What happened

Shares of Moderna (NASDAQ:MRNA) climbed 33.7% in May, according to data provided by S&P Global Market Intelligence, after the company reported encouraging data from its investigational coronavirus vaccine's phase 1 trial.

A researcher injects a globe with vaccine.

Image source: Getty Images.

Across all participants in two dosage groups, Moderna said, levels of binding antibodies were at or above levels seen in people who have recovered from the virus. Information on neutralizing antibodies (those that block infection) were only available for eight people. In those participants, neutralizing antibodies were also at or above levels found in recovered coronavirus patients.

Later in the month, Moderna announced the dosing of the first participants in its phase 2 trial. The company aims to start a phase 3 trial in July.

So what

Moderna was the first to start human trials and among the first to release results. Since there isn't an approved treatment or cure for the coronavirus, the world is eager for a vaccine. As a result, all eyes are on Moderna, which seems closest to the finish line. That said, the initial data released involves a limited number of participants in a young patient group (ages 18 to 55), and anything can happen in this ongoing trial as well as in later-stage trials.

Moderna also faces competition. The biotech is among 10 companies and research institutions that have brought a vaccine candidate into human trials. That said, there is likely room for more than one vaccine to serve worldwide demand.

The trials also are significant because the coronavirus vaccine, if approved, would be Moderna's first marketed product. The vaccine harnesses the power of messenger RNA to instruct the body to produce therapeutic proteins. Moderna uses this technology throughout its other programs, so positive data here may indicate the method could work in other diseases.

Now what

Investors should watch for more data from the ongoing phase 1 trial as well as data from the phase 2 trial, which will involve 600 participants in two age groups. Safety and immune response in older adults, who are most affected by the coronavirus, will be key, as will the production of neutralizing antibodies.

Like peers working on a coronavirus vaccine, Moderna may see its stock price soar on positive data, while a setback for the project would likely be a setback for the shares as well.

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