Why the Leading U.S. Healthcare Stock is Down Over 6% Ahead of Earnings

McKesson Corporation (MCK) saw its share price tumble 6.38% intraday on May 6, closing at $749.92 and dragging its market capitalization down to about $91.8 billion (roughly KRW 130 trillion). With investor sentiment already weakened by disappointing results and guidance shocks at other major drug distributors, profit‐taking and position reductions ahead of its Q4 FY2026 earnings report—due after the close on May 7—eroded approximately $5.5 billion (around KRW 8 trillion) in market value in a single day.

On April 24, McKesson arranged a new $5 billion revolving credit facility led by Bank of America, extending its liquidity runway through 2031, and simultaneously terminated its existing $1 billion and $4 billion credit lines early. The company is also speeding up its business realignment and capital‐structure optimization by bringing in Apollo as a strategic minority investor in its planned spin-off Medical & Surgical Solutions unit.

Headquartered in Irving, Texas, McKesson is the largest pharmaceutical wholesaler and healthcare services provider in the U.S., supplying roughly one-third of all medicines consumed in North America. In fiscal 2025, the company generated about $359 billion in revenue (approximately KRW 500 trillion). Drawing on its role as the U.S. federal government’s central vaccine distribution partner during the COVID-19 pandemic—delivering hundreds of millions of vaccine doses and related supplies—McKesson remains a cornerstone of America’s healthcare supply chain infrastructure.