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Newest first. 5.2k questions across 107 tags.

5.2k questions · page 124 of 217

36 votes5 answers45k views
Is 1.7 mg weekly a defensible maintenance dose for dulaglutide?

What I have: 1.7 mg · dulaglutide. 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…

maintenance-dose
maintenance-dose

Staying put: the lowest dose that holds a result, the difference between the maximum studied dose and the maximum useful dose, and what the…

54 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
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 tare_weight 60k · 16 months ago
13 votes 5 answers11k views
How many units on a U-100 insulin syringe is a 2.5 mg dose at 20 mg/mL?

Details up front: a U-100 insulin syringe · 2.5 mg · 20 mg/mL. This should be a straightforward calculation and I keep getting two different answers. The numbers are…

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
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
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 forty_units 16k · 16 months ago
20 votes 5 answers9.9k views
How do I reconcile 95.2% from Janoshik with 99.4% from the supplier?

What I have: 95.2% · Janoshik · 99.4%. I have a result I cannot explain, and I would rather diagnose it than guess. I have checked the obvious explanations and…

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
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
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 cake_intact 17k · 16 months ago
30 votes 5 answers39k views
If I reconstitute a 2 mg vial with 1 mL of sterile water for injection, what concentration do I end up with?

What I have: 2 mg · 1 mL · sterile water for injection. This should be a straightforward calculation and I keep getting two different answers. The numbers are…

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
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
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
sterile-water
sterile-water

Preservative-free sterile water for injection: appropriate for a single-withdrawal presentation, a poor choice for anything you intend to open…

35 questions
asked by jana_horakova 10k · 16 months ago
32 votes5 answers46k views
Is a wine cooler good enough for storing reconstituted retatrutide?

Conditions: a wine cooler · retatrutide. 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…

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
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 bounty_hunter_q 15k · 16 months ago
20 votes 5 answers17k views
How much protein in grams do I need at 62 kg on 800 kcal a day?

Numbers first: 62 kg · 800 kcal. This should be a straightforward calculation and I keep getting two different answers. The numbers are arbitrary; the method is what…

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…

60 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
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…

127 questions
asked by area_percent 9.9k · 16 months ago
37 votes 5 answers14k views
How does semaglutide behave on a C4 column compared to mazdutide?

Concretely: semaglutide · a C4 column · mazdutide. I would like the axes of comparison first and the recommendation second. I have tried the first option and it…

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
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
mazdutide
mazdutide

A GLP-1 and glucagon receptor dual agonist developed primarily in China, with a distinct dose range and a fast-moving publication record.…

237 questions
asked by ivo_paunovic 16k · 16 months ago
2 votes5 answers12k views
What did the placebo arm of ATTAIN-1 report for vomiting?

Concretely: ATTAIN-1 · vomiting. 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, which I…

clinical-trials
clinical-trials

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

745 questions
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
asked by loss_on_drying 40k · 16 months ago
10 votes 5 answers17k views
Would you accept 96.4% on liraglutide from WXT without a content assay?

The case in front of me: 96.4% · liraglutide · WXT. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and 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
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
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 eighty_six_hours 20k · 16 months ago
27 votes5 answers36k views
How does ecnoglutide at 1 mg weekly compare on cost per milligram across routes?

The case in front of me: ecnoglutide · 1 mg. Please show the division. I want to check my own against yours. I would like the general form as well as the specific…

cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 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
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 k_szabo 27k · 16 months ago
33 votes5 answers34k views
How do I convert the PIONEER-1 hazard ratio into an absolute risk reduction?

My laboratory results are from the same laboratory each time, drawn fasting, which I gather matters. Please show the division. I want to check my own against yours. I…

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 sunniva_dahl 22k · 16 months ago
2 votes5 answers7.9k views
What is the thermal exposure on a Nantong to Australia lane in summer?

Concretely: Nantong · Australia. 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, which I…

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 cap_the_luer 14k · 16 months ago
7 votes5 answers20k views
How do I reconcile 97.1% from VendorInvestigate with 98.4% from the supplier?

