DLX-159 — Safety, Research, Risks & Legal Status

Not medical advice. DLX-159 is discussed here for informational and harm-reduction purposes only. We do not endorse use, and any dosing context is informational, not a protocol.

Also known as	DLX159; Delix Therapeutics pipeline candidate (third-in-class, successor to DLX-001/zalsupindole)
Category	Research Chemical
Developer	Delix Therapeutics, Inc.
Development stage (July 2026)	Preclinical; IND-enabling studies underway; no human trials conducted
Drug class	Non-hallucinogenic neuroplastogen; tryptamine-based small molecule
Key mechanistic features	5-HT2B antagonist; psychoplastogenic effects dependent on 5-HT2A and mTOR signaling; promotes dendritic growth and spinogenesis
First public appearance	ACNP Annual Meeting, December 2024 (presentation No. 320)
Comparator in same program	DLX-001 (zalsupindole) - Phase 1 complete, FDA IND-cleared for Phase 2 as of late 2025
US legal status	Investigational compound in the United States; not FDA-approved for any indication. No IND has been cleared for human use as of mid-2026 - IND-enabling studies are in progress. Not approved as a drug, dietary supplement, or for any human use. Possession and distribution status varies by jurisdiction; no scheduling action specific to DLX-159 has been identified, but it is not legal for human consumption in any regulated context.

What is DLX-159?

DLX-159 is a tryptamine-based small molecule under development by Delix Therapeutics, Inc., classified as a non-hallucinogenic neuroplastogen. It is designed to promote rapid neuronal structural plasticity - including dendritic growth, spinogenesis, and increased synapse density - without producing the hallucinogenic or dissociative perceptual effects associated with classic psychedelics such as psilocybin or LSD. As of mid-2026, it remains entirely preclinical and has not entered human trials.

How it works

Proprietary; not fully disclosed by the developer. Confirmed or inferred activities based on preclinical data: (1) 5-HT2B receptor antagonism, which is associated with reduced cardiovascular liability compared to compounds that agonize this receptor; (2) psychoplastogenic effects that are blocked by ketanserin (a 5-HT2A antagonist) and by rapamycin (an mTOR inhibitor), implicating serotonergic signaling and downstream mTOR pathway activation in its plasticity-promoting mechanism; (3) orally bioavailable and blood-brain barrier penetrant in animal models. Unlike classic psychedelics, DLX-159 does not produce head-twitch response in rodents (a behavioral proxy for hallucinogenic activity) at behaviorally active doses.

Background & history

DLX-159 is the third neuroplastogen candidate from Delix Therapeutics, following DLX-001 (zalsupindole, now in Phase 1b/planned Phase 2) and an intermediate candidate. It first appeared in the public scientific literature in December 2024 via a presentation (No. 320, presenter Kurt Rasmussen, Ph.D.) at the American College of Neuropsychopharmacology (ACNP) Annual Meeting. An abstract appeared in Biological Psychiatry in 2025 (S0006-3223(25)00656-0). As of July 2026, no ClinicalTrials.gov registration exists for DLX-159, and IND-enabling studies are described as underway. The compound's development rationale parallels the broader neuroplastogen hypothesis: that promoting structural synaptic plasticity may underlie the rapid and sustained antidepressant effects observed with psychedelic-adjacent compounds, and that removing the hallucinogenic component may improve tolerability and expand the clinical use case.

What the research says

All available evidence is preclinical (animal and in vitro) as of mid-2026. No human trials have been conducted. Key preclinical findings include: (1) Forced swim test - a single dose produced antidepressant-like behavioral effects within 24 hours, sustained for at least 3 days; (2) Chronic interferon-alpha depression model - reversed depression-like phenotype, suggesting potential relevance to inflammation-associated depression; (3) Structural plasticity assays - significant increases in dendritic growth, spinogenesis, spine density, and spontaneous excitatory postsynaptic currents (sEPSCs) measured 24 hours post-dose. No serious preclinical safety signals reported; no cardiotoxicity observed, consistent with 5-HT2B antagonism. Translation of these findings to humans is unknown. The broader neuroplastogen class is under active investigation across multiple developers; DLX-001 data provide the closest human-adjacent context from the same program.

