Retatrutide vs Cagrilintide

Two different mechanisms

Retatrutide is a triple agonist acting at the GLP-1, GIP and glucagon receptors, so it combines appetite suppression with an increase in energy expenditure driven by the glucagon arm. Cagrilintide is a long-acting amylin analogue: it slows gastric emptying and promotes satiety through a pathway that is entirely separate from the incretin system.

Weight-loss data side by side

Retatrutide's Phase 2 programme reported roughly 24% mean body-weight reduction at 48 weeks on the highest dose — the largest figure published for any single agent to date. Cagrilintide as a monotherapy produced around 10-11% at 26 weeks, and its main development path is as a combination with semaglutide (CagriSema), where the pairing has reported figures in the low 20% range.

Dosing and titration

Both are once-weekly subcutaneous injections. Retatrutide titrates upward in steps over several months to limit gastrointestinal side effects, typically starting near 2 mg. Cagrilintide titrates from roughly 0.3 mg toward 2.4 mg weekly. Because their mechanisms do not overlap, the two are dose-titrated independently rather than mirroring each other's schedules.

Side-effect profiles

Nausea, reduced appetite and constipation are common to both. Retatrutide's glucagon component can raise resting heart rate and, at higher doses, transiently affect glucose handling, so it warrants closer monitoring. Cagrilintide's adverse-event profile is dominated by gastrointestinal complaints and tends to be milder in isolation.

Which fits which goal

For maximum weight reduction from a single compound, the retatrutide data is currently unmatched. For a gentler curve, or as an add-on to an existing GLP-1 protocol where an incretin ceiling has been reached, an amylin analogue such as cagrilintide adds a non-overlapping satiety mechanism. Availability differs too — neither is fully approved, but cagrilintide's combination path is further along in regulatory review.

Frequently asked questions

Is retatrutide stronger than cagrilintide?

On published weight-loss data, yes — retatrutide reported roughly 24% at 48 weeks versus about 10-11% for cagrilintide monotherapy at 26 weeks.

Can retatrutide and cagrilintide be stacked?

There is no clinical data on that combination. Amylin analogues are being trialled with GLP-1 agonists, not with triple agonists, so stacking them is unstudied.

How often is cagrilintide injected?

Once weekly subcutaneously, the same cadence as retatrutide.

Which has fewer side effects?

Cagrilintide alone is generally the milder of the two, since it lacks the glucagon-receptor activity that drives retatrutide's heart-rate and glucose effects.