Last updated: 09/17/2026 12:30:50
A Phase 2 Study to Evaluate the Safety, Tolerability, and Immune response of AFX3772 Vaccine in Healthy Infants
EudraCT ID
EU CT Number
Not applicable
Trial status
Completed
Completed
Trial overview
Official title: A Phase 2, Randomized, Double-blind, Multi-dose, Dose Finding Study to Evaluate the Safety, Tolerability and Immunogenicity of AFX3772 Compared With PCVs in Healthy Infants
Trial description: This is a Phase 2 clinical study evaluating AFX3772 in healthy infants for the prevention of pneumococcal disease. The purpose of this study is to determine the safety, tolerability, and immunogenicity of three different formulations of AFX3772 compared with Prevnar 13 (PCV13) and Prevnar 20 (PCV20).Part 1 is the dose-escalation lead-in portion of the study, in which infants at each dose level are randomized 3:1 in sequential cohorts to receive increasing doses of AFX3772 or PCV13.In Part 2, infants are randomized to receive either one of two dose levels of AFX3772 or PCV20.On 31 October 2024, the study was placed on partial clinical hold by the U.S. Food and Drug Administration. The hold was not related to safety concerns in participants who had already received the study vaccines. As a result, enrollment was paused and no further doses of the investigational pneumococcal vaccine were administered. Participants who were already enrolled transitioned to the standard of care pneumococcal vaccine to complete their scheduled visits through post-dose 3 and subsequently completed study follow-up.
Primary purpose:
Prevention
Trial design:
Sequential Assignment
Masking:
Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Allocation:
Randomized
Primary outcomes:
Number of participants reporting any solicited injection site adverse events (AEs) after first dose
Timeframe: Day 1 to Day 7 post dose 1
Number of participants reporting any solicited injection site AEs after second dose
Timeframe: Day 1 to Day 7 post dose 2
Number of participants reporting any solicited injection site AEs after third dose
Timeframe: Day 1 to Day 7 post dose 3
Number of participants reporting any solicited systemic events after first dose
Timeframe: Day 1 to Day 7 post dose 1
Number of participants reporting any solicited systemic events after second dose
Timeframe: Day 1 to Day 7 post dose 2
Number of participants reporting any solicited systemic events after third dose
Timeframe: Day 1 to Day 7 post dose 3
Number of participants reporting any unsolicited AEs
Timeframe: Within 30 days post each dose (at 2, 4, and 6 months of age as part of primary vaccination series)
Number of participants reporting any serious adverse events (SAEs)
Timeframe: Day 1 through 6 months post dose 3
Secondary outcomes:
Proportion of participants with a pneumococcal serotype-specific Immunoglobulin G (IgG) concentration of >= 0.35 μg/mL
Timeframe: 30 days post-dose 2 and 3
Geometric Mean Concentration (GMC) for serotype-specific IgG
Timeframe: 30 days post-dose 2 and 3
Interventions:
Biological/vaccine: AFX3772
Biological/vaccine: Prevnar 13
Biological/vaccine: Prevnar 20
Enrollment:
388
Primary completion date:
2025-18-09
Observational study model:
Not applicable
Time perspective:
Not applicable
Clinical publications:
Not applicable
Medical condition
Pneumonia, Bacterial, Pneumonia, Pneumococcal
Product
Not applicable
Collaborators
Not applicable
Study date(s)
June 2022 to September 2025
Type
Interventional
Phase
2
Participation criteria
Sex
Female & Male
Age
42 - 90 Days
Accepts healthy volunteers
Yes
- 1. Participant has an LAR who understands study procedures, alternative treatments and risks involved in the study and who voluntarily agrees to participate by giving informed consent.
- 2. Participant is a full-term (≥37 weeks gestation at birth) infant approximately 2 months of age (42 to 90 days, inclusive) at time of obtaining the informed consent.
- 1. Participant had prior administration of any pneumococcal vaccine.
- 2. Participant has a known or suspected hypersensitivity to AFX3772, PCV13, PCV20 or any components of the formulations used.
Inclusion and exclusion criteria
Inclusion criteria:
- 1. Participant has an LAR who understands study procedures, alternative treatments and risks involved in the study and who voluntarily agrees to participate by giving informed consent. 2. Participant is a full-term (≥37 weeks gestation at birth) infant approximately 2 months of age (42 to 90 days, inclusive) at time of obtaining the informed consent. 3. Participant is healthy based on the clinical judgment of the investigator following review of medical history and physical examination.
