A Phase IV, randomized, multicenter trial to assess the immunogenicity and safety of BioThrax® in varying dose regimens with the primary objective of obtaining information on possible dose-sparing strategies in the event of a major biothreat.
This is a Phase IV, randomized, open-label immunogenicity and safety study to evaluate four dosing regimens of BioThrax® for Post-Exposure Prophylaxis (PEP) for anthrax. BioThrax® will be administered as a subcutaneous (SC) injection for the primary series and will be administered as an intramuscular (IM) injection for the boost. The four dosing regimens are: 0.50mL BioThrax® on Days 0, 14, and 6 month boost; 0.50mL BioThrax® on Days 0, 28 and 6 month boost; 0.50mL BioThrax® on Days 0, 14, 28 and 6 month boost and 0.25mL BioThrax® on Days 0, 14, and 28, 6 month boost with 0.50ml IM Approximately 300 subjects will be randomized 1:1:1:1 to one of the four study arms. Enrollment will be stratified by gender, with approximately equal numbers of males and females (18 through 65 years) enrolled into each dosing regimen. The Primary objective is to evaluate the immunogenicity of the four dosing regimens of BioThrax® using the Toxin Neutralization Assay (TNA). The secondary objective is to evaluate the safety of the four dosing regimens of BioThrax®.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
NONE
Enrollment
328
BioThrax® is a sterile, milky white suspension made from cell free filtrates of microaerophilic cultures of an avirulent, nonencapsulated strain of Bacillus anthracis, will be administered as a 0.50mL IM injection 6 month boost for all groups
BioThrax® will be administered as: Arm A: 0.50mL SC injection on Days 0 and 14; Arm B: 0.50mL SC injection on Days 0 and 28; Arm C: 0.50mL SC injection on Days 0, 14 and 28; Arm D: 0.25 mL SC injection on Days 0, 14 and 28.
Emory Children's Center - Pediatric Infectious Diseases
Atlanta, Georgia, United States
Cincinnati Children's Hospital Medical Center - Infectious Diseases
Cincinnati, Ohio, United States
Baylor College of Medicine - Molecular Virology and Microbiology
Houston, Texas, United States
Group Health Research Institute - Seattle
Seattle, Washington, United States
Number of Participants With a Four-fold or Greater Increase From Baseline in Toxin Neutralization Antibody Assay (TNA) 50 Percent Neutralization Factor ( NF50 ) Antibody Titer
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the toxin neutralization antibody assay to determine the NF50 antibody titer. A participant met the threshold of a 4-fold rise in NF50 antibody titer if the post vaccination titer was an increase by 4-fold or more from the baseline (Day 0) titer.
Time frame: Days 0, 7, 14, 21, 28 35, 42, 49, 56, 63, 70, 84 and 100
Geometric Mean Concentration (GMC) of Enzyme-linked Immunosorbent Assay (ELISA) Antibody Against the Protective Antigen (Anti-PA IgG)
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the ELISA assay to determine the anti-PA IgG antibody concentration. The geometric mean of subjects' visit-specific titers were calculated along with the 95% confidence intervals. If the antibody titer was below the lower limit of quantification (LLOQ) for the assay, half the value of LLOQ (4.64) was imputed. When all subjects' titers were below LLOQ resulting in no variability within the group, the 95% CI was not calculated.
Time frame: Days 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84 and 100.
