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5.2k questions · page 148 of 217

35 votes 4 answers27k views
How many freeze-thaw cycles will orforglipron at 2 mg/mL tolerate?

What I am working with: orforglipron · 2 mg/mL. This is a procedural question rather than a theoretical one, and I would like the procedure rather than the theory.…

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
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 anders_vestby 8.5k · 19 months ago
37 votes5 answers47k views
Does early satiety at week two of survodutide usually resolve without a dose change?

The case in front of me: early satiety · two · survodutide. This is a procedural question rather than a theoretical one, and I would like the procedure rather than…

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
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 · 19 months ago
35 votes 5 answers34k views
What does TRIUMPH-1 tell me about dizziness at the 8 mg dose?

Setup, so nobody has to ask: TRIUMPH-1 · dizziness · 8 mg. I would like help reading this properly rather than being told what conclusion to reach. I have the full…

clinical-trials
clinical-trials

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

745 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 threadlock7 19k · 19 months ago
15 votes5 answers15k views
What fraction of loss on tirzepatide is lean mass according to SURMOUNT-5?

Setup, so nobody has to ask: tirzepatide · SURMOUNT-5. I would like help reading this properly rather than being told what conclusion to reach. I have the full report…

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
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 gel_pack_warm 13k · 19 months ago
22 votes 5 answers35k views
Can I reconstitute retatrutide at 2 mg/mL and still measure a small dose accurately?

Stated plainly: retatrutide · 2 mg/mL. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my tolerance…

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
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 retest_please 9.7k · 19 months ago
22 votes 5 answers29k views
Is 6.67 mg/mL a sensible working concentration for cagrilintide, or should I go lower?

Stated plainly: 6.67 mg/mL · cagrilintide. Both of these get recommended confidently by different people, which suggests neither is obviously right. My constraints…

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
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 nominal_ten 12k · 19 months ago
37 votes 5 answers41k views
My dulaglutide vial sat at 25 °C for ten days — is testing worth it before use?

Stated plainly: dulaglutide · 25 °C · ten days. I would like to set this up properly once, rather than adjust it repeatedly. My budget is real but not tight, and my…

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
peptide-stability
peptide-stability

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

908 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
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 tess_amankwah 22k · 19 months ago
4 votes 5 answers19k views
Does hydrolysis of dulaglutide at minus 20 °C show up as a loss of content or of purity?

Details up front: hydrolysis · dulaglutide · minus 20 °C. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring…

peptide-stability
peptide-stability

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

908 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
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
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 priya_menon 13k · 19 months ago
9 votes5 answers13k views
Does holding at 0.5 mg for six weeks before escalating reduce vomiting?

Details up front: 0.5 mg · six weeks · vomiting. I suspect the usual explanation for this is wrong, or at least incomplete. I am aware this may have a boring 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
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
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 bea_forsberg 11k · 19 months ago
26 votes 5 answers13k views
Why has a parcel to the United States sat at a customs facility for five days?

The particulars: the United States · five days. Before I write this off, I want to check whether it is a known failure mode. I have the lot number, the certificate…

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
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
import-regulations
import-regulations

The legal framework for personal importation across major jurisdictions, enforcement discretion, and the distinction between a research reference…

53 questions
asked by Dr_Aoife_Brennan 20k · 19 months ago
39 votes 5 answers33k views
Would a sterility test distinguish dimerisation from a synthesis impurity in tirzepatide?

The case in front of me: a sterility test · dimerisation · tirzepatide. I have used one of these for a while and I am considering switching, which requires a reason.…

peptide-mapping
peptide-mapping

Enzymatic digestion followed by LC-MS/MS to confirm sequence rather than just mass. The method that catches a scrambled sequence or a D-amino-acid…

103 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
mass-spec
mass-spec

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

52 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
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 assay_blank 45k · 19 months ago
2 votes 5 answers5.2k views
How much protein in grams do I need at 103 kg on 900 kcal a day?

Conditions: 103 kg · 900 kcal. 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 as the…

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 tri_gly_ala 24k · 19 months ago
20 votes 5 answers15k views
How long does survodutide stay within specification at 40 °C once reconstituted?

The case in front of me: survodutide · 40 °C. I am trying to do this correctly the first time rather than learn it by getting it wrong. I have already made one…

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
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 juan_esquivel 14k · 19 months ago
8 votes 5 answers21k views
What is the real-world lead time from Guangzhou to Norway in winter?

Stated plainly: Guangzhou · Norway. The figures are clear enough; the question is what they mean and what they do not. I can supply the numbers if the specifics…

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 mala_venkatesh 22k · 19 months ago
18 votes 5 answers29k views
Is a mini-fridge good enough for storing reconstituted oral semaglutide?

Conditions: a mini-fridge · oral semaglutide. I want to decide this in advance so that I am not deciding it under pressure later. Assume I will follow the plan I…

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 colm_dunphy 8.2k · 19 months ago
12 votes 5 answers19k views
How comparable are liraglutide and mazdutide on the evidence available?

What I am working with: liraglutide · mazdutide. I am trying to choose between two options that are usually discussed as though only one exists. I am not optimising…

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
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
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 sample_id 17k · 20 months ago
32 votes0 answers16k views
Does a phase-change pack hold a tirzepatide shipment for ten days in transit?

What I am working with: tirzepatide · ten days. I would like the arithmetic checked rather than the conclusion asserted. I have deliberately not used an online…

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
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 Dr_Fatima_Belkacem 18k · 20 months ago
6 votes 5 answers8.5k views
Is 1.6 g/kg protein evidence-based during an energy deficit?

I have three DEXA scans on the same scanner at twelve-week intervals, fasted, same time of day. I would like to know whether this claim survives contact with…

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
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 greta_holzmann 23k · 20 months ago
9 votes5 answers15k views
Has anyone independently verified a GGPeps survodutide batch COA?

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

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
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
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 coldbox9 41k · 20 months ago
21 votes 5 answers39k views
What does PIONEER-4 actually establish about oral semaglutide?

The particulars: PIONEER-4 · oral semaglutide. 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
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
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
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 tenth_of_a_unit 57k · 20 months ago
19 votes 5 answers20k views
How do I compare GL Biochem and QST on lead time to Sweden?

The specifics, since they change the answer: GL Biochem · QST · Sweden. I am trying to choose between two options that are usually discussed as though only one…

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
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
asked by s_bhattacharya 31k · 20 months ago
17 votes5 answers20k views
What did the placebo arm of FLOW report for hair thinning?

Stated plainly: FLOW · 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 comfortable…

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 birk_nordahl 16k · 20 months ago
12 votes 5 answers23k views
What is a sensible monitoring routine for liraglutide over three weeks?

Details up front: liraglutide · three weeks. 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
plateau
plateau

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

36 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 charge_state_3 16k · 20 months ago
27 votes5 answers28k views
Is there any published stability data for orforglipron at room temperature?

Concretely: orforglipron · room temperature. This has the shape of a fact but I cannot find its origin. What I found instead were three secondary sources all citing…

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
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 mala_venkatesh 22k · 20 months ago