Janssen RSV Protein Vaccine Displays Long-Term Efficacy Among ...

The Ad26.RSV.preF-RSV protein in Janssen's RSV vaccine displayed high efficacy in protecting individuals against respiratory syncytial virus (RSV)-associated lower respiratory tract disease (LRTD) throughout 3 RSV seasons, according to research published in The Lancet Infectious Diseases.1

Ad26.RSV.preF is a “recombinant, replication-incompetent, adenovirus type 26 (Ad26) vector encoding a stabilized RSV prefusion F (preF) protein,” the authors wrote. The protein can neutralize antibodies against RSV, according to study authors.1

RSV is known to cause severe LRTD among older adults, particularly those with chronic cardiac or lung conditions.1 For instance, according to results of a study published in JAMA Internal Medicine, acute cardiac events are common among older adults hospitalized due to RSV. In most cases, RSV was reported to cause mild upper respiratory tract symptoms, but can cause severe LRTD in high-risk groups, like older adults.2

The study authors noted that RSV causes around 5.2 million infections, 47,000 hospitalizations, and 33,000 in-hospital deaths annually. Among adults 60 years and older, 8.18% of hospitalized cases result in fatality, in relation to acute functional decline. Individuals who experience declines caused by the illness require medical resource utilization (MRU) and face high health care costs.1

To decrease MRU and the economic burden caused by RSV, the researchers believe a vaccine that can protect individuals for multiple seasons could be beneficial. However, the study authors noted that induction of tolerable immunity against RSV is challenging among older adults.1 The RSV season typically starts in the fall in the US and peaks in the winter months.3

In this latest study, the randomized, double-blind, placebo-controlled, phase 2b, proof-of-concept CYPRESS trial aimed to assess the use of Ad26.RSV.preF–RSV preF protein, compared to a placebo injection.1

The trial began enrollment on August 1, 2019, and included data collected until April 30, 2022, including 6672 adults aged 65 years and older from 40 clinical research centers in the US. Among the 6672 participants, approximately 5782 were randomly assigned 1:1 to receive the vaccine or the placebo. The study authors noted that the primary endpoint included the first occurrence of RSV-mediated LRTD, meeting 1 of 3 case definitions.1

Among the 5782 participants, 2124 received the vaccine and 2126 received the placebo in season 2, whereas 846 received the vaccine and 881 received the placebo in season 3. The findings demonstrated that vaccine efficacy to protect against RSV LRTD was 76.1% over seasons 2 and 3, and 78.7% across all 3 seasons, according to study authors.1

“In this study, 1 dose of the Ad26.RSV.preF–RSV preF protein vaccine showed sustained protective efficacy against RSV-mediated LRTD in adults aged 65 years or older through RSV seasons 2 and 3,” noted study authors in a news release.2

Serious adverse events were reported in 2.1% and 1.3% of the vaccine group and 2.1% and 1.1% among the placebo group during seasons 2 and 3, respectively, according to study authors. No serious treatment-related or fatal adverse events were reported in either group.1

The findings suggest that Ad26.RSV.preF–RSV preF protein displayed recurrent high efficacy to against RSV LRTD among older adults in 3 RSV seasons.1

References1. Long-term efficacy and immunogenicity of Ad26.RSV.preF–RSV preF protein vaccine (CYPRESS): a randomised, double-blind, placebo-controlled, phase 2b study. Science Direct. News release. May 24, 2024. Accessed June 7, 2024. https://www.sciencedirect.com/science/article/abs/pii/S1473309924002263.2. Research Suggests Acute Cardiac Events Are Common in Older Adults Hospitalized With RSV. Pharmacy Times. News release. April 30, 2024. Accessed June 7, 2024. https://www.pharmacytimes.com/view/research-suggests-acute-cardiac-events-are-common-in-older-adults-hospitalized-with-rsv.3. Study: Outcomes of RSV Associated with Acute Respiratory Failure. Pharmacy Times. News release. May 22, 2024. Accessed June 7, 2024. https://www.pharmacytimes.com/view/study-outcomes-of-rsv-associated-with-acute-respiratory-failure.