Respiratory Syncytial Virus (RSV) Vaccines 2024
Developing safe and effective respiratory syncytial virus (RSV) vaccines continues to be a priority of the World Health Organization (WHO). Since the 1960s, vaccine researchers have studied RSV vaccine candidates. As of July 2024, the U.S. Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), the UK's Medicines and Healthcare products Regulatory Agency (MHRA), and the European Commission (EC) recommend certain adults and pregnant women receive a single dose of an RSV vaccine based on specific conditions. On June 26, 2024, the CDC's ACIP committee recommended most older people receive an RSV vaccination. RSV vaccines have been approved in Canada, Europe, Japan, the United States, and the United Kingdom.
RSV Vaccines Approved in the U.S.
AREXVY™ RSV vaccine is approved for adults. AREXVY became available in U.S. pharmacies on August 17, 2023.
ABRYSVO™ RSVpreF, an RSV bivalent vaccine from Pfizer Inc., received approval from the U.S. FDA and European Commission for older adults and pregnant women in 2023.
mRESVIA® mRNA-1345 is a vaccine against RSV developed by ModernaTX, Inc. It is approved for use in the U.S. and recommended in Europe.
RSV Vaccination Rate USA
According to the CDC's RSVVaxView, the overall RSV vaccination rate among pregnant women was about 17.8% as of 2024. As of May 22, 2024, an estimated 24.4% (95% Confidence Interval: 23.7%-25.2%) of adults 60 years and older report receiving an RSV vaccine. Across the U.S., receipt of an RSV vaccine was lowest in Mississippi, 14.2%, and highest in Colorado, 32.2%.
RSV Vaccine Candidates 2024
Various pharmaceutical companies are conducting phase 3 clinical trials on RSV vaccine candidates.
CSPC Pharmaceutical Group Limited mRNA RSV vaccine candidate SYS6016 is conducting clinical trials in China.
Icosavax / AstraZeneca's IVX-121, an RSV and hMPV vaccine candidate, incorporates a stabilized prefusion F antigen licensed from NIAID/NIH (DS-CAV1). VLP technology further enhances the response's magnitude, quality, and durability to the prefusion RSV F. There are currently no treatments or preventative therapies for hMPV and no combination vaccines for RSV. In a Phase 1 trial, IVX-A12 induced robust immune responses against RSV and hMPV at Day 28 in older adults across dosage levels and with and without adjuvant. The ongoing Phase 2 clinical trial of IVX-A12 results include IVX-A12 induced geometric mean titers (GMTs) in RSV-A neutralizing antibody titers (nAbs) of approximately 12,200 IU/mL compared to approximately 2,000 IU/mL for placebo at Day 28. IVX-A12 induced GMTs in RSV-B nAbs of approximately 5,500 IU/mL compared to approximately 1,300 IU/mL for placebo at Day 28; IVX-A12 induced GMTs in hMPV-A nAbs of approximately 1,600 assay units/mL compared to approximately 400 assay units/mL for placebo at Day 28. IVX-A12 induced GMTs in hMPV-B nAbs of approximately 15,300 assay units/mL compared to approximately 6,700 assay units/mL for placebo at Day 28. No standardized international units exist in the field for hMPV.
Clover Biopharmaceuticals, Ltd. SCB-1019 is a bivalent RSV-A/RSV-B vaccine candidate based on the prefusion-stabilized F (PreF) protein leveraging the validated Trimer-Tag platform and proprietary stabilizing PreF mutations. On June 18, 2024, Clover announced positive preliminary immunogenicity and safety data in the older adult & elderly cohort from its Phase clinical trial evaluating SCB-1019.
Codagenix Inc. CodaVax™-RSV is an intranasal, live-attenuated vaccine candidate for preventing RSV infection that received U.S. FDA Fast Track designation and has launched two phase 1 studies. A pediatric Phase 1 study evaluating CodaVax has an age de-escalation, dose-escalation design specifically assessing safety and immunogenicity in the 6-month-to-5-year-old population.
Meissa Vaccines MV-012-968 is an investigational, live attenuated vaccine protecting against RSV. Meissa's intranasal live attenuated MV-012-968 vaccine candidate induces systemic solid mucosal IgA antibody response in RSV-naïve children. As of August 8, 2023, 100% of RSV-naïve infants and toddlers responded to two doses of 107 PFU of MV-012-968. Safety data show that MV-012-968 is well-tolerated and highly attenuated, with no related serious adverse events, no Grade 2 or 3 fever reported, and low levels of transient vaccine virus shedding detected at the highest doses.
ResVax is a vaccine candidate from Novavax composed of recombinant RSV F nanoparticles adsorbed to aluminum phosphate. The F protein is essential to RSV infectivity and is the target of palivizumab.
