What happened
Shares of Moderna (MRNA 4.65%) rose 4.9% on Monday, after the biotechnology company said it began a study of an experimental COVID-19 vaccine with less restrictive storage requirements.
So what
Moderna dosed the first participants in its phase 1 trial of mRNA-1283, the biotech's refrigerator-stable COVID-19 vaccine candidate. Should it prove both safe and effective, the new vaccine would be easier to transfer, store, and administer, according to CEO Stephane Bancel. That could make it particularly compelling for distribution in markets with less advanced healthcare infrastructure.

Investors bid up Moderna's stock price on Monday. Image source: Getty Images.
The phase 1 study is designed to evaluate the safety and immunogenicity of mRNA-1283. Moderna will test several different dose levels of the drug. The results will be compared to those of mRNA-1273, Moderna's authorized COVID-19 vaccine.
Moderna also plans to conduct future studies to evaluate mRNA-1283 as a potential booster dose for previously vaccinated people.
Now what
Moderna's mRNA-1273 has demonstrated remarkable efficacy against COVID-19 in clinical trials. The vaccine has also been shown to be safe and generally well tolerated. However, when stored for periods of more than 30 days, the drug must be stored frozen between -25 and -15 degrees Celsius (-13 to 5 degrees Fahrenheit). These storage requirements can prove challenging for many developing countries.
A refrigerator-stable COVID-19 vaccine would be easier to distribute in areas where freezers are harder to come by. Such a drug would help to expand Moderna's addressable market, as well as its long-term profit potential.