NCT07300267 · Merck Sharp & Dohme LLC
A Clinical Study of Novel Pneumococcal Vaccine V118C in Children (V118C-002)
What this study is about
Researchers are looking for new vaccines to prevent pneumococcal disease, which is any infection in the lungs or other parts of the body that is caused by a type of bacteria called Streptococcus pneumoniae. V118C is a new vaccine designed to help prevent disease from Streptococcus pneumoniae bacteria. This study will look at V118C in toddlers and infants.
View original scientific description
Researchers are looking for new vaccines to prevent pneumococcal disease, which is any infection in the lungs or other parts of the body that is caused by a type of bacteria called Streptococcus pneumoniae. V118C is a new vaccine designed to help prevent disease from Streptococcus pneumoniae bacteria. This study will look at V118C in toddlers and infants. The goal of the study is to learn how safe V118C is for children and how well they tolerate it.
Interventions
BIOLOGICAL
V118C (Stage 1)
IM administration of V118C
BIOLOGICAL
V118C (Stage 2)
IM administration of V118C
BIOLOGICAL
PCV20 (Stage 1)
IM administration of PCV20
BIOLOGICAL
PCV20 (Stage 2)
IM administration of PCV20
Primary outcome measures
Stage 1: Percentage of Participants With Immediate Adverse Events (AEs) Following Vaccination
Time frame: Up to approximately 30 minutes postvaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Percentage of participants with immediate AEs following vaccination will be reported.
Stage 1: Percentage of Participants With Solicited Injection-Site Adverse Events (AEs)
Time frame: Up to approximately 7 days postvaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A solicited AE is a predefined event that participants legally acceptable representative (LAR) are specifically asked about and record on their electronic vaccine report card (eVRC). Solicited injection-site AEs include redness, swelling, pain or tenderness and hard lump. Percentage of participants with solicited injection-site AEs will be reported.
Stage 1: Percentage of Participants With Solicited Systemic AEs
Time frame: Up to approximately 7 days postvaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A solicited AE is a predefined event that participants LAR are specifically asked about and record on their eVRC. Solicited systemic AEs include irritability, drowsiness, appetite lost, hives or welts, and fever. Percentage of participants with solicited systemic AEs will be reported.
Stage 1: Percentage of Participants With Unsolicited Systemic or Injection-Site AEs
Time frame: Up to approximately 28 days postvaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An unsolicited AE is an event that is not solicited using a eVRC and that is communicated by a participant. Percentage of participants with unsolicited Systemic or Injection-Site AEs will be reported.
Stage 1: Percentage of Participants With Serious Adverse Events (SAEs)
Time frame: Up to approximately 12 months postvaccination
A serious adverse event (SAE) is an AE that is life-threatening, requires or prolongs an existing hospitalization, results in persistent or significant disability or incapacity, is a congenital anomaly or birth defect, or is another important medical event deemed such by medical or scientific judgment. Percentage of participants with one or more SAEs will be reported.
Stage 1: Percentage of Participants With Medically Attended AEs (MAAEs)
Time frame: Up to approximately 12 months postvaccination
A MAAE is defined as an adverse event in which medical attention is received during an unscheduled, non-routine outpatient visit, such as an emergency department visit, office visit, or an urgent care visit with any medical personnel for any reason. Percentage of participants with MAAEs will be reported.
Stage 2: Percentage of Participants With Immediate AEs Following Vaccination
Time frame: Up to approximately 30 minutes after each vaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. Percentage of participants with immediate AEs following vaccination will be reported.
Stage 2: Percentage of Participants With Solicited Injection-Site AEs
Time frame: Up to approximately 7 days after each vaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A solicited AE is a predefined event that participants LAR are specifically asked about and record on their eVRC. Solicited injection-site AEs include redness, swelling, pain or tenderness and hard lump. Percentage of participants with solicited injection-site AEs will be reported.
Stage 2: Percentage of Participants With Solicited Systemic AEs
Time frame: Up to approximately 7 days after each vaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. A solicited AE is a predefined event that participants LAR are specifically asked about and record on their eVRC. Solicited systemic AEs include irritability, drowsiness, appetite lost, hives or welts, and fever. Percentage of participants with solicited systemic AEs will be recorded.
Stage 2: Percentage of Participants With Unsolicited Systemic or Injection-Site AEs
Time frame: Up to approximately 28 days after each vaccination
An AE is any untoward medical occurrence in a patient or clinical study participant, temporally associated with the use of study intervention, whether or not considered related to the study intervention. An unsolicited AE is an event that is not solicited using a eVRC and that is communicated by a participant. Percentage of participants with unsolicited Systemic or Injection-Site AEs will be reported.
Stage 2: Percentage of Participants With SAEs
Time frame: Up to approximately 12 months postdose 4
A SAE is an AE that is life-threatening, requires or prolongs an existing hospitalization, results in persistent or significant disability or incapacity, is a congenital anomaly or birth defect, or is another important medical event deemed such by medical or scientific judgment. Percentage of participants with one or more SAEs will be reported.
Stage 2: Percentage of Participants With MAAEs
Time frame: Up to approximately 12 months postdose 4
A MAAE is defined as an adverse event in which medical attention is received during an unscheduled, non-routine outpatient visit, such as an emergency department visit, office visit, or an urgent care visit with any medical personnel for any reason. Percentage of participants with MAAEs will be reported.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- The main inclusion criteria include but are not limited to the following: Stage 1:
- Is previously vaccinated with 3 routine infant doses of Pneumococcal 20-valent conjugate vaccine (PCV20)
- Is 12 through 15 months of age Stage 2: \- Is approximately 2 months of age Both Stages:
- Was born at full term (gestational age greater than or equal to 37 weeks)
Exclusion criteria
- The main exclusion criteria include but are not limited to the following: Stage 1: \- Has received a PCV dose at 10 months of age and older Stage 2:
- Has received prior administration of any pneumococcal vaccine Both stages:
- Has a history of invasive pneumococcal disease (IPD)
- Has a known hypersensitivity to any component of V118C or PCV20 including diphtheria toxoid
Where
- Madera, California
- Miami, Florida
- Tampa, Florida
- Topeka, Kansas
- Louisville, Kentucky
- Columbia, Maryland
- St Louis, Missouri
- East Syracuse, New York
- Greenville, South Carolina
- Spartanburg, South Carolina
- Carrollton, Texas
- Garland, Texas
And 2 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Apr 17, 2026 · Source of record for eligibility and locations