COVID-19 Booster Vaccine in Autoimmune Disease Non-Responders

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or COVID-19 vaccine given off-study were excluded from the analyses. Participants missing antibody data were considered missing-completely-at-random. Seroconversion was assessed in the subgroup of participants who were anti-COVID-19 antibody negative at Week 0; defined as a result less than or equal to the positive threshold value (spike=10.8424, RBD=14.0858). Anti-COVID-19 antibody negative at Week 0 is defined separately for spike and RBD. Seroconversion was defined as having a result greater than the positive threshold at the Week 4 visit.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or COVID-19 vaccine given off-study were excluded from the analyses. Participants missing antibody data were considered missing-completely-at-random. Seroconversion was assessed in the subgroup of participants who were anti-COVID-19 antibody negative at Week 0; defined as a result less than or equal to the positive threshold value (spike=10.8424, RBD=14.0858). Anti-COVID-19 antibody negative at Week 0 is defined separately for spike and RBD. Seroconversion was defined as having a result greater than the positive threshold at the Week 4 visit.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing antibody data were considered missing-completely-at-random. Fold increase was assessed in the subgroup of participants who were anti-COVID-19 antibody positive at Week 0; defined as having a result greater than the positive threshold value (spike=10.8424, RBD=14.0858). Anti-COVID-19 antibody positive at Week 0 is defined separately for spike and RBD. Fold increase = (antibody response at Week 4)/(antibody response at Week 0).

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing antibody data were considered missing-completely-at-random. Fold increase was assessed in the subgroup of participants who were anti-COVID-19 antibody positive at Week 0; defined as having a result greater than the positive threshold value (spike=10.8424, RBD=14.0858). Anti-COVID-19 antibody positive at Week 0 is defined separately for spike and RBD. Fold increase = (antibody response at Week 4)/(antibody response at Week 0).

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) 3 plex assay (Wu-1 full-length spike, receptor binding domain (RBD), and N proteins). Wu-1 full-length spike and RBD were used to assess vaccine response. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) 3 plex assay (Wu-1 full-length spike, receptor binding domain (RBD), and N proteins). Wu-1 full-length spike and RBD were used to assess vaccine response. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) V-Plex ACE2 neutralization assay which measure antibodies that block the binding of angiotensin-converting enzyme 2 (ACE2) to the SARS-CoV-2 Spike antigens, including variants of the SARS-CoV-2 virus according to the manufacturer's instruction (MSD Catalog # K15654U). Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random. Results are reported as fold inhibition by a sample relative to signal from a 'diluent only' control (maximum ACE2 binding to antigen). Highly neutralizing samples show high fold inhibition whereas negative or low samples show low fold inhibition of ACE2 binding.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) V-Plex ACE2 neutralization assay which measure antibodies that block the binding of angiotensin-converting enzyme 2 (ACE2) to the SARS-CoV-2 Spike antigens, including variants of the SARS-CoV-2 virus according to the manufacturer's instruction (MSD Catalog # K15654U). Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random. Results are reported as fold inhibition by a sample relative to signal from a 'diluent only' control (maximum ACE2 binding to antigen). Highly neutralizing samples show high fold inhibition whereas negative or low samples show low fold inhibition of ACE2 binding.

The Clinical Global Impression of Change (CGI-C) is the clinician's global impression of a participant's clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

The Clinical Global Impression of Change (CGI-C) is the clinician's global impression of a participant's clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

The Physician's Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Physician's Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Hybrid Systemic Lupus Erythematosus Disease Activity Index (hSLEDAI) is a validated, physician-based assessment tool used to measure the extent of lupus disease activity within the past 28 days. hSLEDAI total score is a weighted sum of the presence of 24 lupus disease symptoms and ranges from 0 to 105, with higher scores indicating more lupus disease activity present.

The Hybrid Systemic Lupus Erythematosus Disease Activity Index (hSLEDAI) is a validated, physician-based assessment tool used to measure the extent of lupus disease activity within the past 28 days. hSLEDAI total score is a weighted sum of the presence of 24 lupus disease symptoms and ranges from 0 to 105, with higher scores indicating more lupus disease activity present.

