A drug used to treat non-small cell lung cancer that has spread to other parts of the body and is anaplastic lymphoma kinase (ALK) positive. It is also being studied in the treatment of other types of cancer. Alectinib blocks certain proteins made by the ALK gene. Blocking these proteins may stop the growth and spread of cancer cells. Alectinib is a type of tyrosine kinase inhibitor. Also called Alecensa.