DexCom (DXCM) shares tumbled 5.06% in after-hours trading on Wednesday, despite reporting better-than-expected second-quarter results and announcing a CEO succession plan. The medical device company, known for its continuous glucose monitoring systems, saw its stock price decline sharply following the release of its quarterly earnings report.

DexCom reported adjusted earnings per share of $0.48, surpassing the analysts' estimate of $0.44. Revenue for the quarter reached $1.157 billion, exceeding the expected $1.124 billion. The company also raised its full-year 2025 revenue guidance to between $4.60 billion and $4.625 billion, up from its previous forecast.

Despite these positive results, investors seemed to focus on other factors. The company announced that President and COO Jake Leach will become CEO and join the board effective January 1, 2026, with current CEO Kevin Sayer remaining as executive chairman during the transition. This leadership change, coupled with possible concerns about future growth or market expectations, may have contributed to the stock's after-hours decline. The market's reaction suggests that investors might be reassessing the company's valuation or have concerns about its long-term strategy that outweigh the strong quarterly performance.