Trial Outcomes & Findings for Booster Dose Trial (NCT NCT05016622)

NCT ID: NCT05016622

Last Updated: 2024-07-31

Results Overview

Rate will be determined as the percentage of patients demonstrating booster-induced seroconversion, as evidenced by anti-Spike antibody testing, who were seronegative after the primary series of FDA authorized COVID-19 vaccinations.

• Recruitment status: TERMINATED
• Study phase: PHASE2
• Target enrollment: 106 participants
• Primary outcome timeframe: 4 weeks after administration of 1st booster dose
• Results posted on: 2024-07-31

Participant Flow

189 patients were assessed for eligibility to receive a booster COVID-19 vaccine after at least 28 days following completion of the standard COVID-19 vaccination series. Of the 189 patients, 56 patients declined to participate in the study, 2 patients did not meet eligibility criteria, and 25 participants were not enrolled due to 'Other reasons.' Accordingly, 106 patients were enrolled into the Booster Dose Trial.

Participant milestones

Measure	Booster Dose 1. 1st Booster Dose: Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated. 2. 2nd Booster Dose: For patients who failed to seroconvert after their third/booster dose of vaccine or had low antibody responses (\<1000 AU/mL anti-S antibody as determined by assay measured at least 14 days after the third dose) a fourth dose of either mRNA or adenoviral vaccine was administered. Responses were assessed at 4 weeks after the fourth dose to assess anti-S antibody results. Following implementation of the protocol, the Centers for Disease Control and Prevention (CDC) published a statement that advised that the mRNA vaccines should be administered preferentially over the adenoviral (Ad26.CoV2.S) vaccines.
1st Booster: 4 Week Follow up Visit STARTED	106
1st Booster: 4 Week Follow up Visit COMPLETED	106
1st Booster: 4 Week Follow up Visit NOT COMPLETED	0
1st Booster: 4-6 Month Follow up Visit STARTED	106
1st Booster: 4-6 Month Follow up Visit COMPLETED	47
1st Booster: 4-6 Month Follow up Visit NOT COMPLETED	59
2nd Booster: 4 Week Follow up Visit STARTED	20
2nd Booster: 4 Week Follow up Visit COMPLETED	18
2nd Booster: 4 Week Follow up Visit NOT COMPLETED	2
2nd Booster: 4-6 Month Follow up Visit STARTED	18
2nd Booster: 4-6 Month Follow up Visit COMPLETED	0
2nd Booster: 4-6 Month Follow up Visit NOT COMPLETED	18

Reasons for withdrawal

Measure	Booster Dose 1. 1st Booster Dose: Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated. 2. 2nd Booster Dose: For patients who failed to seroconvert after their third/booster dose of vaccine or had low antibody responses (\<1000 AU/mL anti-S antibody as determined by assay measured at least 14 days after the third dose) a fourth dose of either mRNA or adenoviral vaccine was administered. Responses were assessed at 4 weeks after the fourth dose to assess anti-S antibody results. Following implementation of the protocol, the Centers for Disease Control and Prevention (CDC) published a statement that advised that the mRNA vaccines should be administered preferentially over the adenoviral (Ad26.CoV2.S) vaccines.
1st Booster: 4-6 Month Follow up Visit Lost to Follow-up	59
2nd Booster: 4 Week Follow up Visit Declined to Participate	2

Baseline Characteristics

At baseline (i.e. after primary vaccination) 88 patients had evaluable T-cell results

