Dihexa Peptide Guide: HGF/c-Met Signaling, Synaptogenesis, Neuroplasticity, Cognition, and More.

Dihexa evolved from research into:

ANGIOTENSIN IV — AngIV.

Angiotensin IV is a naturally occurring peptide within the:

RENIN–ANGIOTENSIN SYSTEM.

Most people associate that system with:

blood pressure 

sodium 

aldosterone 

vascular tone 

But the brain has its own:

RENIN–ANGIOTENSIN SIGNALING NETWORK.

And AngIV attracted particular interest because experimental studies associated it with:

LEARNING + MEMORY.

The problem was pharmacology.

Natural peptides often have:

rapid degradation 

limited oral bioavailability 

poor blood-brain-barrier penetration 

Researchers therefore developed:

METABOLICALLY STABILIZED ANALOGS.

Dihexa became one of the most important.

ANGIOTENSIN IV

↓

Procognitive biology identified

↓

Nle¹-ANGIOTENSIN IV

↓

Further molecular modification

↓

Greater:

HYDROPHOBICITY

METABOLIC STABILITY

BRAIN PENETRATION

↓

DIHEXA

↓

Potential:

SYNAPTOGENESIS

COGNITIVE RECOVERY

NEUROPLASTICITY

Again

this is not merely:

“MAKE AngIV LAST LONGER.”

The pharmacology evolved into a molecule with an especially interesting relationship to:

HGF / c-MET SIGNALING.

Historically, Angiotensin IV cognitive effects were attributed to an:

AT4 RECEPTOR SYSTEM.

But the molecular identity of that system became controversial.

One proposed target has been:

IRAP — INSULIN-REGULATED AMINOPEPTIDASE.

Another body of research linked AngIV-derived cognition-enhancing compounds to:

THE HGF / c-MET SYSTEM.

The Dihexa research program ultimately provided strong experimental evidence that at least many of its synaptogenic and procognitive effects depend upon:

HGF → c-MET SIGNALING. 

That distinction matters.

Because Dihexa should not simply be described as:

AN ANGIOTENSIN RECEPTOR DRUG.

Its most compelling mechanistic story is:

HGF MODULATION.

 HGF stands for:

HEPATOCYTE GROWTH FACTOR.

The name can be misleading.

HGF was originally characterized through:

LIVER BIOLOGY.

But HGF signaling exists throughout the body.

It participates in:

tissue repair 

cell survival 

cell migration 

morphogenesis 

neuronal development 

neurite growth 

synaptic biology 

Its primary receptor is:

c-MET

also called:

MET RECEPTOR TYROSINE KINASE.

This is a powerful growth-factor system.

HGF

↓

binds:

c-MET

↓

Receptor activation / phosphorylation

↓

Downstream pathways including:

PI3K / AKT

MAPK / ERK

and other growth/survival networks

↓

Potential:

CELL SURVIVAL

MIGRATION

MORPHOGENESIS

NEURITE GROWTH

SYNAPSE FORMATION

Within the brain, that opens an especially interesting question:

CAN HGF SIGNALING HELP REBUILD LOST NEURAL CONNECTIONS?

Dihexa was developed around exactly that possibility.

This distinction is important.

Experimental work found that Dihexa binds directly and with high affinity to:

HGF.

The reported binding affinity was approximately:

Kd ≈ 6.5 × 10⁻¹¹ M.

Dihexa enhanced HGF-dependent c-Met phosphorylation at HGF concentrations that otherwise produced much weaker signaling.

Importantly, in those experiments:

DIHEXA ALONE DID NOT ROBUSTLY ACTIVATE c-MET IN THE SAME WAY.

Instead, the data support a model in which Dihexa acts as an:

HGF MIMETIC / ALLOSTERIC FACILITATOR

that increases the effectiveness of existing:

HGF → c-MET SIGNALING. 

That is a major mechanistic distinction.

LOW / SUBTHRESHOLD HGF

↓

Limited c-Met activation

Dihexa

↓

Interaction with HGF

↓

HGF signaling becomes more effective

↓

c-MET PHOSPHORYLATION ↑

↓

Potential downstream:

SYNAPTOGENESIS

DENDRITIC REMODELING

PLASTICITY

This suggests Dihexa may behave less like:

A RECEPTOR HAMMER

and more like:

A GROWTH-FACTOR SIGNAL AMPLIFIER.

