutide differ on content assay?

Conditions: QST · oral semaglutide. I have two candidate explanations and no way to distinguish them. The same procedure has worked without incident several times…

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 aine_mulcahy 35k · 15 months ago
22 votes0 answers17k views
What fraction of loss on survodutide is lean mass according to STEP 1?

The case in front of me: survodutide · STEP 1. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single…

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 nynke_dekker 18k · 15 months ago
20 votes 5 answers17k views
What does a 99.4% purity with a date of analysis attached let me conclude?

Concretely: 99.4% · date of analysis. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single result,…

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 rhian_prydderch 44k · 15 months ago
29 votes0 answers17k views
Is a chromatogram from QYB sufficient basis to skip independent testing?

The case in front of me: chromatogram · QYB. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like…

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
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
asked by Dr_Ravi_Selvarajah 42k · 15 months ago
7 votes 5 answers12k views
Is a 25G drawing needle the right choice for drawing tirzepatide at 10 mg/mL?

Conditions: a 25G drawing needle · tirzepatide · 10 mg/mL. I would like the axes of comparison first and the recommendation second. I have tried the first option and…

needle-gauge
needle-gauge

Gauge and length selection, the trade-off between draw time and tissue trauma, coring risk with larger-bore needles, and why a fixed-needle…

85 questions
injection-technique
injection-technique

Technique questions: angle, pinch versus flat, aspiration, injection speed, air bubbles, and the handling steps that determine whether you deliver…

90 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
asked by cal_hennessy 14k · 15 months ago
28 votes 5 answers28k views
Does the REDEFINE-1 population resemble anyone asking about liraglutide here?

Conditions: REDEFINE-1 · liraglutide. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a single result,…

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
cagrisema
cagrisema

A fixed-ratio combination of cagrilintide, a long-acting amylin analogue, with semaglutide, studied in the REDEFINE programme. Questions here…

14 questions
survodutide
survodutide

A GLP-1 and glucagon receptor dual agonist with a substantial published MASH dataset. Use this tag for its hepatic endpoints, its dose ladder, and…

14 questions
asked by seven_day_half 16k · 15 months ago
35 votes 2 answers24k views
How much protein in grams do I need at 88 kg on 1,100 kcal a day?

Concretely: 88 kg · 1,100 kcal. Please show the division. I want to check my own against yours. I would like the general form as well as the specific number, so I can…

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 anders_vestby 17k · 15 months ago
4 votes 5 answers4.7k views
Does a DEXA repeated every six weeks give me an usable lean-mass trend?

I would like to know what to measure as much as what to do. I would like the axes of comparison first and the recommendation second. I have tried the first option and…

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
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
asked by day_seven_trough 11k · 15 months ago
21 votes5 answers15k views
How do I convert the REDEFINE-1 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 vial_five 15k · 15 months ago
23 votes 3 answers25k views
Is tirzepatide at 2.5 mg/mL stable enough for four weeks of multi-withdrawal use?

For reference: tirzepatide · 2.5 mg/mL · four weeks. Somebody stated this to me confidently and I would like to check it before repeating it. I would accept a…

peptide-stability
peptide-stability

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

832 questions
bacteriostatic-water
bacteriostatic-water

Water for injection containing roughly 0.9 per cent benzyl alcohol as a bacteriostatic agent. It suppresses growth in a multiple-withdrawal vial;…

112 questions
shelf-life
shelf-life

How long a preparation remains within specification: labelled expiry for a sealed lyophilised vial, beyond-use dating after reconstitution, and…

301 questions
asked by tess_amankwah 48k · 15 months ago
15 votes0 answers6.9k views
What is the arithmetic to convert 4 mg in 2.5 mL into units on a U-100 scale?

The specifics, since they change the answer: 4 mg · 2.5 mL. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers…

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 cake_collapsed 13k · 15 months ago
30 votes 2 answers32k views
What is a sensible monitoring routine for oral semaglutide over ten weeks?

For reference: oral semaglutide · ten weeks. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit stopping…

bloodwork
bloodwork

Laboratory monitoring: which panels are worth ordering, sensible intervals, reference-range versus optimal-range arguments, and how to read a…

284 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
plateau
plateau

A stall in progress: distinguishing adaptive thermogenesis from measurement error from adherence drift, how long to observe before changing…

35 questions
asked by marta_szymanska 17k · 15 months ago
26 votes 5 answers26k views
What is the reported incidence of constipation on mazdutide in REDEFINE-1?

What I am working with: constipation · mazdutide · REDEFINE-1. I would like help reading this properly rather than being told what conclusion to reach. I have the…

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 tare_and_weigh 18k · 15 months ago