u/janek_ferrari

Agreed — units are volume. Once that lands, the rest of the arithmetic is one division.

Show the arithmetic — where did the unit figure come from?

stretching to ten days then twelve is the pattern people report

Agreed — and the exposure lag means the first fortnight tells you almost nothing.

research-use-only material is not approved for human use, full stop

How many mg in the vial and how many mL are you adding?

aim the stream at the glass wall, not at the cake

Read the phase 2 paper twice before ordering anything. Recommend that to anyone in this board: the error bars are the interesting part.

That is sterile water, not bacteriostatic. Same appearance, different product, and it matters for a multi-draw vial.

identity and quantity are two questions and most documents answer one

This is the sentence to take away. The rest of the thread is footnotes to it.

wait for phase 3 before you argue about rankings

Is water content on the document? It changes your concentration arithmetic.

LC-MS gives you identity; UV purity gives you a relative quantity.

Adding the bit that always gets missed: the lot on the vial has to match the lot on the page, or none of this applies to your material.

axis labels included, always

Is that a U-100 syringe? The barrel markings change the answer completely.

LC-MS gives you identity; UV purity gives you a relative quantity. A document with the first and not the second, or the reverse, is answering half the question.

Correcting my own comment: the two draws were 3 weeks apart, not the figure I gave earlier.

Took a baseline the week before starting purely because this board told me to. Best five minutes I have spent on this.

Tracked A1c against the weight trend for a year. The correlation was much weaker than I expected and that was worth knowing.

bring the numbers to someone qualified to read them

Cosigning. The batch identifier is load-bearing, and a certificate that cannot be tied to the vial in your hand is not about your vial.

The dead space question sent me down a rabbit hole for a week. It is a fraction of a unit and it is the same every draw.

Yes. Writing 3.33mg/mL on the vial takes four seconds and removes the entire class of error this board exists to fix.

assay method matters, especially between different labs

Adding the obvious one — take it to whoever ordered the panel. This board cannot read it for you.

Same lab as the previous draw?

bring the numbers to someone qualified to read them

Repeat testing before acting is standard practice for a reason: regression to the mean does a lot of work on single outlying values.

That is a pause rather than a stop, and the plans for the two are not the same.

Is that the same assay, or did the lab change platforms?

Same lab as the previous draw?

How many weeks between the two measurements?

That is the catalogue certificate rather than the batch-specific one. Same layout, completely different status.

dose escalation in the trials was slow for a reason

Research-use-only material is not approved for human use, so treat everything in this thread as arithmetic about solutions rather than instructions for a person.

Fasting or not, and what time of day?

The phase 2 readout ran to 48 weeks in a few hundred participants with a slow escalation.

Agreed, and the glucagon arm is exactly why the comparison threads do not work.

LC-MS gives you identity; UV purity gives you a relative quantity. A document with the first and not the second, or the reverse, is answering half the question.

ask for the storage condition the stability statement was written against

not approved anywhere, which is the single most important fact in this board

That comparison crosses two labs with different assays. The difference you are describing may be the method.

Draw at the same point in the week now, fasting, same lab. The noise dropped enormously once I standardised.