According to the complaint, on December 8, 2023, Blue announced that the Food and Drug Administration (FDA) approved its drug Lyfgenia (lovotibeglogene autotemcel), also known as lovo-cel for the treatment of sickle cell disease in patients ages 12 and older who have a history of vaso-occlusive events (VOEs). However, the Lyfgenia approval came with a black box warning for haematological malignancies after two patients developed AML during the clinical trials. Analysts noted that they did not expect the black box warning or the absence of a priority review voucher. Following this news, Blue’s stock price fell by $1.95 per share, or approximately 40% to close at $2.86 per share.