Etidronic Acid

Summary

Etidronic Acid (CHEMBL871) is an approved small-molecule bone density conservation agent (ATC M05BA01); indicated across 2 conditions including bone disorder and autosomal recessive inherited pseudoxanthoma elasticum.

At a glance

• Status: Approved (max clinical phase 4)
• Modality: Small molecule
• ATC class: M05BA01
• Indications: 2 conditions
• Clinical trials: 7
• Chemistry: 206.03 Da · C2H8O7P2

Identifiers

Drug identity and classification

Field	Value
ChEMBL ID	CHEMBL871
Name	Etidronic Acid
Type	Small molecule
Max phase	4
FDA approved	no
PubChem CID	3305
ChEBI	CHEBI:4907
ATC	M05BA01
Molecular formula	C2H8O7P2
Molecular weight	206.03
InChIKey	DBVJJBKOTRCVKF-UHFFFAOYSA-N

SMILES: CC(O)(P(=O)(O)O)P(=O)(O)O

IUPAC name: (1-hydroxy-1-phosphonoethyl)phosphonic acid

ChEBI definition: A 1,1-bis(phosphonic acid) that is (ethane-1,1-diyl)bis(phosphonic acid) having a hydroxy substituent at the 1-position. It inhibits the formation, growth, and dissolution of hydroxyapatite crystals by chemisorption to calcium phosphate surfaces.

Pharmacological roles (ChEBI): bone density conservation agent, chelator, antineoplastic agent.

Also known as: Acide etidronique, Acido etidronico, Etidronate, Etidronic acid, M05BA01, NSC-227995, SID29215269, SID93576729, etidronic acid, ehdp, ETIDRONIC ACID, ACIDE_ETIDRONIQUE

Parent form; salt/anhydrous children: CHEMBL1201042, CHEMBL1874205

Patent coverage: 24,175 distinct patent families (73,508 SureChEMBL compound mentions), from 1 matched compound structure(s). Mentions count patents naming the compound (not distinct inventions), so promiscuous / reference molecules inflate the mention figure — families are the dedup metric.

Targets

Targets

Broader ChEMBL bioactivity targets: 1 (assay-derived). Sample: Prelamin-A/C.

Bioactivity

ChEMBL activities: 1 potent at pChembl ≥ 5 of 1 total. Top 100 by potency (10 = 0.1 nM, 6 = 1 µM):

Target	pChembl	Type	Value	Unit	Activity ID
LMNA	5.9	Potency	1259	nM	CHEMBL_ACT_3666974

Target pathways

No target-pathway data for this drug (no mapped target genes).

Indications & clinical

Indications

1 approved indication. FDA phase 4, plus an anticancer drug’s labelled cancer uses (which ChEMBL often logs at phase 3).

Indication	Phase	MONDO	EFO
bone disorder	4	MONDO:0005381	EFO:0004260

1 disease in clinical trials (phase 1–3, investigational — not approved indications). Highest ChEMBL trial phase per disease; a non-cancer approved use is occasionally logged at phase 3 here.

Disease (in trials)	Phase	MONDO	EFO
autosomal recessive inherited pseudoxanthoma elasticum	3	MONDO:0009925	MONDO:0009925

Clinical trials

Total trials: 7.

Phase distribution

Phase	Trials
Not specified	3
PHASE2	2
PHASE4	1
PHASE3	1

Top trials by phase / activity

NCT	Phase	Status	Title
NCT00376662	PHASE4	COMPLETED	HRT Versus Etidronate for Osteoporosis and Fractures in Asthmatics Receiving Glucocorticoids.
NCT05832580	PHASE3	RECRUITING	The Prevention of Systemic Ectopic Mineralization in Pseudoxanthoma Elasticum
NCT05662111	PHASE2	RECRUITING	Treatment of Ectopic Calcification in Fahr’s Disease or Syndrome
NCT01585402	PHASE2	COMPLETED	Etidronate for Arterial Calcifications Due to Deficiency in CD73 (ACDC)
NCT07116252	Not specified	ACTIVE_NOT_RECRUITING	Effect of Different Irrigation Protocols on Postoperative Endodontic Pain and Inflammation
NCT01077817	Not specified	COMPLETED	Observational Study of Incidence Rates of Esophageal Cancer in Women Taking Medications for the Prevention or Treatment of Osteoporosis (MK-0217A-352)
NCT05778227	Not specified	COMPLETED	Comparing Different Single and Combination Chelating Agents on Sealer Penetration and Dentin Erosion.

Clinical evidence (CIViC)

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

Pharmacology

Pharmacogenomics

No CPIC/DPWG dosing guideline, but PharmGKB curates 1 clinical and 2 variant annotation(s) for this drug (gene-keyed; see PharmGKB).

Related molecules

Related molecules

No competitor molecules sharing a primary target (ChEMBL phase ≥2 or PubChem drug-class).