January 2025

The mechanism behind the mechanism

The receptor populations that produce satiety and the ones that produce nausea overlap substantially. That is why the ceiling of…

Holding a dose is a decision, not a failure

Nausea and gastric delay attenuate over weeks at an unchanged dose. That single physiological fact is the entire justification…

When to stop escalating and when to stop entirely

An effect is dose-limiting when it prevents adequate intake, prevents normal activity, or produces a risk of its own. Discomfort…

What the trials counted as intolerance

We set out the questions that distinguish a symptom to manage from a dose to change.

The interventions with trial support, and the much longer list without

Almost nothing in the standard management repertoire has been tested in a randomised trial in this specific population. We say…

Holidays, surgery, sickness: interruption in practice

Supply interruption is the commonest cause of unplanned re-titration in this market, and it is almost never framed that way.

Dual, triple, co-formulated: a taxonomy the coverage keeps collapsing

The glucagon arm raises energy expenditure and also raises hepatic glucose output. Balancing those is the whole engineering…

Who signed this, and what did they undertake by signing it

Two signatures — one who performed the work, one who approved its release — are the ordinary regulated convention and are almost…

Why a result on one vial says less than the trade needs it to

A result on one vial generalises to a batch only if the vial was drawn in a way that makes it representative — and nobody…

Why a dead-clean sterile filter can pass pyrogen straight through

Bacterial endotoxin is a heat-stable lipopolysaccharide from the outer membrane of Gram-negative organisms. It survives…

LAL, kinetic chromogenic, recombinant factor C: three ways to the same figure

Three compendial method families are in routine use and a fourth, based on a recombinant enzyme rather than crab lysate, is now…

Why a result on one vial says less than the trade needs it to

What a laboratory can and cannot know about the provenance, storage history and representativeness of what lands on its bench.

Oxidation, and the peroxide that came in with the surfactant

We describe each pathway in enough chemical detail to explain why it is invisible to the method the trade uses, because that is…

The empty half of every certificate of analysis

Every certificate circulating in this market answers a question about molecules. Almost none answers a question about organisms,…

Seasonal use, holiday use, and the honest state of the evidence

The schedules in circulation, described accurately, with their evidentiary status attached.

What STEP 5 tells us about maintenance, and what it does not

The commonest real-world strategy in this drug class is the least studied one.

Why the bone question is harder than the muscle question

A plausible mechanism, a measurable change, and no outcome data. This is what an open question looks like.

Thiamine and the vomiting patient

What the trials measured, which in the case of micronutrients is very little.

HbA1c and its lag: what a result three months old is telling you

A robust, cheap, standardised assay with a specific and well-catalogued set of failure modes, several of which are common in…

The dose that got you here and the dose that keeps you here

Every withdrawal trial compared full dose against nothing. The clinically interesting comparison — full dose against a reduced…

The one randomised trial that combined an incretin with supervised exercise

One randomised trial has combined a GLP-1 receptor agonist with supervised exercise. Its result is the single most useful piece…

Nought point nine eight of a dalton: the modification that hides in plain sight

What would be needed to catch each of these, and what it would cost.

Reproducibility, measured rather than assumed

The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and…

Counter-ion, water, salt: three masses with no chromatogram

An orthogonal method separates on a different physical principle, so that species co-eluting in the first are likely to resolve…

What twenty companies say about storage, and what they have measured

Storage instructions in this market are close to uniform and almost never accompanied by the study that would justify them.…

Everything on the page, in the order a chemist would read it

The purity figure is the least informative line on a well-constructed certificate and the only line most buyers read.

The retest date and the expiry date are not the same document

We asked twenty companies three questions about stability data and print every answer, refusal and non-response.

The question no chromatogram has ever answered

Every certificate circulating in this market answers a question about molecules. Almost none answers a question about organisms,…

When to stop escalating and when to stop entirely

An effect is dose-limiting when it prevents adequate intake, prevents normal activity, or produces a risk of its own. Discomfort…

The lowest effective dose is a real concept with almost no data behind it

Dose reduction is not withdrawal, and the trials that tested withdrawal cannot be read as testing it.

