The pharmaceutical company GSK has announced the availability in Spain of Arexvy, its new vaccine aimed at preventing lower respiratory tract diseases caused by respiratory syncytial virus (RSV) in people over 60 years of age, including those with pre-existing conditions.
RSV is a seasonal pathogen that spreads mainly through direct contact with infected secretions and is characterized by its high contagiousness. This virus can occur in two antigenic variants, RSV-A and RSV-B, and its outbreaks tend to occur in the coldest months of the year. RSV is significantly relevant in the context of public health due to its contribution to the so-called ‘tripledemia’, which also includes SARS-CoV-2 and influenza.
According to recent studies, the prevalence of Acute Respiratory Infections (ARIs) due to RSV in adults over 60 years of age is 1.62%. Applying this rate to the population over 60 years of age in Spain in 2022 according to the National Institute of Statistics (INE), there would be approximately 203,914 cases of RSV each year in this group.
Furthermore, the hospitalization rate in this age group is 0.15%, with an in-hospital mortality rate of 7.13%. This would translate into 19,117 hospitalizations and 1,363 deaths annually due to RSV in our country. It is important to highlight that, due to the limited availability of diagnostic tests to detect RSV and the lack of powerful surveillance systems, the available data are likely to be underestimated.
Vaccinate older adults to stop the spread of RSV
RSV infection is common at all stages of life, but is especially critical in newborns and older adults, where it can trigger serious complications such as pneumonia and exacerbation of chronic diseases, increasing the risk of hospitalization and death.
Iñaki Hernáez, medical director of GSK vaccines in Spain, has highlighted the effectiveness of the AS01 adjuvant, also used in the GSK vaccine against shingles, which has shown benefits in the immune response in older adults, especially in those with other pathologies.
The vaccine was approved by the US FDA on May 3, 2023 for the prevention of lower respiratory tract disease caused by RSV in people aged 60 years and older. It has since also been approved for use in the EU, the UK, Canada, Japan, Brazil, Hong Kong and the Philippines. The vaccine has been accepted for regulatory review by the European Medicines Agency (EMA) for the prevention of RSV in adults aged 50 to 59 years at increased risk. Currently the indication approved by the EMA is in adults 60 years and older.
“Vaccination against RSV in older adults could help protect people from severe cases and reduce the pressure on healthcare systems during periods of seasonal virus circulation”
Dr. Federico Martinón, head of the Pediatric Service at the University Clinical Hospital of Santiago and principal investigator of the pivotal study AReSVi-006, has highlighted the importance of vaccination in the adult population in the context of global aging. “We are facing an unprecedented aging population. Mathematical models project that by 2050, people over 60 years of age will represent 22% of the world’s population, an increase of 10 percentage points compared to 2015. These figures invite us to reflect on the importance of vaccination in older people. adult and work together to achieve similar vaccination rates in this group to those obtained in pediatric ages. In an increasingly aging society, vaccination against RSV in older adults could help protect people from severe cases and reduce the pressure on healthcare systems during periods of seasonal virus circulation.”
In terms of efficacy, Arexvy demonstrated 82.6% effectiveness against RSV lower respiratory tract disease in its first season and 67.2% after two seasons in older adults. In addition, it showed consistent results against the two subtypes of the virus, with an effectiveness of 84.6% and 80.9% against RSV-A and RSV-B, respectively, in the first season.
Finally, coadministration with other vaccines such as the quadrivalent influenza vaccine has been immunogenic and well tolerated, with mostly mild or moderate side effects that included pain at the injection site, fatigue, myalgia, headache and arthralgia, which disappeared after a few days. of vaccination.
