A potential vaccine (mRNA-1273) for the COVID-19 novel coronavirus being produced by Moderna, Inc., a clinical stage biotechnology firm, has shown promising results from the Phase 1 study led by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH).
A total of eight volunteers ages 18 to 55 across three dose levels (25 mg, 100 mg and 250 mg) were administered two doses of the vaccine, two weeks apart, with blood drawn after one dose (day 29) and two weeks after the second dose (day 43).
The vaccine appeared to have been successful, at least at this initial stage. “Consistent with the binding antibody data, mRNA-1273 vaccination elicited neutralizing antibodies in all eight of these participants, as measured by plaque reduction neutralization (PRNT) assays against live SARS-CoV-2. The levels of neutralizing antibodies at day 43 were at or above levels generally seen in convalescent sera.”
It was also “generally safe and well tolerated, with a safety profile consistent with that seen in prior Moderna infectious disease vaccine clinical studies,” the company said in a release. “The sole incidence of a grade 3 adverse event in the 25 µg and 100 µg dose cohorts was a single participant at 100 µg who experienced grade 3 erythema (redness) around the injection site. To date, the most notable adverse events were seen at the 250 µg dose level, comprising three participants with grade 3 systemic symptoms, only following the second dose. All adverse events have been transient and self-resolving. No grade 4 adverse events or serious adverse events have been reported.”
Based on the interim Phase 1 data, the company is set to move ahead shortly to Phase 2, with an amendment to study two dose levels, 50 mg and 100 mg, “with the aim of selecting a dose for pivotal studies.”
Moderna said it expects Phase 3 trials to begin in July, subject to finalization of the clinical trial protocol.
“With today’s positive interim Phase 1 data and the positive data in the mouse challenge model, the Moderna team continues to focus on moving as fast as safely possible to start our pivotal Phase 3 study in July and, if successful, file a BLA,” said Stéphane Bancel, Chief Executive Officer at Moderna.
“We are investing to scale up manufacturing so we can maximize the number of doses we can produce to help protect as many people as we can from SARS-CoV-2.”