Nemtabrutinib

Nemtabrutinib (MK-1026, formerly ARQ 531) is a small molecule drug is a Bruton's tyrosine kinase (BTK) inhibitor; unlike first generation BTK inhibitors it does not bind covalently, and inhibits the ATP binding site of BTK, and was designed to inhibit Src family kinases and kinases related to ERK signalling, along with BTK.^[1]

Nemtabrutinib

Clinical data
Other names	MK-1026; ARQ 531
Legal status
Legal status	Investigational
Identifiers
IUPAC name (2-chloro-4-phenoxyphenyl)-(4-{[(3R,6S)-6-(hydroxymethyl)oxan-3-yl]amino}-7H-pyrrolo[2,3-d]pyrimidin-5-yl)methanone
CAS Number	2095393-15-8
PubChem CID	129045720
UNII	JTZ51LIXN4
Chemical and physical data
Formula	C25H23ClN4O4
Molar mass	478.93 g·mol−1
3D model (JSmol)	Interactive image
SMILES O=C(c1ccc(Oc2ccccc2)cc1Cl)c1c[nH]c2ncnc(N[C@@H]3CC[C@@H](CO)OC3)c12
InChI InChI=1S/C25H23ClN4O4/c26-21-10-17(34-16-4-2-1-3-5-16)8-9-19(21)23(32)20-11-27-24-22(20)25(29-14-28-24)30-15-6-7-18(12-31)33-13-15/h1-5,8-11,14-15,18,31H,6-7,12-13H2,(H2,27,28,29,30)/t15-,18+/m1/s1 Key:JSFCZQSJQXFJDS-QAPCUYQASA-N

Merck paid $2.7 billion to acquire the company ArQule and the drug, which at the time had just completed a Phase I clinical trial as a treatment for B-cell cancers.^[2] As of December 2024 Merck had started Phase III trials in chronic lymphocytic leukaemia and other blood cancers, and had finished a Phase I trial for kidney disease.^[3][4]