The case in front of me: 97.1% · VendorInvestigate · 98.4%. I have two candidate explanations and no way to distinguish them. The same procedure has worked without…

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
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-investigate
vendor-investigate

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

113 questions
asked by imani_dube 8.9k · 16 months ago
35 votes5 answers38k views
If I reconstitute a 10 mg vial with 2.5 mL of 0.9% sodium chloride, what concentration do I end up with?

The case in front of me: 10 mg · 2.5 mL · 0.9% sodium chloride. Please show the division. I want to check my own against yours. I would like the general form as well…

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
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
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 mateo_iglesias 12k · 16 months ago
33 votes2 answers21k views
Is survodutide at 8 mg/mL stable enough for ten weeks of multi-withdrawal use?

The case in front of me: survodutide · 8 mg/mL · ten weeks. The claim is plausible, which is exactly why I want to check it. I am able to read a paper if someone…

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
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 ivo_paunovic 16k · 16 months ago
12 votes 5 answers14k views
How long does a Guangzhou to Japan lane usually take with tracking?

Details up front: Guangzhou · Japan. 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,…

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 greta_holzmann 23k · 16 months ago
12 votes 5 answers8.6k views
What should be in place before a first semaglutide vial arrives from Qingdao?

Concretely: semaglutide · Qingdao. The failure mode I am trying to avoid is making this decision emotionally. I have twelve months in view and I would like the plan…

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
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_Tomas_Kral 53k · 16 months ago
35 votes 5 answers46k views
What fraction of loss on semaglutide is lean mass according to SUSTAIN-6?

The case in front of me: semaglutide · SUSTAIN-6. I would like to know the limits of what can be inferred from this. What I am trying to avoid is over-reading a…

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…

127 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…

39 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…

39 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 per_haugen 13k · 16 months ago
25 votes 5 answers27k views
What is the reported incidence of hair thinning on semaglutide in STEP 3?

The case in front of me: hair thinning · semaglutide · STEP 3. I would like to know the limits of what can be inferred from this. What I am trying to avoid is…

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
clinical-trials
clinical-trials

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

745 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 per_haugen 13k · 16 months ago
6 votes 5 answers21k views
Would you re-test liraglutide after ten weeks at 30 °C, or accept the original certificate?

The particulars: liraglutide · ten weeks · 30 °C. I would like to define my thresholds before I have a result, for obvious reasons. I want a plan with explicit…

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
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 tobias_reint 20k · 16 months ago
13 votes 5 answers26k views
How many vial-days does a 4 mg vial give at 8 mg/mL on a weekly schedule?

For reference: 4 mg · 8 mg/mL. I would rather understand the derivation than memorise the outcome. Two people I asked gave two answers that differ by a factor of ten,…

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
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 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 pk_curve 30k · 16 months ago
26 votes 5 answers13k views
How many freeze-thaw cycles will tirzepatide at 4 mg/mL tolerate?

For reference: tirzepatide · 4 mg/mL. I want a method I can write down and repeat, not a rule of thumb. I would rather over-engineer this than discover a problem…

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…

57 questions
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
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 cake_collapsed 14k · 16 months ago
32 votes5 answers45k views
How comparable are oral semaglutide and liraglutide on the evidence available?

What I am working with: oral semaglutide · liraglutide. The comparison I want does not seem to exist anywhere in a form I can evaluate. I have read the arguments for…

clinical-trials
clinical-trials

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

745 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
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
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
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 tare_weight 60k · 16 months ago
12 votes 5 answers15k views
Is WXT worth the price difference against Nantong Guangyuan Chemical on measured results?

The particulars: WXT · Nantong Guangyuan Chemical. Both of these get recommended confidently by different people, which suggests neither is obviously right. My…

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
cost-analysis
cost-analysis

Cost arithmetic done honestly: cost per milligram after dead-space loss, list versus net price, comparing a multi-dose vial to a fixed-dose pen,…

260 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
asked by ten_mg_vial 31k · 17 months ago