GLP-1 Research Overview: Semaglutide, Tirzepatide and Retatrutide

The incretin hormones GLP-1 and GIP help regulate insulin release and appetite signaling. Research compounds that mimic them have become some of the most studied peptides in metabolic research.

Semaglutide — GLP-1 receptor agonist

Semaglutide acts on the GLP-1 receptor alone. In the STEP 1 trial (Wilding et al., *New England Journal of Medicine*, 2021), adults with obesity receiving weekly semaglutide 2.4 mg saw a mean body-weight change of about −14.9% at 68 weeks, compared with −2.4% for placebo.

Tirzepatide — dual GIP and GLP-1 agonist

Tirzepatide activates both GIP and GLP-1 receptors. In SURMOUNT-1 (Jastreboff et al., *NEJM*, 2022), the highest dose (15 mg weekly) produced a mean weight reduction of about 20.9% at 72 weeks. Browse Tirzepatide.

Retatrutide — triple GIP, GLP-1 and glucagon agonist

Retatrutide adds glucagon-receptor activity. In a phase 2 trial (Jastreboff et al., *NEJM*, 2023), the 12 mg group reported a mean weight reduction of about 24.2% at 48 weeks. Phase 3 studies are ongoing. Browse Retatrutide.

Comparing them in research

• Mechanism: one, two or three hormone receptors.
• Evidence base: semaglutide and tirzepatide have completed large phase 3 programs; retatrutide data is earlier stage.
• Handling: all are supplied lyophilized and should be stored as described in our storage guide.

Researchers comparing several compounds often start with our Metabolic Starter Kit.

Trial figures are summarized from published studies for educational purposes. Products sold by Final Touch Wellness are for research use only.