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5.2k questions · page 191 of 217

4 votes 5 answers18k views
What is the reported incidence of dizziness on tirzepatide in SURMOUNT-5?

The specifics, since they change the answer: dizziness · tirzepatide · SURMOUNT-5. I want to understand what this actually establishes, as opposed to what it is being…

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
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…

370 questions
asked by mg_per_ml 15k · 2.1 years ago
9 votes 5 answers15k views
Is 50 mg in 5 mL of phosphate-buffered diluent a sensible presentation for dulaglutide?

The particulars: 50 mg · 5 mL · phosphate-buffered diluent · dulaglutide. I would like to define my thresholds before I have a result, for obvious reasons. I want a…

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
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,…

313 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
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 Dr_Aoife_Brennan 20k · 2.1 years ago
35 votes 5 answers70k views
How long does a Wuxi to the Netherlands lane usually take with tracking?

Setup, so nobody has to ask: Wuxi · the Netherlands. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is…

international-shipping
international-shipping

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

471 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…

196 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…

578 questions
asked by net_peptide 12k · 2.1 years ago
32 votes 5 answers46k views
What does a 99.1% purity with a chromatogram attached let me conclude?

The particulars: 99.1% · chromatogram. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am…

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
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
hplc
hplc

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

503 questions
asked by eighty_six_hours 20k · 2.1 years ago
4 votes 2 answers4.6k views
What does a 95.2% purity with a chromatogram attached let me conclude?

The specifics, since they change the answer: 95.2% · chromatogram. I want to understand what this actually establishes, as opposed to what it is being used to imply.…

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
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
hplc
hplc

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

503 questions
asked by ines_delacruz 16k · 2.1 years ago
21 votes4 answers33k views
What is the thermal exposure on a Xi’an to Finland lane in summer?

Concretely: Xi’an · Finland. I want to understand what this actually establishes, as opposed to what it is being used to imply. My concern is that I am being invited…

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…

578 questions
international-shipping
international-shipping

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

471 questions
storage
storage

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

701 questions
asked by lucia_marchetti 19k · 2.1 years ago
20 votes 5 answers29k views
Is room temperature an acceptable storage condition for lyophilised cagrilintide?

Stated plainly: room temperature · cagrilintide. This is asserted often enough that I assumed it was established, and then I went looking for the source. I have…

storage
storage

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

701 questions
peptide-stability
peptide-stability

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

908 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
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 leah_ferrers 12k · 2.1 years ago
5 votes0 answers4.4k views
How long does retatrutide stay within specification at 30 °C once reconstituted?

Stated plainly: retatrutide · 30 °C. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory. What I have…

peptide-stability
peptide-stability

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

908 questions
storage
storage

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

701 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
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 loss_on_drying 40k · 2.1 years ago
32 votes 5 answers38k views
Would you re-test cagrilintide after sixteen weeks at room temperature, or accept the original certificate?

Setup, so nobody has to ask: cagrilintide · sixteen weeks · room temperature. I would rather over-plan the first cycle and simplify later. I am prepared to do the…

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
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 two_point_four 8.9k · 2.1 years ago
21 votes0 answers26k views
What is the reported incidence of vomiting at the top studied dose?

It has now persisted for three weeks, which is what moved this from tolerable to worth asking about. This is presented as though it settles something, and I am not…

vomiting
vomiting

Emesis as a reported adverse event: trial incidence, its relationship to dose escalation rate, dehydration risk, and when it stops being a…

57 questions
clinical-trials
clinical-trials

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

745 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
asked by wren_calloway 23k · 2.1 years ago
19 votes5 answers46k views
Does a large published testing history at SWB imply lot consistency?

This is my second independent submission on material from the same supplier. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware…

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
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
asked by Dr_Ravi_Selvarajah 35k · 2.1 years ago
18 votes5 answers19k views
Is constipation on liraglutide dose-dependent or dose-rate dependent?

What I have: constipation · liraglutide. This is one of those things that everyone repeats and nobody derives. This matters practically, not just academically,…

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
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
liraglutide
liraglutide

A once-daily GLP-1 receptor agonist and the compound that established the class. Still relevant for its shorter half-life, its paediatric and…

235 questions
asked by Dr_Fatima_Belkacem 18k · 2.1 years ago
36 votes0 answers22k views
Is a 97.6% result from VendorInvestigate comparable to 96.8% from PeptideMeter?

