Adapalene

Adapalene
Clinical data
Trade names	Differin, others
AHFS/Drugs.com	Monograph
MedlinePlus	a604001
License data	US DailyMed: Adapalene;
Pregnancy; category	AU: D;
Routes of; administration	Topical
Drug class	Retinoids
ATC code	D10AD03 (WHO) ;
Physiological data
Receptors	Retinoic acid receptor (RAR)
Metabolism	Known to accumulate in the liver and GI-tract. In human, mouse, rat, rabbit, and dog cultured hepatocytes, metabolism appears to affect the methoxybenzene moiety but remains incompletely characterized. The major products of metabolism are glucuronides. Approximately 25% of the drug is metabolized; the rest is excreted as parent drug
Legal status
Legal status	AU: S4 (Prescription only) / S3; BR: Class C2 (Retinoids); CA: ℞-only; UK: POM (Prescription only); US: OTC / Rx-only;
Pharmacokinetic data
Bioavailability	Very low
Metabolism	Known to accumulate in the liver and GI-tract. In human, mouse, rat, rabbit, and dog cultured hepatocytes, metabolism appears to affect the methoxybenzene moiety but remains incompletely characterized. The major products of metabolism are glucuronides. Approximately 25% of the drug is metabolized; the rest is excreted as parent drug
Metabolites	Glucuronides
Elimination half-life	between 7 and 51 hours
Excretion	Bile duct
Identifiers
	IUPAC name 6-[3-(1-adamantyl)-4-methoxyphenyl]naphthalene-2-carboxylic acid;
CAS Number	106685-40-9 ;
PubChem CID	60164;
IUPHAR/BPS	5429;
DrugBank	DB00210 ;
ChemSpider	54244 ;
UNII	1L4806J2QF;
KEGG	D01112 ;
ChEBI	CHEBI:31174 ;
ChEMBL	ChEMBL1265 ;
CompTox Dashboard (EPA)	DTXSID5046481 ;
ECHA InfoCard	100.149.379
Chemical and physical data
Formula	C28H28O3
Molar mass	412.529 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	300 °C (572 °F)
Boiling point	606.3 °C (1,123.3 °F)
	SMILES COC1=C(C=C(C=C1)C2=CC3=C(C=C2)C=C(C=C3)C(=O)O)C45CC6CC(C4)CC(C6)C5;
	InChI InChI=InChI=1S/C28H28O3/c1-31-26-7-6-23(21-2-3-22-12-24(27(29)30)5-4-20(22)11-21)13-25(26)28-14-17-8-18(15-28)10-19(9-17)16-28/h2-7,11-13,17-19H,8-10,14-16H2,1H3,(H,29,30) ; Key:LZCDAPDĜCYOEH-UHFFFAOYSA-N ;
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Adapalene, sold under the brand name Differin among others, is a third-generation topical retinoid primarily used in the treatment of mild-moderate acne, and is also used off-label to treat keratosis pilaris as well as other skin conditions. Studies have found adapalene is as effective as other retinoids, while causing less irritation. It also has several advantages over other retinoids. The adapalene molecule is more stable compared to tretinoin and tazarotene, which leads to less concern for photodegradation. It is also chemically more stable compared to the other two retinoids, allowing it to be used in combination with benzoyl peroxide. Due to its effects on keratinocyte proliferation and differentiation, adapalene is superior to tretinoin for the treatment of comedonal acne and is often used as a first-line agent. The Swiss company Galderma developed adapalene.