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5.2k questions · page 166 of 217

26 votes5 answers42k views
What is the reported incidence of vomiting on tirzepatide in SURMOUNT-1?

Details up front: vomiting · tirzepatide · SURMOUNT-1. This is presented as though it settles something, and I am not convinced it does. I have two documents that…

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
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 ruaidhri_o_shea 25k · 22 months ago
32 votes 5 answers31k views
What is the real-world lead time from Wuxi to Singapore in winter?

Conditions: Wuxi · Singapore. This is presented as though it settles something, and I am not convinced it does. I have two documents that appear to disagree, which 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
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
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
asked by Dr_Nadia_Farsi 104k · 22 months ago
9 votes2 answers13k views
Is there any published stability data for a GLP-1 receptor agonist at room temperature?

What I have: a GLP-1 receptor agonist · room temperature. 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
storage
storage

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

701 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_and_wait 13k · 22 months ago
5 votes3 answers7.6k views
Is a 97.9% result from VendorInvestigate comparable to 97.1% from Janoshik?

Conditions: 97.9% · VendorInvestigate · 97.1% · Janoshik. These are treated as interchangeable and I do not think they are. If both are acceptable I would like to…

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
janoshik
janoshik

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

139 questions
asked by thermal_mass 13k · 22 months ago
27 votes 5 answers51k views
How do I compute the +5 charge state m/z for a peptide of 4813.5 Da?

The case in front of me: +5 · 4813.5 Da. 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…

mass-spec
mass-spec

Mass spectrometry for identity confirmation: electrospray ionisation, multiple charge states, monoisotopic versus average mass, deconvolution, and…

52 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
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
asked by leah_ferrers 12k · 22 months ago
11 votes0 answers4.2k views
Would you re-test semaglutide after twelve weeks at 4 °C, or accept the original certificate?

The case in front of me: semaglutide · twelve weeks · 4 °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
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 zeynep_arslan 16k · 22 months ago
25 votes 5 answers31k views
Is a domestic freezer good enough for storing reconstituted oral semaglutide?

Setup, so nobody has to ask: a domestic freezer · oral semaglutide. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will…

storage
storage

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

701 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
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
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…

219 questions
asked by ilaria_bertone 33k · 22 months ago
34 votes 5 answers38k views
What is the dead-space loss per draw with a 30G needle at 3.33 mg/mL?

The case in front of me: a 30G needle · 3.33 mg/mL. I want the working, not the result — I need to be able to redo it with different numbers. I care about the…

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
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
asked by unit_math 6.2k · 22 months ago
8 votes 5 answers26k views
What does a payer want to see before approving semaglutide?

This is a United States plan; I appreciate the answer is jurisdiction-specific. I am trying to do this correctly the first time rather than learn it by getting it…

prior-authorization
prior-authorization

Prior authorisation mechanics: medical-necessity criteria, documenting a lifestyle-intervention requirement, step therapy, and the…

19 questions
insurance
insurance

Coverage: formulary tiers, exclusion versus non-coverage, the difference a diabetes indication makes, employer carve-outs, and what an appeal…

35 questions
t2dm
t2dm

Type 2 diabetes: glycaemic endpoints, the SURPASS and SUSTAIN programmes, dose ranges licensed for diabetes versus obesity, and interaction with…

22 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 Dr_Elias_Weiss 25k · 22 months ago
36 votes5 answers36k views
What is the reported incidence of nausea on retatrutide in TRIUMPH-3?

Conditions: nausea · retatrutide · TRIUMPH-3. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the…

nausea
nausea

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

55 questions
clinical-trials
clinical-trials

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

745 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 fib4_reader 24k · 22 months ago
26 votes5 answers18k views
How does liraglutide behave on a wide-pore C18 column compared to survodutide?

The specifics, since they change the answer: liraglutide · a wide-pore C18 column · survodutide. I am trying to choose between two options that are usually discussed…

hplc
hplc

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

503 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…

833 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
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
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 coring_risk 27k · 22 months ago
28 votes 2 answers35k views
What did the placebo arm of STEP 1 report for headache?

