This site has covered rescue therapy after surgery in what eight studies found, all of it observational. This is the randomized version, in exactly the group the question is asked about: people whose operation did not deliver what was hoped [1].
The comparison is unusually stark, and the placebo arm is why. Over 68 weeks, participants on semaglutide lost 18.0% of their body weight while those on placebo gained 0.4% — an adjusted difference of 19.18 percentage points (95% CI -23.4 to -14.8). Metabolic parameters and quality of life improved alongside — measured with the kind of instrument examined in the health utility analysis.
One feature of the design strengthens the result rather than weakening it. Everyone enrolled had already responded poorly to surgery, which is a selected group, and selected groups usually drift back toward the average — meaning the placebo arm had room to improve without any treatment. It did not; it gained slightly. That is the opposite of the regression-to-the-mean pattern described in the depression score analysis, and it makes the contrast more trustworthy.
The safety line deserves reporting in full because it is the kind that gets dropped. There were eight serious adverse events and one suspected unexpected serious adverse reaction, with no treatment-related deaths, and the authors describe the overall profile as consistent with what is known about semaglutide. A suspected unexpected serious adverse reaction is a specific regulatory category meaning something happened that the drug’s label did not anticipate.
For someone in this position the practical content is real. Roughly one in four people who have bariatric surgery does not reach the expected result, and until now the evidence for adding a drug afterwards was cohorts and case series. The cost of running both paths is set out on this site’s sister publication, and the timing question — whether to add the drug before anything goes wrong — is examined in surgery against a GLP-1 on cardiovascular outcomes.