Pharmacy chain Walgreens Boots Alliance is in early talks to buy out AmerisourceBergen, one of the big three drug distributors, the Wall Street Journal reports. Walgreens already owns a 26% stake in the company.

Why it matters: The combined company would be gigantic, with about $276 billion in annual revenue. Only Walmart would be bigger among U.S. companies. The deal would also house pharmacies and drug distribution under one roof — yet another instance of the health care industry's merger frenzy as companies rush to build scale and fend off any Amazon entrance.