≥99% HPLCIntranasal spray

PHDP5 (Intranasal Spray)

Name: PHDP5 (Intranasal Spray)
Brand: Dripfy
Availability: InStock

What it is?

PHDP5 is a synthetic 12-amino-acid peptide (dodecapeptide) that mirrors residues 560–571 of the pleckstrin-homology (PH) domain of dynamin 1, a protein essential for recycling synaptic vesicles at nerve endings. It was developed by researchers at the Okinawa Institute of Science and Technology (OIST) and is investigated for protecting synaptic function in Alzheimer's disease models. All published data are preclinical (brain-slice and mouse studies); PHDP5 has not been tested in humans.

Dripfy Advantage

Targeted synaptic mechanism: Acts as a dominant-negative inhibitor of the dynamin–microtubule interaction, keeping dynamin available for synaptic vesicle endocytosis.
Tau-pathway relevance: In Alzheimer's synapse models, excess soluble tau assembles new microtubules that sequester dynamin; PHDP5 counteracted this and preserved vesicle recycling and neurotransmission.
Nose-to-brain research concept: In mouse studies, a modified form (linked to a cell-penetrating peptide) was given intranasally, crossed the blood–brain barrier and reached the hippocampus.
Peer-reviewed research basis: Mechanism described in eLife (Hori et al., 2022); in-vivo learning and memory data published in Brain Research (Chang et al., 2024).

Clinical Applications & Therapeutic Potential

Learning and memory (preclinical): Intranasal administration restored spatial learning and memory in two Alzheimer's model mouse strains (Tau609 and 3xTg-AD) to a level comparable with healthy controls in the Morris water maze.
Synaptic resilience research: Investigated for preserving synaptic vesicle endocytosis and excitatory neurotransmission under tau-related stress.
Early-stage neurodegeneration research: The researchers emphasise that PHDP5 cannot cure Alzheimer's disease; any benefit would be expected to slow decline only when applied at a relatively early stage.
Development status: No human clinical trials have been conducted; PHDP5 is not an approved medicine for any indication.

Composition & Formulation

Peptide: PHDP5 — synthetic dodecapeptide derived from the dynamin 1 PH domain (residues 560–571)
Format: Intranasal spray
Purity: ≥99% by HPLC/MS
Supervision: Physician-directed use only

€1,225

Order by email

Submit an enquiry and we arrange the consultation, physician review and shipping. Physician recommendation required; not medical advice.

Purity: ≥99%
Form: Intranasal spray
Download Certificate of Analysis: Certificate of Analysis available on request

Important medical notice

A physician recommendation is mandatory before use.
The information on this website is educational only and is not medical advice, diagnosis, or treatment.
Always consult a qualified physician before starting any peptide.
Dosing is individualised and determined by your treating physician.

Peptide Practice Guide

Each card summarises what the peptide is studied for and its evidence strength. It is not a recommendation. Dosing and suitability are decided by your physician.

PHDP5 (Intranasal Spray)

Synthetic dynamin-1-derived peptide (dynamin–microtubule interaction inhibitor) · Intranasal spray

D· Preliminary evidence

PHDP5 is a synthetic 12-amino-acid peptide matching residues 560–571 of the pleckstrin-homology domain of dynamin 1, a protein required for synaptic vesicle endocytosis. In Alzheimer's synapse models, excess soluble tau assembles new microtubules that sequester dynamin, slowing vesicle recycling and weakening neurotransmission; PHDP5 acts as a dominant-negative inhibitor of the dynamin–microtubule interaction and attenuated these deficits in brain-slice experiments. In two Alzheimer's model mouse strains, a cell-penetrating-peptide-modified form given intranasally reached the hippocampus and restored spatial learning and memory. No human data exist.

Studied use areas

Synaptic vesicle recycling and neurotransmission (preclinical concept)
Tau-related synaptic dysfunction in Alzheimer's disease models
Spatial learning and memory endpoints (mouse data)
Intranasal nose-to-brain peptide delivery research

Safety & status

No human safety or tolerability data; not an approved medicine
Studied in animals only, partly as a modified (cell-penetrating, fluorescently labelled) research form — findings may not transfer to this formulation or to humans
Nasal application — follow the supervising physician's instructions and avoid contact with the eyes
Requires physician assessment before any use, particularly in people with neurological conditions

⚕ Clinical note: This is educational information only and not medical advice. PHDP5 is an early-stage research peptide supported only by laboratory and mouse studies; it is not a treatment for Alzheimer's disease or memory loss. Any use must be assessed and supervised by a treating physician, who determines suitability on an individual basis.

Evidence: Preclinical — brain-slice and mouse data only, no human studies · References: Hori T et al. Microtubule assembly by tau impairs endocytosis and neurotransmission via dynamin sequestration in Alzheimer's disease synapse model. eLife. 2022;11:e73542; Chang CJ, Taoufiq Z et al. The microtubule-dynamin binding inhibitor peptide PHDP5 rescues spatial learning and memory deficits in Alzheimer's disease model mice. Brain Research. 2024. doi:10.1016/j.brainres.2024.148987; OIST press release (20 June 2024): Damage to synapses caused by Alzheimer's disease reversed