AREXVY™ RSV Vaccine Clinical Trials, Dosage, Efficacy, Indication, Side Effects
GlaxoSmithKline Biologicals plc (GSK) AREXVY™ recombinant, AS01E adjuvanted, single-dose RSV vaccine contains a recombinant subunit pre-fusion respiratory syncytial virus (RSV) glycoprotein antigen (RSVPreF3) combined with GSK's proprietary AS01 adjuvant. The antigen plus adjuvant combination helps overcome the natural decline in immunity that contributes to the challenge of protecting people from RSV disease. AREXVY contains Agenus' proprietary QS-21 STIMULON™ within its AS01 adjuvant, which has already demonstrated positive immune responses and a favorable safety profile. QS-21 Stimulon improves a vaccine's effectiveness by inducing strong antibody and cell-mediated immune responses. It also plays a crucial role in boosting immune response in older adults who often experience age-related decline in immunity.
On May 3, 2023, the U.S. Food and Drug Administration (FDA) approved Arexvy to prevent LRVD caused by RSV in individuals 60 and older in the U.S. (PRESCRIBING INFORMATION, Package Insert). On June 7, 2024, the FDA approved Arexvy for adults aged 50 through 59 who are at increased risk of RSV. As of October 2024, about 9 million people in the U.S. have been vaccinated with Arexvy. GSK says Arexvy is the only RSV vaccine with efficacy and safety data available through three full seasons, including in people at increased risk.
The European Medicines Agency (EMA) recommended marketing authorization in the European Union (EU) on April 26, 2023, for Arexvy for active immunization to protect adults aged 60 years and older against LRTD caused by RSV. The European Commission authorized Arexvy on June 7, 2023. The U.K.'s Medicines and Healthcare products Regulatory Agency authorized Arexvy on July 10, 2023, followed by Canada on August 4, 2023. On January 29, 2023, the EMA accepted the company's regulatory application to expand the use of Arexvy to adults aged 50-59 at increased risk for RSV disease. The EMA's Committee for Human Medicines (CHMP) issued a positive opinion for individuals aged 50-59 at increased risk of RSV disease on July 29, 2024.
On November 5, 2024, AREXVY was approved in Canada for the prevention of LRTD caused by RSV. As of January 2025, the U.S. CDC says RSV vaccines are recommended for all adults ages 75 and older and adults ages 60 – 74 who are at increased risk for severe RSV. The RSV vaccine is not currently an annual vaccine. If you have received an RSV vaccine, you should not get another RSV vaccine in 2025. On April 16, 2025, the Advisory Committee on Immunization Practices (ACIP) voted in favor of recommending the use of AREXVY in adults aged 50-59 who are at increased risk for severe RSV disease.
GlaxoSmithKline plc (LSE/NYSE: GSK) is located in Brentford, West London, England, and is a science-led global healthcare company. For further information, please visit www.gsk.com/about-us. AREXVY trademark was issued on November 15, 2022.
AREXVY Indication
Arexvy has been approved for certain adults.
AREXVY Immunocompromised Persons
A Research Letter published by the JAMA Network on December 30, 2024, indicated AREXVY (RSVA-AS01E ) produced better results in immunocompromised persons.
AREXVY Efficacy
Phase 3 clinical trial results indicate that after a single dose of GSK’s RSV vaccine, cumulative efficacy over three full RSV seasons was clinically meaningful at 62.9% against RSV-LRTD (97.5% CI, 46.7-74.8, 48 of 12,468 vs 215 of 12,498) and 67.4% against severe RSV-LRTD (95% CI, 42.4-82.7, 15 of 12,468 vs 75 of 12,498) compared to placebo. In the third season, the vaccine’s efficacy was 48.0% against RSV-LRTD (95% CI, 8.7-72.0, 16 of 4,988 vs 61 of 10,031).
AREXVY Coadministration With Shingrix
GSK plc announced on September 18, 2024, that a Phase 3 clinical trial (NCT05966090) met the primary endpoint of non-inferior immune response when administering RSVPreF3 OA and Shingrix vaccines compared with separate vaccinations.
AREXVY Coadministration of Influenza Vaccines
Available data on the immunogenicity of coadministration of RSV vaccines and other vaccines are currently limited, says the U.S. CDC. Administering an RSV vaccine with other vaccines might increase local or systemic reactogenicity, and RSV and influenza antibody titers were somewhat lower with coadministration; however, the clinical significance of this is unknown. GSK presented acceptable coadministration with influenza vaccine data to the U.S. FDA on March 1, 2023.
AREXVY Vaccine U.S. CDC ACIP Review
The U.S. CDC Advisory Committee on Immunization Practices (ACIP) conducted a review of RSV vaccines on April 16, 2025.
