Side-by-side · Research reference

DihexavsVIP

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

BPhase 3HUMAN-REVIEWED9/42 cited

Dihexa

Angiotensin IV Analogue · Pre-Clinical

Pre-clinicalDevelopment stage

Rodent onlyEvidence basisBenoist 2014

HGF/c-MetTarget systemWright 2015

Not established — animal studies only

VIP

Neuropeptide · VPAC1/VPAC2 Agonist · Emergency Use Authorization (COVID-19 ARDS)

IntravenousPrimary routeBrown 2023

ARDSLead indicationUdupa 2025

Phase 3Development stage

IV infusion · Inhaled (investigational)Brown 2023 Boesing 2022

01Mechanism of Action

Parameter

Dihexa

VIP

Primary target

c-Met receptor (HGF receptor tyrosine kinase)

VPAC1 and VPAC2 G-protein-coupled receptorsUdupa 2025

Pathway

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

VIP → VPAC1/VPAC2 activation → cAMP elevation → Pulmonary vasodilation + epithelial protection

Downstream effect

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

Anti-inflammatory cytokine modulation, alveolar-capillary membrane stabilization, pulmonary smooth muscle relaxation, reduced neutrophil infiltration

Feedback intact?

—

Yes — exogenous VIP acts as physiological agonist

Origin

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

Endogenous 28-amino-acid neuropeptide; synthetic analogue (aviptadil) identical to natural VIP

Antibody development

—

02Dosage Protocols

Parameter

Dihexa

VIP

Human dosing

Not established — no human trials

—

Animal studies

Mouse/rat models only — dosing not translatable to humans

—

Evidence basis

Pre-clinical / Rodent models

Phase 3 RCT (TESICO)Brown 2023

816-patient randomized controlled trial in COVID-19 ARDS.

Clinical status

No Phase 1, 2, or 3 trials published

—

Intravenous (ARDS protocol)

—

60–90 mcg/kg/day via continuous infusion

TESICO trial protocol for COVID-19 ARDS.

Infusion duration

—

12-hour continuous IV infusion dailyBrown 2023

Inhaled (investigational)

—

Variable dosing under clinical trial protocolsBoesing 2022

Delivered via nebulizer for direct pulmonary deposition.

Treatment duration

—

3–14 days (acute ARDS)

Reconstitution

—

Lyophilized powder reconstituted with sterile diluent per protocol

Half-life

—

~2 minutes (plasma)

Rapid clearance necessitates continuous infusion.

04Side Effects & Safety

Parameter

Dihexa

VIP

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

—

Hypotension

—

Transient vasodilation-related blood pressure drop

Tachycardia

—

Reflex tachycardia secondary to vasodilation

Infusion site reactions

—

Erythema, phlebitis (IV administration)

GI symptoms

—

Nausea, diarrhea (VIP is endogenous GI peptide)

Overall tolerability

—

Well-tolerated in Phase 3 trials; adverse event profile comparable to placebo

Absolute Contraindications

Dihexa

·Not approved for human use — research compound only

VIP

·Known hypersensitivity to aviptadil or formulation components

Relative Contraindications

Dihexa

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

VIP

·Severe hypotension or shock states (monitor blood pressure)
·Pregnancy — insufficient safety data

05Administration Protocol

Parameter

Dihexa

VIP

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.

Reconstitute lyophilized aviptadil powder with sterile diluent per manufacturer protocol. Inspect solution for particulates — should be clear and colorless.

2. Legal status

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

Administer as continuous 12-hour intravenous infusion via central or peripheral line. Use infusion pump for precise dosing (60–90 mcg/kg/day divided over infusion duration).

3. Monitoring

—

Monitor blood pressure, heart rate, and oxygenation continuously during first infusion. Assess for hypotension and adjust infusion rate if needed.

4. Inhaled protocol (investigational)

—

Deliver via jet or mesh nebulizer per clinical trial protocol. Patient seated upright, normal tidal breathing for 10–15 minutes.

5. Storage

—

Store lyophilized powder at 2–8 °C, light-protected. Reconstituted solution: use immediately or within 24 hours if refrigerated.