Moderna’s vaccine is given in two doses 28 days apart and can be extended to 42 days. It has shown to be effective around 14 days after one receives the first dose. Image: AP

After developing one of three vaccines being widely-used to protect the global population against COVID-19 disease, US company Moderna Therapeutics has now announced a “next-generation” vaccine in its kitty that has begun early-stage trials. The company said it has dosed the first patients with its new candidate, known as mRNA-1283. The mRNA vaccine candidate can potentially be stored in refrigerators, according to statement from Moderna, instead of the ultracold or freezer temperatures required by other widely-available vaccines. This could open up opportunities for developing countries to secure doses of the mRNA vaccine, provided it clears human trials without a hitch.

The mRNA-1283 vaccine is designed to code for part of the SARS-CoV-2 virus spike protein – a highly-conserved sequence in all human coronavirus es (HCoVs) that is important for the virus to attach and multiple in cells. Like the bulk of COVID-19 vaccines developed so far, mRNA-1283 is also designed to seek out and neutralize the SARS-CoV-2 virus by targetting the spike protein. However, being an mRNA vaccine, it will do so by passing on instructions to our cells to make a harmless piece of the spike protein.

In the Phase 1 study, Moderna plans to evaluate three different doses in health volunteers to test the safety and immune response from mRNA-1283. The trial will evaluate a higher, single dose of the vaccine as well as a lower, double dose given 28 days apart. The data from the trial will be compared with the dosage for the company’s earlier successful vaccine, mRNA-1273. The phase 1 study of Moderna’s mRNA-1273 vaccine showed that participants had high levels of neutralizing antibodies against COVID-19 119 days after their first dose was administered.

Moderna said in the statement that mRNA-1283 will eventually also be tested as a booster dose for people who have already been vaccinated, or having antibodies from an earlier COVID-19 infection.

The current Moderna vaccine for COVID-19 is a two-dose vaccine, which needs to be stored at minus 20 degrees Fahrenheit (normal freezer temperatures). The Pfizer-BioNTech COVID-19 vaccine requires storage at minus 94 degrees Fahrenheit (ultra-cold temperatures). Almost 3 billion of the 7.8 billion global population live in regions where temperature-controlled storage is insufficient for an immunization campaign to bring COVID-19 under control, according to a report by the Associated Press.