Primary Outcome Measures:
- Number of Participants Reporting Vaccine-associated Serious Adverse Events (SAEs) [ Time Frame: Day 0 through Day 180 after last vaccination ] [ Designated as safety issue: Yes ]
Serious adverse events included any untoward medical occurrence that resulted in death; was life threatening; was a persistent/significant disability/incapacity; required in-patient hospitalization or prolongation thereof; resulted in a congenital anomaly/birth defect; or may have jeopardized the participant or required intervention to prevent one of these outcomes. Association to vaccination was determined by a study clinician licensed to make medical diagnoses.
- Number of Participants Reporting Solicited Local Reactions Based on the Functional Grading Scale After the First Vaccination [ Time Frame: Day 0-7 after first vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of local reactions of pain, tenderness and swelling for 8 days after vaccination (Day 0-7) based on their interference with daily activities. Participants are counted if they reported experiencing the symptom at any severity on any of the 8 days.
- Number of Participants Reporting Solicited Local Reactions Based on the Functional Grading Scale After the Second Vaccination [ Time Frame: Day 0-7 after second vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of local reactions of pain, tenderness and swelling for 8 days after vaccination (Day 0-7) based on their interference with daily activities. Participants are counted if they reported experiencing the symptom at any severity on any of the 8 days.
- Number of Participants Reporting Measured Injection Site Reactions of Swelling and Redness After the First Vaccination [ Time Frame: Day 0-7 after first vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of local reactions of swelling and redness for 8 days after vaccination (Day 0-7). If the reaction was present, the maximum diameter was measured in millimeters (mm). Participants are counted if they reported experiencing the reaction with any measurement greater than 0 mm on any of the 8 days.
- Number of Participants Reporting Measured Injection Site Reactions of Swelling and Redness After the Second Vaccination [ Time Frame: Day 0-7 after second vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of local reactions of swelling and redness for 8 days after vaccination (Day 0-7). If the reaction was present, the maximum diameter was measured in millimeters (mm). Participants are counted if they reported experiencing the reaction with any measurement greater than 0 mm on any of the 8 days.
- Number of Participants Reporting Solicited Systemic Reactions Based on the Functional Grading Scale After the First Vaccination [ Time Frame: Day 0-7 after first vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of systemic symptoms of feverishness, malaise, myalgia, headache, and nausea for 8 days after vaccination (Day 0-7) based on their interference with daily activities. Participants are counted if they reported experiencing the symptom at any severity on any of the 8 days.
- Number of Participants Reporting Solicited Systemic Reactions Based on the Functional Grading Scale After the Second Vaccination [ Time Frame: Day 0-7 after second vaccination ] [ Designated as safety issue: Yes ]
Participants maintained a memory aid to record daily the occurrence of systemic symptoms of feverishness, malaise, myalgia, headache, and nausea for 8 days after vaccination (Day 0-7) based on their interference with daily activities. Participants are counted if they reported experiencing the symptom at any severity on any of the 8 days.
- Number of Participants Reporting Fever After the First Vaccination [ Time Frame: Day 0-7 after first vaccination ] [ Designated as safety issue: Yes ]
Participants were provided with a thermometer and a memory aid on which to record daily oral temperatures for 8 days after vaccination (Day 0-7). The protocol defined fever as oral temperature of 38.0 degrees Celsius or higher. Participants are counted as experiencing fever if they reported oral temperatures of 38.0 degrees Celsius or higher on any of the 8 days.
- Number of Participants Reporting Fever After the Second Vaccination [ Time Frame: Day 0-7 after second vaccination ] [ Designated as safety issue: Yes ]
Participants were provided with a thermometer and a memory aid on which to record daily oral temperatures for 8 days after vaccination (Day 0-7). The protocol defined fever as oral temperature of 38.0 degrees Celsius or higher. Participants are counted as experiencing fever if they reported oral temperatures of 38.0 degrees Celsius or higher on any of the 8 days.
- Number of Participants in the 18-64 Year Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 8-10 Days Following 1 Dose of Vaccine [ Time Frame: Baseline and Day 8-10 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 8-10 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 8-10 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 8-10 titer was an increase by 4-fold or more.
- Number of Participants in the 65 Years and Older Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 8-10 Days Following 1 Dose of Vaccine [ Time Frame: Baseline and Day 8-10 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 8-10 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 8-10 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 8-10 titer was an increase by 4-fold or more.
- Number of Participants in the 18-64 Year Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 21 Days Following 1 Dose of Vaccine [ Time Frame: Baseline and Day 21 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 21 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 8-10 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 8-10 titer was an increase by 4-fold or more.
- Number of Participants in the 65 Years and Older Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 21 Days Following 1 Dose of Vaccine [ Time Frame: Baseline and Day 21 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 21 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 8-10 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 8-10 titer was an increase by 4-fold or more.
