This gets cited here weekly, usually second-hand, so it is worth setting out what it does and does not establish.
STEP 4 is the study that answers this and it is blunt. Participants who continued kept losing; participants switched to placebo regained about two thirds of what they had lost within a year, and the metabolic improvements faded with the weight. That is the same pattern as every other chronic-disease medication ever withdrawn, and it is an argument about the condition rather than about the drug.
Where I think it is weakest: the population was selected and supported in ways a real cohort is not, so I would read the effect size as a ceiling rather than an expectation.
What I am after is whether there is a lowest maintenance dose with actual maintenance data behind it, or whether everything published sits at the top of the ladder. Not looking for reassurance. Looking for the part I have got wrong.
Note on sourcing:
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.