Vol. 3, No. 6 — June 2026Independent since 2024

TheCompound Journal

Reporting on incretins, compounding & the peptide supply chain

A monthly journal of record.
30 issues · 32 contributors
Not medical advice. We sell nothing.

Every letter we have printed

Page 61 of 77 of this archive, newest first.

Page 61 of 77 · back to the first page · 3,055 letters in total

On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 22 Jul 2024

I stopped eight months ago after reaching a weight I was happy with, and I have regained four of the twenty-two kilograms I lost. Every article I read told me to expect two-thirds back. I am not complaining, but I would like to know whether I am unusual or whether the two-thirds figure was always a mean concealing an enormous range.

E. Marchetti, Bologna

The Journal replies

The second. The published interquartile ranges around those means are wide, and outcomes like yours are well within them. The trials were not designed to explain why some people hold weight after cessation and others do not, and nothing measured at randomisation predicts it usefully. You are not an anomaly; you are part of a distribution nobody quotes.

On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 22 Jul 2024

Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.

L. Dziedzic, Wrocław

The Journal replies

Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.

On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 22 Jul 2024

I lost access for eleven weeks during the shortage, restarted at the dose I had been on because nobody told me otherwise, and spent a fortnight unable to keep food down. I had been on that dose for seven months without difficulty. Reading your resumption section was the first time anybody explained it.

E. Beauchamp, Ottawa, ON

The Journal replies

It is entirely predictable from the label and the pharmacokinetics, and the failure to communicate it during the shortage period was systemic rather than individual. We are sorry it reached you this way and we are glad it reached you.

On “Randomised withdrawal is the cleanest design in this field and the least…” — The Ledger, 22 Jul 2024

As a prescriber I would push back on your framing of the maintenance gap. We are not practising without evidence; we are practising on pharmacological inference, which is what clinicians do in every field where the trial has not been run. Calling it unevidenced makes reasonable practice sound reckless.

B. Wojciechowski, Kraków

The Journal replies

A fair objection and we have adjusted the wording. Our intention was to locate the absence with the people who could have funded the trial rather than with the clinicians managing without it, and on rereading the original paragraph did not achieve that.

On “A year after stopping: what the trials found at the far end” — Clinical Trials, 21 Jul 2024

You say no dose-equivalence data exists between agents in this class. During the shortage my pharmacy substituted one for another on the basis of a conversion table they had printed from somewhere. Where would such a table have come from?

A. Fournier, Nantes

The Journal replies

Almost certainly from cross-trial comparison of weight-loss percentages, which is not an equivalence basis. There is no head-to-head dose-titration study permitting conversion between these agents, and STEP 8 — the only head-to-head weight trial we know of — compared two agents at their own licensed doses rather than establishing equivalence between them.

On “Turnaround, cost and accreditation across the services this trade relies on” — Analytics, 21 Jul 2024

You keep saying you are criticising documentation and not honesty. I think that distinction is doing more work than it can bear. If a company knows buyers read a purity certificate as a safety document and issues one anyway, the omission is doing something.

H. Okwuosa, Enugu

The Journal replies

It is a fair challenge and we have thought about it. Our answer is that the convention long predates any individual company’s decision to follow it, that four of our correspondents told us plainly the products are not represented as sterile injectables, and that we have no evidence of anybody intending the inference readers draw. We will report intent when we can demonstrate it and not before.

On “Turnaround, cost and accreditation across the services this trade relies on” — Analytics, 21 Jul 2024

I photograph every cake now because of an earlier piece of yours, and last month it paid for itself. Two vials from the same box, one a proper matte plug and one a collapsed glassy disc. The supplier replaced both without argument when I sent the photographs.

E. Vandenberghe, Ghent

On “Turnaround, cost and accreditation across the services this trade relies on” — Analytics, 21 Jul 2024

Why did you submit only two vials for sterility testing when the whole article argues that the sample size is the problem? Two is worse than twenty by exactly the argument you make.

N. Bujanović, Sarajevo

The Journal replies

Because we could not afford twenty, and because the two results are reported as what they are: two vials, each destroyed, telling us nothing about their batches. The purpose was to establish that the test is commercially available to a private purchaser and what it costs, not to characterise anything. We should have said that in the article rather than in this reply.

