Moderna says RSV vaccine is effective in older adults

Moderna’s vaccine against respiratory syncytial virus (RSV) was 83 percent effective at preventing lower respiratory tract disease in adults aged 60 and older in a large clinical trial, the company announced on Tuesday.

Based on the results, Moderna said it intends to submit the vaccine for Food and Drug Administration (FDA) approval in the first half of 2023. The announcement puts Moderna into a crowded marketplace of RSV vaccines for older adults, including giants GlaxoSmithKline and Pfizer.

Both companies have applied for FDA approval of their respective RSV vaccines and expect decisions in May. 

Moderna said the vaccine was 83.7 percent effective at preventing two key symptoms, like fever, cough or difficulty breathing. The vaccine was 82.4 percent effective at preventing severe RSV cases with three or more symptoms present, the company said.

There is no vaccine for RSV in either adults or children. In healthy adults and older children, RSV typically causes mild, cold-like symptoms that go away with moderate rest and self-care. But it can result in severe illness in infants and older adults.

RSV infections kill between 6,000 and 10,000 adults over age 65 every year and results in 60,000 to 120,000 hospitalizations, according to the Centers for Disease Control and Prevention. RSV kills between 100 and 300 children in the U.S. each year.

Like the flu, RSV season usually occurs during colder weather, though this year it hit unusually hard and early, contributing to a wave of respiratory infections that led to overwhelmed hospitals nationwide.

Moderna’s RSV vaccine uses the same messenger RNA technology as the company’s COVID-19 shots. The company said its vaccine is also being tested in an ongoing early stage trial in pediatric populations.

“Today’s results represent an important step forward in preventing lower respiratory disease due to RSV in adults 60 years of age and older. These data are encouraging, and represent the second demonstration of positive phase 3 trial results from our mRNA infectious disease vaccine platform after, Spikevax, our COVID-19 vaccine,” Moderna’s CEO Stéphane Bancel said in a statement.

The company said it will publish the full data set in a peer reviewed journal and present it at an upcoming infectious disease conference.

Moderna said its Phase 3 trial enrolled about 37,000 people ages 60 and older in 22 countries including the U.S. About half were given a single dose of the RSV vaccine and the other half received a placebo. 

The vaccine was well tolerated with no safety concerns. Most adverse reactions were mild or moderate and the most commonly reported were injection site pain, fatigue, headache, muscle ache and joint stiffness.