ST. LOUIS / DEERFIELD, IL, 2018-Feb-21 — /EPR Retail News/ — Express Scripts Holding Company (NASDAQ: ESRX) and Walgreens Boots Alliance, Inc. (NASDAQ: WBA) today February 20, 2018) announced they are expanding their group purchasing efforts to include the procurement of specialty brand drugs.  Given the savings potential associated with biosimilars in the coming years, the…