Here's a look at the companies making headlines in midday trading: FedEx — The delivery giant's stock price plunged more than 13% after reporting a sharp decline in quarterly earnings. The company also lowered its full-year revenue forecast. Chief Executive Raj Subramaniam said industrial demand was weaker than expected, while FedEx customers continued to shift to cheaper, slower delivery options, squeezing profits. Nike — The apparel stock rose 5.8% after announcing a CEO change. Nike veteran Elliott Hill will replace John Donahoe in October. The company's stock price fell about 25% in the year before the announcement. Constellation Energy — Shares of Constellation Energy soared more than 17% after the company announced plans to restart its Three Mile Island nuclear power plant and sell power to Microsoft to meet its data center energy needs. Accordingly, Microsoft will purchase power from the plant through a 20-year agreement. Novo Nordisk — Shares of Novo Nordisk fell 5.5% after disappointing trial results for the drugmaker's experimental obesity drug monlunabant. Analysts at Deutsche Bank called the results “impressive” compared with Eli Lilly and Company's orforglipron. Shares of Corbus Pharmaceuticals, which is developing a drug similar to Novo Nordisk, plunged about 60%. Rivals Eli Lilly and Viking Therapeutics gained 1% and 4.3%, respectively. Vistra — The Texas-based electric utility's shares rose more than 12% after the company announced it would acquire all 15% of its subsidiary Vistra Vision that it does not already own for nearly $3.25 billion in cash. The transaction is expected to close on December 31. Lennar – Shares of Lennar fell 4% despite the homebuilder beating fiscal third-quarter earnings and revenue estimates. Lennar reported earnings of $4.26 per share on revenue of $9.42 billion. Meanwhile, the consensus is for revenue of $9.17 billion and profit of $3.63, according to data from the London Stock Exchange (LSEG). ASML — The semiconductor stock fell 3.4% after Morgan Stanley downgraded the stock to equal weight from overweight. Morgan Stanley said risk-reward ratios have been “balanced.” Centessa Pharmaceuticals — The biotech stock rose more than 4% after Morgan Stanley upgraded the stock to overweight from equal weight. The bank said it believes the drugmaker's narcolepsy treatment has the potential to become best-in-class. Valero Energy — The energy stock fell nearly 3% after Piper Sandler downgraded its rating to neutral from overweight, citing “less room for outperformance.” Chewy — Shares of Chewy fell 4.8% after the pet products retailer announced $500 million in Class A shares underwritten by Buddy Chester. In addition, Chewy plans to purchase $300 million from Buddy Chester and will cancel and retire the repurchased shares following the transaction. —CNBC’s Alex Harring, Brian Evans, Samantha Subin, Yun Li, Lisa Kailai Han, Jesse Pound and Michelle Fox contributed reporting.