Baseline characteristics by cohort

Measure	All Study Participants n=106 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 4-6 months after their third/booster dose
Age, Continuous	68 years n=106 Participants
Sex: Female, Male Female	58 Participants n=106 Participants
Sex: Female, Male Male	48 Participants n=106 Participants
Race/Ethnicity, Customized Caucasian	36 Participants n=106 Participants
Race/Ethnicity, Customized African-American	33 Participants n=106 Participants
Race/Ethnicity, Customized Hispanic	27 Participants n=106 Participants
Race/Ethnicity, Customized Asian	9 Participants n=106 Participants
Race/Ethnicity, Customized Other	1 Participants n=106 Participants
Region of Enrollment United States	106 participants n=106 Participants
Previous Vaccine Administered BNT162b2	72 Participants n=106 Participants
Previous Vaccine Administered mRNA-1273	28 Participants n=106 Participants
Previous Vaccine Administered Ad26.CoV2.S	6 Participants n=106 Participants
Type of Booster Vaccine BNT162b2	78 Participants n=106 Participants
Type of Booster Vaccine mRNA-1273	28 Participants n=106 Participants
Malignancy Category Hematologic Malignancy	66 Participants n=106 Participants
Malignancy Category Solid Tumor Malignancy	40 Participants n=106 Participants
Hematologic Malignancy Lymphoid	55 Participants n=106 Participants
Hematologic Malignancy Myeloid	11 Participants n=106 Participants
Cancer Status Active	69 Participants n=106 Participants
Cancer Status Progressive	3 Participants n=106 Participants
Cancer Status Recurrent	3 Participants n=106 Participants
Cancer Status Relapse	7 Participants n=106 Participants
Cancer Status Remission	24 Participants n=106 Participants
On Treatment at the Time of Booster Yes	80 Participants n=106 Participants
On Treatment at the Time of Booster No	26 Participants n=106 Participants
Median Titer after Primary Vaccination Series	212.1 AU/mL n=106 Participants
Positive Anti-spike IgG Titers among Patients with evaluable T-cell Results	65 Participants n=88 Participants • At baseline (i.e. after primary vaccination) 88 patients had evaluable T-cell results
Patients with evaluable positive T-cell immune responses who were seronegative for Anti-S antibody	21 Participants n=65 Participants • 65 patients with evaluable T-cell immune responses demonstrated a positive T-cell response against SARS-CoV-2
Percentage of Patients Seropositive/Seronegative at Baseline (before 1st booster dose) Seropositive Patients	68 Participants n=106 Participants • Percentage of patients seronegative at baseline following the standard 2 dose vaccination series as demonstrated by anti-S antibody testing. Biobanked samples were available for 103 patients.
Percentage of Patients Seropositive/Seronegative at Baseline (before 1st booster dose) Seronegative Patients	35 Participants n=106 Participants • Percentage of patients seronegative at baseline following the standard 2 dose vaccination series as demonstrated by anti-S antibody testing. Biobanked samples were available for 103 patients.
Patients with neutralizing antibodies (in seropositive patients)	47 Participants n=68 Participants • 68 patients were seropositive at baseline following primary COVID-19 vaccination series. The GenScript surrogate virus neutralization assay was used to analyze samples for neutralizing antibodies.

PRIMARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 35 of 106 patients were seronegative after initial 2 dose vaccination series. At 4 weeks following receipt of the booster vaccine, 57% (20/35) of these patients seroconverted and had a detectable antibody response as demonstrated by anti-S antibody testing

Rate will be determined as the percentage of patients demonstrating booster-induced seroconversion, as evidenced by anti-Spike antibody testing, who were seronegative after the primary series of FDA authorized COVID-19 vaccinations.

Outcome measures

Measure

1st Booster Dose n=35 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Rate of Seroconversion for SARS-CoV-2 Spike Antibody Among Patients Who Were Seronegative After Primary Series of COVID-19 Vaccinations

20 Participants

PRIMARY outcome

Timeframe: 4 weeks after administration of 2nd booster dose

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

A patient was classified as a responder if they either (1) had positive anti-S antibody at 4 weeks if seronegative at baseline (following 1st booster dose) or (2) if they achieved a titer of >1000 AU/mL at 4 weeks if they were sero-low at baseline (following 1st booster dose)

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients Who Were 'Responders' After 2nd Booster Dose

12 Participants

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 89 patients had evaluable T-cell results at 4 weeks following 1st booster dose of vaccine

The number of patients with evaluable T-cell immune responses who demonstrated positive anti-S antibody (IgG) titers against SARS-CoV-2 after 1st booster dose of vaccine.

