Commenting on The Wall Street Journal report saying Walgreens (WBA) has approached AmerisourceBergen (ABC) in a takeover attempt and the companies remain early in their discussions, Wells Fargo analyst Peter Costa tells investors he believes the acquisition makes sense given the already existing long-term partnership and limited ability to merge laterally. Further, the analyst believes a potential combination could help lower costs and wring out synergies in the U.S. drug distribution channel, and better position Walgreens in the face of increasing competitive threat from a possible Amazon (AMZN) entry. However, a merger might risk alienating AmerisourceBergen's retail pharmacy customers that compete with Walgreens' pharmacies, he contends.