Retatrutide vs semaglutide — comparing across trials is the trap here
There is no direct head-to-head between these. Every comparison you see is cross-trial.
Cross-trial comparison is unreliable for reasons that are boring but decisive: different populations, different entry criteria, different durations, different background care, different analysis conventions (completer analysis versus intention-to-treat changes reported numbers substantially).
So when someone puts retatrutide's phase 2 figure next to semaglutide's phase 3 figure and subtracts, that number is not meaningful.
Evidence tier: semaglutide approved with completed phase 3 programmes. Retatrutide investigational, phase 2.
The honest answer to "which is better" is that the comparison hasn't been made, and mechanistically they're not doing the same thing anyway — one receptor versus three.