About to suggest that same research is relevant here. A small percentage of people just don't respond well to any given option in this drug class, and this could realistically fall into that category, assuming the compound itself is genuinely fine. Responses to other options in the class also tend to be weak in those cases, though clearly there was a decent response to the earlier medication here. The only explanation that's made sense involves how the different mechanisms interact. That theory points toward the idea that if the response mostly traced back to one particular pathway rather than the extra ones this newer compound targets, sticking with the earlier medication might actually work better, even though that's a bit painful to admit given the newer options tend to outperform for most people.
As for zero movement given the current weight, activity level, and reported intake, that's genuinely hard to reconcile. If a much larger amount had already been lost with major metabolic adaptation from sustained low intake, that would make more sense. Or a long history of restricted eating beforehand. The most obvious explanation ties back to the mountain of research showing people are just genuinely bad at estimating what they actually eat, not meant as a criticism, just the reality.
