Trial Outcomes & Findings for A Phase 2 Study to Learn About a Monovalent Pneumococcal Conjugate Candidate in Healthy Toddlers (NCT NCT06116591)

Results Overview

Local reactions included redness, swelling and pain at injection site. Redness and swelling were graded as mild: \> 0 to 2.0 centimeter (cm), moderate: \>2.0 to 7.0 cm, severe: \>7.0 cm and Grade 4: necrosis or exfoliative dermatitis (redness) and necrosis (swelling). Pain at injection site was graded as mild: hurt if gently touched, moderate: hurt if gently touched, with crying, severe: caused limitation of limb movement and Grade 4 (potentially life threatening): emergency room visit or hospitalization for severe pain at injection site. Grade 4 assessments were made by the investigator. Any local reaction: any mild, moderate, severe, or Grade 4 redness, swelling, or pain at the injection site.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

105 participants

Primary outcome timeframe

Day 1 through Day 7, where Day 1 is the day of Dose 1 administration (Visit 1 of study)

Results posted on

2025-05-08

Participant Flow

Participant milestones

Participant milestones
Measure	mPnC Candidate Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Overall Study STARTED	52	53
Overall Study Dose 1 at Study Visit 1	52	53
Overall Study Dose 2 at Study Visit 3	52	51
Overall Study COMPLETED	52	51
Overall Study NOT COMPLETED	0	2

Reasons for withdrawal

Reasons for withdrawal
Measure	mPnC Candidate Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Overall Study No longer met eligibility criteria	0	1
Overall Study Other: Change in life situation	0	1

Baseline Characteristics

A Phase 2 Study to Learn About a Monovalent Pneumococcal Conjugate Candidate in Healthy Toddlers

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	Total n=105 Participants Total of all reporting groups
Age, Continuous	11.4 Months STANDARD_DEVIATION 0.56 • n=5 Participants	11.3 Months STANDARD_DEVIATION 0.54 • n=7 Participants	11.3 Months STANDARD_DEVIATION 0.55 • n=5 Participants
Sex: Female, Male Female	27 Participants n=5 Participants	25 Participants n=7 Participants	52 Participants n=5 Participants
Sex: Female, Male Male	25 Participants n=5 Participants	28 Participants n=7 Participants	53 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	1 Participants n=5 Participants	2 Participants n=7 Participants	3 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	51 Participants n=5 Participants	51 Participants n=7 Participants	102 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	0 Participants n=5 Participants	1 Participants n=7 Participants	1 Participants n=5 Participants
Race (NIH/OMB) White	52 Participants n=5 Participants	51 Participants n=7 Participants	103 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	0 Participants n=5 Participants	0 Participants n=7 Participants	0 Participants n=5 Participants

PRIMARY outcome

Timeframe: Day 1 through Day 7, where Day 1 is the day of Dose 1 administration (Visit 1 of study)

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 1 and who were evaluable for this outcome measure.

Local reactions included redness, swelling and pain at injection site. Redness and swelling were graded as mild: \> 0 to 2.0 centimeter (cm), moderate: \>2.0 to 7.0 cm, severe: \>7.0 cm and Grade 4: necrosis or exfoliative dermatitis (redness) and necrosis (swelling). Pain at injection site was graded as mild: hurt if gently touched, moderate: hurt if gently touched, with crying, severe: caused limitation of limb movement and Grade 4 (potentially life threatening): emergency room visit or hospitalization for severe pain at injection site. Grade 4 assessments were made by the investigator. Any local reaction: any mild, moderate, severe, or Grade 4 redness, swelling, or pain at the injection site.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Redness: Moderate	0 Percentage of participants Interval 0.0 to 6.8	5.7 Percentage of participants Interval 1.2 to 15.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Redness: Any	17.3 Percentage of participants Interval 8.2 to 30.3	15.1 Percentage of participants Interval 6.7 to 27.6
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Redness: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Redness: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Swelling: Any	15.4 Percentage of participants Interval 6.9 to 28.1	7.5 Percentage of participants Interval 2.1 to 18.2
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Redness: Mild	17.3 Percentage of participants Interval 8.2 to 30.3	9.4 Percentage of participants Interval 3.1 to 20.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Swelling: Mild	11.5 Percentage of participants Interval 4.4 to 23.4	5.7 Percentage of participants Interval 1.2 to 15.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Swelling: Moderate	3.8 Percentage of participants Interval 0.5 to 13.2	1.9 Percentage of participants Interval 0.0 to 10.1
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Swelling: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Swelling: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Pain at the injection site: Any	28.8 Percentage of participants Interval 17.1 to 43.1	30.2 Percentage of participants Interval 18.3 to 44.3
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Pain at the injection site: Mild	21.2 Percentage of participants Interval 11.1 to 34.7	17.0 Percentage of participants Interval 8.1 to 29.8
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Pain at the injection site: Moderate	5.8 Percentage of participants Interval 1.2 to 15.9	13.2 Percentage of participants Interval 5.5 to 25.3
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Pain at the injection site: Severe	1.9 Percentage of participants Interval 0.0 to 10.3	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Local Reactions Within 7 Days After Dose 1 Pain at the injection site: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7

