ABSTRACT
BACKGROUND: Co-administration of vaccines against respiratory syncytial virus (RSV) and influenza can be considered given their overlapping seasonality, and may increase vaccine uptake and compliance. In this phase 3, open-label, randomized study, we evaluated the immunogenicity, reactogenicity, and safety of the AS01E-adjuvanted RSV prefusion F protein-based candidate vaccine (RSVPreF3 OA) when co-administered with a seasonal quadrivalent influenza vaccine (FLU-QIV) in older adults. METHODS: Participants aged ≥60 years (randomized 1:1) received either RSVPreF3 OA and FLU-QIV simultaneously on day 1 (Co-Ad group) or FLU-QIV on day 1 followed by RSVPreF3 OA on day 31 (sequential administration [SA] group). The co-primary objectives were to demonstrate noninferiority of RSVPreF3 OA in terms of RSV-A neutralization geometric mean titer (GMT) ratio and FLU-QIV in terms of hemagglutination inhibition GMT ratio for each FLU-QIV strain, when co-administered versus when administered alone at 1-month post-vaccination. Noninferiority was demonstrated if the upper limit of the 95% confidence interview of the group GMT ratio (SA/Co-Ad) was ≤1.5. Secondary descriptive objectives comprised additional immunogenicity assessments, reactogenicity, and safety. RESULTS: Of the 885 participants who received one dose of the study vaccines, 837 were included in the per protocol set. Demographic and baseline characteristics were balanced between the groups. Both co-primary objectives were met for both vaccines. Reported adverse events in both groups were mild-to-moderate, with a low frequency of grade 3 events. CONCLUSIONS: Data from this study demonstrate that RSVPreF3 OA can be co-administered with FLU-QIV. Co-administration is well tolerated, with an acceptable safety profile. CLINICALTRIALS.GOV REGISTRATION: NCT04841577.
ABSTRACT
BACKGROUND: The recently approved AS01E-adjuvanted respiratory syncytial virus (RSV) prefusion F protein-based vaccine (RSVPreF3 OA) demonstrated high efficacy against RSV-related disease in ≥60-year-olds. METHODS: This ongoing phase 3 study in ≥60-year-olds evaluates the immune persistence until three years post-RSVPreF3 OA vaccination. Here, we describe interim results on humoral and cell-mediated immunogenicity, reactogenicity, and safety until one year post-dose 1. RESULTS: In total, 1653 participants were vaccinated. One month post-dose 1, neutralization titers increased 10.5-fold (RSV-A) and 7.8-fold (RSV-B) versus pre-dose 1. Titers then declined to levels 4.4-fold (RSV-A) and 3.5-fold (RSV-B) above pre-dose 1 at month 6, and remained 3.1-fold (RSV-A) and 2.3-fold (RSV-B) above pre-dose 1 levels after one year. RSVPreF3-binding immunoglobulin G levels and CD4+ T-cell frequencies showed similar kinetics. Solicited administration-site and systemic adverse events (mostly mild to moderate and transient) were reported by 62.2% and 49.5% of participants. Serious adverse events were reported by 3.9% of participants within 6 months post-dose 1; one case was considered vaccine-related. CONCLUSIONS: One RSVPreF3 OA dose elicited cell-mediated and RSV-A and RSV-B-specific humoral immune responses that declined over time but remained above pre-dose 1 levels for at least one year. The vaccine was well tolerated with an acceptable safety profile.Clinicaltrials.gov NCT04732871.
Respiratory syncytial virus (RSV) is a major cause of illness and hospitalization in older adults. An RSV vaccine for older adults developed by GSK was recently approved. The vaccine was well tolerated and provided protection against RSV disease in adults aged 60 years and older during at least one RSV season. In this ongoing study, we are evaluating the magnitude and durability of the immune response, as well as vaccine safety, until three years after vaccination of adults aged 60 years and older from five countries. Here, we report the results of an interim analysis until one year after vaccination with one dose. In total, 1653 participants were vaccinated. We found that the vaccine induced a strong immune response that was evident one month after vaccination, after which it declined, but persisted for at least one year. Study participants most often reported pain at the injection site, muscle pain, tiredness, and headache as adverse reactions, which were mostly mild to moderate and of short duration. One serious adverse reaction was considered related to the vaccine. The long-term immune response that was observed in this study is consistent with the vaccine providing protection during at least one RSV season.
