Efficacy by RSV Type,
Severity, and Age

RSV-LRTD by Subtypes


Efficacy against RSV A-LRTD1
(95% CI, 32.1, 98.3)


Efficacy against RSV B-LRTD1
(95% CI, 49.4, 94.3)



Efficacy against severe RSV-LRTD1
(95% CI, 62.4, 99.9)

AREXVY (1 case out of 12,466),
placebo (17 cases out of 12,494)

Subgroup Analysis for Participant’s Age


Efficacy against RSV-LRTD in participants aged 60-69 years1
(95% CI, 43.6, 95.3)

AREXVY (4 cases out of 6963),
placebo (21 cases out of 6979)


Efficacy against RSV-LRTD in participants aged 70-79 years1
(95% CI, 60.2, 99.9)

AREXVY (1 case out of 4487),
placebo (16 cases out of 4487)

The vaccine efficacy in the subgroup of participants 80 years of age and older (1016 participants in the AREXVY group vs 1028 in the placebo group) cannot be concluded due to the low number of total cases accrued (2 cases among participants who received AREXVY and 3 cases among participants who received placebo).1


    The efficacy of AREXVY against respiratory syncytial virus–associated lower respiratory tract disease (RSV-LRTD) was evaluated in an ongoing, phase 3, randomized, placebo-controlled, observer-blind study in adults aged 60 years and older in 17 countries from Northern and Southern Hemispheres. The primary population for efficacy analysis (referred to as the modified exposed set) included adults aged 60 years and older receiving 1 dose of AREXVY or placebo and who did not report an RSV-confirmed acute respiratory illness (ARI) prior to Day 15 after vaccination. Participants received 1 dose of AREXVY (n=12,466) or placebo (n=12,494). At the time of the primary efficacy analysis, participants had been followed for the development of RSV-associated LRTD for up to 10 months (median of 6.7 months). At the time of first efficacy analysis, the median age of participants was 69 years. At baseline, 39.3% of patients had at least 1 comorbidity of interest. Participants with pre-existing, chronic, stable disease such as diabetes, hypertension, or cardiac disease were allowed to participate in the study if considered by the investigator as medically stable at the time of vaccination. Immunocompromised participants were excluded.

    The primary objective was to demonstrate the efficacy of AREXVY in the prevention of a first episode of confirmed RSV-A and/or B-associated LRTD during the first season. Confirmed RSV cases were determined by quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) on a nasopharyngeal swab during all ARI episodes.

    ARI was defined by the presence of at least 2 respiratory symptoms/signs for at least 24 hours (nasal congestion, sore throat, lower respiratory symptoms/signs), or at least 1 respiratory symptom/sign plus 1 systemic symptom/sign (fever or feverishness, fatigue, body aches, headache, decreased appetite) for at least 24 hours.

    LRTD was defined as at least 2 lower respiratory symptoms/signs, including at least 1 lower respiratory sign for at least 24 hours, or at least 3 lower respiratory symptoms for at least 24 hours. Lower respiratory symptoms included: new or increased sputum, new or increased cough, new or increased dyspnea (shortness of breath). Lower respiratory signs included: new or increased wheezing, crackles/rhonchi, respiratory rate ≥20 respirations/min, low or decreased oxygen saturation (O2 saturation <95% or ≤90% if baseline is <95%), and need for oxygen supplementation.

    A severe RSV-associated LRTD was defined as an RT-PCR–confirmed RSV-associated LRTD with at least 2 lower respiratory signs or as an RT-PCR–confirmed RSV-associated LRTD episode preventing normal, everyday activities.1

Demonstrated Safety Profile

See the AREXVY safety data