DS-Cav1 was developed by VRC, NIAID, and is composed of the RSV fusion glycoprotein ectodomain assembled as a trimer stabilized in its prefusion native conformation with a foldon trimerization domain at the C-terminus and four internal mutations designated DS-Cav1 (4.1DHFR_RSVAF).
Ad26.RSV preF vaccine is a protein-based RSV vaccine candidate tested on adults produced by Pfizer, Inc.
EDP-938, Enanta's lead N-protein inhibitor, is being developed to treat RSV infection and was granted Fast Track Designation by the U.S. FDA.
Icosavax Inc. IVX-A12 is a bivalent (RSV/hMPV) formulation, incorporating single and multiple hMPV dosage levels in older adults 60 and above. The FDA granted Fast Track designation for IVX-A12 on February 21, 2023.
Artificial Cell Technologies, Inc. developed a fully synthetic microparticle RSV vaccine candidate.
Calder Biosciences will evaluate DT-preF, its lead RSV vaccine candidate, as part of a Phase I clinical trial that will include an efficacy read-out. Preclinical studies are designed to assess the toxicity and tolerability of the lead candidate vaccine. The preclinical study will begin in November 2023, and the Phase 1 clinical study will start in H1 2024.
RSV/6120/ΔNS2/1030s is a live-attenuated intranasal RSV vaccine candidate containing a deletion of the interferon antagonist NS2 gene and a genetically stabilized temperature-sensitivity mutation in the polymerase gene. It was infectious and induced primary neutralizing serum antibody responses and potent memory antibody responses in 6-to-24-month-old RSV-seronegative children but may be associated with rhinorrhea.
RSV Vaccines in China
RSV therapeutic candidates are in mainland China, Hong Kong, Macau, and Singapore. Sisunatovir is being evaluated for potentially treating RSV infection in pediatric and adult patients. Pfizer Inc. and LianBio announced on December 19, 2022, that Pfizer opted to develop and commercialize sisunatovir (RV521). The U.S. FDA granted Sisunatovir Fast Track Designation in 2020. In addition, it is being considered in a global phase 2 clinical study in children. On November 14, 2022, Nuance Pharma announced China's Center for Drug Evaluation approved its application supporting its pivotal phase IIMVA-BN RSV vaccine clinical trial.
RSV Vaccine Coadministration With Influenza Vaccine
According to the U.S. CDC, the available data on the immunogenicity of the coadministration of RSV and other vaccines is currently limited. The U.S. CDC presented the following coadministration information on September 19, 2023 - There is currently limited data on the immunogenicity of coadministration of RSV and other vaccines. In general, the coadministration of RSV and seasonal influenza vaccines met noninferiority criteria for immunogenicity. However, RSV and influenza antibody titers were generally somewhat lower with coadministration; the clinical significance of this is unknown. Additional studies on the immunogenicity of coadministration of RSV with other adult vaccines are being conducted. A draft, revised vaccine schedule addendum was presented on September 22, 2023.
RSV Vaccination Administration Errors
As of January 17, 2024. a Clinician Outreach and Communication Activity (COCA Now) email confirmed that the number of RSV vaccination error reports received by the U.S. HHS's VAERS in young children under two years of age was 25 and 128 by pregnant women.
RSV Vaccination Timing
The CDC confirmed in January 2024 that most of the continental U.S. could administer the maternal RSV vaccine from September through January 31. In jurisdictions where seasonality differs from that of most of the continental United States, such as Alaska, southern Florida, Guam, Hawaii, Puerto Rico, the U.S.-affiliated Pacific Islands, and the U.S. Virgin Islands, healthcare providers should follow state, local, or territorial guidance on the timing of administering the RSV vaccine (Pfizer Abrysvo) for pregnant women.
RSV Vaccine Price
The global RSV Therapeutics Market Size is estimated to reach about $836 million by 2028, exhibiting a CAGR of 5.76%. Additional RSV vaccine and treatment price information are posted at InstantRx™.
RSV Season 2024
The U.S. CDC, ECDC, and WHO report seasonal trends in RSV cases.
RSV Monoclonal Antibody
RSV monoclonal antibody therapies for children are U.S. FDA-approved as of July 2024.
RSV Vaccination Guillain-Barré Syndrome (GBS) Analysis
On Feb. 29. 2024, the U.S. CDC Advisory Committee on Immunization Practices (ACIP) meeting reviewed RSV vaccine efficacy and identified Guillain-Barré Syndrome (GBS) Risk Analysis, benefits and risks discussion, and ACIP Work Group interpretations and discussion.
