Tirzepatide

Tirzepatide is a single-molecule dual agonist that simultaneously activates both glucose-dependent insulinotropic polypeptide (GIP) receptors and GLP-1 receptors. This dual mechanism produces synergistic effects beyond either pathway alone. The GIP receptor component uniquely contributes to adipose tissue metabolism and may enhance lipid-lowering effects. Unlike selective GLP-1 agonists, tirzepatide's GIP activity may also reduce nausea, improving tolerability at equivalent doses.

SURMOUNT-1 (2022): 15 mg dose achieved 20.9% mean body weight reduction over 72 weeks — landmark result for a pharmacological intervention.

SURPASS-2: Head-to-head superiority vs Semaglutide 1 mg on both HbA1c and body weight reduction.

Lipid profile: Significant improvements in triglycerides, LDL-C, and apolipoprotein B observed.

Muscle preservation: Research indicates favorable lean-mass-to-fat ratio vs diet restriction alone.

GIP component: Hypothesized to contribute thermogenic and anti-inflammatory effects beyond pure GLP-1 action.