Given GIP agonism seems to be better (Tirzepitide/VK2735/Roche CT-388) than GIP inhibition per the messages you referenced. Amgen is going forward on the basis of MariTide is a longshot in Obesity IMO and the only company going after this MOA. I did note that Amgen is also going after T2D with Maritide.
So the Oral (AMG736) is out and they didn't ever say why or what the MOA was. I will remove the Amgen entry next time I update the list of ORAL obesity drugs.
Overall, the idea that the Market cap of Amgen went up $15B or 12% on the Maritide news that "management is encouraged/pressing ahead" is very surprising but we have seen this before. NVO's stock reaction to the Amycretin "news" given the release of very little data was also surprising.