Releasing data on immunization in older volunteers for the first time, Moderna on August 26 said early data of its experimental COVID-19 vaccine showed comparable immune response between older and younger volunteers.
Moderna is one of the leading US contenders in the race to develop a safe, effective vaccine against the novel coronavirus. Its candidate, mRNA-1273, is already in the Phase III stage of human testing.
According to a report by Daily Mail Online, elderly volunteers who were administered the vaccine produced not just high levels of neutralizing antibodies but also managed to produce T cells— type of white blood cells binding and killing the virus.
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Significantly, the report states that the volunteers also produced higher levels of antibodies than those produced by patients who have recovered from COVID-19.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
The analysis looked at a 100-microgram dosage that has been selected for the larger Phase III trial. Moderna said the immune responses in those aged between 56 and 70 years, above 70 and those in the age group of 18 and 55 were similar.
The findings are vital because of the higher risk the virus poses to elderly population.
Moreover, according to the report, with the immune system weakening with age, it becomes hard for vaccines to induce sufficient immune response. This had worried experts regarding any experimental vaccine's effect on elderly population.
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The data was being presented at the US Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices meeting on August 26.
The company has so far enrolled over 13,000 participants in the late-stage study. About 18 percent of the total participants are Black, Latino, American Indian or Alaska Native, groups that are the hardest hit by the pandemic.
According to a news agency Reuters, Dr. Jacqueline Miller, Moderna’s senior vice-president for infectious disease development, told the panel that the company plans to post weekly updates on enrollment of Blacks and Latinos on its website, and hopes to improve on those numbers.
Miller said the company is also tracking enrollment of Asian Americans and Native Americans.
Moderna, which has no drugs on the market, has received nearly $1 billion from the US government under Operation Warp Speed. It has also struck a $1.5 billion supply agreement with the US.
(With inputs from Reuters)