Side-by-side · Research reference

DihexavsFollistatin-344

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

AAnimal-StrongHUMAN-REVIEWED7/28 cited

BHuman-MechanisticHUMAN-REVIEWED4/58 cited

Dihexa

Angiotensin IV Analogue · Pre-Clinical

Pre-clinicalDevelopment stage

Rodent onlyEvidence basisBenoist 2014

HGF/c-MetTarget systemWright 2015

Not established — animal studies only

Follistatin-344

Myostatin/Activin Antagonist · Research Use

15–25%FST/MSTN ratio ↑

344 AACirculating isoform

ResearchPhase status

Research · No approved protocol

01Mechanism of Action

Parameter

Dihexa

Follistatin-344

Primary target

c-Met receptor (HGF receptor tyrosine kinase)

Myostatin (MSTN/GDF-8) and Activin A

Pathway

HGF/c-Met receptor activation → downstream signaling cascade → synaptogenesis and dendritic arborization

FST-344 binds MSTN/Activin → prevents ActRIIB receptor engagement → disinhibits muscle anabolism

Downstream effect

Induction of dendritic arborization, synapse formation, neurogenesis, and neuroprotection in rodent models

Elevated follistatin/myostatin ratio, increased muscle protein synthesis, attenuated muscle atrophy signalingJeong 2026

Feedback intact?

—

Yes — indirect antagonist, preserves endogenous regulation

Origin

Small-molecule angiotensin IV analogue designed to activate HGF/c-Met systemWright 2015

Endogenous glycoprotein, 344-AA isoform lacking heparin-binding domain (vs FST-315)

Antibody development

—

Not documented in available trials (endogenous protein)

02Dosage Protocols

Parameter

Dihexa

Follistatin-344

Human dosing

Not established — no human trials

—

Animal studies

Mouse/rat models only — dosing not translatable to humans

—

Evidence basis

Pre-clinical / Rodent models

Human observational / biomarker studies

Clinical status

No Phase 1, 2, or 3 trials published

—

Clinical protocol

—

None — no approved dosing regimen

Follistatin-344 measured as endogenous biomarker, not administered exogenously in cited trials.

Research context

—

Endogenous modulation via exercise + nutrition

Resistance training + EAA intake elevated FST/MSTN ratio by 15–25% in 12-week RCT (older women).

Half-life

—

Not established

Circulating isoform; lacks tissue-binding domain of FST-315.

03Metabolic / Fat Loss Evidence

Parameter

Dihexa

Follistatin-344

Primary target

—

Muscle mass preservation, not direct lipolysis

Indirect fat effect

—

Increased lean mass → elevated resting metabolic rate

Not primary mechanism. Muscle-sparing during deficit.

Clinical evidence

—

Lorcaserin trial (6 mo) showed no MAFI axis changes during fat lossRamirez-Cisneros 2026

Suggests follistatin not primary driver of fat loss in weight-reduction interventions.

GLP-1RA studies

—

Liraglutide (35 days) — no significant MAFI axis modulation despite fat/lean changes

04Side Effects & Safety

Parameter

Dihexa

Follistatin-344

Human safety data

None available — no human clinical trials

—

Theoretical c-Met risks

c-Met receptor activation has been implicated in tumorigenesis; unknown cancer risk profile

—

Pre-clinical tolerability

Not systematically reported in available studies

—

Clinical safety data

—

None — no human exogenous administration trials in literature

Theoretical risks

—

Excessive myostatin inhibition → muscle overgrowth, impaired glucose tolerance

Based on myostatin-null animal models and clinical myostatin inhibitor trials.

Endogenous elevation (exercise)

—

No adverse effects reported in 12-week resistance + EAA trials

Cancer risk (theoretical)

—

Myostatin inhibition may promote tumor growth in malignancy (preclinical data)

Regulatory status

—

Not approved for human use — research peptide only

Absolute Contraindications

Dihexa

·Not approved for human use — research compound only

Follistatin-344

·Active malignancy
·No approved protocol — research use only

Relative Contraindications

Dihexa

·Theoretical contraindication: active or history of malignancy (c-Met pathway involvement in cancer)

Follistatin-344

·Insulin resistance / Type 2 diabetes (monitor glucose)
·Pregnancy / lactation (unknown safety profile)

05Administration Protocol

Parameter

Dihexa

Follistatin-344

1. Human administration

No established protocol. Dihexa has not been tested in human subjects. Animal studies used various routes (typically subcutaneous or intraperitoneal in rodents) not translatable to clinical use.

Follistatin-344 is not approved for human administration. All cited studies measure endogenous serum follistatin as a biomarker, not as an exogenous therapeutic agent.

2. Legal status

Pre-clinical research compound. Not approved by FDA or any regulatory authority for human use.

Resistance exercise combined with essential amino acid (EAA) supplementation elevated the follistatin/myostatin ratio by 15–25% in 12-week randomized trials. Protein intake (1.2–1.5 g/kg/day) synergizes with training to upregulate endogenous follistatin.

3. Measurement context

—

Serum follistatin and follistatin/myostatin ratio are used diagnostically in sarcopenia screening and as biomarkers of muscle anabolic balance in clinical trials.

4. Research consideration

—

Gene therapy and recombinant follistatin delivery are under preclinical investigation for muscular dystrophy and sarcopenia. No human safety or efficacy data for exogenous FST-344 administration.

06Stack Synergy

Dihexa

— no documented stacks

Follistatin-344

+ BPC-157

Multi-pathway

View BPC-157 →

Follistatin-344 (myostatin antagonist) and BPC-157 (tissue repair peptide) address complementary pathways in muscle recovery. FST-344 promotes muscle protein synthesis by disinhibiting myostatin signaling, while BPC-157 accelerates healing of tendons, ligaments, and microtears via angiogenesis and collagen synthesis. Combined, they may support both hypertrophy and structural repair during high-volume training or injury recovery.

Follistatin-344: No approved protocol — endogenous modulation via resistance exercise + EAA
BPC-157: 250–500 mcg SQ · twice daily · near injury site or systemic
Duration: 4–8 weeks
Primary benefit: Muscle hypertrophy + accelerated soft tissue repair

+ TB-500

Moderate

View TB-500 →

TB-500 (thymosin beta-4 fragment) promotes cell migration, angiogenesis, and anti-inflammatory signaling in muscle and connective tissue. Follistatin-344's anabolic signaling may synergize with TB-500's regenerative effects during muscle damage or overtraining, particularly in older adults where both myostatin inhibition and tissue repair are rate-limiting.

Follistatin-344: Endogenous upregulation (resistance training + protein)
TB-500: 2–5 mg SQ · twice weekly · loading phase 4 weeks, then maintenance
Frequency: Twice weekly TB-500, daily training stimulus for FST
Primary benefit: Enhanced recovery, reduced inflammation, muscle growth support