Side-by-side · Research reference

MT-1vsTesamorelin

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

AFDA-ApprovedHUMAN-REVIEWED9/51 cited

BFDA-ApprovedFlagship27/68 cited

MT-1

α-MSH Analogue · FDA-Approved

16 mgImplant dose

13 AAPeptide lengthChawathe 2026

2019FDA approval

SQ Implant · 60-Day Release

Tesamorelin

GHRH Analogue · FDA-Approved

2 mgDaily doseEGRIFTA® (tesamorelin for inje 2010

15–20%VAT reductionFalutz 2010

~26 minHalf-lifeEGRIFTA® (tesamorelin for inje 2010

SQ · Abdomen · Once Daily

01Mechanism of Action

Parameter

MT-1

Tesamorelin

Primary target

Melanocortin-1 receptor (MC1R) on melanocytesLangan 2010

Hypothalamic GHRH receptorsEGRIFTA® (tesamorelin for inje 2010

Pathway

α-MSH analogue → MC1R activation → cAMP elevation → MITF transcription → eumelanin synthesis

GHRH → Pituitary GH release → Liver IGF-1 synthesisFalutz 2007

Downstream effect

Increased melanogenesis, photoprotection, reduced UV sensitivityLangan 2010

Increased GH pulsatility, elevated IGF-1, lipolysis of visceral adipose tissueFalutz 2010

Feedback intact?

Yes — exogenous MC1R agonism does not suppress endogenous α-MSH production

Yes — physiological pulsatility preserved

Origin

Synthetic 13-AA peptidomimetic with norleucine (position 4) and D-phenylalanine (position 7) substitutions for metabolic stabilityChawathe 2026

Synthetic 44-AA GHRH analogue with trans-3-hexenoic-acid modification for stabilityEGRIFTA® (tesamorelin for inje 2010

Antibody development

—

~50% after 26 wks (non-neutralising in most)Sévigny 2018

02Dosage Protocols

Parameter

MT-1

Tesamorelin

Standard dose

16 mg subcutaneous implant

FDA-approved formulation (Scenesse).

2 mg / dayEGRIFTA® (tesamorelin for inje 2010

FDA-approved protocol.

Frequency

Every 60 days

Sustained release implant — no daily administration required.

Once daily (morning or pre-sleep)

Aligns with natural GH pulse.

Evidence basis

Phase 3 RCT / FDA-approved orphan drug

RCT / FDA-approvedFalutz 2007 Falutz 2010

Indication

Erythropoietic protoporphyria (EPP)

Narrow FDA approval — not licensed for cosmetic tanning.

—

Duration

Seasonal use (spring–autumn typical)

Aligned with peak UV exposure months.

12–52 weeks

VAT returns within months of stopping.

Route

Subcutaneous implant — upper arm or abdomen

—

Stability

Norleucine/D-Phe substitutions enhance peptidase resistance

Modified structure vs endogenous α-MSH (Met⁴, L-Phe⁷).

—

Lower / starter dose

—

1 mg / dayFalutz 2010

1 mg still produces significant IGF-1 elevation.

Reconstitution

—

Sterile water per labeling

Preserved at 2–8 °C after reconstitution.

Timing

—

Empty stomach, pre-sleep preferred

Half-life

—

~26 min (plasma)EGRIFTA® (tesamorelin for inje 2010

Modified vs native GHRH (7 min t½).

03Metabolic / Fat Loss Evidence

Parameter

MT-1

Tesamorelin

Primary fat target

—

Visceral adipose tissue (VAT) — abdominal

Quantified reduction

—

15–20% VAT ↓Falutz 2010

By CT at 26 weeks (Falutz et al., NEJM).

IGF-1 impact

—

+66 ng/mL (2 mg dose) · +81% mean elevationFalutz 2007

Effect on lean mass

—

Modest lean mass preservation / slight increase

Insulin sensitivity

—

Neutral to slight impairment (monitor HbA1c)Clarke 2018

Triglycerides

—

Significant TG reduction noted in Phase 3Falutz 2010

Glucose metabolism

—

Generally neutral; 4.5% HbA1c elevation riskClarke 2018

Effect reversibility

—

VAT returns within months of stopping

Key publication

—

Falutz et al. NEJM 2007 · Falutz JCEM 2010 · FDA approval 2010Falutz 2007 Falutz 2010 EGRIFTA® (tesamorelin for inje 2010

04Side Effects & Safety

Parameter

MT-1

Tesamorelin

Nausea

Common (>10%) — mild, transient

—

Implant site reaction

Erythema, bruising, tenderness at insertion site

—

Hyperpigmentation

Generalised tanning (therapeutic effect), darkening of freckles/neviLangan 2010 Habbema 2017

Expected melanogenic response — complicates pigmented lesion surveillance.

