Check out the companies making headlines in midday trading.

Merck — Shares surged more than 9% after it announced its new antiviral pill cut the risk of death or hospitalization by 50% for Covid patients. The pharmaceutical company plans to file for emergency use authorization.

Moderna, Regeneron — Companies with other Covid-19 drugs fell after Merck’s oral pill showed positive data in a clinical trial. Moderna’s stock fell nearly 13%, while shares of Regeneron dropped more than 5%.

United Airlines, Delta Air Lines, American Airlines, Southwest Airlines — Airline stocks rallied as Merck’s oral Covid drug showed promising results. United Airlines rose nearly 6%, Delta Air Lines gained more than 5% and American Airlines rallied roughly 4%. Southwest Airlines jumped more than 4% as well following an upgrade on the stock by JPMorgan.

Penn National Gaming, Hilton Worldwide, Norwegian Cruise Line — Travel and entertainment stocks jumped following the positive results from Merck’s Covid pill. Penn National Gaming rallied more than 6%, Live Nation Entertainment added about 5%, Hilton Worldwide gained more than 4% and Norwegian Cruise Line rose nearly 4.8%.

Lordstown Motors — Lordstown Motors saw its stock sink more than 15% after it announced an agreement to sell its Ohio assembly plant to iPhone maker Foxconn for $230 million. Shares of Lordstown Motors had rallied by as much as 21% by Thursday as reports indicated the deal was in the works.

Zoom Video Communications — Zoom and Five9 terminated what would have been a $14.7 billion deal. Five9 shareholders rejected the proposed acquisition by Zoom. Zoom shares gained 2.2% and Five9 shares rose 3.2%.

Walt Disney — Shares of the media giant popped 3% on news that Disney and Scarlett Johansson settled a lawsuit involving the “Black Widow” movie. Johansson had sued Disney over the release of the movie on the Disney+ streaming service at the same time it was debuting in theaters.

Exxon Mobil – The oil giant advanced more than 2% after the company updated Wall Street on its expected third-quarter results. In a filing with the Securities and Exchange Commission, Exxon said that higher oil and gas prices could lift earnings by as much as $1.5 billion. Analysts at Bank of America said the company is on track for its highest earnings per share since the third quarter of 2014.

International Flavors & Fragrances – Shares of International Flavors popped more than 6% after the company announced its chief executive Andreas Fibig plans to retire. The company said Fibig will remain at the helm of the company until a successor is found.

— CNBC’s Jesse Pound and Maggie Fitzgerald contributed reporting