On “Turnaround, cost and accreditation across the services this trade relies on” — Analytics, 21 Jul 2024

On multiple-dose closures: the puncture budget you refer to is generally in single figures for a standard lyophilisation stopper, and the qualification uses a new needle each time. Anybody reusing a needle through the same entry point is outside the data entirely.

S. Tovmasyan, Gyumri

On “Who signed this, and what did they undertake by signing it” — The Supply Chain, 20 Jul 2024

A technical query on your identity row: you specify 4111.1 Da monoisotopic with a tolerance of ±10 ppm, which is 0.04 daltons. Is that not tighter than most contract laboratories will commit to on a peptide of that size?

D. Ó Súilleabháin, Killarney

The Journal replies

It is achievable on an orbital trap with internal calibration and is tight for a quadrupole time-of-flight on external calibration. The row is drawn from a real certificate issued by a laboratory running the former. We should have said so, and the note now does.

On “Who signed this, and what did they undertake by signing it” — The Supply Chain, 20 Jul 2024

You put every documentary finding to the company before publication, which is admirable and also means you are letting companies that do not reply escape coverage entirely. Silence should have a cost.

K. Mwangi, Nakuru

The Journal replies

It does, and we should make it more visible. Non-response is recorded in the dossier register and published there. What we will not do is publish an inference we cannot support merely because nobody objected to it, and that constraint does protect the unresponsive. We accept the trade knowingly.

On “The arithmetic behind every identity confirmation, worked in full” — Explainers, 19 Jul 2024

The claim that a reproduced spectrum is worth more than any number in the document seems overstated. Most buyers cannot read a spectrum, and a printed image invites false confidence rather than scrutiny.

A. Nazarian, Glendale, CA

The Journal replies

Partly conceded. A spectrum is worth more to a reader who can read one, and this department exists partly to increase that number. But it is also an artefact that can be checked by a third party later, which a bare verdict is not, and that alone justifies printing it.

On “What the tirzepatide schedule assumes about a person it has never met” — Pharmacology, 19 Jul 2024

Your piece treats the four-week step as arithmetic, and I accept the arithmetic, but my prescriber moved me up every two weeks and I reached the top dose without difficulty. I do not think the schedule is as constraining as you suggest.

T. Brannon, Boise, ID

The Journal replies

Nor do we, and the file should have been clearer. The four-week interval is a floor below which the previous rung is still accumulating, not a threshold below which escalation is unsafe. Plenty of people tolerate faster ascent. Our objection is to the inverse inference — that because you did, everybody should — and to the absence of a trial that would let anyone say which is which in advance.

On “What the tirzepatide schedule assumes about a person it has never met” — Pharmacology, 19 Jul 2024

You keep insisting on peptide content rather than purity when discussing dose certainty. I have looked at a dozen certificates from four different testing services and content is reported on perhaps a third of them. What are readers supposed to do with an absence?

S. Lindgren, Uppsala

The Journal replies

Treat the nominal figure as an upper bound and say so out loud when reasoning about a dose. It is an unsatisfying answer and it is the honest one. We have argued in Analytics that content should be a standard reported field, and we will keep naming the services that report it and those that do not.

On “What the tirzepatide schedule assumes about a person it has never met” — Pharmacology, 19 Jul 2024

I want to object to the framing of dose reduction as measurement. In practice it is experienced as failure, and telling people it is a thermostat does not change how the appointment feels. The language problem is real and you have solved it rhetorically rather than actually.

T. Nkemelu, Port Harcourt

The Journal replies

A fair hit. We can describe the pharmacology accurately and still be writing at a distance from how the decision lands, and the paragraph you object to does both. The reframing is offered as a corrective to a stigma, not as a claim that the stigma is imaginary.

On “What the tirzepatide schedule assumes about a person it has never met” — Pharmacology, 19 Jul 2024

Thank you for saying plainly that the maximum dose is not the goal. I stopped at 10 mg fourteen months ago because it was working and I was tired of arguing about it. Every article I read before yours implied I had given up early.

