Moderna Inc says early data of its experimental coronavirus vaccine shows it induced immune responses in older adults that were similar to younger participants.
The drug developer is one of the leading US contenders in the race to develop a safe and effective jab against COVID-19 and its candidate, mRNA-1273, is already in the Phase III stage of human testing.
However, this marks the first time the company has released data on how well its immunization works in older patients.
Elderly volunteers not only produced high levels of neutralizing antibodies but also T-cells, which are a type of white blood cell that binds to and kills viruses, Moderna said on Wednesday.
What’s more, the levels of antibodies were higher than those among patients who have recovered from coronavirus infection.
Moderna’s vaccine, mRNA-1273, tricks the body into producing some of the viral proteins, which the immune system then recognizes and builds a defensive response against.
Despite currently being in Phase III testing, these results are from Phase I, and include new analysis from 20 additional people and details on how the vaccine performs in older people.
Older adults are among the groups at highest-risk of developing severe cases of COVID-19, which could result in hospitalization and death.
Because the immune system weakens with age, it is often hard for vaccines to induce a sufficient immune response, which has made some experts worry that any experimental vaccine for the coronavirus might not be as a effective in the elderly.
Researchers tested the virus in two groups of 10, the first between ages 56 and 70 and a second in elderly adults aged 71 and older.
All volunteers received two 100 microgram doses of the inoculation, which were administered 28 days apart.
In addition to high levels of antibodies, the vaccine did not appear to result in any severe side effects, according to the Massachusetts-based company said.
Some participants reported chills, fatigue, headaches and pain at the site of injection, but most symptoms resolved within two days.
The data will be presented at the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices meeting on Wednesday.
The results have not been published yet, but the company says it plans to submit them for publication in a peer-reviewed medical journal.
Moderna, which has no drugs in the market, has received nearly $1 billion from the US government under a plan called Operation Warp Speed to speed up vaccine development for COVID-19, which has killed more than 178,000 Americans.
Earlier this month, Moderna also struck a $1.5 billion supply agreement with the US to produce 100 million doses. The deal allows the government to buy another 400 million doses if the jab proves successful.
Shares of the drug developer rose more than seven percent to $71.35 after the data was released.
According to the World Health Organization, there are more than 170 vaccines in development around the world with at least 31 in clinical trials.
Last month, Moderna started a phase III large-scale trial testing the safety and efficacy of its immunization in 30,000 people.
So far, officials say more than 13,000 participants have joined the late-stage study with enrollment anticipated to be completed by September and expect preliminary results as early as October.