Skip to content
Specimen Atlas of Research Peptides81 plates · MIT
Side-by-side · Research reference

CagrilintidevsMelanotan-II

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

APhase 3HUMAN-REVIEWED35/64 cited
BPhase 1HUMAN-REVIEWED9/43 cited
Cagrilintide
Long-Acting Amylin Analogue · Phase 3
7.5%Additional weight loss vs semaglutideAhmed 2026
Once weeklyDosing frequencyBailey 2026
Dual AMYR/CTRReceptor agonismBailey 2026
SQ · Once WeeklyBailey 2026
Melanotan-II
MC1R + MC4R agonist · Tanning + sexual response
0.25–1.0 mgPer doseDorr 1996
Phase 1Evidence levelDorr 1996
~1 hrHalf-life
SQ · Abdomen · Loading 5–7 days, then maintenance

01Mechanism of Action

Parameter
Cagrilintide
Melanotan-II
Primary target
Amylin receptor (AMYR) and calcitonin receptor (CTR) heterodimeric complexesBailey 2026
MC1R (skin) + MC3R + MC4R (CNS sexual / appetite)Dorr 1996
Pathway
AMYR/CTR agonism → Central satiety signaling → Reduced food intake, delayed gastric emptying, suppressed glucagonBailey 2026
MC1R agonism → melanocyte tyrosinase → eumelanin synthesis. MC4R → autonomic sexual arousal centresDorr 1996Simerly 2023
Downstream effect
Central satiety induction, prandial glucagon suppression, reduced caloric intake, weight loss, improved glycemic controlBailey 2026Yamauchi 2026
Skin darkening, photo-protection, increased sexual desire / spontaneous erectionDorr 1996
Feedback intact?
Yes — acts via physiological amylin pathways
Origin
Second-generation non-aggregating long-acting amylin analogue designed for once-weekly dosingBailey 2026
Cyclic 7-AA modified α-MSH analog; designed at University of ArizonaDorr 1996
Antibody development

02Dosage Protocols

Parameter
Cagrilintide
Melanotan-II
Standard dose (combination)
Cagrilintide 2.4 mg + Semaglutide 2.4 mg (CagriSema)Yamauchi 2026
Phase 3 REDEFINE 5 trial dosing.
Monotherapy dosing
Dose-dependent, under investigation
Monotherapy trials reported in meta-analysis.
Frequency
Once weekly (subcutaneous)Bailey 2026
Long-acting formulation.
Daily during loading; 1–2× per week maintenance
Evidence basis
Phase 3 RCT (REDEFINE 5), meta-analysis of 3 RCTs (n=3545)Yamauchi 2026Ahmed 2026
Phase 1 + anecdotalDorr 1996
Duration
26–52 weeks in trialsYamauchi 2026
8–12 weeks per cycle
Route
Subcutaneous injectionBailey 2026
Loading phase
0.25–0.5 mg/day SQ × 5–7 daysDorr 1996
Builds up to visible tan.
Maintenance
0.5–1.0 mg 1–2×/week
After visible tan develops; supports with UV exposure.
Lower / starter dose
0.1 mg / day
Conservative starter — assess tolerability for nausea.
Reconstitution
Bacteriostatic water; protect from light
Timing
Evening preferred (24h tan-development cycle)
Half-life
~1 hour plasma; effects on melanocytes persist days

03Metabolic / Fat Loss Evidence

Parameter
Cagrilintide
Melanotan-II
Weight loss vs semaglutide
7.47% greater percentage weight lossAhmed 2026
CagriSema combination vs semaglutide monotherapy (meta-analysis).
Absolute weight change
Significantly greater absolute weight reductionAhmed 2026
Mean difference favoring combination therapy.
Mechanism
Central satiety inductionBailey 2026
BMI reduction
Significant BMI reduction vs comparatorAhmed 2026
Glycemic benefit
Reduced fasting glucose and HbA1cAhmed 2026
Synergistic effect with semaglutide in combination.
Lipid effects
Improvements in total cholesterol, LDL-C, HDL-C, VLDL-C, triglyceridesAhmed 2026
Body composition
Predominant fat loss with weight reduction
Mitochondrial function
In vitro effects on skeletal muscle mitochondria under metabolic stress conditionsOld 2026
C2C12 myotube study; clinical relevance under investigation.
Combination rationale
Multi-pathway approach: amylin (satiety) + GLP-1 (incretin)Lempesis 2026
Key publications
REDEFINE 5 (Yamauchi 2026) · Ahmed meta-analysis 2026 · Bailey review 2026Yamauchi 2026Ahmed 2026Bailey 2026

