Health-care companies were lower but not by as much as the broader market as Covid-19 remained in the spotlight.

A vaccine being developed by the University of Oxford and AstraZeneca PLC showed a promising immune response and low levels of adverse reactions in the elderly and older adults, according to an interim analysis that the drugmaker said was encouraging.

Meanwhile, according to officials at the European Medicine Agency, the body would be willing to approve a Covid-19 vaccine even if it showed a so-called efficacy rate below 50%, as long as the shot were safe enough to justify the benefits. That's lower than the threshold the U.S. Food and Drug Administration is likely to apply in assessing vaccine candidates for the U.S. population.

Bayer said Monday it would pay as much as $4 billion for U.S. biotech firm Asklepios BioPharmaceutical Inc. to strengthen the German company's drugmaking arm, as Bayer continues to reel from its acquisition of crops giant Monsanto.

Write to Amy Pessetto at amy.pessetto@dowjones.com

(END) Dow Jones Newswires

10-26-20 1702ET