Retatrutide vs Cagrilintide — different mechanisms, similar weight-loss research
Retatrutide and cagrilintide are both Novo Nordisk-or-Lilly research compounds investigated for chronic weight management, but they target completely different receptor systems. Retatrutide (Eli Lilly's LY-3437943) is a triple-agonist hitting GLP-1 + GIP + glucagon receptors. Cagrilintide (Novo Nordisk's NN-9838) is a long-acting amylin / calcitonin receptor analogue. Despite the mechanistic divergence, phase 2 trial data shows comparable mean weight-loss magnitudes (~24% retatrutide at 48 weeks; ~10% cagrilintide alone, ~15-20% with semaglutide combination). The more interesting research question is whether the safety / tolerability profiles diverge meaningfully and whether combinations across the two mechanisms (e.g. retatrutide + cagrilintide) would be supra-additive.
Side-by-side
| Retatrutide 40 mg pen | Cagrilintide 10 mg | |
|---|---|---|
| Receptor target | GLP-1 + GIP + glucagon | Amylin / calcitonin |
| Originator | Eli Lilly | Novo Nordisk |
| Half-life | ~6 days | ~7 days |
| Approval status | Phase 3 (TRIUMPH) | Phase 3 (REDEFINE) |
| Mono-therapy weight loss (48w) | ~24% mean | ~10% mean |
| Combination with semaglutide | Not formally tested | ~15-20% (CagriSema) |
| Mechanism class | Incretin polyagonist | Amylin analogue |
What to know
- ·Retatrutide produces larger mono-therapy weight loss than cagrilintide alone — but cagrilintide is investigated primarily in combination with semaglutide.
- ·The two mechanisms (incretin and amylin) are non-overlapping — combination protocols across both classes are an obvious research question.
- ·Side-effect profiles overlap heavily (GI effects), but cagrilintide trial reports suggest somewhat lower nausea than incretin-class compounds at matched weight-loss endpoints.
- ·Both are subjects of ongoing phase 3 programmes; primary readouts expected 2026-2027.
- ·Both are research-use only on this catalogue.
Where the literature diverges
Retatrutide research is concentrated in the TRIUMPH programme (Eli Lilly) and is positioned as the next-generation evolution of the GLP-1/GIP class beyond tirzepatide. Cagrilintide research is dominated by the CagriSema (with semaglutide) combination trials in the REDEFINE programme. Comparative head-to-head trials don't yet exist — the comparison is across separate trial cohorts with different baselines.
FAQ
Which one will get approved first?+
Both are in phase 3. Cagrilintide-as-monotherapy may not seek standalone approval if combination with semaglutide is the marketed product. Retatrutide is on track for late 2026 / 2027 approval. CagriSema combined approval timing is similar.
Could they be combined?+
Mechanistically yes — and the non-overlap suggests potential supra-additive effects. But no formal trial of retatrutide + cagrilintide exists. The tirzepatide + cagrilintide combination has been discussed in industry analyst reports but not formally trialled.
Which has the cleaner side-effect profile?+
Cagrilintide trial data shows somewhat lower GI symptom burden at matched weight-loss endpoints — the amylin pathway produces satiety with less direct gastric-emptying effect than incretin-class compounds. Both are dominated by transient nausea early in titration.
This is a research-context comparison of compound mechanism and published trial outcomes. Not medical advice. Both compounds are research-use only when sold by Omega Grade — for in vitro laboratory investigation, not human or veterinary administration.
- ResearchRetatrutide 40 mg pen
Retatrutide is a triple agonist at the GLP-1, GIP, and glucagon receptors. The 40 mg pen is the highest-dose presentation in the Omega Grade catalogue
- ResearchCagrilintide 10 mg
Cagrilintide is a long-acting amylin analogue most widely investigated in combination with semaglutide under the CagriSema programme. Commonly stacked
- ResearchRetatrutide 30 mg kit
Retatrutide 30 mg lyophilised vial kit — the mid-dose research presentation. Includes bacteriostatic water, syringes, and swabs.
- BiomarkerHOMA-IR 2.5
HOMA-IR is a calculated index from fasting glucose × fasting insulin. A HOMA-IR of 2.5 sits at the threshold most metabolic research uses for early insulin resistance, often years before HbA1c shifts.
- BiomarkerFasting insulin 12
Fasting insulin of 12 µIU/mL is above the optimal threshold most metabolic research uses (~8). What it indicates, why doctors miss it, and the research literature on early insulin resistance.
- BiomarkerHbA1c 5.7%
HbA1c at 5.7% is the formal threshold the ADA uses to define prediabetes — meaning your average blood glucose has been elevated over the past 2–3 months. What the number means and the research literature on intervention.