Berkeley Lovelace Jr.
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Each participant was assigned to receive a 25 microgram, 100 mcg or 250 mcg dose, with 15 people in each dose group. Study participants received two doses of the potential vaccine via intramuscular injection in the upper arm approximately 28 days apart. Data on a second dose was not available for the 250 mcg group, the company said.
At day 43, or two weeks following the second dose, levels of binding antibodies in the 25 mcg group were at the levels generally seen in blood samples from people who recovered from the disease, the company said. Antibodies in the 100 mcg had antibodies that “significantly exceeded levels” in recovered patients.
The vaccine also produced neutralizing antibodies against Covid-19 in at least eight participants, the company said. Four participants were assigned to receive a 25 microgram dose, while the other four received 100 mcg. Levels of neutralizing antibodies were at or above levels in blood samples, the company said. Data on neutralizing antibodies for the other participants were not yet available, Moderna said.
“These interim Phase 1 data, while early, demonstrate that vaccination with mRNA-1273 elicits an immune response of the magnitude caused by natural infection starting with a dose as low as 25 µg,” Tal Zaks, the chief medical officer at Moderna, said in s statement.
“When combined with the success in preventing viral replication in the lungs of a pre-clinical challenge model at a dose that elicited similar levels of neutralizing antibodies, these data substantiate our belief that mRNA-1273 has the potential to prevent COVID-19 disease and advance our ability to select a dose for pivotal trials,” Zaks added.
There are formally approved treatments for Covid-19, which has killed at least 315,225 and sickened 4.7 million people worldwide since emerging from the Chinese city of Wuhan more than 4 months ago, according to data compiled by Johns Hopkins University.
Moderna has been fast-tracking work with the National Institutes of Health, an agency within the Department of Health and Human Services, to develop a vaccine.
The company said the vaccine was generally safe and well tolerated.
The potential vaccine by Moderna contains genetic material called messenger RNA, or mRNA, that was produced in a lab. The mRNA is a genetic code that tells cells what to build — in this case, an antigen that may induce an immune response for the virus.
The phase 1 trial took place at the Kaiser Permanente Washington Health Research Institute in Seattle, Washington. It tested the vaccine on 45 males and non-pregnant females between the ages of 18 and 55.