Major U.S. indices closed higher on Wednesday, with the Dow Jones Industrial Average rising 0.22% to 53,463.05.

MRK, MRNA's cancer vaccine breakthrough could revive the mRNA trade, putting biotech and genomics ETFs back in focus.

Major U.S. indices closed higher on Wednesday, with the Dow Jones Industrial Average rising 0.22% to 53,463.05.

Healthcare stocks saw mixed after-hours moves, with Moderna and Merck cooling after explosive gains on positive cancer trial results.