Number of Participants Reporting Solicited Injection Site Reactogenicity Symptoms in the Eight Days Following Vaccination at Day 0 by Maximum Severity
Participants maintained a memory aid to record daily the occurrence of local reactions for 8 days after vaccination based on their interference with daily activities (pain, itchiness, warmth, and tenderness at injection site, arm motion limitation) or based on a quantitative measurement of the reaction (edema, erythema). In the subjective grading scale, severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. For the quantitative scale, severe reactions greater than 100 millimeters (mm), moderate reactions were 51-100 mm, and mild reactions were 25-50 mm. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
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Time frame: Days 0-7 after vaccination at Day 0
Number of Participants Reporting Solicited Injection Site Reactogenicity Symptoms in the Eight Days Following Vaccination at Day 14 by Maximum Severity
Participants maintained a memory aid to record daily the occurrence of local reactions for 8 days after vaccination based on their interference with daily activities (pain, itchiness, warmth, and tenderness at injection site, arm motion limitation) or based on a quantitative measurement of the reaction (edema, erythema). In the subjective grading scale, severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. For the quantitative scale, severe reactions greater than 100 millimeters (mm), moderate reactions were 51-100 mm, and mild reactions were 25-50 mm. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Day 14
Number of Participants Reporting Solicited Injection Site Reactogenicity Symptoms in the Eight Days Following Vaccination at Day 28 by Maximum Severity
Participants maintained a memory aid to record daily the occurrence of local reactions for 8 days after vaccination based on their interference with daily activities (pain, itchiness, warmth, and tenderness at injection site, arm motion limitation) or based on a quantitative measurement of the reaction (edema, erythema). In the subjective grading scale, severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. For the quantitative scale, severe reactions greater than 100 millimeters (mm), moderate reactions were 51-100 mm, and mild reactions were 25-50 mm. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Day 28
Number of Participants Reporting Solicited Injection Site Reactogenicity Symptoms in the Eight Days Following the 6-month Boost by Maximum Severity
Participants maintained a memory aid to record daily the occurrence of local reactions for 8 days after the 6-month intramuscular boost vaccination based on their interference with daily activities (pain, itchiness, warmth, and tenderness at injection site, arm motion limitation) or based on a quantitative measurement of the reaction (edema, erythema). In the subjective grading scale, severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. For the quantitative scale, severe reactions greater than 100 millimeters (mm), moderate reactions were 51-100 mm, and mild reactions were 25-50 mm. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Month 6
Number of Participants With Injection Site Edema and Erythema With a Size of Greater Than 120 Millimeters (mm)
Participants were given a ruler with the memory aid to measure the occurrence of edema (swelling) and erythema (redness) daily for at least 8 days after each vaccination. Participants are counted in this outcome measure if they had measurements of greater than 120 mm in the 8-day period after at least one vaccination, first separately for edema and erythema, and in the last category, edema and/or erythema, if they had either or both reactions of greater than 120 mm.
Time frame: Days 0-7 after each vaccination
TNA NF50 Geometric Mean Titers (GMT) at Days 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84 and 100.
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the toxin neutralization antibody assay to determine the NF50 antibody titer. The geometric mean of subjects' visit-specific titers were calculated along with the 95% confidence intervals. If the antibody titer was below the lower limit of quantification (LLOQ) for the assay, half the value of LLOQ (0.03) was imputed. When all subjects' titers were below LLOQ resulting in no variability within the group, the 95% CI was not calculated.
Time frame: Days 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84 and 100.
Peak Geometric Mean Concentration (GMC) of ELISA Anti-PA IgG Antibody Through Day 100
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the ELISA assay to determine the anti-PA IgG antibody concentration. To determine the group peak GMC, the highest antibody concentration assessed for each subject at any post vaccination visit through Day 100 was determined. The geometric mean of subjects' peak concentrations was calculated along with the 95% confidence intervals.
Time frame: Day 7 through Day 100
Number of Participants Reporting Solicited Subjective Systemic Symptoms for Eight Days After Vaccination at Day 0 by Maximum Severity.
Participants maintained a memory aid to record daily the occurrence of solicited systemic reactions of fatigue, muscle aches, and headache for 8 days after vaccination based on their interference with daily activities. Severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Day 0
Number of Participants Reporting Solicited Subjective Systemic Symptoms for Eight Days After Vaccination at Day 14 by Maximum Severity.
Participants maintained a memory aid to record daily the occurrence of solicited systemic reactions of fatigue, muscle aches, and headache for 8 days after vaccination based on their interference with daily activities. Severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Day 14
Number of Participants Reporting Solicited Subjective Systemic Symptoms for Eight Days After Vaccination at Day 28 by Maximum Severity.
Participants maintained a memory aid to record daily the occurrence of solicited systemic reactions of fatigue, muscle aches, and headache for 8 days after vaccination based on their interference with daily activities. Severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Day 28
Number of Participants Reporting Solicited Subjective Systemic Symptoms for Eight Days After the 6-month Boost Vaccination by Maximum Severity.