—

Melanocytic changes

Rapid pigmentation of existing nevi; new melanocytic lesions reported with unregulated useHabbema 2017

Requires dermatologic monitoring; theoretical melanoma concern with chronic stimulation.

—

Headache

Occasional (MC1R-independent melanocortin effects)

—

Photosensitivity (paradoxical)

Rare phototoxic reactions despite melanin increase

—

Contamination risk (unregulated)

Impurity, infection, blood-borne virus transmission from illicit melanotan productsLangan 2010 Habbema 2017

Applies to internet/gym-sourced 'melanotan' — not FDA-approved Scenesse.

—

Injection site reaction

—

Erythema, pruritus, redness (common)

Fluid retention / Edema

—

Peripheral edema, arthralgia, carpal tunnel (GH-axis effect)

Glucose intolerance

—

HbA1c ↑ in 4.5% vs 1.3% placebo; HbA1c ≥6.5% hazard OR 3.3Clarke 2018

IGF-1 elevation

—

Dose-dependent; supraphysiological levels = discontinue

Cancer risk

—

Contraindicated in active malignancy (GH/IGF-1 axis); theoretical tumour growth riskEGRIFTA® (tesamorelin for inje 2010

Antibody formation

—

~50% at 26 weeks; non-neutralising in most; rare hypersensitivity (<1%)Sévigny 2018

GI symptoms

—

Nausea, diarrhea (mild, transient)

Pregnancy / OB

—

ContraindicatedEGRIFTA® (tesamorelin for inje 2010

Absolute Contraindications

MT-1

·Hypersensitivity to afamelanotide or excipients
·Hepatic impairment (no safety data)
·Renal impairment (no safety data)

Tesamorelin

·Active malignancy or history of treated cancer
·Pregnancy
·Hypersensitivity to tesamorelin or mannitol
·Disruption of hypothalamic-pituitary axis (trauma, tumour, radiation)

Relative Contraindications

MT-1

·History of melanoma or atypical nevi (melanocortin receptor stimulation concern)Habbema 2017
·Pregnancy/lactation (insufficient data)
·Photosensitive dermatoses (other than EPP)

Tesamorelin

·Untreated diabetes (monitor HbA1c)
·Severe carpal tunnel syndrome
·Acute critical illness

05Administration Protocol

Parameter

MT-1

Tesamorelin

1. Implant insertion

Performed by trained healthcare provider. Sterile technique. Small incision in upper arm (triceps) or lower abdomen using trocar. 16 mg rod (4 mm × 1.5 cm) inserted subcutaneously.

Add 2.1 mL sterile water to 2 mg lyophilised vial. Roll gently — do not shake. Solution should be clear.

2. Site care

Pressure applied post-insertion. Sterile dressing × 24 hrs. Avoid strenuous activity for 24–48 hrs to prevent extrusion.

Subcutaneous — abdomen preferred. Rotate sites (avoid same spot within 2 cm). Avoid navel and waistband area.

3. Release kinetics

Slow biodegradable polymer matrix releases afamelanotide over 60 days, maintaining therapeutic plasma levels without daily dosing.

Once daily. Preferred: evening, 2–3 hrs post-meal, before sleep — aligns with natural GH secretion pulse.

4. Repeat dosing

New implant every 60 days during high UV season (spring–autumn in temperate climates). Rotate implant sites to avoid scarring.

Lyophilised: room temp, light-protected. Reconstituted: refrigerate 2–8 °C, use within 21 days.

5. Monitoring

Baseline and periodic dermatologic exams to document pigmented lesions. Patient education on self-examination for new/changing nevi.

27–31G, 4–8 mm insulin syringe. Pinch skin, 45° angle for lean individuals.

06Stack Synergy

MT-1

— no documented stacks

Tesamorelin

+ Ipamorelin

Strong

View Ipamorelin →

Tesamorelin (GHRH analogue) and ipamorelin (GHRP / ghrelin mimetic) act on two distinct receptor systems to amplify GH release synergistically — GHRH receptor + ghrelin receptor. This dual-axis stimulation produces a more robust, sustained GH pulse than either alone while maintaining physiological pulsatility. Ipamorelin is highly selective with minimal cortisol or prolactin elevation, making it the preferred GHRP pairing.

Tesamorelin: 2 mg SQ · evening
Ipamorelin: 200–300 mcg SQ · same injection
Frequency: Once daily, pre-sleep
Primary benefit: Maximal GH pulsatility, fat loss, recovery, sleep quality

Raun 1998