Reported effects

Preclinical only - antidepressant-like behavioral effects in rodent models within 24 hours of single dose (forced swim test)
Sustained antidepressant-like effects for at least 3 days after single dose in animal models
Reversal of depression-like phenotype in chronic interferon-alpha model (animal)
Increased dendritic growth, spinogenesis, and spine density in neuronal assays within 24 hours
Increased spontaneous excitatory postsynaptic currents (sEPSCs) in preclinical models
No hallucinogenic or dissociative effects observed at behaviorally active doses in animals
No human effect data available - all above reflects animal/in vitro findings only

Dosing & administration (informational)

No human dosing data exists. Preclinical studies used animal-model dose ranges that are not translatable to human protocols without formal clinical pharmacology studies. This field is provided for informational context only and does not constitute a protocol or recommendation. Anyone involved in a legitimate research context should consult the primary literature and a qualified clinician or pharmacologist.

This is general research/context information, not medical advice or a recommended protocol.

Safety & side effects

No human safety data exists - compound has not entered clinical trials as of mid-2026
No cardiotoxicity observed in preclinical studies; 5-HT2B antagonism is considered a protective pharmacological feature relative to 5-HT2B agonism
No psychostimulant effects, head-twitch response, or hallucinogenic behavior observed in rodents at relevant doses
No serious adverse events reported in preclinical studies per available disclosures
Long-term safety, drug-drug interactions, off-target effects in humans, and toxicology in humans are entirely unknown
IND-enabling toxicology studies reportedly in progress; results not yet publicly available
The absence of hallucinogenic effects in animals does not guarantee the same in humans

Drug & supplement interactions

U
n
k
n
o
w
n
.
N
o
h
u
m
a
n
p
h
a
r
m
a
c
o
k
i
n
e
t
i
c
o
r
p
h
a
r
m
a
c
o
d
y
n
a
m
i
c
i
n
t
e
r
a
c
t
i
o
n
d
a
t
a
i
s
a
v
a
i
l
a
b
l
e
.
B
a
s
e
d
o
n
i
t
s
p
r
o
p
o
s
e
d
m
e
c
h
a
n
i
s
m
,
t
h
e
o
r
e
t
i
c
a
l
i
n
t
e
r
a
c
t
i
o
n
s
w
i
t
h
s
e
r
o
t
o
n
e
r
g
i
c
a
g
e
n
t
s
(
S
S
R
I
s
,
S
N
R
I
s
,
M
A
O
I
s
,
o
t
h
e
r
5
-
H
T
2
A
/
2
B
-
a
c
t
i
v
e
c
o
m
p
o
u
n
d
s
)
a
n
d
m
T
O
R
p
a
t
h
w
a
y
m
o
d
u
l
a
t
o
r
s
(
r
a
p
a
m
y
c
i
n
/
s
i
r
o
l
i
m
u
s
,
e
v
e
r
o
l
i
m
u
s
)
s
h
o
u
l
d
b
e
c
o
n
s
i
d
e
r
e
d
r
i
s
k
a
r
e
a
s
,
b
u
t
t
h
i
s
i
s
s
p
e
c
u
l
a
t
i
v
e
e
x
t
r
a
p
o
l
a
t
i
o
n
f
r
o
m
p
r
e
c
l
i
n
i
c
a
l
m
e
c
h
a
n
i
s
t
i
c
d
a
t
a
,
n
o
t
c
l
i
n
i
c
a
l
e
v
i
d
e
n
c
e
.

Who should avoid it

Any use outside a properly authorized clinical trial or research setting
Combination with serotonergic drugs (SSRIs, SNRIs, MAOIs, triptans) - theoretical serotonergic interaction risk, entirely unstudied in humans
Combination with mTOR inhibitors - mechanistic basis for interaction; clinical significance unknown
Sourcing from unregulated vendors - no legitimate supply chain exists; identity and purity cannot be verified
Use by individuals with personal or family history of psychotic disorders - standard precaution for serotonergic psychoplastogens pending human safety data

How it is commonly combined

No stacking data exists. The compound has not been studied in humans in any context, let alone in combination with other agents. No combination use is appropriate outside a supervised clinical trial setting.

Legal & regulatory. Investigational compound in the United States; not FDA-approved for any indication. No IND has been cleared for human use as of mid-2026 - IND-enabling studies are in progress. Not approved as a drug, dietary supplement, or for any human use. Possession and distribution status varies by jurisdiction; no scheduling action specific to DLX-159 has been identified, but it is not legal for human consumption in any regulated context.