L. Nyoni, Harare

On “What the tirzepatide schedule assumes about a person it has never met” — Pharmacology, 19 Jul 2024

As a prescribing pharmacist I would add one thing about re-titration. The commonest problem I see is not the resumption dose. It is that the patient has a pen left over at the old strength and uses it because it is in the fridge and it cost money. The clinical decision and the economic decision are not the same decision.

L. Marulanda, Medellín

The Journal replies

Well put, and we had not written it down. The cost of discarding partially used material is a real input into dosing behaviour in a market where much of the spend is out of pocket, and it deserves treatment in The Ledger rather than a sentence here.

On “Eating enough protein on a suppressed appetite is an arithmetic problem…” — Laboratory Notebook, 18 Jul 2024

Small correction to your table: the S-LiTE exercise prescription was two supervised group sessions and two individual sessions weekly, not two sessions in total. The distinction matters because "add some exercise" is not what was tested.

A. Lindholm, Gothenburg

The Journal replies

Correct, and that is precisely the point we were trying to make and then undermined in our own table. Amended.

On “What STEP 5 tells us about maintenance, and what it does not” — Patient Notes, 17 Jul 2024

Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.

G. Escalante, Lima

The Journal replies

Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.

On “What STEP 5 tells us about maintenance, and what it does not” — Patient Notes, 17 Jul 2024

I lost access for eleven weeks during the shortage, restarted at the dose I had been on because nobody told me otherwise, and spent a fortnight unable to keep food down. I had been on that dose for seven months without difficulty. Reading your resumption section was the first time anybody explained it.

D. Iversen, Aalborg

The Journal replies

It is entirely predictable from the label and the pharmacokinetics, and the failure to communicate it during the shortage period was systemic rather than individual. We are sorry it reached you this way and we are glad it reached you.

On “Why a result on one vial says less than the trade needs it to” — The Ledger, 17 Jul 2024

I run analytical services and I object to the framing of your blind comparison. You bought our cheapest tier, published the number it produced alongside a competitor’s most thorough package, and called the result a spread. It is not a spread. It is three different products, priced accordingly, and your own table says so two columns to the right of the headline figure.

B. Osei-Bonsu, Kumasi

The Journal replies

This is the objection we thought was most likely and we think it is partly right. The comparison is of standard products at standard prices, which is what buyers actually purchase, and we said so. But the presentation invites the reading you object to, and the figure caption now states the tier alongside each result rather than leaving it to the method columns.

On “Why a result on one vial says less than the trade needs it to” — The Ledger, 17 Jul 2024

I submitted a vial to one of these services last year, got a result three points below what the vendor advertised, and did not know what to do with it. Your article explains why: I had one measurement on one vial, no method comparison, and no way to know if my vial was representative. I still do not know what to do with it, but I understand the shape of not knowing.

L. Kowalski, Gdańsk

The Journal replies

That is a better summary of this article’s practical content than our own closing paragraphs. The one thing we would add is that your result is worth publishing wherever you can, because buyer-submitted results are the scarcest and most informative category in the entire corpus.

On “Lean mass is a compartment, not a tissue” — Clinical Trials, 16 Jul 2024

Your piece treats the one-quarter rule as discredited and then quotes fractions of one third and two fifths from the substudies as though those were more solid. They are group means from a hundred and forty people. Physician, heal thyself.

L. Kowalski, Gdańsk

The Journal replies

A fair hit, and we have amended the paragraph to carry the same caveat in both places. The distinction we should have drawn is that the substudy figures are at least attached to a stated population and a stated instrument, which the textbook rule is not. Neither is a constant.

On “Pore size, particle size, and why peptides need the wide pores” — Analytics, 16 Jul 2024

Acting on your section about system suitability, I asked a laboratory whether the criteria had been met on my run. They sent the suitability summary the same afternoon, unprompted and without charge, and it showed a tailing factor of 1.3 and replicate agreement well inside a per cent. Nothing was being withheld. Nobody had ever asked.

M. Sandhu, Amritsar

On “Pore size, particle size, and why peptides need the wide pores” — Analytics, 16 Jul 2024

A small technical correction. You write that trifluoroacetic acid is used at around 0.1 per cent. In peptide work concentrations of 0.05 to 0.1 per cent are both common, and some methods run higher for particularly basic sequences. The figure reads as though it were a standard rather than a range.

