Side-by-side · Research reference

MazdutidevsThymalin

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

APhase 3HUMAN-REVIEWED19/62 cited

BHuman-MechanisticAUTO-DRAFTED12/40 cited

Mazdutide

GLP-1/Glucagon Dual Agonist · Oxyntomodulin Analogue · Phase 3

9 mgWeekly doseJi 2026

12.4%Weight lossAzam 2026

Phase 3Status (China)

SQ · Abdomen · Once WeeklyJi 2026

Thymalin

Immune restorer · Russian peptide bioregulator

5–10 mgPer cycle doseKhavinson 2002

HumanMechanisticKhavinson 2002

HoursHalf-life (est)

IM · Daily for 5–10 days · 1-2×/year

01Mechanism of Action

Parameter

Mazdutide

Thymalin

Primary target

GLP-1 receptor and glucagon receptorAbdul 2026 Elmendorf 2026

T-cell precursors + thymus-axis maturation pathwayKhavinson 2002

Pathway

Dual agonism: GLP-1R → satiety, insulin secretion, gastric emptying delay; GCGR → hepatic lipolysis, energy expenditure, thermogenesisElmendorf 2026 Abulehia 2026

Modulation of T-cell differentiation + thymic hormone restoration in age-involuted thymusKhavinson 2002

Downstream effect

Weight loss via appetite suppression (GLP-1 axis) and increased energy expenditure (glucagon axis); improved glycemic control in T2D

Restored T-cell populations, improved immune surveillance, reduced infection rates in elderlyKhavinson 2002

Feedback intact?

Yes — physiological receptor-mediated signaling preserved

—

Origin

Synthetic oxyntomodulin analogue — endogenous peptide with dual GLP-1/glucagon activity

Polypeptide fraction isolated from calf thymus extractKhavinson 2002

Antibody development

—

02Dosage Protocols

Parameter

Mazdutide

Thymalin

Phase 2 studied dose

9 mg / weekJi 2026

Highest efficacy dose in obesity trial (BMI ≥30 kg/m²).Ji 2026

—

Frequency

Once weeklyJi 2026 Luo 2026

Once daily during cycle

Route

SubcutaneousJi 2026

—

Dose escalation

3 mg → 6 mg → 9 mg (titration schedule in trials)

Gradual escalation to minimize GI side effects.

—

Evidence basis

Phase 2 RCT / Phase 3 ongoingJi 2026 Luo 2026

Russian clinical + in vitroKhavinson 2002

Duration (trials)

24–48 weeks

—

Population

Non-diabetic adults BMI ≥30 kg/m² or ≥27 kg/m² with comorbidities

—

Phase 3 comparator

Semaglutide 1 mg/week (DREAMS-3 trial)Luo 2026

—

Standard dose

—

5–10 mg / day IM × 5–10 daysKhavinson 2002

Lower / starter dose

—

2.5 mg / day

Duration

—

5–10 day cycles, 1–2× per year

Reconstitution

—

Saline or bacteriostatic water

Timing

—

Morning preferred

Half-life

—

Hours (estimated)

03Metabolic / Fat Loss Evidence

Parameter

Mazdutide

Thymalin

Percentage body weight loss

12.4% (pooled meta-analysis, 9 mg dose)

95% CI: -16.15% to -8.68%, random-effects model.Azam 2026

—

Absolute weight loss

9.8 kg (mean)Azam 2026

95% CI: -13.15 to -6.37 kg.Azam 2026

—

Responder rate (≥10% loss)

Not explicitly reported in available abstracts

—

Mechanism

Appetite suppression (GLP-1) + energy expenditure (glucagon)Elmendorf 2026

—

BMI reduction

Significant reduction in Chinese adults BMI ≥30 kg/m²Ji 2026

—

Visceral fat

Expected benefit from glucagon-mediated lipolysis (not quantified in abstracts)

—

Glycemic improvement

HbA1c reduction in T2D cohort (Phase 3 DREAMS-3)