The case in front of me: 97.6% · VendorInvestigate · 96.8% · PeptideMeter. 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
peptidemeter
peptidemeter

PeptideMeter, an independent peptide analytics and vendor-rating service. Use this tag for its published datasets, its rating methodology, and how…

107 questions
asked by ruaidhri_o_shea 25k · 2.1 years ago
22 votes 3 answers21k views
Does swabbing a stopper with 70 % IPA do anything, and how many times can one stopper be pierced before it stops sealing?

I have been treating the vial stopper as a black box and I would like to stop. Two specific things. Swabbing. Everyone says wipe the stopper with 70 % isopropanol.…

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…

142 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…

96 questions
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…

91 questions
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
asked by void_volume 9.5k · 2.1 years ago
5 votes 5 answers12k views
Would you re-test survodutide after twelve weeks at 2–8 °C, or accept the original certificate?

The case in front of me: survodutide · twelve weeks · 2–8 °C. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow…

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
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 tabular_nums 71k · 2.1 years ago
40 votes 5 answers66k views
How many weeks to steady state for ecnoglutide on a weekly schedule?

The receptor pharmacology I can follow; the in vivo translation is where I lose the thread. I want the working, not the result — I need to be able to redo it with…

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…

132 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
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
ecnoglutide
ecnoglutide

A long-acting GLP-1 receptor agonist with a cAMP-biased signalling profile. A niche tag, mostly used for mechanism questions about biased agonism…

223 questions
asked by liam_bracken 6.9k · 2.1 years ago
27 votes 5 answers36k views
Is a Homopeptide order from Zhuhai likely to hold cold chain to Singapore?

Details up front: Homopeptide · Zhuhai · Singapore. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan…

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…

578 questions
international-shipping
international-shipping

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

471 questions
vendor-comparison
vendor-comparison

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

388 questions
asked by second_lot 9.4k · 2.1 years ago
14 votes 5 answers34k views
What did the placebo arm of ATTAIN-1 report for early satiety?

For reference: ATTAIN-1 · 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…

745 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
asked by kofi_mensah 18k · 2.1 years ago
12 votes5 answers21k views
Is 40 °C an acceptable storage condition for lyophilised semaglutide?

The particulars: 40 °C · semaglutide. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has tested that", I would like…

storage
storage

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

701 questions
peptide-stability
peptide-stability

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

908 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
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 seamus_brady 15k · 2.1 years ago
14 votes0 answers16k views
Is an 18G drawing needle the right choice for drawing semaglutide at 20 mg/mL?

The specifics, since they change the answer: an 18G drawing needle · semaglutide · 20 mg/mL. I am trying to choose between two options that are usually discussed as…

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…

91 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…

96 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…

117 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 tare_weight 60k · 2.1 years ago
8 votes 5 answers19k views
Why does dimerisation accelerate at 4 °C rather than proceeding linearly?

What I am working with: dimerisation · 4 °C. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I would rather…

peptide-stability
peptide-stability

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

908 questions
storage
storage

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

701 questions
hplc
hplc

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

503 questions
asked by deamidation_watch 45k · 2.1 years ago
5 votes 5 answers25k views
Why do two papers on SELECT report different headline figures?

My laboratory results are from the same laboratory each time, drawn fasting, which I gather matters. The empirical answer seems settled. The explanation does not. If…

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 forty_two_c 66k · 2.1 years ago
31 votes 4 answers30k views
What does SUSTAIN-6 tell me about reflux at the 2 mg dose?

Setup, so nobody has to ask: SUSTAIN-6 · reflux · 2 mg. I have read the primary source rather than the summary, which has left me with more questions. I understand…

clinical-trials
clinical-trials

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

745 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
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
asked by ines_brandt 113k · 2.1 years ago
27 votes5 answers20k views
Is dulaglutide at 20 mg/mL stable enough for six weeks of multi-withdrawal use?

Setup, so nobody has to ask: dulaglutide · 20 mg/mL · six weeks. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary…

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
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 nominal_ten 12k · 2.1 years ago