D. Chukwuma, Onitsha

On “Pore size, particle size, and why peptides need the wide pores” — Analytics, 16 Jul 2024

Your table of what each method can see puts "only if resolved" against isoaspartate for RP-HPLC. That understates the difficulty. Resolving isoAsp from Asp routinely requires a method developed for the purpose, and on a generic gradient the two are frequently indistinguishable even at forty minutes.

P. McAlinden, Belfast

The Journal replies

Accepted, and the entry now reads that it requires a method developed for the purpose. Our original wording implied that a sufficiently shallow generic gradient would generally do it, which overstates what shallowness alone achieves.

On “What we asked twenty suppliers about stability data” — The Supply Chain, 15 Jul 2024

Eleven days in customs, and you describe it as a structural feature rather than a scandal. Why the restraint? A shipper advertising a cold chain that demonstrably does not survive a routine examination is making a claim it cannot support.

H. Fitzmaurice, Preston

The Journal replies

The restraint is about where the fault lies. Customs authorities are performing a lawful function and owe nobody a thermal record. The claim of end-to-end control is the thing we criticise, and we do criticise it, in the article and again in the closing. What we will not do is convert an unavoidable feature of international freight into an allegation against the shipper who could not see it either.

On “What we asked twenty suppliers about stability data” — The Supply Chain, 15 Jul 2024

Your section on freezing reconstituted solution stops short of the obvious question, which I will therefore ask. If a phosphate buffer shifts pH substantially on freezing, does that not mean the freezer is actively worse than the refrigerator for a buffered formulation, rather than merely unproven?

B. Sundqvist, Turku

The Journal replies

For a phosphate-buffered formulation, plausibly yes, and the mechanism is well documented. We stopped short because the magnitude is formulation-specific and because most reconstituted research vials are in unbuffered water or bacteriostatic water, where the argument is about the interface rather than about pH. We should have made that distinction in the text instead of leaving a gap for you to find.

On “What we asked twenty suppliers about stability data” — The Supply Chain, 15 Jul 2024

I have shipped temperature-sensitive material commercially for eleven years and your coolant arithmetic is right but generous. You assume the pack starts fully frozen. In practice packs are pulled from a freezer that is opened forty times a day, and a pack that starts at minus four with a soft core has lost a fair share of its budget before the box is closed.

J. Prendergast, Wollongong, NSW

The Journal replies

A good point and one we had not considered properly. The latent heat calculation assumes a fully solid pack at its melting point, and a partially thawed pack is exactly as much worse as the missing solid fraction. We have added a sentence and would welcome any data you can share on pack condition at packing.

On “Twelve minutes or forty: what gradient slope buys” — Explainers, 14 Jul 2024

Sub-two-micron columns changed everything about what is practical for peptide separations, but I would push back on the statement that particle size gains are costless. The pressure limit of most commercial instruments is three hundred bar, and trying to force 1.7-micron particles at eight millilitres per minute on a 4.6-millimetre column will send you there quickly. Peak capacity is not free.

H. Ravensworth, York

The Journal replies

Correct on the pressure cost, and that belongs in the method section. The trade-off is real, which is why many laboratories use core-shell superficially porous particles as a compromise: they are substantially cheaper than sub-two-micron packings, deliver most of the efficiency gain at a lower pressure, and the efficiency-cost-pressure triangle is the actual business decision people make. We should have named it.

On “What actually helps, ranked by evidence” — Pharmacology, 14 Jul 2024

Nothing in your file addresses the social dimension, which for me was worse than the nausea. Six months of declining invitations to meals, and explaining to family why I was not eating. The tables do not have a row for that.

E. Thistlethwaite, Sheffield

On “What actually helps, ranked by evidence” — Pharmacology, 14 Jul 2024

A small point of precision. You use "gastroparesis" in the tag list and then spend a paragraph saying it is not a synonym for drug-induced emptying delay. That is a slightly awkward position to hold.

V. Petrosyan, Yerevan

The Journal replies

It is, and it is a compromise with how readers search. The tag exists because that is the word people use; the glossary exists because it is the wrong one. We would rather be findable and then precise than precise and unread.

