Moderna gave its mRNA-based seasonal flu vaccine to the first set of volunteers in a clinical trial, the pharmaceutical company announced today. The start of the trial marks the next stage of the company’s work on this type of vaccine technology after the overwhelming success of its COVID-19 vaccine, which was built using the same strategy.
Before the COVID-19 pandemic, mRNA vaccines were still largely experimental, even as they were heralded as the future of vaccine development. People who get an mRNA vaccine are injected with tiny snippets of genetic material from the target virus. Their cells use that genetic information to build bits of the virus, which the body’s immune system learns to fight against.
The high efficacy of the mRNA COVID-19 vaccines made by Moderna and Pfizer / BioNTech was a major endorsement for this type of vaccine. Now, pharmaceutical companies plan to use this technology to fight other types of infectious diseases, including flu. The flu shots available each year in the United States are usually between 40 and 60 percent effective. The most common shots are made by growing the influenza virus in cells or chicken eggs, and then killing the virus so it’s no longer dangerous. It takes a long time to grow the virus, so companies have to start making the shots around six months ahead of time, based on predictions around which strain of the flu will be circulating that year.
Pharmaceutical companies hope that mRNA-based flu vaccines can be more effective than the traditional shots. Because they’d be faster to make, production wouldn’t have to start so far in advance, and they could theoretically be more closely matched with the type of flu spreading each season.
Moderna is the second group to start testing its mRNA flu shot in human trials — Sanofi and Translate Bio kicked off a trial this summer. Pfizer and BioNTech have been interested in mRNA flu shots for a few years, and they’re pushing forward with those plans as well.
Moderna says it hopes to eventually create combination vaccines that could protect people against flu, COVID-19, and other respiratory infections with one shot. “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,” Stéphane Bancel, chief executive officer of Moderna, said in a press release.
If flu shots using this technology prove to be safe and effective, it could also make us more prepared for a potential pandemic flu in the future. It’s a fairly simple process to design a shot that could target a new influenza virus. “[mRNA] gives us a very strong platform for a rapid response,” Rosemary Rochford, an immunologist at the University of Colorado, told The Verge last fall.