That is biologically much more interesting.

This is arguably Dihexa's defining feature.

Synaptogenesis means:

FORMATION OF NEW SYNAPSES.

A synapse is the functional connection through which one neuron communicates with another.

Memory is therefore not merely:

A CHEMICAL CONCENTRATION.

Memory requires:

NETWORK CONNECTIVITY.

Experimental Dihexa research demonstrated:

HIPPOCAMPAL SPINOGENESIS

and:

SYNAPTOGENESIS

similar to HGF itself. 

That places the peptide directly into:

STRUCTURAL NEUROPLASTICITY.

Dendritic spines are tiny projections extending from neuronal dendrites.

Many excitatory synapses form on:

THESE SPINES.

They are dynamic.

They can:

appear 

disappear 

enlarge 

shrink 

stabilize 

during:

LEARNING.

So dendritic-spine biology provides a physical bridge between:

MOLECULAR SIGNALING

and:

MEMORY.

DIHEXA

↓

HGF facilitation

↓

c-MET

↓

Neuronal growth / remodeling pathways

↓

DENDRITIC SPINES ↑

↓

SYNAPTIC CONTACTS ↑

↓

Potential:

NETWORK CONNECTIVITY ↑

↓

Potential:

LEARNING + MEMORY IMPROVEMENT

This is a fundamentally different model from:

“INCREASE A NEUROTRANSMITTER AND FEEL MORE FOCUSED.”

It is:

CHANGE THE ARCHITECTURE OF THE NETWORK.

A new dendritic spine is interesting.

But the important question is:

DOES IT BECOME A FUNCTIONAL SYNAPSE?

Research into AngIV-derived compounds has emphasized formation of:

NEW FUNCTIONAL SYNAPTIC CONNECTIONS. 

That distinction matters because:

STRUCTURAL CHANGE WITHOUT FUNCTIONAL INTEGRATION

may not improve cognition.

Again:

MORE STRUCTURE ≠ BETTER NETWORK

unless the network actually:

USES IT.

A useful way to think about Dihexa is:

EXPERIENCE

↓

Neural activity

↓

Potential Dihexa-supported:

HGF / c-MET PLASTICITY

↓

Synaptic remodeling

↓

Connections stabilize

↓

Potential:

MEMORY CONSOLIDATION

This immediately brings us to an important Praxis principle:

PLASTICITY NEEDS DIRECTION.

A more plastic brain is:

MORE CHANGEABLE.

But what it changes into depends partly on:

WHAT THE BRAIN IS DOING.

If a molecule increases:

SYNAPTOGENIC CAPACITY,

then:

cognitive training 

rehabilitation 

learning 

environmental enrichment 

exercise 

adequate sleep 

may become especially relevant.

Why?

Because those experiences provide:

THE PATTERN THE NETWORK IS SUPPOSED TO BUILD.

So:

DIHEXA

without:

LEARNING INPUT

is biologically different from:

DIHEXA + INTENSIVE COGNITIVE ENGAGEMENT.

Again:

BIOLOGY + ENVIRONMENT.

Dihexa was specifically developed as a:

PROCOGNITIVE / ANTIDEMENTIA COMPOUND.

Early work demonstrated activity in:

scopolamine-impaired animals 

aged animals 

spatial-learning paradigms 

The 2013 development paper reported substantial procognitive activity and synaptogenic effects, with Dihexa designed specifically to overcome the metabolic and BBB limitations of earlier AngIV analogs. 

This provides:

FUNCTIONAL PRECLINICAL SUPPORT

for the synaptic mechanism.

Scopolamine blocks:

MUSCARINIC ACETYLCHOLINE RECEPTORS.

Experimentally, this can impair:

LEARNING + MEMORY.

Dihexa improved spatial-learning deficits in scopolamine-treated animals. 

That does not mean Dihexa:

IS CHOLINERGIC REPLACEMENT.

Instead

it suggests sufficient enhancement of network plasticity may help compensate for:

IMPAIRED COGNITIVE SIGNALING.

That is an important distinction.

Dihexa has also shown procognitive effects in:

AGED ANIMAL MODELS.

That is especially interesting because aging can involve:

dendritic-spine loss 

reduced synaptic plasticity 

impaired neurotrophic signaling 

vascular changes 

mitochondrial dysfunction 

inflammation 

So Dihexa's mechanistic fit may be particularly coherent when the problem is:

LOSS OF SYNAPTIC CONNECTIVITY.