On “What competing on one number does to a market” — Explainers, 13 Jul 2024

The table showing what each method can detect is valuable but incomplete. You show no row for C-terminal truncation or N-terminal truncation as distinct phenomena. These are not rare, and they often elute differently depending on which end is missing. A generic gradient might resolve them; an improperly designed orthogonal method might not. The capability matrix should separate these cases.

E. Marchetti, Bologna

On “The lowest effective dose is a real concept with almost no data behind it” — The Ledger, 12 Jul 2024

As a prescriber I would push back on your framing of the maintenance gap. We are not practising without evidence; we are practising on pharmacological inference, which is what clinicians do in every field where the trial has not been run. Calling it unevidenced makes reasonable practice sound reckless.

S. Nortje, Stellenbosch

The Journal replies

A fair objection and we have adjusted the wording. Our intention was to locate the absence with the people who could have funded the trial rather than with the clinicians managing without it, and on rereading the original paragraph did not achieve that.

On “The lowest effective dose is a real concept with almost no data behind it” — The Ledger, 12 Jul 2024

You say no dose-equivalence data exists between agents in this class. During the shortage my pharmacy substituted one for another on the basis of a conversion table they had printed from somewhere. Where would such a table have come from?

T. Kirchner, Hamburg

The Journal replies

Almost certainly from cross-trial comparison of weight-loss percentages, which is not an equivalence basis. There is no head-to-head dose-titration study permitting conversion between these agents, and STEP 8 — the only head-to-head weight trial we know of — compared two agents at their own licensed doses rather than establishing equivalence between them.

On “The lowest effective dose is a real concept with almost no data behind it” — The Ledger, 12 Jul 2024

Your piece describes tapering as pharmacologically pointless and then spends three paragraphs making a case for it. Pick one.

N. Ó Broin, Sligo

The Journal replies

Both, we think, and deliberately. There is no pharmacological rationale, because there is no withdrawal syndrome and a week-long half-life produces its own decline. There is a behavioural rationale, which is different in kind and untested. Our objection is to tapers advocated in pharmacological language, not to the practice.

On “EGFR, cystatin C, and the check on the check” — Laboratory Notebook, 11 Jul 2024

A small thing but it matters in practice: your table gives amylase and lipase rising as a finding of unclear significance. In my laboratory we no longer report amylase at all for suspected pancreatitis, because lipase is more sensitive and more specific and having both invites the wrong one to be acted on.

S. Bergqvist, Malmö

The Journal replies

A reasonable position and increasingly the standard one. We report amylase because the trial data reported it, not because we think it should be ordered.

On “EGFR, cystatin C, and the check on the check” — Laboratory Notebook, 11 Jul 2024

My ferritin fell from 118 to 34 across a year on treatment and I was told this was expected because inflammation had fallen. Six months later I was clearly iron deficient. I appreciate the section on this being ambiguous, but the ambiguity was resolved in one direction and nobody looked.

T. Oyelowo, Abeokuta

The Journal replies

That is the failure mode the ambiguity produces, and it is the reason a transferrin saturation alongside costs almost nothing and resolves the question. We are sorry it went that way.

On “EGFR, cystatin C, and the check on the check” — Laboratory Notebook, 11 Jul 2024

My HbA1c was 6.1 before starting and 6.0 after four months. My clinic recorded this as no improvement in glycaemic control. My continuous monitor says my average glucose fell by a fifth over the same period. Which is measuring what?

J. Vasilenko, Chisinau

The Journal replies

Both are measuring correctly and the discrepancy is worth pursuing with your clinic rather than with us. A 0.1-point change is well inside the reference change value for HbA1c, so the assay has not detected a change; whether that is because the change is genuinely small or because something is affecting your glycation is not answerable from the numbers alone.

On “The fourteen-day problem, and what it does to a commercial testing model” — Analytics, 11 Jul 2024

Why did you submit only two vials for sterility testing when the whole article argues that the sample size is the problem? Two is worse than twenty by exactly the argument you make.

B. Tejeda, Santo Domingo

The Journal replies

Because we could not afford twenty, and because the two results are reported as what they are: two vials, each destroyed, telling us nothing about their batches. The purpose was to establish that the test is commercially available to a private purchaser and what it costs, not to characterise anything. We should have said that in the article rather than in this reply.