This gets cited here weekly, usually second-hand, so it is worth setting out what it does and does not establish.
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.
Where I think it is weakest: the comparator does most of the work in how this gets reported, and it is not the comparator most people think they are citing.
The bit I cannot resolve on my own 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. I have searched first, so if this is covered somewhere point me at it and I will read it.
Figures above are from the primary publication rather than the press summary. If a number here disagrees with one you have, post yours and we will work out which of us is reading a secondary source.
MASHdoc_SA 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.
MASHdoc_SA 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].
[1] Day JW, et al. Nat Rev Drug Discov. 2022;21:37-54.
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Shop Reference StandardsTaking the question as asked, rather than the general version of it. 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.
BethLabQueen said:Agreed, and ALT falling is not the same as fibrosis improving.
This matches mine closely enough to be worth saying so out loud. I had assumed I was the exception until I read this.