GSK plc (LSE/NYSE: GSK) has announced new findings from the AReSVi-006 Phase III trial, which assessed the effectiveness of a single dose of Arexvy, a recombinant adjuvanted vaccine for respiratory syncytial virus (RSV), against lower respiratory tract disease (LRTD) in adults aged 60 and older, including those at higher risk. This trial evaluated data over three RSV seasons (NCT04886596) and the results will be shared at the CHEST 2024 Annual Meeting organized by the American College of Chest Physicians.
Arexvy is recognized as the world’s first RSV vaccine, having received approval based on its outstanding efficacy in older adults, particularly those with underlying health conditions. The latest results show a cumulative efficacy of 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) after one dose compared to a placebo. In the third season, the vaccine demonstrated an efficacy of 48.0% against RSV-LRTD (95% CI, 8.7-72.0, 16 of 4,988 vs 61 of 10,031).
The study results include effectiveness against various RSV subtypes in older adults (ages 70-79) and those with specific underlying health conditions. Given that RSV can worsen existing medical issues and lead to hospitalizations, the cumulative efficacy over three seasons suggests a significant potential health impact. The findings may provide healthcare professionals with the flexibility to administer the vaccine throughout the year. To maintain optimal protection, revaccination will likely be necessary over time. GSK will continue to share data on efficacy and immune responses, including revaccination insights, to guide immunization schedules and future recommendations.
RSV is a highly contagious virus affecting the lungs and respiratory passages, impacting approximately 64 million people worldwide each year. Older adults, especially those with comorbidities or weakened immune systems, are at increased risk for RSV-related complications. The virus can exacerbate various conditions such as COPD, asthma, and chronic heart failure, potentially resulting in severe outcomes like pneumonia, hospitalization, and death. In high-income countries, RSV contributes to over 465,000 hospitalizations and 33,000 deaths annually among adults aged 60 and older.
Tony Wood, Chief Scientific Officer at GSK, commented, “We are encouraged by these new data showing that a single dose of Arexvy could help protect millions of at-risk older adults over three seasons, ultimately benefiting public health. This is the only RSV vaccine with proven efficacy and safety data spanning three full seasons. We will continue to provide long-term follow-up data to aid recommending bodies in establishing future revaccination schedules.” He also noted that the safety and reactogenicity data aligned with previous Phase III results, indicating that the vaccine was generally well tolerated in the first season, with the most common side effects being injection site pain, fatigue, myalgia, headache, and arthralgia within four days of vaccination.
In addition to the CHEST presentation, GSK plans to submit the data for peer-reviewed publication and regulatory review.