Stocks making the biggest movements after hours: GM, Snap, Merck

Discover the companies that make the headlines after the bell:

Merck & Co's shares lost up to 9% in prolonged trading on Monday, before erasing those losses, after the drug company announced that its drug Keytruda had not met expectations at the time. of phase 3 of the drug trial. Keytruda, a breast cancer drug, has not shown results that meet the desired requirements compared to chemotherapy patients.

Snap's shares rose slightly after the company announced the appointment of a new chief financial officer, who would immediately take over from interim chief financial officer, Lara Sweet. The social media company has proposed to Derek Andersen, Snap's current Vice President of Finance, to permanently fill the position of Chief Financial Officer. Lara Sweet will assume the role of Chief of Staff.

General Motors shares lost value after news of the news that the company would terminate its "Maven" car-sharing service in eight of the 17 cities of North America where it is currently proposed. Maven, launched in 2016, will end the service in the coming months in cities like Chicago and Boston. GM has not revealed the complete list of cities where the service will be deleted. The cities in which the service will continue to operate include Los Angeles, Washington DC, Detroit and Toronto.

Shares of Mercury Systems have fallen more than 5% after the aerospace and defense company announced that it would issue 5 million common shares as part of a public call for savings. The company intends to allocate the net proceeds of the offer to the refinancing or repayment of debt and to future acquisitions, as well as to other expenses of the company. 39; company.