Outcome measures

Measure

1st Booster Dose n=89 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Positive Anti-Spike Antibody (IgG) Titer

76 Participants

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

The median SARS-CoV-2 spike antibody (IgG) titer among the entire cohort at 4 weeks after administration of the 1st booster dose of vaccine was determined.

Outcome measures

Measure

1st Booster Dose n=106 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Spike Antibody Titer

9997 AU/mL Interval 880.7 to 47063.0

SECONDARY outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 66 patients had Hematologic malignancies

The median change in anti-S antibody titer for patients with Hematologic malignancies was determined.

Outcome measures

Measure

1st Booster Dose n=66 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Change in Anti-Spike Antibody Titer for Patients With Hematologic Malignancies

2167 AU/mL Interval 0.0 to 10131.0

SECONDARY outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 40 patients had Solid Tumor malignancies

The median change in anti-S antibody titer for patients with Solid tumor malignancies was determined.

Outcome measures

Measure

1st Booster Dose n=40 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Change in Anti-Spike Antibody Titer for Patients With Solid Tumor Malignancies

31010 AU/mL Interval 9531.0 to 44464.0

SECONDARY outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: Of patients with Hematologic malignancies, 55 patients had Lymphoid malignancies and 11 patients had Myeloid malignancies

Median change in Anti-S antibody titers was determined in patients who presented with Hematologic (either Lymphoid or Myeloid) malignancies.

Outcome measures

Measure	1st Booster Dose n=66 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Change in Anti-Spike Antibody Titer Among Patients With Hematologic Malignancy by Type Lymphoid Malignancies	1169 AU/mL Interval 0.0 to 8661.0
Change in Anti-Spike Antibody Titer Among Patients With Hematologic Malignancy by Type Myeloid Malignancies	9424 AU/mL Interval 4381.0 to 20444.0

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 4 week samples were not collected/processed from 6 patients

Percentage of Patients who were either seropositive or seronegative following administration of 1st booster dose as demonstrated by anti-S antibody testing.

Outcome measures

Measure	1st Booster Dose n=100 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Percentage of Patients Seropositive/Seronegative Following 1st Booster Dose Seropositive Patients	85 Participants
Percentage of Patients Seropositive/Seronegative Following 1st Booster Dose Seronegative Patients	15 Participants

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 85 patients were seropositive at 4 weeks.

The GenScript surrogate virus neutralization assay was used to analyze samples from seropositive patients to detect for the presence of neutralizing antibodies. The percentage of patients with neutralizing antibodies was determined.

Outcome measures

Measure

1st Booster Dose n=85 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Neutralizing Antibodies Detected Among Seropositive Patients

77 Participants

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 15 patients had a negative anti-S antibody result at 4 weeks following booster dose administration.

Percentage of patients with a negative anti-S antibody following 1st booster dose who demonstrated a Positive T-cell response.

Outcome measures

Measure

1st Booster Dose n=15 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Positive T-cell Response Among Patients With a Negative Anti-S Antibody

11 Participants

SECONDARY outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 21 patients demonstrated a negative T-cell response against SARS-CoV-2 at baseline

Percentage of patients who demonstrated a Positive T-cell response among those who demonstrated a negative T-cell response at baseline.

Outcome measures

Measure

1st Booster Dose n=21 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Positive T-cell Response Among Patients With a Negative T-cell Response at Baseline

14 Participants

SECONDARY outcome

Timeframe: Within 6 months prior to treatment to 4 weeks after administration of 1st booster dose

Population: 25 patients were on Anti-CD20 antibody therapy within 6 months of treatment

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were assessed for patients on anti-CD20 antibody therapy within 6 months of administration of 1st booster dose.

