Niclosamide

Summary

Niclosamide (CHEMBL1448) is an approved small-molecule antiparasitic agent (ATC P02DA01) targeting KCNT1; indicated across 10 conditions including helminthiasis and severe acute respiratory syndrome.

At a glance

• Status: Approved (max clinical phase 4)
• Modality: Small molecule
• ATC class: P02DA01
• Targets: 1 (KCNT1)
• Indications: 10 conditions
• Clinical trials: 26
• Chemistry: 327.12 Da · C13H8Cl2N2O4

Identifiers

Drug identity and classification

Field	Value
ChEMBL ID	CHEMBL1448
Name	Niclosamide
Type	Small molecule
Max phase	4
FDA approved	no
PubChem CID	4477
ChEBI	CHEBI:7553
ATC	P02DA01
Molecular formula	C13H8Cl2N2O4
Molecular weight	327.12
InChIKey	RJMUSRYZPJIFPJ-UHFFFAOYSA-N

SMILES: C1=CC(=C(C=C1[N+](=O)[O-])Cl)NC(=O)C2=C(C=CC(=C2)Cl)O

IUPAC name: 5-chloro-N-(2-chloro-4-nitrophenyl)-2-hydroxybenzamide

ChEBI definition: A secondary carboxamide resulting from the formal condensation of the carboxy group of 5-chlorosalicylic acid with the amino group of 2-chloro-4-nitroaniline. It is an oral anthelmintic drug approved for use against tapeworm infections.

Pharmacological roles (ChEBI): piscicide, molluscicide, antiparasitic agent, anticoronaviral agent, anthelminthic drug, apoptosis inducer, STAT3 inhibitor.

Also known as: BAY 2353, BAY-2353, Ex a lint, Lintex, Niclocide, Niclosamida, Niclosamide, Niclosamide (anhydrous), Niclosamide anhydrous, anhydrous, Niclosamidum anhydrous, NSC-178296

Parent form; salt/anhydrous children: CHEMBL3794255

Patent coverage: 4,783 distinct patent families (14,322 SureChEMBL compound mentions), from 3 matched compound structure(s). One matched structure accounts for 13,459 (94%) of the total. Mentions count patents naming the compound (not distinct inventions), so promiscuous / reference molecules inflate the mention figure — families are the dedup metric.

Targets

Targets

Primary targets (GtoPdb curated mechanism): the Cancer dependency column is the DepMap CRISPR fitness signal (% of screened cell lines dependent on the target).

Gene	Target	Action	pAffinity	Cancer dependency	UniProt
KCNT1	KNa1.1	Agonist	5.54	1.2%	Q5JUK3

Broader ChEMBL bioactivity targets: 53 (assay-derived). Sample: Tyrosyl-DNA phosphodiesterase 1, Pyruvate kinase PKM, Microtubule-associated protein tau, Nuclear receptor ROR-gamma, Survival motor neuron protein, Prelamin-A/C, RecQ-like DNA helicase BLM, Ferritin light chain, Thrombopoietin, NPC intracellular cholesterol transporter 1.

Bioactivity

ChEMBL activities: 81 potent at pChembl ≥ 5 of 109 total. Top 30 by potency (10 = 0.1 nM, 6 = 1 µM):

