In the following video, Motley Fool health care bureau chief Brenton Flynn discusses an upcoming FDA decision on this Sunday, Feb. 10, on whether to approve Celgene's (CELG) drug pomalidomide, which is used in the treatment of blood cancer multiple myeloma. While there is little doubt that the drug will be approved, Brenton highlights the bigger question at stake here: Considering the competition in this space -- including one of Celgene's own drugs, which may cannibalize sales -- just how big will this drug become?