The purpose of this study is to characterize the immune response to the FDA-approved mRNA-based RSV vaccine in adults ≥60 years of age, using a systems biology approach. The study aims to generate high-resolution immunologic and systems biology data following vaccination to identify early biomarkers of response and gain mechanistic insight into host immunity.

Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract disease (LRTD) in older adults and individuals with chronic comorbidities. In response to this burden, several RSV vaccines have recently been licensed for use in adults ≥60 years of age, including products developed by Pfizer, GlaxoSmithKline (GSK), and Moderna. These vaccines represent distinct technological platforms - recombinant protein with adjuvant, bivalent prefusion F (preF) subunit, and messenger RNA (mRNA), respectively - each with demonstrated efficacy in large-scale clinical trials.

Understanding the immunological mechanisms and durability of protection across these platforms remains a major research priority, particularly given the increased use of next-generation vaccine technologies such as mRNA. Systems biology approaches, including transcriptomics, proteomics, metabolomics and advanced immune profiling, provide a powerful means to identify early biomarkers of immunogenicity and long-term antibody persistence. Such approaches have successfully revealed predictive immune signatures in response to a variety of vaccines.

In parallel studies, the researchers have collected samples from individuals who received the Pfizer and GSK RSV vaccines at retail pharmacies under routine clinical use. However, the mRNA-based RSV vaccine (MRESVIA, developed by Moderna) has been less widely deployed to date in community settings, limiting opportunities to collect samples prospectively under real-world conditions. As a result, the researchers are establishing this dedicated protocol to characterize the immune response to MRESVIA using a systems biology approach. Through comprehensive sampling at early and late timepoints post-vaccination, the researchers aim to define molecular and cellular features unique to the mRNA platform and identify early predictors of immune response magnitude and durability. These data will also support future cross-platform comparisons.

Inclusion Criteria:

• Adults ≥60 years of age at the time of enrollment.
• Able and willing to provide written informed consent.
• Eligible for receipt of an FDA-approved RSV vaccine (MRESVIA) per Advisory Committee on Immunization Practices (ACIP)/Centers for Disease Control and Prevention (CDC) guidelines.
• Available for all study visits and procedures, including follow-up through Day 180.
• Willing to allow access to prior RSV vaccination history (if applicable) for eligibility verification

Exclusion Criteria:

• History of severe allergic reaction (e.g., anaphylaxis) to any prior vaccines or any component of the MRESVIA vaccine, including polyethylene glycol (PEG), the amino lipid SM-102 (SM-102), or other listed excipients.

• Acute illness or fever (temperature ≥100.4°F) at the time of vaccination (participant may be rescheduled).

• Immunocompromising conditions, including:

  • Current cancer chemotherapy or immunosuppressive therapy.
  • History of hematologic malignancies or other immune-mediated diseases that would interfere with vaccine response.
  • Known or suspected HIV infection with cluster of differentiation 4 (CD4) count <200 or uncontrolled viremia.

• Clinically significant cardiac, pulmonary, renal, hepatic, or neurological disease that, in the opinion of the investigator, would preclude participation or confound interpretation of immune data.

• Uncontrolled autoimmune disorder.

• Current use of systemic corticosteroids equivalent to ≥20 mg prednisone daily for more than 14 consecutive days in the past month.

• History of Guillain-Barré Syndrome or other demyelinating neurological disorders.

• History of myocarditis, pericarditis, or myopericarditis within the last 2 months.

• Any bleeding disorder that poses a risk for venipuncture or vaccination complications.

• Participation in another clinical trial involving an investigational agent within 30 days of enrollment.

• Receipt or plan receipt of vaccines in the past an upcoming 28 days.

• Prior receipt of any RSV vaccine.

• Receipt of blood products or immune globulin within the prior 3 months.

• History of excessive alcohol consumption or drug use, or psychiatric/social/occupational conditions that may interfere with study compliance.

• Any other condition that, in the opinion of the investigator, may interfere with study conduct or participant safety.

De-identified individual participant data (IPD) will be shared upon reasonable request, following completion of primary analyses. Data that will be available for sharing include de-identified demographic, safety, and immunogenicity data, as well as omics datasets (e.g., transcriptomics, proteomics, metabolomics) collected pre- and post-vaccination. Data dictionaries will also be provided.

Data will become available within 12 months after publication of the primary results and will remain available for 5 years thereafter.

Data will be available for sharing with qualified researchers from academic, nonprofit, or governmental institutions, for the purposes of analyses consistent with advancing scientific knowledge in vaccinology and immunology. Requests will be reviewed by the study PI. Approved investigators will sign a data use agreement (DUA) and data will be shared through secure transfer methods.