Collecting this in one place because it comes up every few weeks and the answer is always assembled from scratch. It is about the glucagon co-agonists, and it is deliberately narrow — everything I am not confident about is marked as such.
The glucagon co-agonists — survodutide, mazdutide, ecnoglutide — are all chasing the same idea: add energy expenditure to appetite suppression. The liver signal is where they look strongest, because hepatic fatty-acid oxidation responds to glucagon directly rather than as a consequence of weight loss.
Worth remembering these are at different regulatory stages in different regions, and a phase 2 result in one jurisdiction is being quoted here as if it were a global standard of care.
What I am after is whether the liver signal is independent of weight loss or downstream of it, because that determines whether any of this is interesting for someone whose weight is already where they want it. Tell me what I have not thought of.
FranDenver said:The glucagon co-agonists — survodutide, mazdutide, ecnoglutide — are all chasing the same idea: add energy expenditure to appetite suppression.
Agreed, and ALT falling is not the same as fibrosis improving. Enzymes are a crude proxy; FIB-4 or elastography is what tells you about the thing that matters.
FranDenver said:The glucagon co-agonists — survodutide, mazdutide, ecnoglutide — are all chasing the same idea: add energy expenditure to appetite suppression.
Glucagon receptor pharmacology in triple agonists (retatrutide), relevant to the glucagon co-agonists: the glucagon component is the most controversial because glucagon traditionally raises blood glucose. So why include it in an anti-obesity drug?
Key insight: glucagon increases energy expenditure (thermogenesis), promotes hepatic lipid oxidation, and reduces appetite through distinct CNS mechanisms. The hyperglycemic effect is counterbalanced by the GLP-1 component's insulin secretagogue action.
Net result: more weight loss through increased expenditure (glucagon) + decreased intake (GLP-1/GIP), with neutral or improved glycemia. An elegant pharmacological balancing act[1].
Community-driven peptide testing and vendor rating platform. Transparent results. Unbiased analysis. Trusted by thousands.
View ResultsThis one has a reasonably settled answer, so here it is. The liver data is among the strongest non-weight findings in the class. The semaglutide MASH programme reported a large advantage over placebo on MASH resolution, with a substantial minority also achieving fibrosis improvement — and fibrosis is the endpoint that predicts outcomes. Mechanistically it is reduced hepatic lipogenesis, increased fatty-acid oxidation, less hepatic inflammation, and possibly a direct effect on stellate-cell activation.
Dr.PainCLE said:Agreed, and ALT falling is not the same as fibrosis improving.
Same pattern here, and in the same order. The detail I would add is minor and it is already implied above.