And on October 24, 2024. On June 26, 2024, including these presentations, on October 25, 2023. Camille Kotton, MD, presented an overview, Monica E. Patton, MD, presented the epidemiology of RSV hospitalizations in adults, and Amadea Britton, MD, MS, presented ACIP Adult RSV Work Group Considerations. On July 21, 2023, the CDC's Morbidity and Mortality Weekly Report confirmed the efficacy of 1 dose of the GSK vaccine in preventing symptomatic, laboratory-confirmed RSV-associated LRTD was 82.6% (96.95% CI = 57.9%–94.1%) during the first RSV season and 56.1% (95% CI = 28.2%–74.4%) during the second season. Efficacy of 1 dose over two seasons was 74.5% (97.5% CI = 60.0%–84.5%) in preventing RSV-associated LRTD and 77.5% (95% CI = 57.9%–89.0%) in preventing medically attended RSV-associated LRTD. Leonard Friedland, M.D. Vice President, Scientific Affairs and Public Health, GSK, presented updated data. The ACIP committee voted to recommend Arexvy for preventing RSV disease in adults aged 60 and older with shared clinical decision-making. The committee recommendations mean that over 55 million older adults in the U.S. could have access to RSV vaccination for the first time. On February 23, 2023, presentations included Ismael R. Ortega-Sanchez, Ph.D., presented - Economics of Vaccinating U.S. Adults ≥60 years old against RSV; Evidence to Recommendations Framework. On October 20, 2022, Bishoy Rizkalla, GSK Global Medical Affairs, presented an update to the CDC's vaccine committee.
AREXVY U.S. FDA Review
The FDA conducted a Vaccines and Related Biological Products Advisory Committee (VRBPAC) AREXVY review meeting for (STN 125775/0) on March 1, 2023. The FDA published the Briefing Document, GSK SPONSOR BRIEFING DOCUMENT, and Errata to the GSK Briefing Document. The committee voted unanimously (100%) that the data supported the effectiveness of the vaccine and 10-2 that the data supported the safety of the RSV vaccine. On November 2, 2022, GSK announced that the FDA had accepted a Biologics License Application (BLA) (STN 125775/0) and granted a Priority Review for the RSVPreF3 OA vaccine candidate.
AREXVY Availability 2025
As of April 2025, Arexvy was available in major retail pharmacies in the U.S. and is recommended in Europe, Malaysia, the United Kingdom, Quebec, Canada, Australia, and various countries.
AREXVY Dosage
Prescribing information was posted on May 3, 2023. Recent in-house results from a parallel Phase III trial, AReSVi 004, showed that in participants aged 60 years and above, one dose of the RSV OA investigational vaccine induced strong humoral and cellular immune responses that remained above pre-vaccination levels up to at least the six-month post-vaccination readout time point.
AREXVY Safety Data
On January 7, 2025, the FDA required and approved safety labeling changes to the Prescribing Information, which include a new warning about the risk of Guillain-Barré syndrome. GSK announced in October 2024 that the safety and reactogenicity data were consistent with those from the Phase III program. In Season 1, the vaccine was generally well-tolerated. The most frequently observed adverse events were pain at the injection site, fatigue, myalgia, headache, and arthralgia within four days of vaccination. Data to the U.S. FDA on March 1, 2023, indicating limited safety data following vaccination in multiple studies. The EMA confirmed on April 26, 2023, the most common side effects reported were headache, tiredness, muscle pain, joint pain, and injection site pain.
AREXVY Maternal Vaccine Candidate
Arexvy is not approved for use in individuals under 60 years of age. In a clinical study that enrolled pregnant individuals who received an investigational unadjuvanted RSV vaccine containing the same RSVPreF3 antigen as AREXVY, an increase in preterm births was observed compared to pregnant individuals who received a placebo (sucrose reconstituted with saline). In the vaccine and placebo groups, 6.81% and 4.95% of preterm births were reported, respectively. The maternal RSV candidate vaccine was tested in three doses compared with a placebo in 502 healthy, non-pregnant women, with monthly visits at Days 8, 31, and 91 post-immunization. The data show that compared with the base, the investigational vaccine rapidly boosted the pre-existing immunity at all doses, leading to high levels of protective neutralizing antibodies. On Day 8, a 14-fold increase in RSV-A and RSV-B neutralizing antibody titers was observed. As of May 27, 2023, this product was on hold.
AREXVY Cost
GSK plc announced on August 17, 2023, that Arexvy costs will be covered by most U.S. Medicare and commercial insurance plans under the Inflation Reduction Act, and patients with Medicare Part D will pay no out-of-pocket expenses. As part of the Affordable Care Act, AREXVY may be covered for commercially insured patients at no cost when administered in-network.
