Side-by-side · Research reference

HGH Fragment 176-191vsThymosin α-1

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

AAnimal-StrongHUMAN-REVIEWED28/59 cited

BPhase 3HUMAN-REVIEWED8/39 cited

HGH Fragment 176-191

GH Fragment · Pre-Clinical

50%Weight gain reductionNg 2000

~26 minHalf-life (est.)

No IGF-1 ↑GH axis impact

SQ · IP (animal) · Oral (tested)

Thymosin α-1

Immune modulator · Approved (some countries)

1.6 mgPer doseIyer 2007

Phase 3Evidence levelIyer 2007 Camerini 2001

~2 hrHalf-life

SQ · 2× weekly · 6+ months for chronic indications

01Mechanism of Action

Parameter

HGH Fragment 176-191

Thymosin α-1

Primary target

Beta-3 adrenergic receptors on adipocytesHeffernan 2001

Toll-like receptor 9 (TLR9) + T-cell maturation pathwayCamerini 2001

Pathway

Fragment → β3-AR upregulation → Enhanced lipolytic sensitivityHeffernan 2001

TLR9 activation → ↑ IFN-α + IL-2 + IFN-γ → enhanced T-cell function + dendritic cell maturationIyer 2007

Downstream effect

Increased lipolysis and beta-3 AR mRNA expression without IGF-1 axis activation

Restored T-cell function, improved viral clearance, anti-tumour adjuvant effectsIyer 2007

Feedback intact?

N/A — does not interact with GH/IGF-1 axis

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Origin

Synthetic peptide derived from hGH residues 176-191; AOD9604 includes N-terminal tyrosine (177-191)Cox 2015

Synthetic 28-AA peptide identical to natural Tα-1 isolated from thymus extractCamerini 2001

Antibody development

Not reported in available studies

—

02Dosage Protocols

Parameter

HGH Fragment 176-191

Thymosin α-1

Animal dose (oral)

500 mcg/kg body weightNg 2000

Obese Zucker rats, 19 days.

—

Animal dose (IP)

Not specified (14-day chronic administration)Heffernan 2001

Obese mice, daily IP injection.

—

Human equivalent dose

Not established — no published human RCTs

—

Frequency

Once daily (animal models)

2× weekly (Mon/Thu typical)

Evidence basis

Animal studies only

Phase 3 + approved (35+ countries as Zadaxin)Iyer 2007

Duration tested

14–19 daysHeffernan 2001 Ng 2000

—

Detection window

50 pg/mL LOD in urine; stable metabolite extends detectionCox 2015

WADA-banned; anti-doping testing available.

—

Oral bioavailability

Demonstrated efficacy in animal oral administrationNg 2000

Potential for oral therapeutic development.

—

Standard dose (HBV/HCV)

—

1.6 mg SQ 2× weekly × 6–12 monthsIyer 2007

Lower / starter dose

—

0.8 mg per injection

Duration

—

6–12 months for chronic indications

Reconstitution

—

Sterile water for injection per vial label

Timing

—

No specific time

Half-life

—

~2 hours plasma; tissue effect days

03Metabolic / Fat Loss Evidence

Parameter

HGH Fragment 176-191

Thymosin α-1

Primary fat target

Adipose tissue (general) — beta-3 AR mediated lipolysisHeffernan 2001

—

Weight gain reduction

50% reduction vs control (15.8 ± 0.6 g vs 35.6 ± 0.8 g)Ng 2000

Obese Zucker rats, 19 days oral administration.

—

Body fat reduction

Significant decrease in body weight and body fat in obese mice (14 days)Heffernan 2001

—

Lipolytic activity

Increased adipose tissue lipolytic activityNg 2000

Direct measurement in treated animals.

—

Beta-3 AR expression

Upregulated β3-AR mRNA in obese mice to lean-comparable levelsHeffernan 2001

—

Insulin sensitivity

No adverse effect — euglycemic clamp confirmedNg 2000

Contrasts with intact hGH diabetogenic effects.

—

IGF-1 impact

No elevation — fragment does not activate GH/IGF-1 axis

—

Beta-3 AR dependency

Effect abolished in β3-AR knockout miceHeffernan 2001

Confirms β3-AR as primary mechanism.

—

Route of administration

Efficacy demonstrated via oral and IP routesNg 2000 Heffernan 2001

—

Human evidence

None published — pre-clinical only

—

04Side Effects & Safety

Parameter

HGH Fragment 176-191

Thymosin α-1

Insulin sensitivity

No adverse effects observed in euglycemic clamp (animal)Ng 2000

—

GH/IGF-1 axis

No activation — avoids diabetogenic effects of full GHNg 2000

—

Human safety data

Not available — no published human trials

—

WADA status

Banned as performance-enhancing drugCox 2015

—

Metabolic profile

Six metabolites identified; CRSVEGSCG most stableCox 2015

Detection window implications for doping control.

—

Injection site reaction

—

Erythema, mild discomfort

GI symptoms

—

Rare nausea

Fatigue

—

Common during initial weeks

Fever / flu-like

—

Mild interferon-like response possible

Autoimmune

—

Theoretical risk; caution in active autoimmune disease

Cancer risk

—

No signal — used as adjuvant in oncology

Pregnancy / OB

—

Avoid

Absolute Contraindications

HGH Fragment 176-191

·Competitive athletes (WADA-banned)Cox 2015

Thymosin α-1

·Pregnancy / breastfeeding
·Hypersensitivity to peptide
·Concurrent immunosuppressant therapy (transplant patients)

Relative Contraindications

HGH Fragment 176-191

·Absence of human safety data — experimental use only

Thymosin α-1

·Active autoimmune disease
·Severe immunocompromised state without supervision

05Administration Protocol

Parameter

HGH Fragment 176-191

Thymosin α-1

1. Route

Subcutaneous injection primary route in research context. Oral administration demonstrated efficacy in animal models at 500 mcg/kg.

Add 1 mL sterile water per 1.6 mg vial → 1.6 mg/mL.

2. Frequency

Once daily dosing used in animal studies. Timing not specified; GH-independent mechanism suggests flexibility.

SQ — abdomen, thigh, or upper arm. Rotate sites.

3. Duration

Animal protocols: 14–19 days. Human duration not established — no published trials.

2× weekly, e.g. Monday + Thursday.

4. Storage

Lyophilized peptide storage per standard peptide protocols. Metabolite stability suggests refrigerated reconstituted solution viable.

Lyophilised: refrigerate. Reconstituted: refrigerate, use within 24 h.

5. Detection

Detectable in urine via SPE-LC-MS at 50 pg/mL LOD. Extended detection window via stable metabolite CRSVEGSCG.Cox 2015

27–31G, 4–8 mm insulin syringe.