Semaglutide gets all the press because it's a lot cheaper and actually available (barely available, but available). Tirzepatide is much more difficult to get access to, though IMO it should be the one that people default to if they're going to take this class of drug.
Semaglutide will probably have the most side effects because it only has one action (GLP-1 agonist). Tirzepatide has slightly lower side effects because it adds a dual action (GLP-1 agonist + GIP analogue) so it can act at a lower magnitude on the GLP-1 receptors to avoid strong side effects, while still having higher efficacy due to its additional, separate, GIP action.
LY3437943 looks even more promising, with fewer side effects. LY3437943 retains both the actions of Tirzepatide but adds a third action, glucagon receptor agonist. So it should be able to have higher efficacy at a lower equivalent dose than the other two (less action on GLP-1 and GIP mechanisms, fewer side effects).
Semaglutide will probably have the most side effects because it only has one action (GLP-1 agonist). Tirzepatide has slightly lower side effects because it adds a dual action (GLP-1 agonist + GIP analogue) so it can act at a lower magnitude on the GLP-1 receptors to avoid strong side effects, while still having higher efficacy due to its additional, separate, GIP action.
LY3437943 looks even more promising, with fewer side effects. LY3437943 retains both the actions of Tirzepatide but adds a third action, glucagon receptor agonist. So it should be able to have higher efficacy at a lower equivalent dose than the other two (less action on GLP-1 and GIP mechanisms, fewer side effects).