Oral versus injectable exposure: comparing apples to a different fruit — a second dataset

Anyone comparing published oral and injectable efficacy should check whether the comparison is within one trial or across two. Across two, the populations differ and the comparison is weak.

Oral versus injectable exposure: comparing a 14 mg oral dose with a 0.5 mg injectable dose is comparing apples to a different fruit. The oral bioavailability is low enough that dose numbers are an order of magnitude different and not directly comparable.

Post #13 put the caveat in the right place and I want to underline it.

Orforglipron is a small molecule rather than a peptide, which changes almost everything about how it is made, stored and analysed. Comparing it to oral semaglutide as though they were the same pharmaceutical problem is a category error.

Take the reasoning and check the arithmetic; I do not always get it right.

Timing consistency matters more for oral dosing than for weekly injection, because absorption depends on the state of the stomach and the state of the stomach varies through the day.

That holds under the stated conditions and I have stated them.

Filing a mild objection to the consensus on Oral versus injectable exposure. Mild because I might be wrong; an objection because nobody has addressed the case that does not fit.

Why an oral formulation is a formulation achievement: the molecule is the same but the tablet is novel. Getting a peptide across the gastric epithelium at usable bioavailability is a chemistry problem, not a dose problem.

That is what I would do. It may not be what is correct.

The question underneath Oral versus injectable exposure is usually "how would I tell?" rather than "what is true?", and that one has a method attached to it.

Write down what you would expect to see under each hypothesis before you collect anything. If they predict the same observation, collecting it will not help.

This is the first time the answer has come with its own limits attached. Appreciated.

Building on post #21 rather than restating it.

PIONEER 6 was a cardiovascular safety trial for oral semaglutide, not an efficacy trial. Non-inferiority for safety was demonstrated. The point estimates favoured the drug but the trial was not designed to establish benefit.

I am reporting what happened, not recommending it.

Tablet integrity matters more than people expect for a formulation that depends on an absorption enhancer released at a particular place. Splitting or crushing is not a dose adjustment; it is a different product.

Research-use-only oral material is not a licensed tablet and there is no reason to assume it carries a functioning absorption-enhancement system at all. The formulation is most of the product here.

PIONEER programme is phase 3 for oral semaglutide. The trials cover multiple indications and durations. Reading them requires attention to which trial is which because they are not all the same question.

Written in the hope of being told what I have missed.

Post #26 is the version of this I will quote in future. One addition.

Dose numbers for oral formulations are not comparable to injectable ones. The 14 mg oral dose is not equivalent to any injectable dose in the traditional comparison sense. They are different formulations with different pharmacokinetics and cannot be put on the same scale.

Not the whole picture, but the part of it I can speak to.

Where I part company with post #24, and it is a narrow parting.

Reading back through the Oral versus injectable exposure threads from last year, the same three questions come up every time and only one of them has ever been answered properly. That seems like a documentation gap rather than a knowledge gap.

The gastrointestinal tolerability profile of the oral formulation is broadly similar in character to the injectable, which supports the effects being systemic rather than local irritation.

I am not the right person to answer the follow-up to this.

The absorption enhancer in the licensed oral product works by transiently raising local gastric pH and promoting absorption across the mucosa. It is the reason the fasting and water-volume instructions are specific rather than cautious.