AREXVY Vaccine News
April 16, 2025 - Tony Wood, Chief Scientific Officer, GSK commented: “We are pleased with ACIP's recommendation to expand the benefits of RSV immunization to more than 13 million adults aged 50-59 who are at increased risk for the severe consequences of this virus. RSV can have a significant impact for those with underlying medical conditions. We look forward to helping protect more people with RSV vaccination.”
October 24, 2024 - Tony Wood, Chief Scientific Officer, GSK, said in a press release, “We’re committed to working with health authorities and regulators to help adults at increased risk of RSV disease benefit from vaccination.”
October 8, 2024 - Tony Wood, Chief Scientific Officer, GSK, said: “We are excited by these new data, which show that a single dose of AREXVY could help protect millions of older adults at risk of RSV disease over three seasons, benefiting public health."
September 18, 2024 - Len Friedland, MD, Vice President of Scientific Affairs and Public Health, GSK, said in a press release, "We are excited to share data on the co‑administration of our RSV and shingles vaccines."
June 7, 2024 - Tony Wood, Chief Scientific Officer, GSK, said: “Today's approval reflects the importance of broadening the benefits of RSV immunization to adults aged 50-59 who are at increased risk. For those with underlying medical conditions, RSV can have serious consequences, so we are proud to be the first to help protect them from RSV-LRTD.”
April 26, 2023 - The EMA recommended a marketing authorization in the European Union for Arexvy.
June 10, 2022 - GSK plc announced positive headline results from a pre-specified efficacy interim analysis of the AReSVi 006 phase III trial. The interim analysis indicates the primary endpoint was exceeded, with no unexpected safety concerns observed.
November 23, 2020 - GlaxoSmithKline plc announced that patient dosing had begun in phase 3 clinical program investigating the safety and efficacy of its RSV candidate vaccine for maternal immunization (GSK3888550A) following the presentation of positive phase 1/2 safety, reactogenicity, and immunogenicity data last month
RSV OA Vaccine Clinical Trials
The GSK RSVPreF3 RSV vaccine has been involved in various clinical studies.
GSK announced positive phase III trial results for its RSV vaccine, demonstrating an overall vaccine efficacy of 82.6% (96.95% CI, 57.9–94.1, 7 of 12,466 vs. 40 of 12,494) against RSV lower respiratory tract disease (RSV-LRTD), meeting the AReSVi 006's primary endpoint. On February 16, 2023, the NEJM published an ORIGINAL ARTICLE: Respiratory Syncytial Virus Prefusion F Protein Vaccine in Older Adults. Findings: A single dose of the RSVPreF3 OA vaccine had an acceptable safety profile in a phase 3 study and prevented RSV-related acute respiratory infection and lower respiratory tract disease and severe RSV-LRTD in adults 60 years of age or older, regardless of RSV subtype and the presence of the underlying coexisting condition. GSK funded the AReSVi-006 ClinicalTrials.gov NCT04886596.
On October 25, 2023, GSK announced preliminary results from a phase III clinical trial showing that the primary endpoints had been met, with non-inferior immune responses observed in adults aged 50-59 compared to adults aged 60 and older. Adults aged 50 and above with certain underlying medical conditions are at increased risk for RSV disease. GSK is on track to being the first company to submit data in this population to regulators, with decisions on potential label expansion expected in 2024.
The AReSVi-006 (Adult Respiratory Syncytial Virus) phase III trial is a randomized, placebo-controlled, observer-blind, multi-country demonstrating the efficacyGSK's single dose of GSK's adjuvanted RSVPreF3 OA investigational vaccine in adults aged 60 years and above. Approximately 25,000 participants from 17 countries were enrolled. AReSVi 006 is a phase III trial. Last Update Posted: June 30, 2022.
Results: 24,966 participants received one dose of the RSVPreF3 OA vaccine (12,467 participants) or placebo (12,499). Over a median follow-up of 6.7 months, vaccine efficacy against RT-PCR–confirmed RSV-related lower respiratory tract disease was 82.6% (96.95% confidence interval [CI], 57.9 to 94.1), with 7 cases (1.0 per 1000 participant-years) in the vaccine group and 40 patients (5.8 per 1000 participant-years) in the placebo group. Vaccine efficacy was 94.1% (95% CI, 62.4 to 99.9) against severe RSV-related lower respiratory tract disease (assessed based on clinical signs or by the investigator) and 71.7% (95% CI, 56.2 to 82.3) against RSV-related acute respiratory infection. Vaccine efficacy was similar against the RSV A and B subtypes (for RSV-related lower respiratory tract disease: 84.6% and 80.9%, respectively; for RSV-related acute respiratory infection: 71.9% and 70.6%, respectively). In addition, high vaccine efficacy was observed in various age groups in participants with coexisting conditions. The RSVPreF3 OA vaccine was more reactogenic than the placebo, but most adverse events for which reports were solicited were transient, with mild-to-moderate severity. The incidences of serious adverse events and potential immune-mediated diseases were similar in the two groups.