Outcome measures

Measure

1st Booster Dose n=25 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients on Anti-CD20 Antibody Therapy Within 6 Months of Treatment

0 AU/mL Interval 0.0 to 0.0

SECONDARY outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 25 patients were on Anti-CD20 antibody therapy just prior to the study

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were assessed for patients on anti-CD20 antibody therapy just prior to the study.

Outcome measures

Measure

1st Booster Dose n=25 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients on Anti-CD20 Antibody Therapy

0 AU/mL Interval 0.0 to 910.5

SECONDARY outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 81 patients were not on Anti-CD20 antibody therapy just prior to the study

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were assessed for patients not on anti-CD20 antibody therapy just prior to the study.

Outcome measures

Measure

1st Booster Dose n=81 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients Not on Anti-CD20 Antibody Therapy

12735 AU/mL Interval 2842.0 to 38863.0

SECONDARY outcome

Timeframe: Within 6 months prior to treatment to 4 weeks after administration of 1st booster dose

Population: 81 patients were not on Anti-CD20 antibody therapy within 6 months prior to treatment

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were assessed for patients not on anti-CD20 antibody therapy within 6 months of treatment

Outcome measures

Measure

1st Booster Dose n=81 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients Not on Anti-CD20 Antibody Therapy Within 6 Months of Treatment

587 AU/mL Interval 0.0 to 4314.0

SECONDARY outcome

Timeframe: ~4-6 months after administration of 1st booster dose

Population: 47 patients completed their 4-6 month follow-up visit following 1st booster dose. All 47 were seropositive at 4 weeks. 36 of these patients had hematologic malignancies and 11 of these patients had solid malignancies. Six patients had received anti-COVID monoclonal antibody therapy as per standard of care between the 4 week and 4-6 months' follow-up period. Nine patients had received a fourth dose of COVID-19 vaccine outside of the context of the study prior to the time of 4-6 months' follow-up.

Percentage of Patients who maintained a positive anti-S antibody (seropositive) following administration of 1st booster dose as demonstrated by anti-S antibody testing.

Outcome measures

Measure

1st Booster Dose n=47 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients Who Remained Seropositive Following 1st Booster Dose

47 Participants

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 18 participants were enrolled into the second booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The percentage of patients determined to be seronegative before 2nd booster dose

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Seronegative Patients Before 2nd Booster Dose

7 Participants

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 18 participants were enrolled into the second booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The percentage of patients with low serum antibodies before administration of the 2nd booster dose was determined by assay. Patients with anti-S antibody titers of <1000 AU/mL were determined to have low serum antibodies.

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients With Low (Anti-S Antibody) Serum Antibodies

11 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 18 participants were enrolled into the second booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The percentage of patients who were classified as 'responders' after the 2nd Booster dose. A patient was classified as a responder if they: (1) had positive anti-S antibody at 4 weeks if seronegative after 1st booster dose or (2) if they achieved a titer of >1000 AU/mL at 4 weeks if they were sero-low after 1st booster dose.

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike IgG Responders After the 2nd Booster Dose

12 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 7 patients remained seronegative following administration of Primary vaccination series and 1st booster dose

Rate was determined as the percentage of patients demonstrating booster-induced seroconversion to positive anti-S antibody who had remained seronegative following administration of Primary Vaccination series and 1st Booster dose of BNT162b2, mRNA-1273, or AdCoV2.S COVID vaccine.

Outcome measures

Measure

1st Booster Dose n=7 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Rate of Seroconversion for SARS-CoV-2 Spike Antibody Among Patients Who Remained Seronegative Following 1st Booster Dose

2 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 11 patients were sero-low (IgG \<1000 AU/mL) prior to administration of 2nd booster dose

The percentage of Patients with low anti-Spike antibody, determined to be IgG <1000 AU/mL by assay, who responded following administration of 2nd booster dose. Responses in this context were determined to be those patients with assay results of IgG > 1000 AU/mL.