The intramuscular injection nobody intended

Skin thickness at the standard injection sites is approximately two millimetres in adults and varies remarkably little with body…

The arithmetic of a step: what doubling a dose actually asks of you

What the published pharmacokinetics permit, what the labels state, and where the two diverge.

Why your laboratory interval differs from the one in the textbook

A flag is a probability statement about a population. It is not a statement about the person holding the printout.

Percentage of loss, absolute kilograms, and the sleight of hand between them

The trials measured mass. Nobody measured whether the participants got weaker.

Priming a pen is not optional

For licensed products the in-use period is established by stability data. For a peptide reconstituted at home there is no such…

Why "muscle-sparing" is a marketing term and not a measurement

Grading six widely repeated claims against the studies actually behind them.

What SURPASS-4 tells us about maintenance, and what it does not

Every withdrawal trial compared full dose against nothing. The clinically interesting comparison — full dose against a reduced…

How a claim degrades between the bench and the listing

The Journal does not treat a badge as evidence and states so wherever it reports one.

Six words a verification badge would need to mean anything

What a verification mark would have to carry to be checkable: a date, a lot, a method, a submitter and a link to the report.

Side effects, cost, supply, target: four reasons with four trajectories

A supply interruption is a discontinuation with no notice, no taper and no plan. That is a distinct clinical situation.

Sending the same vial twice, under two names

The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and…

The supply gap as a clinical event

Why the reason for stopping changes what happens afterwards.

Three services, one lot, and a spread of two and a half points

Two years ago we ran an anonymised version of this comparison and promised a named one. This is it, with every method printed in…

Randomised withdrawal is the cleanest design in this field and the least discussed

The evidence on stopping is better than the evidence on almost anything else in this field, because somebody deliberately…

Bacteriostatic water, sterile water, and the 0.9 per cent that makes the difference

Every degradation pathway accelerates by orders of magnitude on reconstitution, because the solvent that lyophilisation removed…

What the outcome trials measured in the kidney

Asymptomatic pancreatic enzyme elevation is common on treatment and is not pancreatitis. The distinction is clinical, not…

Resolution, tailing, repeatability: the arithmetic before the result

System suitability is the set of checks demonstrating that the instrument and method were performing adequately when your sample…

Why the compendial sterility test is a rejection test and nothing more

The compendial sterility test cannot demonstrate that a batch is sterile. It can only fail a batch that is grossly contaminated.…

The last mile is the warmest mile

The honest finding is more nuanced than the alarm: a lyophilised cake tolerates a brief warm excursion far better than a…

At 214 nanometres you see every peptide bond. At 280 you see three residues.

Area per cent silently assumes that every species in the sample absorbs as strongly per unit mass as the parent. For peptide…

The change that weighs nothing at all

Deamidation adds 0.98 daltons. On a low-resolution instrument at incretin molecular weights, that is inside the noise.

The arithmetic behind every identity confirmation, worked in full

A peptide has a monoisotopic mass and an average mass, they differ by several daltons at this molecular size, and a certificate…

What the GLP-1 receptor actually does when exenatide binds it

The receptor is expressed in more tissues than the popular account allows, and that is the whole story.

A number without a suitability record is a number from an unknown instrument

System suitability is the set of checks demonstrating that the instrument and method were performing adequately when your sample…

The word “confirmed” is doing an enormous amount of work on this certificate

An intact mass measurement establishes elemental composition, at best. The number of distinct sequences consistent with a given…

The certificate says 2025. The vial in your hand does not say anything.

What happens to traceability when bulk material is subdivided, repackaged and relabelled two or three times before sale.

The site you keep using is the site that stops working

Lipohypertrophic tissue is less painful to inject into, which is precisely why people keep injecting into it.

Everything a buyer assumes has been checked, ranked by whether it has

The absences are not concealment. They are the form the trade settled on, and no buyer has ever objected.

When to stop escalating and when to stop entirely

We set out the questions that distinguish a symptom to manage from a dose to change.

Hydration, protein and the two failures that compound each other

Dietary measures are widely recommended, plausible on mechanism, and supported mainly by observational data and clinical…