<a href="http://www.cnn.com/specials/politics/joe-biden-news" target="_blank">President Joe Biden</a> is set to announce on Tuesday that drugmaker Merck will <a href="http://www.cnn.com/world/live-news/coronavirus-pandemic-vaccine-updates-03-02-21/index.html" target="_blank">help manufacture a vaccine</a> developed by Johnson & Johnson, administration officials familiar with the matter said, increasing production capacity as the third authorized shot begins going into arms.
The arrangement between two