Outcome measures

Measure

1st Booster Dose n=11 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients With Low Anti-Spike Antibody Who Responded Following 2nd Booster Dose

11 Participants

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The median Anti-S antibody titer following administration of the primary vaccination series and 1st booster dose in Cohort B was determined.

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-Spike Antibody Titer Following Administration of 1st Booster Dose

131.1 AU/mL Interval 50.0 to 432.9

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The median Anti-S antibody titer following administration of the 2nd booster dose (Cohort B) was determined.

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-Spike Antibody Titer Following Administration of 2nd Booster Dose

1700 AU/mL Interval 64.3 to 18627.0

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 14 patients in Cohort B had evaluable T-cell responses

The number of Cohort B patients with evaluable T-cell immune responses who demonstrated positive anti-S antibody (IgG) titers against SARS-CoV-2 following 1st booster dose and prior to 2nd booster dose of vaccine.

Outcome measures

Measure

1st Booster Dose n=14 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Positive Anti-Spike Antibody (IgG) Titer Prior to 2nd Booster Dose

11 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

The percentage of Cohort B patients who demonstrated positive anti-S antibody (IgG) titers against SARS-CoV-2 following administration of 2nd booster dose of vaccine.

Outcome measures

Measure

1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Positive Anti-Spike Antibody (IgG) Titer Following 2nd Booster Dose

17 Participants

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

Neutralization activity against the WT variant was assessed using a neutralization activity assay. The percentage of patients with positive and negative T-cell results are reported.

Outcome measures

Measure	1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Prior to 2nd Booster Dose Positive	12 Participants
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Prior to 2nd Booster Dose Negative	6 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

Neutralization activity against the WT variant was assessed using a neutralization activity assay. The percentage of patients with positive and negative T-cell results are reported.

Outcome measures

Measure	1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Following 2nd Booster Dose Positive	13 Participants
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Following 2nd Booster Dose Negative	5 Participants

SECONDARY outcome

Timeframe: Prior to administration of 2nd booster dose, a minimum of 14-28 days following 1st booster dose, a median of approximately 5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

Neutralization activity against the Omicron BA.1 variant was assessed using a neutralization activity assay. The percentage of patients with positive and negative T-cell results are reported.

Outcome measures

Measure	1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization Against Omicron BA.1 SARS-CoV-2 Variant Prior to 2nd Booster Dose Positive	0 Participants
Neutralization Against Omicron BA.1 SARS-CoV-2 Variant Prior to 2nd Booster Dose Negative	18 Participants

SECONDARY outcome

Timeframe: ~4 weeks after administration of 2nd booster dose, a minimum of 4-6 weeks following 1st booster dose, a median of approximately 6.0-6.5 months

Population: 18 participants were enrolled into the 2nd booster dose cohort. All 18 patients in this cohort had hematologic malignancies. 15 patients received BNT162b2 as their 2nd booster vaccine and 3 patients received Ad26.CoV2.S as their 2nd booster vaccine.

Neutralization activity against the Omicron BA.1 variant was assessed using a neutralization activity assay. The percentage of patients with positive and negative T-cell results are reported.

Outcome measures

Measure	1st Booster Dose n=18 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization Against Omicron BA.1 SARS-CoV-2 Variant Following 2nd Booster Dose Positive	6 Participants
Neutralization Against Omicron BA.1 SARS-CoV-2 Variant Following 2nd Booster Dose Negative	12 Participants

POST_HOC outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 12 patients were on BTK inhibitors prior to the study

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were determined for patients on BTK inhibitors prior to the study

Outcome measures

Measure

1st Booster Dose n=12 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients on Bruton's Tyrosine Kinase (BTK) Inhibitors