Target	pChembl	Type	Value	Unit	Activity ID
P08482	8.74	Potency	1.8	nM	CHEMBL_ACT_4803522
LMNA	7.6	Potency	25.1	nM	CHEMBL_ACT_3631521
ANO1	7.55	IC50	28	nM	CHEMBL_ACT_24761134
TDP1	7.4	Potency	39.8	nM	CHEMBL_ACT_3926614
NPC1	7.4	Potency	39.8	nM	CHEMBL_ACT_4728995
NPC1	7.19	Potency	65.1	nM	CHEMBL_ACT_4745111
RAB9A	7.1	Potency	79.4	nM	CHEMBL_ACT_3849390
RAB9A	7	Potency	100	nM	CHEMBL_ACT_3869505
THPO	7	Potency	100	nM	CHEMBL_ACT_4809375
THPO	7	Potency	100	nM	CHEMBL_ACT_5070386
SMN1	6.9	Potency	125.9	nM	CHEMBL_ACT_3864558
STAT3	6.68	IC50	210	nM	CHEMBL_ACT_23158820
P15917	6.6	Potency	251.2	nM	CHEMBL_ACT_4655628
STAT3	6.6	IC50	250	nM	CHEMBL_ACT_5293841
P0DTD1	6.55	IC50	280	nM	CHEMBL_ACT_25045121
GMNN	6.5	Potency	316.2	nM	CHEMBL_ACT_5061196
PMP22	6.42	Potency	379.3	nM	CHEMBL_ACT_4358676
CYP2C19	6.4	Potency	398.1	nM	CHEMBL_ACT_4014351
CYP2C19	6.4	AC50	398.1	nM	CHEMBL_ACT_6052543
TSHR	6.3	Potency	501.2	nM	CHEMBL_ACT_3920285
MAPK1	6.3	Potency	501.2	nM	CHEMBL_ACT_4545685
TSHR	6.3	Potency	501.2	nM	CHEMBL_ACT_4618553
P15917	6.3	Potency	501.2	nM	CHEMBL_ACT_4633760
TP53	6.3	Potency	501.2	nM	CHEMBL_ACT_4862056
P51450	6.25	Potency	562.3	nM	CHEMBL_ACT_4782320
CYP2C9	6.2	Potency	631	nM	CHEMBL_ACT_5065459
CYP2C9	6.2	AC50	631	nM	CHEMBL_ACT_5989965
HTT	6.1	Potency	794.3	nM	CHEMBL_ACT_3759760
P08659	6.1	Potency	794.3	nM	CHEMBL_ACT_5004925
LMNA	6.05	Potency	891.3	nM	CHEMBL_ACT_3646527

Target pathways

Aggregated over 1 target gene(s): KCNT1.

Dominant GO biological processes

GO term	Targets
protein homotetramerization	1
potassium ion transmembrane transport	1
monoatomic ion transport	1
potassium ion transport	1
monoatomic ion transmembrane transport	1

Indications & clinical

Indications

10 indications (1 at ChEMBL trial phase 4). Phase below is the highest clinical-trial phase recorded for this drug against each disease — not the molecule’s overall approval status (that is in the Summary).

Indication	Trial phase	MONDO	EFO
helminthiasis	4	MONDO:0004664	EFO:1001342
severe acute respiratory syndrome	3	MONDO:0005091	MONDO:0100096
diabetic kidney disease	3	MONDO:0005016	EFO:0000401
metastatic prostate carcinoma	2	MONDO:0004956	EFO:0000196
colorectal neoplasm	2	MONDO:0005335	MONDO:0005575
rheumatoid arthritis	1	MONDO:0008383	EFO:0000685
colonic neoplasm	1	MONDO:0005401	MONDO:0021063
acute myeloid leukemia	1	MONDO:0018874	EFO:0000222

2 further indication records had no mapped disease name (EFO/MeSH-only) or were duplicates, and are omitted.

Clinical trials

Total trials: 26.

Phase distribution

Phase	Trials
PHASE2	10
PHASE1	6
PHASE3	3
PHASE2/PHASE3	2
PHASE1/PHASE2	2
Not specified	2
PHASE4	1