PRIMARY outcome

Timeframe: Day 1 through Day 7, where Day 1 is the day of Dose 2 administration (Visit 3 of study)

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 2 and who were evaluable for this outcome measure.

Local reactions included redness, swelling and pain at injection site. Redness and swelling were graded as mild: \> 0 to 2.0 cm, moderate: \>2.0 to 7.0 cm, severe: \>7.0 cm and Grade 4: necrosis or exfoliative dermatitis (redness) and necrosis (swelling). Pain at injection site was graded as mild: hurt if gently touched, moderate: hurt if gently touched, with crying, severe: caused limitation of limb movement and Grade 4 (potentially life threatening): emergency room visit or hospitalization for severe pain at injection site. Grade 4 assessments were made by the investigator. Any local reaction: any mild, moderate, severe, or Grade 4 redness, swelling, or pain at the injection site.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=51 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Swelling: Mild	0 Percentage of participants Interval 0.0 to 6.8	7.8 Percentage of participants Interval 2.2 to 18.9
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Swelling: Moderate	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Swelling: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Swelling: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Pain at the injection site: Any	15.4 Percentage of participants Interval 6.9 to 28.1	17.6 Percentage of participants Interval 8.4 to 30.9
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Pain at the injection site: Mild	11.5 Percentage of participants Interval 4.4 to 23.4	11.8 Percentage of participants Interval 4.4 to 23.9
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Pain at the injection site: Moderate	3.8 Percentage of participants Interval 0.5 to 13.2	5.9 Percentage of participants Interval 1.2 to 16.2
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Pain at the injection site: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Pain at the injection site: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Redness: Any	13.5 Percentage of participants Interval 5.6 to 25.8	17.6 Percentage of participants Interval 8.4 to 30.9
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Redness: Mild	9.6 Percentage of participants Interval 3.2 to 21.0	15.7 Percentage of participants Interval 7.0 to 28.6
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Redness: Moderate	3.8 Percentage of participants Interval 0.5 to 13.2	2.0 Percentage of participants Interval 0.0 to 10.4
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Redness: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Redness: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Local Reactions Within 7 Days After Dose 2 Swelling: Any	0 Percentage of participants Interval 0.0 to 6.8	7.8 Percentage of participants Interval 2.2 to 18.9

PRIMARY outcome

Timeframe: Day 1 through Day 7, where Day 1 is the day of Dose 1 administration (Visit 1 of study)

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 1 and who were evaluable for this outcome measure.