0 AU/mL Interval 0.0 to 3393.0

POST_HOC outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 94 patients were not on BTK inhibitors prior to the study

In order to determine association of specific cancer-directed therapies with the booster effect, median change in anti-S antibody titers were determined for patients not on BTK inhibitors prior to the study

Outcome measures

Measure

1st Booster Dose n=94 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Anti-spike Antibody Titers for Patients Not on Bruton's Tyrosine Kinase (BTK) Inhibitors

9355 AU/mL Interval 877.3 to 34410.0

POST_HOC outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 9 patients had prior COVID-19 infection, 96 patients did not have prior COVID-19 infection. Prior COVID-19 infection status was unknown for 1 patient.

Median change in anti-S antibody titer was determined based on previous SARS-CoV-2 (COVID-19) infection status

Outcome measures

Measure	1st Booster Dose n=105 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Change in Anti-Spike Antibody Titer by Prior SARS-CoV-2 (COVID-19) Infection Status Previous COVID-19 infection	19350 AU/mL Interval 9286.0 to 32151.0
Change in Anti-Spike Antibody Titer by Prior SARS-CoV-2 (COVID-19) Infection Status No Previous COVID-19 infection	6706 AU/mL Interval 444.1 to 33831.0

POST_HOC outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 78 patients were administered the BNT162b2 booster and 28 patients were administered the mRNA-1273 booster

Median change in anti-S antibody titer was determined based on the type of booster administered (BNT162b2 or mRNA-1273)

Outcome measures

Measure	1st Booster Dose n=106 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Change in Anti-Spike Antibody Titer Based on Type of Booster Administered BNT162b2	5534 AU/mL Interval 433.8 to 18074.0
Change in Anti-Spike Antibody Titer Based on Type of Booster Administered mRNA-1273	31451 AU/mL Interval 515.5 to 45057.0

POST_HOC outcome

Timeframe: Baseline to 4 weeks after administration of 1st booster dose

Population: 106 total patients analyzed. Breakdowns by age categories described with corresponding median antibody titer results.

To investigate the association of age, median change in anti-S antibody titers were determined for the cohort of patients <65 years old as opposed to the cohort of patients >=65 years old.

Outcome measures

Measure	1st Booster Dose n=106 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Change in Anti-Spike Antibody Titer by Age <65 years old	27451 AU/mL Interval 2641.0 to 50000.0
Change in Anti-Spike Antibody Titer by Age >=65 years old	6152 AU/mL Interval 558.9 to 41765.0

POST_HOC outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 35 patients were found be seronegative after the 1st booster dose

Neutralization activity against the WT variant was assessed in the seronegative cohort using a neutralization activity assay. The percentage of patients with positive and negative results are reported.

Outcome measures

Measure	1st Booster Dose n=35 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Positive	16 Participants
Neutralization Against Wildtype (WT) SARS-CoV-2 Variant Negative	19 Participants

POST_HOC outcome

Timeframe: 4 weeks after administration of 1st booster dose

Population: 35 patients were found be seronegative after the 1st booster dose

Neutralization activity against the BA.1.1529 (Omicron BA.1) variant was assessed in the seronegative cohort using a neutralization activity assay. The percentage of patients with positive and negative results are reported.

Outcome measures

Measure	1st Booster Dose n=35 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.
Neutralization in Seronegative Cohort Against Omicron BA.1 Variant Positive	6 Participants
Neutralization in Seronegative Cohort Against Omicron BA.1 Variant Negative	29 Participants

POST_HOC outcome

Timeframe: ~4-6 months after administration of 1st booster dose

Population: 47 patients completed their 4-6 month follow-up visit following 1st booster dose. All 47 were seropositive at 4 weeks. 36 of these patients had hematologic malignancies and 11 of these patients had solid malignancies. Six patients had received anti-COVID monoclonal antibody therapy as per standard of care between the 4 week and 4-6 months' follow-up period. Nine patients had received a fourth dose of COVID-19 vaccine outside of the context of the study prior to the time of 4-6 months' follow-up.