—

Comparator efficacy

Head-to-head vs semaglutide 1 mg (Phase 3 pending publication)Luo 2026

—

Key publications

Ji et al. Med 2026 · Azam et al. Diab Obes Metab 2026 · Luo et al. Contemp Clin Trials 2026

—

04Side Effects & Safety

Parameter

Mazdutide

Thymalin

Gastrointestinal symptoms

Nausea, vomiting, diarrhea (most common, GLP-1 effect)

—

Injection site reactions

Erythema, pruritus, local discomfort

—

Hypoglycemia

Low risk in non-diabetic cohort; monitor in T2D with insulin or sulfonylureas

—

Cardiovascular effects

Increased heart rate (glucagon effect, transient)

—

Pancreatitis risk

Theoretical (incretin class effect); monitor amylase/lipase if abdominal pain

—

Thyroid C-cell tumors

Black box warning for GLP-1 class (rodent data); human relevance unclear

—

Gallbladder disease

Cholelithiasis, cholecystitis (rapid weight loss effect)

—

Tolerability

Generally well-tolerated; GI effects diminish with dose titration

—

Injection site reaction

—

Mild erythema at IM site

Allergic reaction

—

Rare hypersensitivity to bovine-derived polypeptide

Autoimmune flare

—

Theoretical risk in active autoimmune disease

Long-term safety

—

Limited Western data

Pregnancy / OB

—

Avoid

Absolute Contraindications

Mazdutide

·Personal or family history of medullary thyroid carcinoma
·Multiple endocrine neoplasia syndrome type 2 (MEN 2)
·Hypersensitivity to mazdutide or excipients
·Pregnancy

Thymalin

·Pregnancy / breastfeeding
·Bovine protein hypersensitivity

Relative Contraindications

Mazdutide

·History of pancreatitis
·Severe gastroparesis or GI motility disorders
·Diabetic retinopathy (monitor, risk of worsening with rapid glycemic change)
·Renal impairment (limited data, use with caution)

Thymalin

·Active autoimmune disease
·Concurrent immunosuppressant therapy

05Administration Protocol

Parameter

Mazdutide

Thymalin

1. Preparation

Supplied as pre-filled pen or reconstituted vial (per manufacturer instructions). Inspect solution — should be clear, colorless to pale yellow. Discard if cloudy or particulate matter present.

Add 1–2 mL saline or bacteriostatic water per 10 mg vial.

2. Injection site

Subcutaneous — abdomen preferred, also thigh or upper arm. Rotate sites weekly. Avoid areas with scarring, moles, or active inflammation.

Intramuscular — deltoid or gluteal. Rotate sites.

3. Timing

Once weekly, same day each week. May be taken with or without food. If dose missed, administer within 3 days; if >3 days, skip and resume next scheduled dose.

Morning preferred during cycle.

4. Storage

Refrigerate 2–8 °C. Do not freeze. May be kept at room temperature (<25 °C) for up to 14 days if needed. Protect from light.

Lyophilised: refrigerate, light-protected. Reconstituted: use immediately.

5. Needle technique

Use supplied needle or compatible insulin syringe (if reconstituting). Pinch skin, inject at 90° angle. Hold 5–10 seconds before withdrawing needle to prevent leakage.

23–25G, 25–38 mm IM needle.

06Stack Synergy

Mazdutide

— no documented stacks

Thymalin

+ Thymosin α-1

Moderate

View Thymosin α-1 →

Thymalin is a polypeptide complex; Thymosin α-1 is a single purified peptide. Both target the thymus-axis but at different levels — Thymalin restores broad thymic signaling; Tα-1 provides a specific molecular activator. Anecdotally combined for elderly immune support.

Thymalin: 5–10 mg IM · daily × 7 days
Thymosin α-1: 1.6 mg SQ · 2× weekly during the cycle
Primary benefit: Broad thymic restoration + targeted immune activation

Khavinson 2002 Camerini 2001