The federal agency’s decision was based from data of the company’s phase 3 ConquerRSV trial.
Image credit: FDA
The FDA approved Moderna’s mRNA 1345 (mRESVIA) vaccine, and it is indicated for seniors 60 years of age and older in prevention of lower respiratory tract disease caused by RSV infection.
The approval was based from the results of the phase 3 ConquerRSV trial, which demonstrated an 83.7% efficacy against infection.
“The FDA approval of our second product, mRESVIA, builds on the strength and versatility of our mRNA platform,” Moderna CEO Stéphane Bancel, said in a statement. “mRESVIA protects older adults from the severe outcomes of RSV infection, and it is the only RSV vaccine available in a pre-filled syringe designed to maximize ease of administration, saving vaccinators’ time and reducing the risk of administrative errors. This approval is also the first time an mRNA vaccine has been approved for a disease other than COVID-19. With mRESVIA, we continue to deliver for patients by addressing global public health threats related to infectious diseases.” 1
What the Data Demonstrated
The phase 3 ConquerRSV trial was a randomized, double-blind, placebo-controlled study of approximately 37,000 adults who are 60 years or older across 22 countries.The investigators based their primary efficacy endpoints around 2 definitions of RSV-LRTD defined as either two or more symptoms, or three or more symptoms of disease.2
The interim analysis was based on 64 cases of RSV-LRTD with 2 or more symptoms, of which 55 occurred in the placebo group and 9 occurred in the mRNA-1345 group, and 20 cases of RSV-LRTD with three or more symptoms, of which 17 cases were observed in the placebo group compared with three cases observed in the mRNA-1345 group. The other primary efficacy endpoint against RSV-LRTD defined by three or more symptoms was also met, with a VE of 82.4% (96.36% CI: 34.8%, 95.3%; p=0.0078). The trial is ongoing, and additional efficacy analyses are planned as cases accrue, including for severe RSV.3
A subsequent analysis from the ConquerRSV study with a longer median follow-up duration of 8.6 months (versus 3.7 months in the primary analysis), with a range of 15 days to 530 days, and including subjects from the Northern and Southern Hemispheres was recently presented at the RSVVW’24 conference. In this supplemental analysis, mRNA-1345 maintained durable efficacy, with sustained VE of 63.3% (95.88% CI: 48.7%, 73.7%) against RSV-LRTD including two or more symptoms. VE was 74.6% (95% CI: 50.7%, 86.9%) against RSV-LRTD with ≥2 symptoms, including shortness of breath and 63.0% (95% CI: 37.3%, 78.2%) against RSV-LRTD including three of more symptoms.4
In terms of safety, a review of available safety data was also conducted by the DSMB. The mRNA-1345 vaccine was well tolerated with no safety concerns identified, according to the investigators. Safety and tolerability will continue to be followed in this ongoing study. To date most solicited adverse reactions were mild or moderate and the most commonly reported solicited adverse reactions in the mRNA-1345 group were injection site pain, fatigue, headache, myalgia, and arthralgia. The overall rate of severe (Grade 3 or greater) solicited systemic adverse reactions was 4.0% for mRNA-1345 and 2.8% for placebo. The overall rate of Grade 3 or greater solicited local adverse reactions was 3.2% for mRNA-1345 and 1.7% for placebo.2
Table. Here are some specific details about the vaccine.
Table created by ChatGPT.
The RSV Vaccine’s Makeup
mRNA-1345 consists of a single mRNA sequence encoding for a stabilized prefusion F glycoprotein. The vaccine uses the same lipid nanoparticles (LNPs) as in the Moderna COVID-19 vaccines. The F glycoprotein is on the surface of the virus and is required for infection by helping the virus to enter host cells. It exists in two states, prefusion and postfusion. The prefusion conformation is a significant target of potent neutralizing antibodies and is highly conserved across both RSV-A and RSV-B subtypes.
Next Steps
The company said it plans to manufacture the vaccine and have it available to the public for eligible populations in the US by the 2024/2025 respiratory virus season.1
