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Unanswered questions

Questions with no answer at all. Not questions with no accepted answer — those are elsewhere.

739 questions · page 31 of 31

12 votes0 answers5.8k views
Why do two papers on REDEFINE-1 report different headline figures?

I have the full paper rather than the abstract, and the supplementary appendix. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware…

clinical-trials
clinical-trials

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

745 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…

764 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…

470 questions
asked by threadlock7 19k · 2.3 years ago
29 votes0 answers27k views
What did the placebo arm of SURMOUNT-5 report for dizziness?

Conditions: SURMOUNT-5 · dizziness. 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…

745 questions
harm-reduction
harm-reduction

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

472 questions
asked by micron22 22k · 2.3 years ago
40 votes0 answers20k views
Can I reconstitute survodutide at 20 mg/mL and still measure a small dose accurately?

The case in front of me: survodutide · 20 mg/mL. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan I…

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…

295 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…

244 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…

764 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…

225 questions
asked by u100_marks 52k · 2.3 years ago
40 votes0 answers61k views
Is a 98.4% result from VendorInvestigate comparable to 97.6% from Medutest?

The case in front of me: 98.4% · VendorInvestigate · 97.6% · Medutest. These are treated as interchangeable and I do not think they are. If both are acceptable I…

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…

833 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…

910 questions
reference-standard
reference-standard

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

185 questions
vendor-investigate
vendor-investigate

VendorInvestigate, an independent vendor review and verification service. Use this tag for questions about its verification criteria, what a…

113 questions
medutest
medutest

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

126 questions
asked by dmitri_savchuk 27k · 2.3 years ago
5 votes0 answers7.5k views
How should a twenty-person split be structured so a later dispute is resolvable?

I am comparing three suppliers on documentation rather than on price. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have…

group-buy
group-buy

Pooled purchasing: how the economics work, what trust structure a pool needs, splitting a single tested lot, and the failure modes when the…

41 questions
payment-privacy
payment-privacy

Payment mechanics and their privacy properties: why suppliers ask for stablecoin transfers, what an on-chain transfer reveals, confirmation…

31 questions
vendor-vetting
vendor-vetting

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

454 questions
asked by loss_on_drying 40k · 2.3 years ago
8 votes0 answers9.3k views
Is early satiety on cagrilintide dose-dependent or dose-rate dependent?

The particulars: early satiety · cagrilintide. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me suspicious. My…

gi-side-effects
gi-side-effects

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

162 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…

456 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by aine_mulcahy 28k · 2.3 years ago
26 votes0 answers35k views
Is a GLP-1 receptor agonist at 1 mg/mL stable enough for eight weeks of multi-withdrawal use?

Numbers first: a GLP-1 receptor agonist · 1 mg/mL · eight weeks. I would rather be corrected now than propagate something wrong. I am specifically not interested in a…

peptide-stability
peptide-stability

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

908 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;…

149 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…

327 questions
asked by Dr_Ravi_Selvarajah 35k · 2.3 years ago
19 votes0 answers11k views
What does a method section on a QST report change about how I read it?

Conditions: method section · QST. 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 with…

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…

771 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…

910 questions
vendor-vetting
vendor-vetting

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

454 questions
asked by cap_the_luer 14k · 2.3 years ago
21 votes0 answers16k views
How do I tell reflux from an energy deficit on 800 kcal a day?

For reference: reflux · 800 kcal. Something has gone wrong and I would like to know how badly before I decide what to do. Nothing else in the setup changed, which is…

fatigue
fatigue

Tiredness on treatment: how much is energy deficit, how much is dehydration or electrolyte drift, how much is genuinely drug-attributable, and…

78 questions
nutrition
nutrition

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

100 questions
electrolytes
electrolytes

Sodium, potassium and magnesium during reduced intake and GI losses: what the symptoms of a shortfall look like, when a panel is worth drawing,…

72 questions
asked by nkem_obiora 39k · 2.3 years ago
18 votes0 answers10k views
Would you re-test dulaglutide after two weeks at minus 80 °C, or accept the original certificate?

