Vaccine maker Novavax announced Wednesday that its combination vaccine that targets COVID-19 and the flu provided a strong immune response based on early data conducted.

According to Yale Medicine, the Novavax vaccine differs from Pfizer and Moderna’s mRNA shots in that it's a protein adjuvant, meaning an ingredient used to improve immune response. mRNA vaccines work by instructing cells to make a nondangerous piece of a “spike protein,” found on the surface of the coronavirus.

“What we demonstrated in this study is we were able to get the immune responses really comparable to what the individual vaccines did prior to combination,” Chief Medical Officer Filip Dubovsky said, as reported by CNBC.

Trial participants were all previously vaccinated against COVID-19. Novavax will exhibit its findings at the World Vaccine Congress in Washington, D.C., on Wednesday.

“We’re encouraged by these data and the potential path forward for a combination Covid-19-influenza vaccine as well as stand-alone vaccines for influenza and Covid-19,” Novavax's president of R&D Gregory Glenn said, as reported by Forbes.

The Food and Drug Administration's head of vaccine safety Dr. Peter Marks said earlier this month that in order for shots to be available this fall, a decision regarding future doses must be made by this June. "Many variants are coming, and Omicron was the first one that was able to evade, in a skillful way, the immune protection that we're giving," Pfizer CEO Albert Bourla told CBS in March, asserting that a fourth dose is "necessary."