FDA Grants Breakthrough Therapy Designation to Moderna for Investigational RSV Vaccine

Officials with the FDA have granted Breakthrough Therapy Designation to Moderna’s investigational respiratory syncytial virus (RSV) vaccine candidate, mRNA-1345, in adults aged 60 years or older.

mRNA-1345 consists of a single mRNA sequence encoding for a stabilized prefusion F glycoprotein and uses the same lipid nanoparticles as the Moderna COVID-19 vaccines. The F glycoprotein is on the surface of the virus and is necessary for infection by helping the virus enter host cells. The prefusion conformation is a significant target of potent neutralizing antibodies and is highly conserved across both RSV-A and RSV-B subtypes.

The Breakthrough Therapy Designation is based on positive topline data from the ConquerRSV phase 3 pivotal efficacy trial and is intended to expedite the development and review of drugs intended to treat a serious condition, such as RSV. The designation is also given when preliminary clinical evidence indicates that the drug or vaccine may demonstrate substantial improvement over available therapy.

“The FDA’s Breakthrough Designation for mRNA-1345 further emphasizes the significant health impact of RSV in older adults and the high unmet need,” said Stephane Bancel, CEO of Moderna, in a press release. “With this designation, we look forward to productive conversations with the FDA in the hopes of bringing our RSV vaccine candidate for older adults to the market safely and quickly.”

The mRNA-1345 vaccine candidate was previously granted Fast Track designation by the FDA in August 2021. Moderna plans to submit a license application for regulatory approval in the first half of 2023.

ConquerRSV is a randomized, double-blind, placebo-controlled study evaluating the efficacy of mRNA-1345 against RSV-caused lower respiratory tract disease (RSV-LRTD) as defined by 2 or more symptoms. The study met its primary efficacy endpoints, including vaccine efficacy of 83.7% against RSV-LRTD as defined by 2 or more symptoms and efficacy of 82.4% in RSV-LRTD as defined by 3 or more symptoms.

The vaccine was generally well-tolerated and no clinically significant safety signals were identified. To date, most solicited adverse events (AEs) were mild or moderate and the most commonly reported solicited AEs in the mRNA-1345 group were injection site pain, fatigue, headache, myalgia, and arthralgia. The overall rate of severe solicited systemic AEs was 4% for mRNA-1345 and 2.8% for placebo. The study is ongoing, and an updated analysis of safety and tolerability will be provided at the time of regulatory submission.

RSV is a highly contagious seasonal respiratory virus and a leading cause of lower respiratory tract infections and pneumonia, with a particularly large burden of disease in infants and older adults. RSV causes an estimated 5.2 million cases and nearly a half-million hospitalizations in adults 60 years of age or older reported across high-income countries in 2019.

Complications in adults include respiratory distress, pneumonia, bronchitis, hospitalization, and death. In addition to acute infection, RSV can also exacerbate underlying medical conditions such as asthma and chronic obstructive pulmonary disease, and can result in acute myocardial infarction, stroke, and long-term decline of respiratory functions.

REFERENCE

Moderna Granted FDA Breakthrough Therapy Designation for mRNA-1345, an Investigational Respiratory Syncytial Virus (RSV) Vaccine Candidate. News release. Moderna; January 30, 2023. Accessed February 1, 2023. https://investors.modernatx.com/news/news-details/2023/Moderna-Granted-FDA-Breakthrough-Therapy-Designation-for-mRNA-1345-An-Investigational-Respiratory-Syncytial-Virus-RSV-Vaccine-Candidate/default.aspx