Again

not every age-related cognitive problem is:

A SYNAPSE PROBLEM.

Dihexa is frequently associated with:

ALZHEIMER'S DISEASE.

The biological rationale is strong.

Alzheimer's disease involves:

amyloid biology 

tau pathology 

neuroinflammation 

mitochondrial dysfunction 

dendritic loss 

synaptic failure 

neuronal death 

Importantly:

SYNAPTIC DYSFUNCTION OCCURS EARLY.

And cognitive impairment correlates strongly with:

LOSS OF FUNCTIONAL SYNAPTIC CONNECTIONS.

Dihexa therefore asks a different therapeutic question from:

“HOW DO WE REMOVE AMYLOID?”

It asks:

“CAN WE RESTORE THE NETWORK CONNECTIONS THAT COGNITION REQUIRES?”

DISEASE PROCESS

↓

Dendritic spine loss

↓

Synapse loss

↓

Network connectivity ↓

↓

Memory ↓

Dihexa

↓

Potential:

HGF / c-MET SIGNALING ↑

↓

Potential:

SYNAPTOGENESIS ↑

↓

Potential:

NETWORK CONNECTIVITY ↑

↓

Potential:

COGNITIVE FUNCTION ↑

Again

this does not necessarily mean:

THE UNDERLYING DISEASE PROCESS STOPS.

That is a critical distinction.

Suppose a therapy creates:

MORE SYNAPTIC CONNECTIONS.

Cognition improves.

But:

amyloid accumulation continues.

Tau pathology continues.

Neurodegeneration continues.

That therapy may still provide:

REAL FUNCTIONAL BENEFIT.

But it may not be:

DISEASE-MODIFYING.

So we must distinguish:

COGNITIVE RESCUE

from:

DISEASE REVERSAL.

That distinction is especially important with Dihexa.

Research in APP/PS1 mice found that Dihexa improved:

SPATIAL LEARNING + MEMORY.

The study also reported:

increased neuronal-cell measures 

increased synaptophysin expression 

reduced microglial and astrocyte activation 

lower IL-1β and TNF-α 

higher IL-10 

activation of PI3K/AKT signaling 

Blocking PI3K attenuated several of these effects, supporting a role for:

PI3K / AKT

in the downstream response. 

This expands Dihexa's potential biology beyond:

SYNAPSES ALONE.

PI3K / AKT is a major intracellular pathway involved in:

cell survival 

metabolism 

growth 

anti-apoptotic signaling 

plasticity 

A simplified model is:

HGF

↓

c-MET

↓

PI3K

↓

AKT

↓

Potential:

CELL SURVIVAL

PLASTICITY

METABOLIC RESILIENCE

This could partly explain why Dihexa research has shown effects involving:

NEURONAL SURVIVAL + INFLAMMATORY RESPONSE

in addition to:

SPINOGENESIS.

The APP/PS1 study also reported reduced:

MICROGLIAL + ASTROCYTIC ACTIVATION

and shifts in inflammatory cytokines after Dihexa treatment. 

This is interesting.

But Dihexa should not be reclassified as:

AN ANTI-INFLAMMATORY PEPTIDE.

The inflammatory changes may emerge downstream from:

IMPROVED CELLULAR / HGF SIGNALING.

Again:

DOWNSTREAM EFFECT ≠ PRIMARY IDENTITY.

Angiotensin-IV analog development has also included interest in:

PARKINSON'S DISEASE

and motor-network recovery.

The rationale involves:

synaptic connectivity 

neuronal survival 

motor circuitry 

neurotrophic signaling 

Reviews of this research program describe Dihexa as potentially relevant to both memory and motor dysfunction through enhancement of functional synaptic connectivity. 

Again

this remains primarily:

PRECLINICAL / TRANSLATIONAL.

Dihexa has more recently been investigated in an experimental:

HUNTINGTON'S-LIKE RAT MODEL.

A 2024 study using the mitochondrial toxin 3-nitropropionic acid reported investigation of Dihexa/PNB-0408 across:

motor function 

spatial learning 

memory 

histopathology 

because of its prior neuroprotective and procognitive activity in other neurodegenerative models. 

This broadens the research question.

