Merck announced it will halt development of its COVID-19 vaccines, noting a lack of adequate evidence they are effective. The pharma company will instead focus on developing two COVID-19 treatments. (STAT)

Moderna said Monday its COVID-19 vaccine is effective against new variants discovered in the U.K. and South Africa. The company added that it is working on a “booster shot” of the vaccine aimed at the South Africa variant. (The New York Times)

AstraZeneca said its leukemia drug Calquence proved just as effective as Imbruvica in a Phase III study. According to the company, the study showed Calquence was safer than Imbruvica, a blockbuster developed by Johnson & Johnson and AbbVie, and caused fewer cases of atrial fibrillation. (Endpoints News)

President Biden announced travel restrictions in the wake of the emergence of new COVID-19 variants. The restrictions include bans on non-U.S. citizens traveling from South Africa, Brazil and the U.K. (POLITICO)

Pfizer has enrolled more than 2,200 participants in its COVID-19 vaccine trial for children aged 12 to 15. The results will determine whether the vaccine is safe for administration among children in that age range. (CNBC Weekly)