Palbociclib

Palbociclib
Clinical data
Pronunciation	/ˌpælboʊˈsaɪklɪb/; PAL-boh-SYE-klib
Trade names	Ibrance, others
Other names	PD-0332991
AHFS/Drugs.com	Monograph
MedlinePlus	a615013
License data	US DailyMed: Palbociclib;
Pregnancy; category	AU: D;
Routes of; administration	By mouth
ATC code	L01EF01 (WHO) ;
Legal status
Legal status	AU: S4 (Prescription only); CA: ℞-only; UK: POM (Prescription only); US: ℞-only; EU: Rx-only;
Pharmacokinetic data
Bioavailability	46%
Protein binding	85%
Metabolism	Liver (CYP3A, SULT2A1, glucuronidation)
Elimination half-life	29 (±5) hours
Excretion	74% feces, 18% urine
Identifiers
	IUPAC name 6-Acetyl-8-cyclopentyl-5-methyl-2-{[5-(1-piperazinyl)-2-pyridinyl]amino}pyrido[2,3-d]pyrimidin-7(8H)-one;
CAS Number	571190-30-2;
PubChem CID	5330286;
DrugBank	DB09073;
ChemSpider	4487437;
UNII	G9ZF61LE7G;
KEGG	D10372;
ChEBI	CHEBI:85993;
ChEMBL	ChEMBL189963;
PDB ligand	LQQ (PDBe, RCSB PDB);
CompTox Dashboard (EPA)	DTXSID40972590 ;
ECHA InfoCard	100.238.221
Chemical and physical data
Formula	C24H29N7O2
Molar mass	447.543 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES O=C2N(c1nc(ncc1/C(=C2/C(=O)C)C)Nc3ncc(cc3)N4CCNCC4)C5CCCC5;
	InChI InChI=1S/C24H29N7O2/c1-15-19-14-27-24(28-20-8-7-18(13-26-20)30-11-9-25-10-12-30)29-22(19)31(17-5-3-4-6-17)23(33)21(15)16(2)32/h7-8,13-14,17,25H,3-6,9-12H2,1-2H3,(H,26,27,28,29); Key:AHJRHEGDXFFMBM-UHFFFAOYSA-N;

Palbociclib, sold under the brand name Ibrance among others, is an anti-cancer medication used for the treatment of HR-positive and HER2-negative breast cancer. It was developed by Pfizer. It is a selective inhibitor of the cyclin-dependent kinases CDK4 and CDK6. Palbociclib was the first CDK4/6 inhibitor to be approved as a cancer therapy.

The most common side effects include neutropenia (low blood levels of neutrophils, a type of white blood cell that fights infection), infections, leucopenia (low white blood cell counts), tiredness, nausea (feeling sick), stomatitis (inflammation of the lining of the mouth), anemia (low red blood cell counts), diarrhea, alopecia (hair loss), and thrombocytopenia (low blood platelet counts). The most common severe side effects include neutropenia, leucopenia, infections, anemia, tiredness, and increased blood levels of liver enzymes (aspartate and alanine transaminases).