The percentage of patients with breakthrough SARS-CoV-2 infections was determined.

Outcome measures

Measure

1st Booster Dose n=47 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients With Breakthrough SARS-CoV-2 Infections

4 Participants

POST_HOC outcome

Timeframe: ~4-6 months after administration of 1st booster dose

Population: 47 patients completed their 4-6 month follow-up visit following 1st booster dose. All 47 were seropositive at 4 weeks. 36 of these patients had hematologic malignancies and 11 of these patients had solid malignancies. Six patients had received anti-COVID monoclonal antibody therapy as per standard of care between the 4 week and 4-6 months' follow-up period. Nine patients had received a fourth dose of COVID-19 vaccine outside of the context of the study prior to the time of 4-6 months' follow-up.

The percentage of patients who seroreverted (i.e., no longer had detectable serum antibody) was determined

Outcome measures

Measure

1st Booster Dose n=47 Participants Patients who have a negative SARS-CoV-2 spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2 or mRNA-1273), or 28 days after the adenoviral based Ad26CoV2.S vaccine, received a third/booster mRNA vaccine (initially BNT162b2 per protocol, which was later amended to allow for third mRNA-1273 vaccine after the FDA authorized 'booster' doses in the fall of 2021). Patients then returned for follow-up at 4 weeks and 5-6 months after their third/booster dose, and their labs were repeated.

Percentage of Patients Who Seroreverted

0 Participants

Adverse Events

Booster Dose

Serious events: 1 serious events

Other events: 63 other events

Deaths: 0 deaths

Serious adverse events

Measure

Booster Dose n=106 participants at risk BNT162b2 vaccine: administer an additional dose of the BNT162b2 mRNA vaccine to patients with cancer who have a negative SARS-CoV-2 Spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2/mRNA-1273) or 28 days after the adenoviral based Ad26CoV2.S vaccine.

General disorders Fever

0.94% 1/106 • Number of events 1 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.

Other adverse events

Measure	Booster Dose n=106 participants at risk BNT162b2 vaccine: administer an additional dose of the BNT162b2 mRNA vaccine to patients with cancer who have a negative SARS-CoV-2 Spike IgG at least 14 days after 2 doses of the mRNA vaccines (BNT162b2/mRNA-1273) or 28 days after the adenoviral based Ad26CoV2.S vaccine.
Injury, poisoning and procedural complications Vaccination Complication	51.9% 55/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Vaccination Site Lymphadenopathy	2.8% 3/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Injection Site Reaction	4.7% 5/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Gastrointestinal disorders Nausea	1.9% 2/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Nervous system disorders Headache	5.7% 6/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Fatigue	8.5% 9/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Fever	13.2% 14/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Respiratory, thoracic and mediastinal disorders Cough	5.7% 6/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Chills	3.8% 4/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Metabolism and nutrition disorders Anorexia	0.94% 1/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Gastrointestinal disorders Diarrhea	0.94% 1/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Musculoskeletal and connective tissue disorders Back Pain	0.94% 1/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
Nervous system disorders Dizziness	2.8% 3/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.
General disorders Non-cardiac Chest Pain	1.9% 2/106 • Through study termination, up to 6 months. Patients were observed for a minimum of 15 minutes after their booster vaccinations to monitor for adverse events. Adverse event monitoring continued via administration of a questionnaire at 4 weeks (28 days), 3 months (90 days) and 6 months (180 days) following initial booster dose administration. Additional monitoring timepoints (i.e., 12 months (365 days), and 24 months (730 days)) were not reached as the study was terminated early.

Additional Information

Dr. Balazs Halmos

Montefiore Medical Center

Phone: 718-405-8404

Email: bahalmos@montefiore.org

Results disclosure agreements

• Principal investigator is a sponsor employee
• Publication restrictions are in place