Instead of:

“IS DIHEXA AN ALZHEIMER'S PEPTIDE?”

the more useful question becomes:

“CAN HGF-DEPENDENT SYNAPTIC REPAIR HELP NETWORKS DAMAGED BY DIFFERENT NEURODEGENERATIVE PROCESSES?”

HGF / c-MET biology extends far beyond:

THE BRAIN.

The pathway participates in:

liver regeneration 

wound healing 

cellular migration 

tissue morphogenesis 

development 

angiogenic interactions 

That makes HGF:

A POWERFUL REPAIR SIGNAL.

And that deserves both:

INTEREST

and:

BIOLOGICAL RESPECT.

The same pathway that supports:

REPAIR

can become problematic when growth signaling is:

ABNORMALLY ACTIVATED IN THE WRONG CELL.

c-MET dysregulation is involved in multiple cancers and is sufficiently important that:

c-MET INHIBITORS

have been developed as anticancer therapies. 

This does not establish that:

DIHEXA CAUSES CANCER.

That would be an unsupported conclusion.

The appropriate lesson is:

WHEN A THERAPY INTERSECTS WITH A MAJOR GROWTH-FACTOR PATHWAY, CELLULAR CONTEXT MATTERS.

Healthy tissue:

HGF / c-MET

↓

Repair

↓

Cell survival

↓

Migration

↓

Regeneration

Neural tissue:

HGF / c-MET

↓

Dendritic growth

↓

Synaptogenesis

↓

Potential:

RECOVERY

But abnormal proliferative tissue may use:

THE SAME PATHWAY

for very different purposes.

Again:

MECHANISM IS NOT MORALLY GOOD OR BAD.

It depends on:

THE BIOLOGICAL ENVIRONMENT.

That is the same conceptual principle we discussed with:

EPITALON + TELOMERASE.

Two bad conclusions are possible.

OVERSIMPLIFICATION 1

“c-MET IS INVOLVED IN CANCER, SO DIHEXA CAUSES CANCER.”

Not established.

OVERSIMPLIFICATION 2

“DIHEXA IS A BRAIN PEPTIDE, SO c-MET ONCOLOGY IS IRRELEVANT.”

Also not scientifically sound.

The better position is:

DIHEXA POTENTIATES A GROWTH-FACTOR SYSTEM WITH POWERFUL PHYSIOLOGICAL REPAIR FUNCTIONS AND IMPORTANT ONCOLOGIC RELEVANCE. HUMAN EXPOSURE DATA ARE NEEDED TO DEFINE HOW THAT TRANSLATES INTO REAL-WORLD RISK.

That is:

MECHANISM-BASED UNCERTAINTY.

Not fear.

One major reason Dihexa attracted attention is:

BRAIN ACCESS.

Earlier AngIV-related peptides suffered from:

poor BBB penetration 

rapid metabolism 

Chemical modifications produced Dihexa as an:

ORALLY ACTIVE

and:

BLOOD-BRAIN-BARRIER-PERMEABLE

analog in preclinical research. 

That matters because:

A BEAUTIFUL CNS MECHANISM IS CLINICALLY IRRELEVANT IF THE MOLECULE CANNOT REACH THE CNS.

Drug delivery is part of:

MECHANISM.

Technically, Dihexa is often referred to casually as:

A PEPTIDE.

Within the PPI library, that placement is useful because of its:

PEPTIDE-DERIVED BIOLOGY.

But chemically:

PEPTIDOMIMETIC

or:

ANGIV-DERIVED SMALL PEPTIDE ANALOG

is more precise.

This distinction is worth making because it explains why Dihexa can possess:

greater metabolic stability 

greater lipophilicity 

oral activity 

than many native peptides.

Again:

PEPTIDE MEDICINE INCLUDES MORE THAN UNMODIFIED ENDOGENOUS SEQUENCES.

 These two guides fit beautifully together.

P21

Primary concept:

CNTF-DERIVED NEUROTROPHIC SIGNALING

↓

NEUROGENESIS + SYNAPTIC PLASTICITY

DIHEXA

Primary concept:

HGF / c-MET FACILITATION

↓

SPINOGENESIS + SYNAPTOGENESIS

Both may increase:

NETWORK CAPACITY.

But they enter the system through:

DIFFERENT BIOLOGICAL DOORS.