The Thanou Modified Safety of Estrogens in Lupus Erythematosus: National Assessment- Hybrid Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) assesses systemic lupus erythematosus (SLE) disease activity and categorizes mild/moderate or severe flares based on changes in the SLEDAI score, the Physician's Global Assessment (PGA), other disease activity criteria, and hospitalization due to SLE. The hSLEDAI is a validated, physician-based assessment tool used to measure the extent of lupus disease activity within the past 28 days. hSLEDAI total score is a weighted sum of the presence of 24 lupus disease symptoms and ranges from 0 to 105, with higher scores indicating more lupus disease activity present.

The Thanou Modified Safety of Estrogens in Lupus Erythematosus: National Assessment- Hybrid Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) assesses systemic lupus erythematosus (SLE) disease activity and categorizes mild/moderate or severe flares based on changes in the SLEDAI score, the Physician's Global Assessment (PGA), other disease activity criteria, and hospitalization due to SLE. The hSLEDAI is a validated, physician-based assessment tool used to measure the extent of lupus disease activity within the past 28 days. hSLEDAI total score is a weighted sum of the presence of 24 lupus disease symptoms and ranges from 0 to 105, with higher scores indicating more lupus disease activity present.

The Disease Activity Score 28 C-reactive Protein (DAS28-CRP) is: a score on a scale (0 to 10) indicating current activity of rheumatoid arthritis (>5.1=high disease activity; <=3.2=low disease activity; <2.6=remission); a continuous variable which is a composite of 4 variables(the number of tender joints out of 28, the number of swollen joints out of 28 joints, serum C-reactive protein in mg/L (CRP) and subject assessment of disease activity measure on a visual analogue scale (VAS) of 100 mm). Reference: van Gestel AM et al. Arthritis Rheum.1998; 41(10): 1845-50.

The Disease Activity Score 28 C-reactive Protein (DAS28-CRP) is: a score on a scale (0 to 10) indicating current activity of rheumatoid arthritis (>5.1=high disease activity; <=3.2=low disease activity; <2.6=remission); a continuous variable which is a composite of 4 variables(the number of tender joints out of 28, the number of swollen joints out of 28 joints, serum C-reactive protein in mg/L (CRP) and subject assessment of disease activity measure on a visual analogue scale (VAS) of 100 mm). Reference: van Gestel AM et al. Arthritis Rheum.1998; 41(10): 1845-50.

Severe disease flare included onset of new or significant worsening of internal organ involvement requiring hospitalization or change in treatment. Internal organ involvement included scleroderma renal crisis, interstitial lung disease, left or right sided heart failure, pulmonary arterial hypertension on right-sided heart catheterization or other worsening of internal organs.

Severe disease flare included onset of new or significant worsening of internal organ involvement requiring hospitalization or change in treatment. Internal organ involvement included scleroderma renal crisis, interstitial lung disease, left or right sided heart failure, pulmonary arterial hypertension on right-sided heart catheterization or other worsening of internal organs.

The Pemphigus Disease Area Index (PDAI) was developed by the International Pemphigus Committee and measures both activity of and damage due to pemphigus on the skin, scalp, and mucous membranes. Total scores can range from 0 to a possible 263 maximum score, with 250 points representing disease activity (120 points for skin activity, 10 points for scalp activity, and 120 points for mucosal activity) and 13 points representing disease damage. Higher scores reflect worse disease.

The Pemphigus Disease Area Index (PDAI) was developed by the International Pemphigus Committee and measures both activity of and damage due to pemphigus on the skin, scalp, and mucous membranes. Total scores can range from 0 to a possible 263 maximum score, with 250 points representing disease activity (120 points for skin activity, 10 points for scalp activity, and 120 points for mucosal activity) and 13 points representing disease damage. Higher scores reflect worse disease.

