Side by side

1. 1.Binds both GIP and GLP-1 receptors, with receptor signalling biased toward the GIP receptor.
2. 2.Increases insulin release and lowers glucagon in a glucose-dependent way.
3. 3.Slows gastric emptying and reduces appetite through hypothalamic signalling.
4. 4.GIP receptor activity appears to add to the effect on fat mass and possibly on how the body handles fat.
5. 5.Net effect: lower blood glucose and substantially reduced body weight.

• Type 2 diabetes (SURPASS programme)
• Chronic weight management in obesity (SURMOUNT programme)
• Obstructive sleep apnoea in people with obesity
• Heart failure with preserved ejection fraction and obesity
• Fatty liver disease

• HbA1c reduction of up to about 2.4 percentage points in trials
• Mean weight loss of roughly 20% at 72 weeks with the highest dose (SURMOUNT-1)
• Greater average weight loss than semaglutide 1 mg in a head-to-head diabetes trial (SURPASS-2)
• Improved blood pressure and lipid markers in trials
• Reduced apnoea-hypopnoea index in obesity with sleep apnoea

• Nausea, diarrhoea, vomiting and constipation, worst during dose escalation
• Reflux, belching and indigestion
• Reduced appetite and reduced food intake
• Injection-site reactions, fatigue and hair loss, all listed among the most common reactions in the FDA label
• Gallbladder disease
• Pancreatitis (rare; serious and sometimes fatal cases reported after marketing)
• Thyroid C-cell tumours in rodents — human relevance unknown

Research context only — tirzepatide is a prescription medicine and dosing is set by a doctor. Trial protocols escalated from 2.5 mg to 5–15 mg subcutaneously once weekly in 2.5 mg steps every four weeks, over 40–72 weeks. This is not a dosing suggestion.

Research context only