Participants maintained a memory aid to record daily the occurrence of solicited systemic reactions of fatigue, muscle aches, and headache for 8 days after the 6-month intramuscular boost vaccination based on their interference with daily activities. Severe reactions prevented daily activities, moderate reactions interfered with but did not prevent daily activities, and mild reactions did not interfere with daily activities. Participants are counted by the maximum severity they reported experiencing the reaction on any of the 8 days.
Time frame: Days 0-7 after vaccination at Month 6
Number of Participants Reporting Fever in the Eight Days After Vaccination at Day 0 by Maximum Severity
Participants were given a thermometer with a memory aid to record their oral temperature at least once daily, encouraged to be at the same time each day, but at any time the participant felt they may have a fever. The highest temperature assessed for each day was reported and graded according to the protocol grading scale of severe being greater than or equal to 39 degrees Celsius, moderate 38.5-38.9 degrees Celsius, and mild 38.0-38.4 degrees Celsius. Participants are counted by the maximum severity they reported experiencing fever on any of the 8 days.
Time frame: Day 0-7 after vaccination at Day 0
Number of Participants Reporting Fever in the Eight Days After Vaccination at Day 14 by Maximum Severity
Participants were given a thermometer with a memory aid to record their oral temperature at least once daily, encouraged to be at the same time each day, but at any time the participant felt they may have a fever. The highest temperature assessed for each day was reported and graded according to the protocol grading scale of severe being greater than or equal to 39 degrees Celsius, moderate 38.5-38.9 degrees Celsius, and mild 38.0-38.4 degrees Celsius. Participants are counted by the maximum severity they reported experiencing fever on any of the 8 days.
Time frame: Day 0-7 after vaccination at Day 14
Number of Participants Reporting Fever in the Eight Days After Vaccination at Day 28 by Maximum Severity
Participants were given a thermometer with a memory aid to record their oral temperature at least once daily, encouraged to be at the same time each day, but at any time the participant felt they may have a fever. The highest temperature assessed for each day was reported and graded according to the protocol grading scale of severe being greater than or equal to 39 degrees Celsius, moderate 38.5-38.9 degrees Celsius, and mild 38.0-38.4 degrees Celsius. Participants are counted by the maximum severity they reported experiencing fever on any of the 8 days.
Time frame: Day 0-7 after vaccination at Day 28
Number of Participants Reporting Fever in the Eight Days After the 6-month Boost Vaccination by Maximum Severity
Participants were given a thermometer with a memory aid to record their oral temperature at least once daily, encouraged to be at the same time each day, but at any time the participant felt they may have a fever. The highest temperature assessed for each day was reported and graded according to the protocol grading scale of severe being greater than or equal to 39 degrees Celsius, moderate 38.5-38.9 degrees Celsius, and mild 38.0-38.4 degrees Celsius. Participants are counted by the maximum severity they reported experiencing fever on any of the 8 days.
Time frame: Day 0-7 after vaccination at Month 6
Number of Subjects With a Four-fold or Greater Increase From Baseline in Enzyme-linked Immunosorbent Assay (ELISA) Antibody Concentration Against the Protective Antigen (Anti-PA IgG)
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the ELISA assay to determine the anti-PA IgG antibody concentration. A participant met the threshold of a 4-fold rise in anti-PA IgG antibody concentration if the post vaccination concentration was an increase by 4-fold or more from the baseline (Day 0) concentration.
Time frame: Days 0, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 84 and 100.
TNA NF50 Peak Geometric Mean Titer (GMT) Antibody Response Through Day 100
Blood was collected from all participants prior to vaccination and at scheduled follow up visits weekly through Day 70, at Day 84 and at Day 100 for testing in the toxin neutralization antibody assay to determine the NF50 antibody titer. To determine the group peak GMT, the highest titer assessed for each subject at any post vaccination visit through Day 100 was determined. The geometric mean of each subjects' peak titers was calculated along with the 95% confidence intervals.
Time frame: Day 7 through Day 100