SEMAX

More strongly associated with:

BDNF / TrkB 

ischemia 

neuroprotection 

stress adaptation 

DIHEXA

More strongly associated with:

HGF / c-MET 

dendritic spines 

synaptogenesis 

structural connectivity 

Again

both involve:

PLASTICITY.

But:

PLASTICITY IS AN ENDPOINT CATEGORY, NOT A SINGLE PATHWAY.

 CEREBROLYSIN

A:

MULTICOMPONENT NEUROTROPHIC PREPARATION

with substantial human neurological research.

DIHEXA

A:

DEFINED ANGIOTENSIN-IV–DERIVED PEPTIDOMIMETIC

with much cleaner:

HGF / c-MET

mechanistic identity.

Cerebrolysin:

BROADER BIOLOGY + MORE HUMAN EXPERIENCE.

Dihexa:

MORE TARGETED MECHANISM + EARLIER HUMAN TRANSLATION.

That is the evidence tradeoff.

Alzheimer’s remains Dihexa's most recognizable research domain.

The mechanistic rationale is:

ALZHEIMER'S

↓

SYNAPTIC LOSS

↓

NETWORK FAILURE

↓

MEMORY LOSS

Dihexa

↓

Potential:

HGF / c-MET FACILITATION

↓

SYNAPTOGENESIS

↓

Potential:

NETWORK RECONNECTION

↓

Potential:

COGNITIVE IMPROVEMENT

This is a biologically coherent strategy.

But it may address:

THE CONSEQUENCE OF DISEASE

more than:

THE PRIMARY DRIVER.

That remains an important distinction.

Synapse number often correlates more closely with:

COGNITIVE FUNCTION

than the presence of a single pathological protein alone.

That makes synaptic restoration an important therapeutic concept.

Dihexa research directly addresses:

THAT PROBLEM.

This may ultimately prove useful either:

alone 

or alongside disease-modifying strategies 

because:

STOPPING DAMAGE

and:

REBUILDING CONNECTIONS

are different therapeutic jobs.

Age-related cognitive decline often includes reductions in:

dendritic complexity 

synaptic density 

trophic signaling 

network efficiency 

A synaptogenic intervention therefore has:

MECHANISTIC APPEAL.

But before assuming:

AGE = LOST SYNAPSES,

the Praxis framework asks about:

sleep 

vascular health 

glucose 

medications 

depression 

sensory impairment 

endocrine disease 

Again:

COGNITIVE AGING IS HETEROGENEOUS.

Dihexa may also be conceptually interesting after:

TBI 

stroke 

hypoxic injury 

because recovery often requires:

NEW NETWORK CONNECTIONS.

However, compared with Cerebrolysin or Semax:

the direct disease-specific evidence for Dihexa in these areas is:

LESS DEVELOPED.

That does not make the mechanism irrelevant.

It means:

PATHWAY EVIDENCE ≠ APPLICATION EVIDENCE.

Parkinson’s disease involves:

dopaminergic neuronal loss 

alpha-synuclein pathology 

mitochondrial dysfunction 

altered motor networks 

nonmotor cognitive dysfunction 

Dihexa's proposed relevance comes from:

NEUROTROPHIC + SYNAPTIC CONNECTIVITY BIOLOGY

rather than direct:

DOPAMINE REPLACEMENT.

Again

that could potentially address:

NETWORK FUNCTION

without necessarily correcting:

THE PRIMARY DEGENERATIVE PROCESS.

The 2024 PNB-0408 study broadened interest into Huntington-like neurodegeneration. 

The conceptual question becomes:

CAN HGF-DEPENDENT PLASTICITY OFFSET NETWORK DAMAGE WHEN NEURONS ARE UNDER CONTINUOUS DEGENERATIVE STRESS?

That is important.

But if degeneration continues faster than:

REPAIR,

synaptogenesis alone may eventually be overwhelmed.

Again:

REPAIR RATE VS INJURY RATE.

The APP/PS1 mouse study found lower inflammatory signaling after Dihexa treatment. 

This raises an interesting possibility

perhaps improving:

CELLULAR SURVIVAL + PI3K/AKT SIGNALING

changes the inflammatory environment.

But we should avoid turning this into:

DIHEXA = ANTI-INFLAMMATORY.

Its strongest identity remains:

HGF-MEDIATED SYNAPTIC PLASTICITY.