Relapse required: either criteria (a) with investigator determination of relapse or criteria (a) and (b): (a) New, recurrent or worsening neurological symptoms attributable to MS, that meet all of the following: i. Appeared or evolved subacutely (over <3 months). ii. Persisting >24 hours. iii. Can't be attributed to confounding factors. iv. Occur ≥30 days after onset of a prior confirmed relapse. (b) New, recurrent or worsening neurological symptoms accompanied by corresponding objective worsening on neurologic examination with an increase of any one of the following compared to the immediate prior assessment: i. ≥0.5 step(s) on the Expanded Disability Status Scale (EDSS), ii. ≥2 points on one Functional Systems Score (FSS), iii. ≥1 point on two or more FSS. Episodic spasms, sexual dysfunction, fatigue, mood change, or bladder/bowel urgency or incontinence will not suffice to establish relapse. Sexual dysfunction and fatigue will not contribute to the EDSS/FSS for assessing relapse.

Relapse required: either criteria (a) with investigator determination of relapse or criteria (a) and (b): (a) New, recurrent or worsening neurological symptoms attributable to MS, that meet all of the following: i. Appeared or evolved subacutely (over <3 months). ii. Persisting >24 hours. iii. Can't be attributed to confounding factors. iv. Occur ≥30 days after onset of a prior confirmed relapse. (b) New, recurrent or worsening neurological symptoms accompanied by corresponding objective worsening on neurologic examination with an increase of any one of the following compared to the immediate prior assessment: i. ≥0.5 step(s) on the Expanded Disability Status Scale (EDSS), ii. ≥2 points on one Functional Systems Score (FSS), iii. ≥1 point on two or more FSS. Episodic spasms, sexual dysfunction, fatigue, mood change, or bladder/bowel urgency or incontinence will not suffice to establish relapse. Sexual dysfunction and fatigue will not contribute to the EDSS/FSS for assessing relapse.

The Juvenile Arthritis Disease Activity Score 10-C-reactive Protein (JADAS10-CRP) is a score on a scale (0 to 40) indicating activity of juvenile idiopathic arthritis. Total active joints are scored 0 to 10, with an active joint count >10 scored as 10 points. The Physician's Global Assessment and Patient's Global Assessment are measured on a 0-10 scale (0 cm, no disease activity to 10 cm, worst disease activity). CRP is normalized to a 0 to 10 scale according to the following formula: (CRP (mg/L) - 10)/10. CRP values <10 mg/L are scored as 0, and CRP >110 mg/L are scored as 10. The final score is given by the simple sum of its component. Higher scores indicate worse disease activity.

The Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Short Form (Version 2.0) will be used to assess trends over time in this state of health measure. The PROMIS-29 consists of 7 domains related to physical, mental and social health. Raw scores are calculated for each domain and translated into a T-score per the PROMIS-29 scoring guide. The T-score rescales the raw score into a standardized score with a mean of 50 and a standard deviation of 10. Physical Function domain score is presented. A higher score represents better functioning for the Physical Function domain.

The Patient-Reported Outcomes Measurement Information System (PROMIS)-29 Short Form (Version 2.0) will be used to assess trends over time in this state of health measure. The PROMIS-29 consists of 7 domains related to physical, mental and social health. Raw scores are calculated for each domain and translated into a T-score per the PROMIS-29 scoring guide. The T-score rescales the raw score into a standardized score with a mean of 50 and a standard deviation of 10. Physical Function domain score is presented. A higher score represents better functioning for the Physical Function domain.

The Patient Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Patient Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Patient Global Impression of Change (PGI-C) is the participant's global impression of their clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

The Patient Global Impression of Change (PGI-C) is the participant's global impression of their clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

All unsolicited adverse events (AEs) (all grades) were collected from Day 1 through Day 28; solicited AEs were collected if they were ongoing at Day 7 (post vaccination); any flares of a secondary autoimmune disease, serious AEs, medically attended AEs, new onset chronic medical conditions, and COVID-19 infections were collected from Day 1 through the end of the participant's study participation. All AEs were classified by system organ class (SOC) and preferred term, according to a standardized thesaurus (Medical Dictionary for Regulatory Activities [MedDRA] version 24.0. Related AEs were defined as "possibly related" (the AE has a reasonable possibility to be related; there is evidence to suggest a causal relationship) or "related" (the adverse event is clearly related). Severity was assessed according to the criteria set forth in the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) 5.0.