Exclusion criteria:
- 1. Participant had prior administration of any pneumococcal vaccine. 2. Participant has a known or suspected hypersensitivity to AFX3772, PCV13, PCV20 or any components of the formulations used. 3. Participant has a known or suspected immunodeficiency (including autoimmune disease) or other conditions associated with immunosuppression that may require immunosuppressive drugs including but not limited to HIV infection, malignancy or organ or bone marrow transplant. a. In addition, the participant’s biological mother has known HIV infection or known to be hepatitis B surface antigen positive. 4. Participant has any clinically significant allergic condition or history (including anaphylactic reactions, but excluding untreated, asymptomatic, seasonal allergies) prior to the first vaccination for primary immunization series. 5. Participant has functional asplenia. 6. Participant has medical history of epilepsy or febrile convulsion. 7. Participant weighed <2000 g at birth. 8. Participant has known neurological or cognitive behavioral disorders including clinically significant developmental disorder and related disorders. 9. Participant has any active malignancy or history of malignancy. 10. Participant has a history of microbiologically proven invasive disease caused by S. pneumoniae. 11. Participant has cochlear implant or cerebrospinal fluid leakage. 12. Has received other licensed non-live vaccines within the 14 days or a licensed live virus vaccine within the 30 days prior to receipt of study vaccine. 13. Participant has received immunoglobulins. Note: This does not include monoclonal antibodies, such as palivizumab or nirsevimab. 14. Participant has a bleeding diathesis or condition associated with prolonged bleeding that would contraindicate intramuscular injection. 15. Participant has received systemic corticosteroids (equivalent of >2 mg/kg total daily dose of prednisone or >20 mg/day for persons weighing >10 kg) for a period of more than 14 days and has not completed the treatment for at least 30 days before study vaccine. Topical, ophthalmic, and inhaled steroids are allowed. 16. Participant has febrile illness (rectal temperature ≥38.1°C [100.5°F] or axillary temperature ≥37.8°C [100.0°F]) in Part 1 and Part 2 prior to the effective date of protocol amendment 4. After protocol amendment 4 becomes effective, febrile illness is defined as rectal temperature ≥38.0°C [100.4°F] or axillary temperature ≥37.5°C (99.1°F) in Part 2. Upon resolution of symptoms, participant can be rescreened. 17. Participant has received any investigational therapy within 28 days or 5 half-lives, whichever is longer, prior to screening. 18. Participant has any condition which, in the investigator’s opinion, makes the participant unsuitable for study participation. 19. LARs that are study personnel or their immediate dependents, family, or household members.
Trial location(s)
Location
GSK Investigational Site
Jefferson Hills, PA, United States, 15025
Status
Study Complete
Location
GSK Investigational Site
Houston, TX, United States, 77087-1122
Status
Study Complete
Location
GSK Investigational Site
Salt Lake City, UT, United States, 84107
Status
Study Complete
Location
GSK Investigational Site
Syracuse, UT, United States, 84075-9645
Status
Study Complete
Location
GSK Investigational Site
South Jordan, UT, United States, 84095-3211
Status
Study Complete
Location
GSK Investigational Site
St Augustine, FL, United States, 32086-5774
Status
Study Complete
Location
GSK Investigational Site
Norfolk, NE, United States, 68701-7701
Status
Study Complete
Location
GSK Investigational Site
New Orleans, LA, United States, 70119-7100
Status
Study Complete
Location
GSK Investigational Site
Bayamon, Puerto Rico, United States, 960
Status
Study Complete
Location
GSK Investigational Site
Pittsburgh, PA, United States, 15213-3205
Status
Study Complete
Location
GSK Investigational Site
Caguas, Puerto Rico, United States, 00725
Status
Study Complete
Location
GSK Investigational Site
Charleston, SC, United States, 29407-4726
Status
Study Complete
Location
GSK Investigational Site
Covington, Louisiana, United States, 70433
Status
Study Complete
Location
GSK Investigational Site
Pittsburgh, Pennsylvania, United States, 15234
Status
Study Complete
Location
GSK Investigational Site
North Huntingdon, Pennsylvania, United States, 15642
Status
Study Complete
Location
GSK Investigational Site
Cranberry Township, PA, United States, 16006
Status
Study Complete
Study documents
Protocol
Available language(s): English
Statistical analysis plan
Available language(s): English
If you wish to request for full study report, please contact - [email protected]
Results overview
Results posted on ClinicalTrials.gov
Recruitment status
Completed
Actual primary completion date
2025-18-09
Actual study completion date
2025-18-09
Plain language summaries
Summary of results in plain language
Available language(s): English, Spanish (United States)
Additional information about the trial
Additional information
Not applicable
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