HGF / c-MET is a classic reminder that:

GROWTH SIGNALING REQUIRES CONTEXT.

In a healing system

growth may be:

NECESSARY.

In an abnormal proliferative system

growth signaling may become:

PATHOLOGIC.

Therefore, a sophisticated Dihexa discussion should not ask:

“IS c-MET GOOD OR BAD?”

It should ask:

“WHAT CELL IS RECEIVING THE SIGNAL, WHY IS c-MET ACTIVE, AND WHAT BIOLOGICAL PROGRAM IS THAT CELL RUNNING?”

That is the Praxis Lens.

Dihexa is an Angiotensin-IV–derived, metabolically stabilized peptidomimetic.

Its chemical identity is N-hexanoic-Tyr-Ile-(6)-aminohexanoic amide.

It was engineered to improve stability, oral activity, lipophilicity, and CNS penetration compared with earlier AngIV-related molecules. 

Dihexa is blood-brain-barrier permeable in preclinical pharmacology. 

Its best-supported mechanistic target is the HGF/c-Met signaling system.

Dihexa binds HGF with high affinity. 

It enhances HGF-dependent c-Met phosphorylation. 

Dihexa has demonstrated hippocampal spinogenesis and synaptogenesis experimentally. 

Blocking HGF/c-Met signaling blocks important Dihexa procognitive effects in animal research. 

Dihexa has improved learning and memory in several preclinical models. 

Its research includes Alzheimer’s models and other neurodegenerative settings. 

PI3K/AKT signaling appears to contribute to effects observed in an APP/PS1 Alzheimer’s mouse model. 

HGF/c-Met is also an important growth and repair pathway outside the nervous system.

Abnormal c-Met signaling occurs in multiple cancers, which makes cellular context relevant when evaluating any long-term HGF-potentiating strategy. 

That oncologic pathway connection is not evidence that Dihexa itself causes cancer.

Direct human therapeutic efficacy and long-term safety remain much less characterized than the preclinical pharmacology.

Dihexa may function as:

A SYNAPTIC RECONSTRUCTION SIGNAL.

The brain suffers:

AGE / DISEASE / INJURY

↓

Dendritic spines are lost.

↓

Synapses disappear.

↓

Neurons may remain alive but become:

FUNCTIONALLY DISCONNECTED.

↓

Cognition declines.

Dihexa

↓

Potential:

HGF SIGNALING BECOMES MORE EFFECTIVE

↓

c-MET

↓

GROWTH / SURVIVAL / PLASTICITY PATHWAYS

↓

Dendritic spines increase.

↓

New functional synapses develop.

↓

Potential:

NETWORK CONNECTIVITY IMPROVES.

Then:

LEARNING / EXPERIENCE / REHABILITATION

provides:

DIRECTION.

In that model:

Dihexa does not primarily:

“MAKE YOU SMARTER.”

It potentially increases:

THE BRAIN'S CAPACITY TO RECONNECT.

That is a fundamentally different concept.

Important questions include:

What exposure is necessary to reproduce preclinical CNS effects in humans? 

What is Dihexa's human pharmacokinetic profile? 

How much reaches the human brain? 

Which brain regions receive the greatest effect? 

How long does HGF potentiation persist? 

What is the optimal degree of c-Met facilitation? 

Does chronic exposure produce receptor adaptation? 

Do new dendritic spines remain stable? 

Are the new synapses functionally appropriate? 

Does cognitive training amplify the effect? 

Can Dihexa improve human Alzheimer’s cognition? 

Does it modify disease progression or primarily compensate for synaptic loss? 

Which neurodegenerative phenotype is most likely to respond? 

How does age alter HGF/c-Met responsiveness? 

What happens in patients with abnormal c-Met signaling? 

What is the relevance of malignancy history or active proliferative disease? 

Does Dihexa alter angiogenic biology meaningfully at therapeutic CNS exposure? 

Which peripheral tissues receive significant exposure? 

What are the long-term consequences of repeated HGF potentiation? 

Can objective imaging or synaptic biomarkers identify responders? 

Could future analogs preserve CNS synaptogenesis while increasing tissue selectivity? 

Again

these questions do not erase:

THE MECHANISTIC SIGNAL.

They identify what must be learned to transform:

A POWERFUL PRECLINICAL MOLECULE

into:

PRECISION CLINICAL NEUROTHERAPEUTICS.