All unsolicited adverse events (AEs) (all grades) were collected from Day 1 through Day 28; solicited AEs were collected if they were ongoing at Day 7 (post vaccination); any flares of a secondary autoimmune disease, serious AEs, medically attended AEs, new onset chronic medical conditions, and COVID-19 infections were collected from Day 1 through the end of the participant's study participation. All AEs were classified by system organ class (SOC) and preferred term, according to a standardized thesaurus (Medical Dictionary for Regulatory Activities [MedDRA] version 24.0. Related AEs were defined as "possibly related" (the AE has a reasonable possibility to be related; there is evidence to suggest a causal relationship) or "related" (the adverse event is clearly related). Severity was assessed according to the criteria set forth in the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) 5.0.

An event is considered "serious" if, in the view of either the investigator or Sponsor, it results in any of the following: 1. Death. 2. Life-threatening event: considered "life-threatening" if, in the view of either the investigator or Sponsor, its occurrence places the participant at immediate risk of death. It does not include an AE that, had it occurred in a more severe form, might have caused death. 3. Inpatient hospitalization or prolongation of existing hospitalization. 4. Persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions. 5. Congenital anomaly or birth defect. 6. Important medical events that may not result in death, be life threatening, or require hospitalization may be considered serious when, based upon appropriate medical judgment, they may jeopardize the participant and may require medical or surgical intervention to prevent one of the outcomes listed above.

An event is considered "serious" if, in the view of either the investigator or Sponsor, it results in any of the following: 1. Death. 2. Life-threatening event: considered "life-threatening" if, in the view of either the investigator or Sponsor, its occurrence places the participant at immediate risk of death. It does not include an AE that, had it occurred in a more severe form, might have caused death. 3. Inpatient hospitalization or prolongation of existing hospitalization. 4. Persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions. 5. Congenital anomaly or birth defect. 6. Important medical events that may not result in death, be life threatening, or require hospitalization may be considered serious when, based upon appropriate medical judgment, they may jeopardize the participant and may require medical or surgical intervention to prevent one of the outcomes listed above.

Medically attended adverse event (MAAE) is defined as a hospitalization, emergency room visit, or an otherwise unscheduled visit to or from medical personnel for any reason that is considered possibly related or related to study vaccine.

Medically attended adverse event (MAAE) is defined as a hospitalization, emergency room visit, or an otherwise unscheduled visit to or from medical personnel for any reason that is considered possibly related or related to study vaccine.

A new onset chronic medical condition (NOCMC) is defined as any new ICD diagnosis (per current International Statistical Classification of Diseases and Related Health Problems) that is applied to the study participant during the course of the study, after receipt of the vaccine, that is expected to continue for at least 3 months and requires continued health care intervention.

A new onset chronic medical condition (NOCMC) is defined as any new ICD diagnosis (per current International Statistical Classification of Diseases and Related Health Problems) that is applied to the study participant during the course of the study, after receipt of the vaccine, that is expected to continue for at least 3 months and requires continued health care intervention.

Efficacy measure.

COVID-19 infections (all grades) were confirmed by molecular COVID-19 testing. AEs were classified by system organ class and preferred term according to the Medical Dictionary for Regulatory Activities (MedDRA) version 24.0.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing antibody data were considered missing-completely-at-random. Seroconversion was assessed in the subgroup of participants who were anti-COVID-19 antibody negative at Week 0; defined as a result less than or equal to the positive threshold value (spike=10.8424, RBD=14.0858), defined independently for spike and RBD. Seroconversion was defined as having a result greater than the positive threshold at the Week 4 visit.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center Meso Scale Discovery 3 plex assay. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing antibody data were considered missing-completely-at-random. Fold increase was assessed in the subgroup of participants who were anti-COVID-19 antibody positive at Week 0; defined as having a result greater than the positive threshold value (spike=10.8424, RBD=14.0858), defined independently for spike and RBD. Fold increase = (antibody response at Week 4)/(antibody response at Week 0).

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) 3 plex assay (Wu-1 full-length spike, receptor binding domain (RBD), and N proteins). Wu-1 full-length spike and RBD were used to assess vaccine response. For concentrations below the lower limit of detection (LLOD), numeric values equivalent to LLOD/2 were assigned; concentrations above the upper limit of quantification were reported without adjustments. Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random.

