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

A Phase 2, Randomized, Observer-Blind, Dose-Finding, Controlled Clinical Study to Evaluate the Safety, Tolerability, and Immunogenicity of a 24-Valent Pneumococcal Conjugate Vaccine (VAX-24) in Healthy Adults 65 Years and Older

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.

Study Overview

• Status: Completed
• Conditions: Pneumococcal Vaccines
• Intervention / Treatment: Biological: 24-Valent Pneumococcal Conjugate Vaccine; Biological: Pneumococcal 20-valent Conjugate Vaccine

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.

• Study Type: Interventional
• Enrollment (Actual): 207
• Phase: Phase 2

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Birmingham, Alabama, United States, 35216
      • Accel Research Sites-Birmingham Clinical Research Unit
  • Florida
    • DeLand, Florida, United States, 32720
      • Accel Research Sites - DeLand Clinical Research Unit
    • Hollywood, Florida, United States, 33024
      • CenExel RCA
    • Sunrise, Florida, United States, 33351
      • Precision Clinical Research
  • Georgia
    • Savannah, Georgia, United States, 31406
      • Meridian Clinical Research
    • Stonecrest, Georgia, United States, 30038
      • Pivotal Research Solutions
  • Illinois
    • Flossmoor, Illinois, United States, 60422
      • Healthcare Research Network II, LLC
  • Kansas
    • Newton, Kansas, United States, 67114
      • AMR Newton, formerly Heartland Research Associates
    • Wichita, Kansas, United States, 67205
      • AMR Wichita West
  • Louisiana
    • New Orleans, Louisiana, United States, 70119
      • AMR New Orleans
  • Missouri
    • Hazelwood, Missouri, United States, 63042
      • Healthcare Research Network
  • Nebraska
    • Omaha, Nebraska, United States, 68134
      • Meridian Clinical Research
  • North Carolina
    • Rocky Mount, North Carolina, United States, 27804
      • Accellacare of Rocky Mount
  • Ohio
    • Cincinnati, Ohio, United States, 45219
      • Meridian Clinical Research
  • South Carolina
    • Mount Pleasant, South Carolina, United States, 29464
      • Accellacare of Charleston
    • North Charleston, South Carolina, United States, 29405
      • Coastal Carolina Research
  • Texas
    • San Antonio, Texas, United States, 78229
      • Clinical Trials of Texas, LLC
  • Utah
    • Salt Lake City, Utah, United States, 84107
      • CenExel JBR Clinical Research
    • West Jordan, Utah, United States, 84088
      • Velocity Clinical Research, Salt Lake City
  • Virginia
    • Charlottesville, Virginia, United States, 22911
      • Charlottesville Medical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 65 years and older (Older Adult)
• Accepts Healthy Volunteers: Yes

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: VAX-24 Low Dose; Participants will receive a single dose of VAX-24 1.1 mcg administered as an intramuscular injection on Day 1.	Biological: 24-Valent Pneumococcal Conjugate Vaccine; 0.5 ml dose of VAX-24 will be administered into the deltoid muscle at Day 1
Experimental: VAX-24 Mid Dose; Participants will receive a single dose of VAX-24 2.2 mcg administered as an intramuscular injection on Day 1.	Biological: 24-Valent Pneumococcal Conjugate Vaccine; 0.5 ml dose of VAX-24 will be administered into the deltoid muscle at Day 1
Experimental: VAX-24 Mixed Dose; Participants will receive a single dose of VAX-24 2.2 mcg/4.4 mcg administered as an intramuscular injection on Day 1.	Biological: 24-Valent Pneumococcal Conjugate Vaccine; 0.5 ml dose of VAX-24 will be administered into the deltoid muscle at Day 1
Active Comparator: PCV20; Participants will receive a single intramuscular injection of the standard dose of PCV20 on Day 1.	Biological: Pneumococcal 20-valent Conjugate Vaccine; 0.5 ml dose of Prevnar 20 will be administered into the deltoid muscle at Day 1; Other Names: Prevnar 20, PCV20

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Percentage of Participants Reporting Solicited Local Reactions Within 7 Days After Vaccination	Solicited local reactions included redness/erythema, swelling/induration, and pain at injection site	7 days after vaccination
Percentage of Participants Reporting Solicited Systemic Events Within 7 Days After Vaccination	Solicited systemic reactions include fever, headache, fatigue, muscle pain, and joint pain within 7 days of vaccination	7 days after vaccination
Percentage of Subjects Reporting Unsolicited Adverse Events Within 1 Month After Vaccination	Percentage of participants with at least one Treatment Emergent Adverse Event (unsolicited AEs and SAEs)	1 month after vaccination
Percentage of Participants Reporting SAEs and New Onset of Chronic Illnesses (NOCIs)	Percentage of participants with serious adverse events (SAEs) and new onset of chronic illness (NOCIs)	6 months after vaccination

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
VAX-24 Pneumococcal Serotype-specific Opsonophagocytic Assay (OPA) Geometric Mean Titer (GMTs)	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.	1 month after vaccination
24 VAX-24 Pneumococcal Serotype-specific IgG Geometric Mean Concentration (GMCs)	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.	1 month after vaccination

Collaborators and Investigators

• Sponsor: Vaxcyte, Inc.
• Investigators: Study Director: Clinical Development, Vaxcyte, Inc.

Publications and helpful links

General Publications

• Wassil J, Sisti M, Fairman J, Rankin B, Clark J, Bennett S, Johnson D, Migone TS, Nguyen K, Paschenko A, Sauer P, Iki S, Hanson ME, Simon JK. A phase 2, randomized, blinded, dose-finding, controlled clinical trial to evaluate the safety, tolerability, and immunogenicity of a 24-valent pneumococcal conjugate vaccine (VAX-24) in healthy adults 65 years and older. Vaccine. 2024 Nov 14;42(25):126124. doi: 10.1016/j.vaccine.2024.07.025. Epub 2024 Jul 17.

Study record dates

Study Major Dates

• Study Start (Actual): June 15, 2022
• Primary Completion (Actual): February 15, 2023
• Study Completion (Actual): February 15, 2023

Study Registration Dates

• First Submitted: March 17, 2022
• First Submitted That Met QC Criteria: March 17, 2022
• First Posted (Actual): March 28, 2022

Study Record Updates

• Last Update Posted (Estimated): October 9, 2024
• Last Update Submitted That Met QC Criteria: September 26, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Immunologic Factors; Vaccines; Heptavalent Pneumococcal Conjugate Vaccine
• Other Study ID Numbers: VAX24-102

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Vaxcyte is committed to providing access to anonymized data from the company's clinical trials for the purpose of legitimate scientific research. Requests for data may be addressed to datasharing@vaxcyte.com. Requests must be accompanied by a detailed analysis plan and will be reviewed for scientific validity. Data will be made available after initial product approval. Sharing of data may require execution of a data-sharing agreement.
• IPD Sharing Time Frame: Individual participant data will be shared after deidentification and made available starting 6 months after initial product approval.
• IPD Sharing Access Criteria: Criteria will depend on the specific proposal received and may include qualification of the scientific researchers, potential contribution to the research field, scientific rigor of statistical and analytical methods, and other criteria appropriate for the proposal.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No