Fever (oral temperature \>= 38 degree Celsius \[degC\]) was categorized as \>=38.0-38.4 degC, \>38.4-38.9 degC, \>38.9-40.0 degC and \>40.0 degC. Decreased appetite was graded as mild: decreased interest in eating, moderate: decreased oral intake, severe: refusal to feed. Drowsiness was graded as mild: increased/prolonged sleeping bouts, moderate: slightly subdued, interfered daily activity, severe: disabled, not interested in daily activity. Irritability was graded as mild: easily consolable, moderate: required increased attention, severe: inconsolable, crying couldn't be comforted. Grade 4 decreased appetite, drowsiness and irritability events led to emergency room visit or hospitalization and were classified by investigator/medically qualified person. Any systemic event: any fever, decreased appetite, drowsiness, irritability.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Fever: >38.4 deg C to 38.9 deg C	1.9 Percentage of participants Interval 0.0 to 10.3	7.5 Percentage of participants Interval 2.1 to 18.2
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Fever: >38.9 deg C to 40.0 deg C	1.9 Percentage of participants Interval 0.0 to 10.3	1.9 Percentage of participants Interval 0.0 to 10.1
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Fever: >40.0 deg C	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Decreased appetite: Any	40.4 Percentage of participants Interval 27.0 to 54.9	34.0 Percentage of participants Interval 21.5 to 48.3
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Decreased appetite: Mild	17.3 Percentage of participants Interval 8.2 to 30.3	15.1 Percentage of participants Interval 6.7 to 27.6
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Decreased appetite: Moderate	21.2 Percentage of participants Interval 11.1 to 34.7	18.9 Percentage of participants Interval 9.4 to 32.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Fever: >=38.0 deg C	7.7 Percentage of participants Interval 2.1 to 18.5	18.9 Percentage of participants Interval 9.4 to 32.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Fever: >=38.0 deg C to 38.4 deg C	3.8 Percentage of participants Interval 0.5 to 13.2	9.4 Percentage of participants Interval 3.1 to 20.7
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Decreased appetite: Severe	1.9 Percentage of participants Interval 0.0 to 10.3	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Decreased appetite: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Drowsiness: Any	53.8 Percentage of participants Interval 39.5 to 67.8	50.9 Percentage of participants Interval 36.8 to 64.9
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Drowsiness: Mild	42.3 Percentage of participants Interval 28.7 to 56.8	32.1 Percentage of participants Interval 19.9 to 46.3
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Drowsiness: Moderate	9.6 Percentage of participants Interval 3.2 to 21.0	17.0 Percentage of participants Interval 8.1 to 29.8
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Drowsiness: Severe	1.9 Percentage of participants Interval 0.0 to 10.3	1.9 Percentage of participants Interval 0.0 to 10.1
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Drowsiness: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Irritability: Any	73.1 Percentage of participants Interval 59.0 to 84.4	67.9 Percentage of participants Interval 53.7 to 80.1
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Irritability: Mild	23.1 Percentage of participants Interval 12.5 to 36.8	26.4 Percentage of participants Interval 15.3 to 40.3
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Irritability: Moderate	42.3 Percentage of participants Interval 28.7 to 56.8	37.7 Percentage of participants Interval 24.8 to 52.1
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Irritability: Severe	7.7 Percentage of participants Interval 2.1 to 18.5	3.8 Percentage of participants Interval 0.5 to 13.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 1 Irritability: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 6.7

PRIMARY outcome

Timeframe: Day 1 through Day 7, where Day 1 is the day of Dose 2 administration (Visit 3 of study)

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 2 and who were evaluable for this outcome measure.

