in july 2012, bristol-myers squibb announced it would acquire amylin pharmaceuticals for $5.3 billion. as part of the acquisition, astrazeneca made a $3.4 billion cash payment to make amylin a wholly owned subsidiary within the existing bms/az joint venture in diabetes. in april 2013, bristol-myers squibb announced it would close amylin's san diego operations by the end of 2014 and merge the amylin manufacturing facility in west chester, ohio and all field-based sales personnel into bristol-myers squibb operations.