Moderna Inc. (MRNA +4.94%) said Wednesday its experimental coronavirus vaccine induced immune responses in people aged 56 years and older that were comparable to those seen in younger adults in a small study, a promising sign for a vulnerable age group.
Older adults are at higher risk of hospitalization and death from Covid-19 than younger people. While Moderna and other companies are racing to develop vaccines to protect people from the new coronavirus, some experts have been concerned that vaccines won’t offer as much protection in older adults.
The immune system generally weakens with age, which can make it harder for a vaccine to induce a sufficient immune response against disease.
Moderna had released results from its first human study of its vaccine showing that it induced immune responses and was generally safe and well-tolerated in adults ages 18 to 55. The study, led by the National Institutes of Health, was expanded to include people over the age of 55.
In Moderna’s Phase 1 study, volunteers received two doses of the vaccine, four weeks apart. Moderna added to the trial subjects who were 56 years and older to evaluate the vaccine’s safety and effectiveness in the older age groups.
About four weeks after the second shot, the 20 subjects in the trial who were 56 years and older developed what are called neutralizing antibodies—agents of the immune system that fight the virus—in ranges overlapping with those between the ages 18 to 55, according to interim data Moderna presented Wednesday to a committee of outside experts to advise the U.S. Centers for Disease Control and Prevention on vaccine policy.
Moderna, based in Cambridge, Mass., said it plans to submit the results for publication in a peer-reviewed medical journal.
The company has started a large, pivotal trial aimed at assessing whether the immune responses translate into actual protection from Covid-19 disease.
Earlier this month, Moderna said it had agreed to provide 100 million doses to the U.S. government for $1.5 billion. Under the terms of the deal, the U.S. has an option to buy another 400 million doses.