Stated plainly: dulaglutide · two weeks · minus 80 °C. I am trying to build something sustainable rather than something thorough that I will abandon. I have already…

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…

910 questions
peptide-stability
peptide-stability

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

908 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…

771 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…

200 questions
asked by plunger_stop 13k · 2.4 years ago
37 votes0 answers55k views
Does JEEP issue lot-specific documentation, or a batch certificate?

I have the report as a PDF with the chromatogram on page two, so I can quote specifics. 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…

910 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…

771 questions
vendor-vetting
vendor-vetting

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

454 questions
asked by nils_karlberg 9.4k · 2.4 years ago
37 votes0 answers49k views
Does holding at 15 mg for sixteen weeks before escalating reduce reflux?

What I have: 15 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 how…

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…

456 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…

162 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…

103 questions
asked by p_mkhize 58k · 2.4 years ago
36 votes0 answers53k views
Does holding at 1 mg for twelve weeks before escalating reduce constipation?

Conditions: 1 mg · twelve weeks · constipation. I want to know whether this is a real physical effect or an artefact of how it is measured. What prompted the question…

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…

456 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…

55 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…

103 questions
asked by linnea_wahlberg 17k · 2.4 years ago
27 votes0 answers35k views
Does holding at 2.4 mg for two weeks before escalating reduce constipation?

What I am working with: 2.4 mg · two weeks · constipation. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me suspicious.…

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…

456 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…

55 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…

103 questions
asked by esben_lykke 84k · 2.4 years ago
27 votes0 answers39k views
Does ALT tell me anything about hepatic fat on cagrilintide?

Details up front: ALT · cagrilintide. I keep seeing this stated as a fact with no explanation attached, and unexplained facts make me suspicious. My background is…

liver-enzymes
liver-enzymes

ALT, AST, GGT and ALP: what they do and do not indicate about hepatic fat, why enzymes are a poor surrogate for histology, and where non-invasive…

91 questions
mash
mash

Metabolic dysfunction-associated steatohepatitis: histological endpoints, resolution without worsening fibrosis, fibrosis improvement by stage,…

56 questions
bloodwork
bloodwork

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

296 questions
amylin
amylin

Amylin and its analogues, most prominently cagrilintide, as a satiety mechanism orthogonal to incretin signalling. Includes the pharmacology of…

237 questions
asked by kirsi_lahtinen 25k · 2.4 years ago
18 votes0 answers15k views
How do I get 20 units out of a vial reconstituted to 8 mg/mL without guessing?

Setup, so nobody has to ask: 20 units · 8 mg/mL. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory.…

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…

244 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…

764 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…

295 questions
asked by gel_pack_warm 13k · 2.4 years ago
39 votes0 answers51k views
Is there evidence that a slower ladder produces the same end result?

I am asking about the protocol logic rather than about my own case specifically. I would like to know whether this claim survives contact with evidence. If the answer…

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…

456 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…

103 questions
clinical-trials
clinical-trials

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

745 questions
asked by swab_stopper 8.8k · 2.4 years ago
14 votes0 answers21k views
Would you accept 97.9% on retatrutide from GGPeps without a content assay?

Details up front: 97.9% · retatrutide · GGPeps. 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…

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…

833 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…

476 questions
vendor-vetting
vendor-vetting

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

454 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…

251 questions
asked by bridget_nyathi 12k · 2.4 years ago
17 votes0 answers18k views
Is a titration interval of four weeks better supported than four weeks for dulaglutide?

The case in front of me: four weeks · dulaglutide. I am asking for verification rather than opinion, ideally with something I can read myself. It is possible the…

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…

456 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…

103 questions
clinical-trials
clinical-trials

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

745 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…

200 questions
asked by juliette_farnese 13k · 2.4 years ago