Alectinib, also known by the brand name Alecensa, is a potent protein kinase inhibitor of ALK and RET tyrosine kinases. This drug is prescribed in the treatment of non-small cell lung cancer (NSCLC).

The use of alectinib causes acanthocytosis by also inhibiting proteins in the membrane of the erythrocyte. This creates an abnormal membrane structure resulting in an acquired red blood cell membrane disorder and acanthocytosis. Because of the abnormal shape, these erythrocytes are increasingly trapped and removed from the circulation in the spleen, which can lead to anemia in these patients.