Fever (oral temperature \>= 38 degC) was categorized as \>=38.0-38.4 degC, \>38.4-38.9 degC, \>38.9-40.0 degC and \>40.0 degC. Decreased appetite was graded as mild: decreased interest in eating, moderate: decreased oral intake, severe: refusal to feed. Drowsiness was graded as mild: increased/prolonged sleeping bouts, moderate: slightly subdued, interfered daily activity, severe: disabled, not interested in daily activity. Irritability was graded as mild: easily consolable, moderate: required increased attention, severe: inconsolable, crying couldn't be comforted. Grade 4 decreased appetite, drowsiness and irritability events led to emergency room visit or hospitalization and were classified by investigator/medically qualified person. Any systemic event: any fever, decreased appetite, drowsiness, irritability.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=51 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Drowsiness: Moderate	11.5 Percentage of participants Interval 4.4 to 23.4	5.9 Percentage of participants Interval 1.2 to 16.2
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Drowsiness: Severe	1.9 Percentage of participants Interval 0.0 to 10.3	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Drowsiness: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Irritability: Any	53.8 Percentage of participants Interval 39.5 to 67.8	49.0 Percentage of participants Interval 34.8 to 63.4
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Irritability: Mild	21.2 Percentage of participants Interval 11.1 to 34.7	19.6 Percentage of participants Interval 9.8 to 33.1
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Irritability: Moderate	30.8 Percentage of participants Interval 18.7 to 45.1	29.4 Percentage of participants Interval 17.5 to 43.8
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Irritability: Severe	1.9 Percentage of participants Interval 0.0 to 10.3	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Irritability: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Fever: >=38.0 deg C	13.5 Percentage of participants Interval 5.6 to 25.8	15.7 Percentage of participants Interval 7.0 to 28.6
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Fever: >=38.0 deg C to 38.4 deg C	9.6 Percentage of participants Interval 3.2 to 21.0	7.8 Percentage of participants Interval 2.2 to 18.9
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Fever: >38.4 deg C to 38.9 deg C	1.9 Percentage of participants Interval 0.0 to 10.3	2.0 Percentage of participants Interval 0.0 to 10.4
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Fever: >38.9 deg C to 40.0 deg C	1.9 Percentage of participants Interval 0.0 to 10.3	5.9 Percentage of participants Interval 1.2 to 16.2
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Fever: >40.0 deg C	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Decreased appetite: Any	23.1 Percentage of participants Interval 12.5 to 36.8	31.4 Percentage of participants Interval 19.1 to 45.9
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Decreased appetite: Mild	7.7 Percentage of participants Interval 2.1 to 18.5	7.8 Percentage of participants Interval 2.2 to 18.9
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Decreased appetite: Moderate	15.4 Percentage of participants Interval 6.9 to 28.1	23.5 Percentage of participants Interval 12.8 to 37.5
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Decreased appetite: Severe	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Decreased appetite: Grade 4	0 Percentage of participants Interval 0.0 to 6.8	0 Percentage of participants Interval 0.0 to 7.0
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Drowsiness: Any	30.8 Percentage of participants Interval 18.7 to 45.1	31.4 Percentage of participants Interval 19.1 to 45.9
Percentage of Participants With Systemic Events Within 7 Days After Dose 2 Drowsiness: Mild	17.3 Percentage of participants Interval 8.2 to 30.3	25.5 Percentage of participants Interval 14.3 to 39.6

PRIMARY outcome

Timeframe: From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months]

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 1 and who were evaluable for this outcome measure.

An AE was any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. Results excluded local reactions and systemic events data.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Adverse Events (AEs) From Dose 1 Through 1 Month After Dose 2	84.6 Percentage of participants Interval 71.9 to 93.1	75.5 Percentage of participants Interval 61.7 to 86.2

PRIMARY outcome

Timeframe: From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months]

Population: Safety analysis set included all participants who received at least 1 dose of the study intervention. Here, ''Overall Number of Participants Analyzed'' signifies participants who received Dose 1 and who were evaluable for this outcome measure.

An AE was any untoward medical occurrence in a participant temporally associated with the use of study intervention, whether or not considered related to the study intervention. An SAE was an AE that resulted in death, was life-threatening, required inpatient hospitalization or prolongation of existing hospitalization, resulted in persistent disability/incapacity; constituted a congenital anomaly/birth defect; was a suspected transmission via a Pfizer product of an infectious agent, pathogenic or nonpathogenic; other situations as judged by investigator.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=52 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Serious Adverse Events (SAEs) From Dose 1 Through 1 Month After Dose 2	1.9 Percentage of participants Interval 0.0 to 10.3	1.9 Percentage of participants Interval 0.0 to 10.1

SECONDARY outcome

Timeframe: 1 month after Dose 1

Population: Dose 1 evaluable immunogenicity population included all participants who were eligible and randomized, received the study intervention to which they were randomized, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 1, and had no other major protocol deviations as determined by the clinician up to the 1-month post-Dose 1 visit.

GMCs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the concentrations and the corresponding CIs (based on the student t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=50 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=49 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Geometric Mean Concentration (GMCs) of Pneumococcal Immunoglobulin G (IgG) at 1 Month After Dose 1	7.53 Microgram/milliliter (mcg/mL) Interval 5.68 to 9.99	5.73 Microgram/milliliter (mcg/mL) Interval 4.51 to 7.29

SECONDARY outcome

Timeframe: 1 month after Dose 2

Population: Dose 2 evaluable immunogenicity population included all participants who were eligible and randomized, received both doses of study intervention to which they were randomly assigned, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 2, and had no other major protocol deviations as determined by the clinician up to the 1-month post-Dose 2 visit.