The specifics, since they change the answer: STEP 1 · headache. I have the document in front of me and I can read the numbers. What I cannot do is interpret them. I…

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 leonid_marchuk 19k · 22 months ago
30 votes 3 answers35k views
How much product does syringe dead space actually cost me? Fixed-needle versus luer-lock, in µL and mg

I have been using 1 mL luer-lock syringes with detachable 27 G needles because that is what came in the box, and someone told me offhand that I am "wasting a third of…

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
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
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
asked by sample_id 17k · 22 months ago
35 votes 5 answers50k views
How do I convert the SURMOUNT-5 hazard ratio into an absolute risk reduction?

I have three data points across nine months, which I hope is enough to see a trend. I would like the arithmetic checked rather than the conclusion asserted. I have…

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…

68 questions
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
asked by area_percent 9.9k · 22 months ago
9 votes 5 answers30k views
Is potassium worth drawing at baseline before starting semaglutide?

The particulars: potassium · semaglutide. I am at the decision point and I would rather think it through than improvise. I would rather spend money on measurement…

bloodwork
bloodwork

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

296 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
a1c
a1c

Glycated haemoglobin as a ninety-day glycaemic average: what a change of half a point means, why it lags, and the conditions under which it…

122 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
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 nils_karlberg 9.4k · 22 months ago
53 votes 3 answers25k views
How much of the fatigue is actually drug-attributable, and what did the placebo arms report?

I am five months in, down 16 kg, and flattened. Not sleepy, exactly. More that everything costs more than it used to: stairs, conversations, training sessions I used…

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
clinical-trials
clinical-trials

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

745 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 h_villanueva 70k · 22 months ago
28 votes0 answers28k views
Is there any published stability data for liraglutide at 40 °C?

The specifics, since they change the answer: liraglutide · 40 °C. I would like to know whether this claim survives contact with evidence. If the answer is "nobody has…

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
clinical-trials
clinical-trials

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

745 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 j_wierzbicki 69k · 22 months ago
17 votes 5 answers16k views
What should be in place before a first liraglutide vial arrives from Xianning?

What I have: liraglutide · Xianning. I am at the decision point and I would rather think it through than improvise. I would rather spend money on measurement than on…

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
research-use-only
research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

95 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…

142 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 fibre_or_fragment 13k · 22 months ago
41 votes5 answers49k views
What did the placebo arm of STEP 1 report for hair thinning?

The particulars: STEP 1 · hair thinning. 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
hair-loss
hair-loss

Telogen effluvium following rapid weight loss versus a drug-attributable effect: the timing signature that distinguishes them, protein and…

50 questions
asked by ines_delacruz 16k · 22 months ago
25 votes0 answers18k views
How is a beyond-use date set for compounded orforglipron in phosphate-buffered diluent?

Stated plainly: orforglipron · phosphate-buffered diluent. Everything I have found on this is either a forum aside or a product page, neither of which I trust. I am…

compounding
compounding

Compounded preparations: what a 503A and a 503B facility may legally prepare and when, base versus salt forms, beyond-use dating under USP…

61 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
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
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…

219 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
asked by thermal_mass 13k · 22 months ago
2 votes 5 answers15k views
How do I read a retatrutide chromatogram from Medutest beyond the headline number?

The case in front of me: retatrutide · Medutest. I have read the primary source rather than the summary, which has left me with more questions. I understand the…

hplc
hplc

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

503 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…

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
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
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 mz_4113 101k · 22 months ago
11 votes 5 answers9.6k views
What should be in place before a first orforglipron vial arrives from Zhuhai?

Stated plainly: orforglipron · Zhuhai. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided the broad…

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
research-use-only
research-use-only

What "for research use only" means as a legal and practical designation: not approved for human use, no pharmacopoeial release testing, no…

95 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…

142 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…

219 questions
asked by fibre_or_fragment 13k · 22 months ago
5 votes0 answers3.2k views
What is a sensible monitoring routine for retatrutide over two weeks?

Details up front: retatrutide · two weeks. I am trying to build something sustainable rather than something thorough that I will abandon. I have already decided the…

bloodwork
bloodwork

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

296 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
plateau
plateau

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

36 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 coring_risk 27k · 22 months ago
18 votes5 answers26k views
Does creatinine tell me anything about hepatic fat on cagrilintide?

What I have: creatinine · cagrilintide. The empirical answer seems settled. The explanation does not. If the honest answer is that nobody knows, I would rather hear…

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
kidney-function
kidney-function

eGFR, creatinine, cystatin C and albuminuria: the acute haemodynamic dip that is not injury, the renal outcome data from the FLOW programme, and…

141 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 olu_babatunde 6.2k · 22 months ago