- Number of Participants in the 18-64 Year Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus Prior to and at 8-10 Days Following 1 Dose of H1N1 Vaccine [ Time Frame: Day 0 prior to and Day 8-10 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 8-10 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
- Number of Participants in the 65 Years and Older Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus Prior to and at 8-10 Days Following 1 Dose of H1N1 Vaccine [ Time Frame: Day 0 prior to and Day 8-10 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to vaccination and at the 8-10 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
- Number of Participants in the 18-64 Year Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus at 21 Days Following 1 Dose of H1N1 Vaccine [ Time Frame: Day 21 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants at the 21 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
- Number of Participants in the 65 Years and Older Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus at 21 Days Following 1 Dose of H1N1 Vaccine [ Time Frame: Day 21 after first vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants at the 21 day follow up visit for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
Secondary Outcome Measures:
- Number of Participants in the 18-64 Year Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 8-10 and 21 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Baseline and Day 8-10 and 21 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to the initial vaccination as well as 8-10 and 21 days after the second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 21 post vaccination 2 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 21 post vaccination 2 titer was an increase by 4-fold or more.
- Number of Participants in the 65 Years and Older Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 8-10 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Baseline and Day 8-10 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to the initial vaccination and 8-10 days after the second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 21 post vaccination 2 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 21 post vaccination 2 titer was an increase by 4-fold or more.
- Number of Participants in the 65 Years and Older Age Stratum With 4-fold or Greater HAI Antibody Titer Increases Against Influenza H1N1 2009 Virus at 21 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Baseline and Day 21 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants prior to the initial vaccination and 21 days after the second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. A participant met the threshold of a 4-fold rise in titer if the Day 0 titer was less than 1:10 (the assay's lowest level of detection) and the Day 21 post vaccination 2 titer was 1:40 or greater, or the Day 0 titer was greater than or equal to 1:10 and the Day 21 post vaccination 2 titer was an increase by 4-fold or more.
- Number of Participants in the 18-64 Year Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus at 8-10 and 21 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Day 8-10 and Day 21 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants at Day 8-10 and Day 21 post second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
- Number of Participants in the 65 Years and Older Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus at 8-10 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Day 8-10 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants at Day 8-10 post second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
- Number of Participants in the 65 Years and Older Age Stratum With a Serum Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater Against Influenza H1N1 2009 Virus at 21 Days Following 2 Doses of H1N1 Vaccine [ Time Frame: Day 21 after the second vaccination ] [ Designated as safety issue: No ]
Blood was collected from all participants at Day 21 post second vaccination for testing in the HAI assay with Influenza H1N1 2009 virus as the assay antigen. Each sample was tested at least twice according to standard operating procedures and the result of each replicate reported. A participant is counted if the geometric mean of the replicate values was 1:40 or greater.
Recently, a novel swine-origin influenza A/H1N1 virus was identified as a significant cause of febrile respiratory illnesses in Mexico and the United States. It rapidly spread to many countries around the world, prompting the World Health Organization (WHO) to declare a pandemic on June 11, 2009. Data from several cohorts in different age groups that received licensed trivalent seasonal influenza vaccines suggest that these vaccines are unlikely to provide protection against the new virus. In addition, adults are more likely to have measurable levels of serum hemagglutination inhibition assay (HAI) or neutralizing antibody than are children. These data indicate the need to develop vaccines against the new H1N1 strain and suggest that different vaccine strategies (e.g., number of doses, need for adjuvant) may be appropriate for persons in different age groups. The primary safety objective of this study is to assess the safety of the unadjuvanted, inactivated H1N1 vaccine when administered at the 15 or 30 mcg dose. The primary immunogenicity objective is to assess the antibody response following a single dose of unadjuvanted, inactivated H1N1 vaccine, stratified by age of recipient, when administered at the 15 or 30 mcg dose. The secondary immunogenicity objective is to assess the antibody response following 2 doses of unadjuvanted, inactivated H1N1 vaccine, stratified by age of recipient, when administered at the 15 or 30 mcg dose. Participants will include up to 450 healthy adults age 18 and older who have no history of novel influenza H1N1 2009 infection or novel influenza H1N1 2009 vaccination. This is a randomized, double-blinded, Phase II study in healthy males and non-pregnant females designed to investigate the safety, reactogenicity, and immunogenicity of an inactivated influenza H1N1 virus vaccine at 2 dose levels. Subjects will be randomized into 2 dose groups, stratified by age (200 subjects per dose group with 100 subjects per age stratum, 18-64 or greater than or equal to 65 years of age) to receive intramuscular influenza H1N1 vaccine at 15 mcg (Group 1) or 30 mcg (Group 2). The H1N1 vaccine will be administered at Day 0 and Day 21. Following immunization, safety will be measured by assessment of adverse events through 21 days following the last vaccination (Day 42 for those receiving both doses and Day 21 for those who do not receive the second dose), serious adverse events and new-onset chronic medical conditions through 7 months post first vaccination (Day 201), and reactogenicity to the vaccine for 8 days following each vaccination (Day 0-7). Immunogenicity testing will include HAI and neutralizing antibody testing on serum obtained on the day of each vaccination (prior to vaccination), on Day 8-10 after each vaccination, and 21 days following the second vaccination (Day 42).