| abstract |
The present invention relates to the crystalline forms of 2-allyl-1-[6-(I-hydroxy-1 methylethyl)pyridin-2-yl]-6-{[4-(4-methylpiperazin-1-yl)phenyl]amino}-1,2-dihydro-3H-pyrazolo[3,4-d]pyrimidin-3-one or a salt thereof, which are useful in the field of treatment of various cancers as a kinase inhibitor, especially as a Weel kinase inhibitor. |