GMCs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of the concentrations and the corresponding CIs (based on the student t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=50 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=48 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
GMCs of Pneumococcal IgG at 1 Month After Dose 2	17.41 Microgram/milliliter (mcg/mL) Interval 13.9 to 21.79	8.08 Microgram/milliliter (mcg/mL) Interval 6.42 to 10.16

SECONDARY outcome

Timeframe: 1 month after Dose 1

Population: Dose 1 evaluable immunogenicity population included all participants who were eligible and randomized, received the study intervention to which they were randomized, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 1, and had no other major protocol deviations as determined by the clinician up to the 1-month post-Dose 1 visit.

Predefined IgG concentrations was \>= 0.35 micrograms per milliliter (mcg/mL).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=50 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=49 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Predefined IgG Concentrations at 1 Month After Dose 1	98.0 Percentage of participants Interval 89.4 to 99.9	100.0 Percentage of participants Interval 92.7 to 100.0

SECONDARY outcome

Timeframe: 1 month after Dose 2

Population: Dose 2 evaluable immunogenicity population included all participants who were eligible and randomized, received both doses of study intervention to which they were randomly assigned, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 2, and had no other major protocol deviations as determined by the clinician up to the 1-month post-Dose 2 visit.

Predefined level of IgG concentrations was \>= 0.35 mcg/mL.

Outcome measures

Outcome measures
Measure	mPnC Candidate n=50 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=48 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Percentage of Participants With Predefined IgG Concentrations at 1 Month After Dose 2	100.0 Percentage of participants Interval 92.9 to 100.0	100.0 Percentage of participants Interval 92.6 to 100.0

SECONDARY outcome

Timeframe: From before Dose 1 to 1 month after Dose 1

Population: Dose 1 evaluable immunogenicity population included all participants who were eligible and randomized, received study intervention to which they were randomized, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 1, and had no other major protocol deviations as determined by clinician up to 1-month post-Dose 1 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 1 evaluable participants with valid result at both timepoints.

GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the student-t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=46 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=46 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Geometric Mean Fold Rise (GMFRs) of Pneumococcal IgG From Before Dose 1 to 1 Month After Dose 1	496.7 Fold rise Interval 316.2 to 780.3	306.3 Fold rise Interval 196.7 to 476.9

SECONDARY outcome

Timeframe: From 1 month after Dose 1 to 1 month after Dose 2

Population: Dose 2 evaluable immunogenicity population included all participants who were eligible, randomized, received both doses of study intervention to which they were randomly assigned, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 2, had no major protocol deviations as determined by clinician up to 1-month post-Dose 2 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 2 evaluable participants with valid result at both timepoints.

GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the student-t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=48 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=45 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
GMFRs of Pneumococcal IgG From 1 Month After Dose 1 to 1 Month After Dose 2	2.4 Fold rise Interval 1.9 to 2.9	1.5 Fold rise Interval 1.3 to 1.7

SECONDARY outcome

Timeframe: 1 month after Dose 1

Population: Dose 1 evaluable immunogenicity population included all participants who were eligible and randomized, received study intervention to which they were randomized, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 1, and had no other major protocol deviations as determined by clinician up to 1-month post-Dose 1 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 1 evaluable participants with valid OPA titers.

GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on student's t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=49 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=48 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Geometric Mean Titer (GMTs) of Pneumococcal Opsonophagocytic Activity (OPA) at 1 Month After Dose 1	425 Titer Interval 346.0 to 522.0	447 Titer Interval 363.0 to 550.0

SECONDARY outcome

Timeframe: 1 month after Dose 2

Population: Dose 2 evaluable immunogenicity population included all participants who were eligible, randomized, received both doses of study intervention to which they were randomly assigned, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 2, had no major protocol deviations as determined by clinician up to 1-month post-Dose 2 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 2 evaluable participants with valid OPA titers.

GMTs and the corresponding 2-sided CIs were calculated by exponentiating the mean logarithm of the titers and the corresponding CIs (based on student's t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=50 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=47 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
GMTs of Pneumococcal OPA at 1 Month After Dose 2	645 Titer Interval 538.0 to 773.0	544 Titer Interval 455.0 to 650.0

SECONDARY outcome

Timeframe: From before Dose 1 to 1 month after Dose 1

Population: Dose 1 evaluable immunogenicity population included all participants who were eligible and randomized, received study intervention to which they were randomized, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 1, and had no other major protocol deviations as determined by clinician up to 1-month post-Dose 1 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 1 evaluable participants with valid OPA result at both timepoints.

GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the student-t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=44 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=45 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
GMFRs of Pneumococcal OPA From Before Dose 1 to 1 Month After Dose 1	40.7 Fold rise Interval 30.4 to 54.6	42.6 Fold rise Interval 30.3 to 59.9

SECONDARY outcome

Timeframe: From 1 month after Dose 1 to 1 month after Dose 2

Population: Dose 2 evaluable immunogenicity population included all participants who were eligible, randomized, received both doses of study intervention to which they were randomly assigned, had at least 1 valid immunogenicity result within 27 to 56 days, inclusive, after Dose 2, had no major protocol deviations as determined by clinician up to 1-month post-Dose 2 visit. Here, ''Overall Number of Participants Analyzed'' signifies Dose 2 evaluable participants with valid OPA result at both timepoints.

GMFRs and 2-sided 95% CIs were calculated by exponentiating the mean logarithm of fold rises and the corresponding CIs (based on the student-t distribution).

Outcome measures

Outcome measures
Measure	mPnC Candidate n=47 Participants Participants who had previously received 2 doses of 10-valent pneumococcal conjugate vaccine (PCV10) primary series as part of their infant routine vaccines were administered 0.5 milliliter (mL) dose of monovalent pneumococcal conjugate (mPnC) candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=43 Participants Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
GMFRs of Pneumococcal OPA From 1 Month After Dose 1 to 1 Month After Dose 2	1.5 Fold rise Interval 1.2 to 1.9	1.3 Fold rise Interval 1.1 to 1.5

Adverse Events

mPnC Candidate

Serious events: 1 serious events

Other events: 51 other events

Deaths: 0 deaths

mPnC Control

Serious events: 1 serious events

Other events: 53 other events

Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure	mPnC Candidate n=52 participants at risk Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 participants at risk Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
Infections and infestations Bronchitis	0.00% 0/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	1.9% 1/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Cytomegalovirus infection	1.9% 1/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	0.00% 0/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.

Other adverse events

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
Publication restrictions are in place

Restriction type: OTHER

Measure	mPnC Candidate n=52 participants at risk Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC candidate intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.	mPnC Control n=53 participants at risk Participants who had previously received 2 doses of PCV10 primary series as part of their infant routine vaccines were administered 0.5 mL dose of mPnC control intramuscularly at Visit 1 of the study (Day 1 of study; Dose 1) and Visit 3 of the study (56 to 70 days after Visit 1; Dose 2). Participants also received their third (toddler) dose of PCV10 at Visit 1 per childhood vaccine standard of care.
General disorders Pyrexia	5.8% 3/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	1.9% 1/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Gastrointestinal disorders Diarrhoea	13.5% 7/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	3.8% 2/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Gastroenteritis	26.9% 14/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	22.6% 12/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Nasopharyngitis	15.4% 8/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	9.4% 5/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Otitis media	9.6% 5/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	7.5% 4/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Rhinitis	7.7% 4/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	5.7% 3/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Infections and infestations Upper respiratory tract infection	46.2% 24/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	41.5% 22/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
General disorders Injection site erythema (REDNESS)	25.0% 13/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	28.3% 15/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
General disorders Injection site pain (PAIN)	30.8% 16/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	35.8% 19/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
General disorders Injection site swelling (SWELLING)	15.4% 8/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	11.3% 6/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
General disorders Pyrexia (FEVER)	15.4% 8/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	28.3% 15/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Metabolism and nutrition disorders Decreased appetite (DECREASED APPETITE)	50.0% 26/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	47.2% 25/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Nervous system disorders Hypersomnia (INCREASED SLEEP)	59.6% 31/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	62.3% 33/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Psychiatric disorders Irritability (IRRITABILITY)	80.8% 42/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	81.1% 43/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.
Gastrointestinal disorders Vomiting	5.8% 3/52 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.	0.00% 0/53 • Local reactions and systemic events (systematic collection): Within 7 days after Dose 1 and Dose 2; AEs, SAEs and all-cause mortality (non-systematic collection): From Dose 1 through 1 month after Dose 2 [up to approximately 3.7 months] Same event may appear as both an AE and SAE. However, what is presented are distinct events. An event may be categorized as serious in one participant and as non-serious in another, or a participant may have experienced both a serious and non-serious event. Safety analysis set included all participants who received at least 1 dose of study intervention.