04Side Effects & Safety

Parameter
Cagrilintide
Melanotan-II
Gastrointestinal
Nausea, diarrhea (common with incretin-based therapies)Pardali 2026
Dietary management and nutritional monitoring recommended.
Injection site reactions
Local reactions possible with subcutaneous administration
Safety profile
Generally consistent with incretin-based therapies
Phase 3 and meta-analysis safety data.
Tolerability
Tolerability considerations similar to GLP-1RAs
Muscle preservation
Lean mass considerations during weight loss
In vitro mitochondrial effects observed; clinical impact under investigation.
Nausea
Common, especially loading phase
Flushing
Common transient
Spontaneous erection
Common in men — MC4R cross-effectDorr 1996
Increased mole / freckle pigmentation
Existing moles darken; new lesions possible
Melanoma risk
Theoretical concern — increased melanocyte activity; CAUTION in melanoma history
Appetite suppression
MC4R-mediated; mild
Pregnancy / OB
Contraindicated
Absolute Contraindications
Cagrilintide
  • ·Hypersensitivity to cagrilintide or formulation components
Melanotan-II
  • ·History of melanoma or atypical mole syndrome
  • ·Pregnancy / breastfeeding
  • ·Active uncontrolled hypertension
Relative Contraindications
Cagrilintide
  • ·Severe gastrointestinal disease
  • ·History of pancreatitis (incretin-based therapy consideration)
Melanotan-II
  • ·Significant freckling / dysplastic nevus
  • ·Personal or family melanoma history

05Administration Protocol

Parameter
Cagrilintide
Melanotan-II
1. Dosing frequency
Once-weekly subcutaneous injection. Long-acting formulation designed for weekly administration schedule.Bailey 2026
Add 2 mL bacteriostatic water to 10 mg vial → 5 mg/mL = 500 mcg per 0.1 mL. Light-protected.
2. Combination form
Co-formulated with semaglutide as CagriSema for single weekly injection combining amylin and GLP-1 receptor agonism.Yamauchi 2026Bailey 2026
SQ — abdomen. Rotate sites.
3. Injection site
Subcutaneous — typically abdomen, thigh, or upper arm. Rotate injection sites weekly to minimize local reactions.
Evening preferred. UV exposure (sunlight or tanning bed) helps develop tan.
4. Storage
Refrigerate 2–8°C. Follow product-specific storage instructions for pre-filled pens or vials. Protect from light.
Lyophilised: refrigerate, light-protected. Reconstituted: refrigerate ≤30 days.
5. Dietary considerations
Nutritional monitoring recommended during treatment. Dietary management strategies important for tolerability and outcomes.Pardali 2026
29–31G insulin syringe.

06Stack Synergy

Cagrilintide
+ Semaglutide
Strong
View Semaglutide

Cagrilintide (amylin receptor agonist) and semaglutide (GLP-1 receptor agonist) act on distinct receptor systems to produce synergistic weight loss through complementary mechanisms — central satiety via amylin pathways plus incretin-mediated glucose control and appetite suppression via GLP-1. Co-formulated as CagriSema, this combination demonstrates 7.5% greater weight loss versus semaglutide monotherapy in Phase 3 trials with additional benefits on glycemic control and lipid parameters.

CagriSema
Cagrilintide 2.4 mg + Semaglutide 2.4 mg
Frequency
Once weekly subcutaneous
Duration
26–52 weeks (trial data)
Primary benefit
Enhanced weight loss, improved glycemic control, multi-pathway metabolic modulation
Melanotan-II
— no documented stacks