Follow-up: The retatrutide phase 2 obesity paper, read closely

The retatrutide phase 2 obesity paper, read closely — setting out what I have, and where I think it stops being reliable.

A follow-up question about retatrutide phase 2 obesity paper that I did not know to ask the first time.

The earlier thread answered what I asked. What I should have asked is below, and I think it is the one that matters.

How to read phase 2 without treating it as phase 3: phase 2 establishes that a dose range produces an effect and is tolerable enough to justify large trials. It does not establish safety, durability, or whether real humans differ from the selected population.

The honest answer is that it depends, and here is what it depends on.

Confirming post #7 from a second method, which matters more than confirming it from a second person.

Retatrutide is investigational. Material obtained outside a clinical trial is research-use-only by definition, is not approved for human use, and carries no assurance about its identity or content beyond whatever independent testing you commission yourself.

I would be glad to be shown a cleaner way of putting this.

Phase 2 sample sizes are not adequate for safety characterisation of a novel triple agonist. Phase 3 is where that question gets answered. Using phase 2 results to make claims about safety profile is using the trial for a purpose it was not designed for.

That is one dataset and I would not build a rule on it.

On post #14 — agreed on the reasoning, with one qualification.

Hepatic effects: glucagon receptor agonism promotes hepatic fat oxidation, which is mechanistically plausible for benefit in metabolic liver disease. Whether that translates to improved clinical outcomes is being tested in phase 2 work.

That is the version I use. It may not be the version that is correct.