- Moderna's plans to reinvent the seasonal flu shot began in earnest this week, as the first participants in a small clinical trial received an experimental influenza vaccine the biotech company is developing.
- The experimental candidate uses the same messenger RNA technology that powered Moderna's vaccine for COVID-19 and is designed to target four influenza strains that widely circulate each year.
- In a Wednesday statement, Moderna said it plans to enroll 180 adults in the Phase 1/2 trial, which will test a range of vaccine doses. While the drugmaker has previously tested mRNA vaccines against influenza in early studies, this newly launched trial is the first to evaluate one for protection against seasonal flu strains.
Moderna's work to develop mRNA-based vaccines wasn't always well received by investors in the biotech, who, in years prior to the COVID-19 pandemic, had viewed the field as a less lucrative application of the company's technology.
The dramatic success of Moderna's coronavirus vaccine, as well as another similar shot from Pfizer and BioNTech, has evaporated many of those doubts and vaulted Moderna's market value above that of Gilead, Vertex, Regeneron and Biogen.
Having proved mRNA's might in preventing COVID-19, Moderna aims to do the same in seasonal flu, for which available vaccines are typically between 40% to 60% effective. One reason for their relatively modest efficacy is how they are usually designed. Each year, laboratories around the world send influenza virus samples to centers that help the World Health Organization predict which strains should be included in the annual shot.
Those predictions are made six to nine months ahead of time to allow for manufacturing, sometimes resulting in a mismatch between the available vaccine and the strains that are circulating in a given year.
In theory, an mRNA vaccine could be adapted more quickly, as has been shown with Moderna and Pfizer's fast work in designing booster shots tailored to specific coronavirus variants that have emerged since the pandemic began.
"There's a world in which we don't have to use the guess the WHO makes in February on seasonal flu strain," Stéphane Bancel, Moderna's CEO, told BioPharma Dive in an interview last year. "We could do that much later with a strain that's much closer to what's happening in the U.S."
The Phase 1/2 trial that recently got underway is testing a vaccine candidate, dubbed mRNA-1010, designed to protect against seasonal influenza A H1N1, H3N2 and influenza B Yamagata and Victoria. Moderna said it expects to test multiple candidates targeted to different flu strains in clinical trials.
The company previously tested two mRNA vaccines against the less common strains H10N8 and H7N9. Results from Phase 1 studies, published in the journal Vaccine in May 2019, showed the candidates spurred immune responses and were generally safe, although further testing is needed to determine whether they're protective against infection or disease.
Moderna's broader aim is to eventually develop combination vaccines that can protect against several respiratory diseases simultaneously, a goal it argues is well addressed by using mRNA.
"Our vision is to develop an mRNA combination vaccine so that people can get one shot each fall for high efficacy protection against the most problematic respiratory viruses," Bancel said in the company's Wednesday statement.
Moderna said it plans to study potential combination vaccines against influenza, SARS-CoV-2, respiratory syncytial virus, or RSV, and human metapneumovirus.
Pfizer is working on an mRNA vaccine against seasonal flu as well, and hopes to begin testing a candidate shot in 2022.