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Moderna releases promising—but early—new coronavirus vaccine data

May 18, 2020, 2:22 PM UTC

Moderna Therapeutics’ first approved treatment may wind up being a coronavirus vaccine.

The Cambridge, Mass., biotech announced positive early-stage data from a Phase I clinical trial of its experimental COVID-19 vaccine candidate, mRNA-1273. The study is being led by the National Institute of Allergy and Infectious Diseases (NIAID), which is housed within the National Institutes of Health (NIH).

All 45 patients given three different dosing levels of mRNA-1273 developed COVID-19 antibodies, according to Moderna. These antibodies are present in the blood of patients who have recovered from a coronavirus infection and may help confer immunity to the disease. Moderna stock soared as much as 30% in early Monday trading on the news.

The biotech specializes in a treatment platform called mRNA therapeutics. In essence, its drug candidates harness messenger RNA, a type of RNA that can transform cells into drugmaking factories by instructing them on what kinds of biological materials, such as antibodies, to create. The company is attempting to devise such treatments for conditions ranging from infectious diseases to cancer.

Patients in Moderna’s trial were given two doses of the vaccine over the course of 43 days at 25-microgram, 100-microgram, and 250-microgram dosing levels via injections in the upper arm. Strikingly, Moderna says that mRNA-1273, at the 100-microgram level, elicited an immune response that created a significantly higher number of coronavirus antibodies than you’d see in a typical patient who has recovered from COVID-19.

The million-dollar question is, Just what does that mean? Only time will tell the strength and staying power of immunity conferred from COVID-19 antibodies, though the hope is they will provide at least some protection.

Moderna has several ongoing studies of mRNA-1273, including a Phase II trial that will include different dosing levels to determine which ones are most appropriate and effective. CEO Stéphane Bancel said in a statement the company also plans to launch Phase III trials in July—and that depending on how the data play out, a vaccine could theoretically reach the market by early 2021.

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