Top trials by phase / activity

NCT	Phase	Status	Title
NCT05087381	PHASE4	COMPLETED	Randomized-controlled Trial of the Effectiveness of COVID-19 Early Treatment in Community
NCT04317430	PHASE3	COMPLETED	Niclosamide Role in Diabetic Nephropathy
NCT04372082	PHASE3	WITHDRAWN	Hydroxychloroquine or Diltiazem-Niclosamide for the Treatment of COVID-19
NCT04558021	PHASE3	UNKNOWN	A Study To Evaluate The Efficacy And Safety Of a Novel Niclosamide Suspension Formulation For COVID-19
NCT04603924	PHASE2/PHASE3	COMPLETED	Study of Niclosamide in Moderate and Severe Hospitalized Coronavirus-19 (COVID-19) Patients
NCT04870333	PHASE2/PHASE3	COMPLETED	PROphylaxis for paTiEnts at Risk of COVID-19 infecTion -V
NCT02807805	PHASE2	ACTIVE_NOT_RECRUITING	Abiraterone Acetate, Niclosamide, and Prednisone in Treating Patients With Hormone-Resistant Prostate Cancer
NCT02519582	PHASE2	UNKNOWN	Drug Trial to Investigate the Safety and Efficacy of Niclosamide Tablets in Patients With Metastases of a Colorectal Cancer Progressing After Therapy
NCT03160001	PHASE1/PHASE2	COMPLETED	Niclosamide With Etanercept in Rheumatoid Arthritis
NCT03521232	PHASE1/PHASE2	TERMINATED	A Study of Niclosamide Enemas in Subjects With Active Ulcerative Proctitis or Ulcerative Proctosigmoiditis
NCT04296851	PHASE2	UNKNOWN	Niclosamide for Familial Adenomatous Polyposis
NCT04399356	PHASE2	COMPLETED	Niclosamide for Mild to Moderate COVID-19
NCT04436458	PHASE2	WITHDRAWN	Niclosamide In Moderate COVID-19
NCT04542434	PHASE2	WITHDRAWN	Niclosamide in COVID-19
NCT04750759	PHASE2	TERMINATED	Safety and Preliminary Efficacy of the Combination of Niclosamide and Camostat
NCT04753619	PHASE2	UNKNOWN	Effectiveness of Niclosamide as Add-on Therapy to the Standard of Care Measures in COVID-19 Management
NCT04858425	PHASE2	TERMINATED	Safety and Efficacy of Niclosamide in Patients With COVID-19 With Gastrointestinal Infection
NCT04932915	PHASE2	TERMINATED	Safety and Efficacy of Intranasal Administration of Niclosamide (UNI91103) in Adults With Asymptomatic or Mild COVID-19
NCT05188170	PHASE1	RECRUITING	Niclosamide in Pediatric Patients With Relapsed and Refractory AML
NCT02532114	PHASE1	COMPLETED	Niclosamide and Enzalutamide in Treating Patients With Castration-Resistant, Metastatic Prostate Cancer
NCT02687009	PHASE1	TERMINATED	A Study of Niclosamide in Patients With Resectable Colon Cancer
NCT03123978	PHASE1	COMPLETED	Enzalutamide and Niclosamide in Treating Patients With Recurrent or Metastatic Castration-Resistant Prostate Cancer
NCT04644705	PHASE1	COMPLETED	Safety and Pharmacokinetics of a Novel Niclosamide Solution in Combination With Camostat
NCT04705415	PHASE1	COMPLETED	A Single and Multiple Ascending Dose Study of Niclosamide in Healthy Volunteers
NCT00138359	Not specified	TERMINATED	Mass Treatment T Solium Community Study
NCT01296958	Not specified	COMPLETED	Targeted Screening for Taenia Solium Tapeworms

Clinical evidence (CIViC)

No CIViC predictive evidence (expected for non-precision-medicine drugs).

Pharmacology

Pharmacogenomics

No CPIC/DPWG dosing guideline or drug-level clinical/variant annotations in PharmGKB for this molecule.

Related molecules

Related molecules

Molecules sharing ≥1 of this drug’s curated primary targets, merged from two biobtree sources and ranked by shared-target count, then clinical phase: ChEMBL clinical-stage candidates (development phase ≥2) and PubChem drug-class bioactivity (approved / known drugs acting on the target). Deduplicated by drug name; the drug’s own salt forms are excluded. Note: for a drug with few primary targets a shared-target match can reflect off-target / promiscuous binding rather than the same therapeutic mechanism — the phase ordering surfaces bona-fide therapeutics first.

3 molecules share ≥1 primary target. Top 3 by shared-target count:

Molecule	Source	Status	Shared targets
QUINIDINE	ChEMBL + PubChem	Phase 4 (approved)	KCNT1
BEPRIDIL	ChEMBL	Phase 4 (approved)	KCNT1
Loxapine	PubChem	Approved	KCNT1