Respiratory Syncytial Virus (RSV) Vaccines 2024
Developing respiratory syncytial virus (RSV) vaccines was a priority of the World Health Organization (WHO) that began in the 1960s. As of January 2024, RSV vaccines have been approved in Canada, Europe, Japan, the United States, and the United Kingdom. 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 adults 60 years and older and pregnant women receive a single dose of an RSV vaccine based on discussions with healthcare providers and under certain conditions.
RSV Vaccines Approved in the U.S.
AREXVY™ RSV vaccine is approved for adults aged 60 and above. AREXVY became available in U.S. pharmacies on August 17, 2023.
ABRYSVO™ RSVpreF RSV bivalent vaccine from Pfizer Inc. received U.S. FDA and European Commission Approval for older adults and pregnant women during RSV season.
RSV Vaccine Efficacy
TD Cowen analyst Tyler Van Buren published a research abstract on February 8. 2024, that highlights significant decreases in RSV vaccine and RSV vaccine candidate efficacy. GSK's RSV vaccine experienced a 7% decline in efficacy after 14 months, a contrast to Moderna's vaccine's 25% decrease.
RSV Vaccination Trends 2024
As of February 17, 2024, the CDC estimated the percentage of people receiving an RSV vaccine. The National Immunization Survey findings for adults 60+ was 21.9% (20.9-22.9). The CDC's RSVVaxView reported that among pregnant women, the overall RSV vaccination rate was 16.2%
RSV Vaccine Reviews - U.S. CDC
On September 22, 2023, the U.S. CDC's Advisory Committee on Immunization Practices (ACIP) conducted an RSV review and voting session. On June 21, 2023, Camille Kotton, MD, presented an Adult RSV vaccine review session during the ACIP meeting. Alejandra Gurtman, MD, FIDSA, Pfizer, presented data, as did Leonard Friedland, MD, Vice President, Scientific Affairs and Public Health, GSK, who presented RSV vaccine updates. Michael Melgar, MD, led the Evidence to Recommendations Framework and Clinical Considerations for RSV Vaccines presentations. David W. Hutton, Ph.D., MS., and Ismael R. Ortega-SanchPh.D.Ph.D, directed the RSV Economic Analysis review. NCIRD/CDC led the SUMMARY COMPARING MODELS (cost-effectiveness) from GSK, Pfizer, and the University of Michigan-CDC. The ACIP voted 9 to 5, recommending people 60 and older receive an RSV vaccine using shared clinical decision-making in 2023. On June 22, 2023, the U.S. CMS confirmed these RSV vaccines would be included in Medicare Part D plans.
RSV Vaccine Candidates
Various pharmaceutical companies are conducting phase 3 clinical trials on RSV vaccine candidates.
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 December 12, 2023, Clover announced that enrollment of the first participants had been completed in a Phase 1 first-in-human study.
mRNA-1345 is a vaccine candidate against RSV developed by ModernaTX, Inc., encoding for a prefusion F glycoprotein, eliciting a superior neutralizing antibody response compared to the postfusion state. Based on the ConquerRSV Phase 3 pivotal efficacy trial, Moderna submitted marketing authorization applications for mRNA-1345 with the European Medicines Agency, Swissmedic, and the Therapeutic Goods Administration in Australia. The Company has also initiated a rolling submission to the U.S. FDA for a Biologics License Application for mRNA-1345. And mRNA-1345 is being investigated in a fully enrolled, ongoing Phase 1 trial in pediatric populations. On December 14, 2023, results from a phase 2/3 clinical trial indicated that a single dose of the mRNA-1345 led to a lower incidence of RSV-associated lower respiratory tract disease and RSV-associated acute respiratory disease than placebo among adults 60 or older.
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.
BLB201 is a single-dose intranasal vaccine that induces serum antibody and mucosal antibody responses as well as cell-mediated immune responses for the prevention of RSV infection from Blue Lake Biotechnology, Inc. BLB-201 is based on an attenuated strain of canine parainfluenza virus and expresses the RSV-F protein and is conducting a phase 1 study of CPI-RSV-F Vaccine (BLB-201). On November 7, 2022, the first study cohort showed that 64% of subjects had increased serum anti-RSV antibody responses above baseline levels. Therefore, the FDA granted Fast Track status on May 24, 2022.
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 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 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 Vaccination in Pregnant Women
The CDC says the RSV vaccine should be administered during weeks 32 through 36 of pregnancy. In most of the continental U.S., the RSV vaccine should be administered from September through January. The Journal of Infectious Diseases published a meta-analysis that found a 3.4% estimated prevalence of RSV infection during pregnancy.
RSV Vaccine Coadministration With Influenza Vaccine
Available data on the immunogenicity of coadministration of RSV and other vaccines is currently limited, says the U.S. CDC. 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 in process. 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 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 timing of administering the RSV vaccine (Pfizer Abrysvo) for pregnant people.
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 RSV has seasonality trends. The Bill & Melinda Gates Foundation and Gavi, the Vaccine Alliance, are working to improve access to RSV vaccines in low- and middle-income countries.
RSV Monoclonal Antibody
RSV monoclonal antibody therapies for children are U.S. FDA-approved as of 2024.