Quality & harm reduction

N
o
c
o
m
m
e
r
c
i
a
l
s
u
p
p
l
y
e
x
i
s
t
s
o
r
i
s
a
p
p
r
o
p
r
i
a
t
e
.
D
L
X
-
1
5
9
i
s
a
p
r
o
p
r
i
e
t
a
r
y
i
n
v
e
s
t
i
g
a
t
i
o
n
a
l
c
o
m
p
o
u
n
d
c
o
n
t
r
o
l
l
e
d
b
y
D
e
l
i
x
T
h
e
r
a
p
e
u
t
i
c
s
;
i
t
i
s
n
o
t
a
v
a
i
l
a
b
l
e
t
h
r
o
u
g
h
l
e
g
i
t
i
m
a
t
e
r
e
s
e
a
r
c
h
c
h
e
m
i
c
a
l
v
e
n
d
o
r
s
.
A
n
y
m
a
t
e
r
i
a
l
p
u
r
p
o
r
t
i
n
g
t
o
b
e
D
L
X
-
1
5
9
f
r
o
m
n
o
n
-
p
h
a
r
m
a
c
e
u
t
i
c
a
l
s
o
u
r
c
e
s
c
a
n
n
o
t
b
e
v
e
r
i
f
i
e
d
f
o
r
i
d
e
n
t
i
t
y
,
p
u
r
i
t
y
,
o
r
s
a
f
e
t
y
a
n
d
s
h
o
u
l
d
n
o
t
b
e
u
s
e
d
.

Safer, legal alternative we recommend

NMN It To Win It. For the same cellular-aging/longevity goal, our NMN (a NAD+ precursor) is a legal supplement covering a similar mechanism.

See our recommended pick

Find DLX-159 →

Know your numbers before you research

Order your own bloodwork online — hormone, metabolic and inflammation panels, no doctor visit needed. Know your baselines before and during any protocol. Independent bloodwork is the cheapest insurance there is.

Get tested with Ulta Lab Tests →

Frequently asked questions

Has DLX-159 been tested in humans?

No. As of mid-2026, DLX-159 has not entered human clinical trials. All efficacy and safety data come from animal models and in vitro assays. IND-enabling studies (preclinical toxicology and pharmacology required before a human trial application can be filed) are described as in progress.

What makes DLX-159 different from psilocybin or other psychedelics?

Preclinical data indicate DLX-159 does not produce head-twitch response in rodents (a behavioral correlate of hallucinogenic activity) or other dissociative/perceptual effects at behaviorally active doses. Its developer describes it as a non-hallucinogenic neuroplastogen - a compound that may promote synaptic plasticity through serotonergic and mTOR pathways without the subjective perceptual effects of classic psychedelics. Whether this distinction fully holds in humans is unknown.

What conditions is DLX-159 being developed for?

Based on available preclinical evidence and the developer's stated focus, the primary indication of interest is depression, including potentially inflammation-associated subtypes (suggested by the interferon-alpha model data). No formal indication has been designated by the FDA, and no clinical trial protocol has been registered publicly as of mid-2026.

What is the relationship between DLX-159 and DLX-001?

Both are Delix Therapeutics compounds in the neuroplastogen program. DLX-001 (zalsupindole) is the lead and more advanced candidate - it completed Phase 1 and received FDA IND clearance for a Phase 2 trial in late 2025. DLX-159 is described as a next-generation candidate and successor, currently in preclinical stages. The two compounds share a therapeutic rationale but are distinct chemical entities with separate development timelines.

Can I obtain DLX-159 for research or personal use?

No legitimate supply chain exists for DLX-159. It is a proprietary investigational compound owned by Delix Therapeutics. Any material sold commercially as DLX-159 cannot be authenticated, and use outside a regulated clinical trial context is not appropriate.

What is the recommended dose?

No dosing guidance can be provided. No human dose-finding studies have been conducted. Consult a clinician or pharmacologist and refer to any published clinical trial protocols if and when they become available.

References & further reading

PubMed: DLX-159 neuroplastogen Delix Therapeutics preclinical
PubMed: non-hallucinogenic neuroplastogen antidepressant spinogenesis mTOR 5-HT2A
Biological Psychiatry 2025 abstract S0006-3223(25)00656-0: Preclinical Pharmacology of DLX-159
ClinicalTrials.gov: DLX-001 zalsupindole NCT05983822 Phase 1b (related program; no DLX-159 trial registered)
ACNP Annual Meeting December 2024 Presentation 320 Kurt Rasmussen DLX-159 neuroplastogenicity