Antibody response was measured using the National Institute of Allergy and Infectious Disease Vaccine Research Center (NIAID-VRC) Meso Scale Discovery (MSD) V-Plex ACE2 neutralization assay which measure antibodies that block the binding of angiotensin-converting enzyme 2 (ACE2) to the SARS-CoV-2 Spike antigens, including variants of the SARS-CoV-2 virus according to the manufacturer's instruction (MSD Catalog # K15654U). Antibody results collected after a documented COVID-19 infection, monoclonal antibody use, or a COVID-19 vaccine given off-study were excluded from the analyses. Participants with missing anti-COVID-19 antibody response data were considered to be missing-completely-at-random. Results are reported as fold inhibition by a sample relative to signal from a 'diluent only' control (maximum ACE2 binding to antigen). Highly neutralizing samples show high fold inhibition whereas negative or low samples show low fold inhibition of ACE2 binding.

The Clinical Global Impression of Change (CGI-C) is the clinician's global impression of a participant's clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

The Physician's Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Systemic Lupus Erythematosus Disease Activity Index (SLEDAI)-2K is a validated, physician-based assessment tool used to measure the extent of lupus disease activity within the past 28 days. SLEDAI-2K total score is a weighted sum of the presence of 24 lupus disease symptoms and ranges from 0 to 105, with higher scores indicating more lupus disease activity present.

The Patient Global Assessment of the participant's current disease activity is assessed on a 10 cm linear horizontal visual analog scale, where the left hand extreme of the line is considered "Very Good" (0 cm, no disease activity) and the right hand extreme is considered "Very Bad" (10 cm, severe disease activity).

The Patient Global Impression of Change (PGI-C) is the participant's global impression of their clinical condition in terms of change relative to the start of treatment. Change is rated on a 7-point scale from 1 (very much improved) to 7 (very much worse). Higher score = more affected.

All unsolicited adverse events (AEs) (all grades) were collected from Day 1 through Day 28; solicited AEs were collected if they were ongoing at Day 7 (post vaccination); any flares of a secondary autoimmune disease, serious AEs, medically attended AEs, new onset chronic medical conditions, and COVID-19 infections were collected from Day 1 through the end of the participant's study participation. All AEs were classified by system organ class (SOC) and preferred term, according to a standardized thesaurus (Medical Dictionary for Regulatory Activities [MedDRA] version 24.0. Related AEs were defined as "possibly related" (the AE has a reasonable possibility to be related; there is evidence to suggest a causal relationship) or "related" (the adverse event is clearly related). Severity was assessed according to the criteria set forth in the National Cancer Institute's Common Terminology Criteria for Adverse Events (CTCAE) 5.0.

An event is considered "serious" if, in the view of either the investigator or Sponsor, it results in any of the following: 1. Death. 2. Life-threatening event: considered "life-threatening" if, in the view of either the investigator or Sponsor, its occurrence places the participant at immediate risk of death. It does not include an AE that, had it occurred in a more severe form, might have caused death. 3. Inpatient hospitalization or prolongation of existing hospitalization. 4. Persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions. 5. Congenital anomaly or birth defect. 6. Important medical events that may not result in death, be life threatening, or require hospitalization may be considered serious when, based upon appropriate medical judgment, they may jeopardize the participant and may require medical or surgical intervention to prevent one of the outcomes listed above.

Medically attended adverse event (MAAE) is defined as a hospitalization, emergency room visit, or an otherwise unscheduled visit to or from medical personnel for any reason that is considered possibly related or related to study vaccine.

A new onset chronic medical condition (NOCMC) is defined as any new ICD diagnosis (per current International Statistical Classification of Diseases and Related Health Problems) that is applied to the study participant during the course of the study, after receipt of the vaccine, that is expected to continue for at least 3 months and requires continued health care intervention.

COVID-19 infections (all grades) were confirmed by molecular COVID-19 testing. AEs were classified by system organ class and preferred term according to the Medical Dictionary for Regulatory Activities (MedDRA) version 24.0.