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Safety, Tolerability, and Immunogenicity Study of a 24-Valent Pneumococcal Conjugate Vaccine (VAX-24) in Older Adults

Phase 2
Completed
Conditions
Pneumococcal Vaccines
Interventions
Biological: 24-Valent Pneumococcal Conjugate Vaccine
Registration Number
NCT05297578
Lead Sponsor
Vaxcyte, Inc.
Brief Summary

The objective of the study is to evaluate the safety and tolerability of a single injection of VAX-24 at 3 dose levels compared to Prevnar 20™ (PCV20) in adults 65 years of age and older.

Detailed Description

The objective of the study is to evaluate the safety and tolerability of a single injection of VAX-24 at 3 dose levels (Low: 1.1 mcg; Mid: 2.2 mcg; or Mixed: 2.2/4.4 mcg) compared to Prevnar 20™ (PCV20) in adults 65 years of age and older.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
207
Inclusion Criteria
  • Male or female age 65 or older.
  • Able and willing to complete the informed consent process.
  • Available for clinical follow-up through the last study visit at 6 months after the study vaccination.
  • In good general health as determined by medical history, vital signs, physical examination, and clinical judgment of the investigator. Preexisting medical conditions must be stable as defined by no change in treatment at least 6 weeks prior to study participation.
  • Willing to have blood samples collected, stored indefinitely, and used for research purposes.
  • Able to provide proof of identity to the satisfaction of the study staff completing the enrollment process.
Exclusion Criteria
  • Previous pneumococcal disease (either confirmed or by self-reporting).
  • Previous receipt of a licensed or investigational pneumococcal vaccine.
  • Receipt of any investigational study product within 30 days prior to enrollment into the study, currently participating in another interventional investigational study, or having plans to receive another investigational product(s) while on study.
  • Planned or actual administration of any licensed vaccine during the period starting 30 days before enrollment into the study through Day 29.
  • Physical examination indicating any clinically significant medical condition.
  • Body Temperature > 38.0°C (> 100.4°F) or acute illness within 3 days prior to study vaccination (subject may be rescheduled).
  • Previous or existing diagnosis of HIV, Hepatitis B or Hepatitis C.
  • History of severe allergic reaction with generalized urticaria, angioedema, or anaphylaxis.
  • Bleeding disorder diagnosed by a doctor (eg, factor deficiency, coagulopathy, or platelet disorder requiring special precautions) or significant bruising or bleeding difficulties with intramuscular injections or blood draws.
  • Any other chronic or clinically significant medical condition that, in the opinion of the investigator, would jeopardize the safety or rights of the subject or confound evaluation of the study vaccine.
  • Any medical, psychiatric, or social condition that, in the judgment of the investigator, is a contraindication to protocol participation or impairs a subject's ability to give informed consent.
  • Received blood or blood product (including Immune Globulin IV) within 90 days prior to enrollment into the study.
  • Received systemic corticosteroids for ≥ 14 consecutive days and has not completed treatment ≤30 days prior to enrollment into the study.
  • Receiving immunosuppressive therapy.
  • History of malignancy ≤5 years before enrollment, except for adequately treated basal cell or squamous cell skin cancer or in situ cervical cancer.

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
VAX-24 Low Dose24-Valent Pneumococcal Conjugate VaccineParticipants will receive a single dose of VAX-24 1.1 mcg administered as an intramuscular injection on Day 1.
VAX-24 Mid Dose24-Valent Pneumococcal Conjugate VaccineParticipants will receive a single dose of VAX-24 2.2 mcg administered as an intramuscular injection on Day 1.
VAX-24 Mixed Dose24-Valent Pneumococcal Conjugate VaccineParticipants will receive a single dose of VAX-24 2.2 mcg/4.4 mcg administered as an intramuscular injection on Day 1.
PCV20Pneumococcal 20-valent Conjugate VaccineParticipants will receive a single intramuscular injection of the standard dose of PCV20 on Day 1.
Primary Outcome Measures
NameTimeMethod
Percentage of Participants Reporting SAEs and New Onset of Chronic Illnesses (NOCIs)6 months after vaccination

Percentage of participants with serious adverse events (SAEs) and new onset of chronic illness (NOCIs)

Percentage of Subjects Reporting Unsolicited Adverse Events Within 1 Month After Vaccination1 month after vaccination

Percentage of participants with at least one Treatment Emergent Adverse Event (unsolicited AEs and SAEs)

Percentage of Participants Reporting Solicited Local Reactions Within 7 Days After Vaccination7 days after vaccination

Solicited local reactions included redness/erythema, swelling/induration, and pain at injection site

Percentage of Participants Reporting Solicited Systemic Events Within 7 Days After Vaccination7 days after vaccination

Solicited systemic reactions include fever, headache, fatigue, muscle pain, and joint pain within 7 days of vaccination

Secondary Outcome Measures
NameTimeMethod
24 VAX-24 Pneumococcal Serotype-specific IgG Geometric Mean Concentration (GMCs)1 month after vaccination

The change from baseline to 1 month post-vaccination in the immune response directed against each of the 24 serotypes was evaluated by measuring IgG levels using an IgG multiplexed electrochemoluminescent assay (ECLA). Values below the lower limit of quantitation (LLOQ) were analyzed as 0.5\*LLOQ. Values above the upper limit of quantitation (ULOQ) were analyzed as 1\*ULOQ.

VAX-24 Pneumococcal Serotype-specific Opsonophagocytic Assay (OPA) Geometric Mean Titer (GMTs)1 month after vaccination

The change from baseline to 1 month post-vaccination in the immune response directed against each of the 24 serotypes was evaluated by measuring serotype-specific functional antibody responses with an opsonophagocytic (OPA) assay that assesses the functional capacity of pneumococcal antibodies.

Trial Locations

Locations (18)

Accel Research Sites - DeLand Clinical Research Unit

🇺🇸

DeLand, Florida, United States

Accellacare of Rocky Mount

🇺🇸

Rocky Mount, North Carolina, United States

Healthcare Research Network

🇺🇸

Hazelwood, Missouri, United States

Charlottesville Medical Research

🇺🇸

Charlottesville, Virginia, United States

Precision Clinical Research

🇺🇸

Sunrise, Florida, United States

Pivotal Research Solutions

🇺🇸

Stonecrest, Georgia, United States

Healthcare Research Network II, LLC

🇺🇸

Flossmoor, Illinois, United States

AMR Wichita West

🇺🇸

Wichita, Kansas, United States

Velocity Clinical Research, Salt Lake City

🇺🇸

West Jordan, Utah, United States

CenExel RCA

🇺🇸

Hollywood, Florida, United States

Meridian Clinical Research

🇺🇸

Cincinnati, Ohio, United States

Coastal Carolina Research

🇺🇸

North Charleston, South Carolina, United States

Clinical Trials of Texas, LLC

🇺🇸

San Antonio, Texas, United States

CenExel JBR Clinical Research

🇺🇸

Salt Lake City, Utah, United States

AMR Newton, formerly Heartland Research Associates

🇺🇸

Newton, Kansas, United States

AMR New Orleans

🇺🇸

New Orleans, Louisiana, United States

Accellacare of Charleston

🇺🇸

Mount Pleasant, South Carolina, United States

Accel Research Sites-Birmingham Clinical Research Unit

🇺🇸

Birmingham, Alabama, United States

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