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Higher Dose Intradermal H5 Vaccine

A Phase I/II Randomized, Double-Blinded Placebo-Controlled Trial to Evaluate the Safety, Reactogenicity, and Immunogenicity of Immunization With Inactivated Subvirion Influenza A/H5N1 Vaccine Administered by the Intradermal or the Intramuscular Route Among Healthy Adults

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00439335
Enrollment
227
Registered
2007-02-23
Start date
2007-03-31
Completion date
2008-02-29
Last updated
2013-04-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza

Keywords

Influenza, vaccine, A/H5N1

Brief summary

This study will compare the influenza A/H5N1 virus vaccine given by injection in the muscle versus injection in the skin in healthy adults. The study will look at the safety of the injections, how the body reacts, and what the body's immune response does when the vaccine is given in the muscle versus in the skin. The study will look at 226 healthy volunteers, ages 18-49 years old. Study procedures will include getting 2 doses of vaccine 28 days apart, physical exams, follow-up clinic visits to check the places on the body where each vaccine was given, and blood sample collections. Volunteers will complete a memory aid by writing down temperatures and health changes for 7 days after each vaccination. Volunteers will be involved in the study for up to 241 days.

Detailed description

Influenza A viruses have the potential to cause worldwide epidemics and/or pandemics resulting in significant morbidity and mortality. Two-hundred twenty-six healthy male and female subjects aged 18 to 49 years, inclusive, in the United States (US) will be enrolled into this single-center, randomized, double-blinded, placebo-controlled trial of intradermal (ID) and intramuscular (IM) injection with subvirion (SV) inactivated influenza A/H5N1 vaccine. The study will have two vaccine groups. Vaccine group 1: the subject will receive 0.1 mL of H5 Hemagglutination (HA) by the ID route in one arm and 0.1 mL of saline placebo by the IM route in the other arm. Vaccine group 2: the subject will receive 0.1 mL of H5 HA by the IM route in one arm and 0.1 mL of saline placebo by the ID route in the other arm. All eligible subjects will be enrolled and randomized 1:1 (113 subjects per vaccine group) to either vaccine group 1 or vaccine group 2. All subjects will receive two doses of approximately 30micrograms of H5 HA by their assigned route, either IM or ID, separated by approximately 28 days. At each vaccination visit, all subjects will also receive a saline placebo in the opposite arm by the different route as their vaccine route (i.e. if vaccine is administered by the ID route in one arm, then a saline placebo will be administered by the IM route in the opposite arm). The second vaccine dose will be administered by the same route as per vaccine group assigned at original randomization. Subjects will be observed in the clinic for approximately 15 minutes after each vaccination. Subjects will return on Day 2 for arm check and assessment of adverse events. All subjects will maintain a memory aid recording oral temperature, and systemic and local adverse events for 7 days after each vaccination. They will return to clinic on Day 8 for adverse event (AE) assessment, concomitant medication assessment, a targeted physical exam (if indicated), and review of memory aid. AE data will be captured Day 0 through Day 56. Serious AE data will be captured from Day 0 through the end of each subject's participation in the study (approximately 7 months). The subjects, staff assessing subjects, and lab personnel will be blinded. Serum for immunogenicity evaluations will be obtained prior to the first vaccination, at Day 0; prior to the second vaccination, at Day 28; on Day 56 and approximately Day 208 (7months after dose 1). The primary objectives are to compare the immunogenicity of a similar dosage level of a subvirion inactivated influenza A/H5N1 vaccine given by ID or IM injection one month after receipt of the second dose of vaccine and to compare the safety and reactogenicity of ID and IM immunization at a similar dosage level of a subvirion inactivated influenza A/H5N1 vaccine among healthy young adults. The secondary objective is to evaluate serum antibody responses approximately 1 and 7 months after the first vaccination. This study is linked to Division of Microbiology and Infectious Diseases protocol 07-0022.

Interventions

Inactivated influenza A/H5N1 vaccine formulated to a concentration of HA greater than or equal to 300 mcg/mL administered via intramuscular (IM) injection. Vaccine will be administered to each subject at Days 0 and 28.

The placebo will be 0.1 mL of saline administered by the IM route.

The placebo will be 0.1 mL of saline administered by the ID route.

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 49 Years
Healthy volunteers
Yes

Inclusion criteria

* Male or non-pregnant female between the ages of 18 and 49 years, inclusive. * Women of childbearing potential (not surgically sterile or post menopausal for greater than or equal to 1 year) must agree to practice adequate contraception (i.e., barrier method, abstinence, intrauterine devices, or licensed hormonal methods) for the entire study period. * Is in good health, as determined by vital signs (heart rate less than 100 beats per minute; blood pressure: systolic less than or equal to 140 mm Hg and greater than or equal to 90 mm Hg; diastolic less than or equal to 90 mm Hg; oral temperature less than 100.0 degrees Fahrenheit), medical history to ensure stable medical condition (see definition below) and a targeted physical examination based on medical history. Stable medical condition - no recent change in prescription medication, dose, or frequency of medication in the last 3 months and health outcomes of the specific disease are considered to be within acceptable limits in the last 6 months. Any change that is due to change of health care provider, insurance company, etc, or is done for financial reasons, as long as in the same class of medication, will not be considered a violation of the inclusion criterion. Any change to prescription medication due to improvement of a disease outcome will not be considered a violation of the inclusion criterion. * Able to understand and comply with planned study procedures. * Provides written informed consent prior to initiation of any study procedures.

Exclusion criteria

* Has a known allergy to eggs or other components of the vaccine. * Has a positive urine or serum pregnancy test prior to vaccination (if female of childbearing potential), is breastfeeding, or has the intention to become pregnant during the study period. * Immunosuppression as a result of an underlying illness or treatment, or use of anti-cancer chemotherapy or radiation therapy within the preceding 36 months. * Has an active neoplastic disease or a history of any hematologic malignancy. * Long term use of oral or parenteral steroids, high-dose inhaled steroids (greater than 800 mcg/day of beclomethasone dipropionate or equivalent) within the preceding 6 months (nasal and topical steroids are allowed). * Has a history of receiving immunoglobulin or other blood product within the 3 months prior to vaccination in this study. * Has a diagnosis of schizophrenia, Bi-polar disease or other major psychiatric diagnosis. * Has been hospitalized for psychiatric illness, history of suicide attempt or confinement for danger to self or others. * Is receiving psychiatric drugs (aripiprazole, clozapine, ziprasidone, haloperidol, molindone, loxapine, thioridazine, thiothixene, pimozide, fluphenazine, risperidone, mesoridazine, quetiapine, trifluoperazine, trifluopromazine, chlorprothixene, chlorpromazine, perphenazine, olanzapine, carbamazepine, divalproex sodium, lithium carbonate or lithium citrate). Subjects who are receiving a single antidepressant drug and are stable for at least 3 months prior to enrollment, without de-compensating symptoms will be allowed to be enrolled in the study. * Has received any other licensed vaccines within 2 weeks (for inactivated vaccines) or 4 weeks (for live vaccines) prior to vaccination in this study. * Has an acute or chronic medical condition that, in the opinion of the investigator, would render vaccination unsafe or would interfere with the evaluation of responses (this includes, but is not limited to: known chronic liver disease, significant renal disease, unstable or progressive neurological disorders, diabetes mellitus, and transplant recipients). * Has a history of severe reactions following immunization with contemporary influenza virus vaccines. * Has a moderate to severe acute illness and/or an oral temperature greater than 100.4 degrees Fahrenheit, within 1 week of vaccination. * Known active human immunodeficiency virus, hepatitis B, or hepatitis C infection. * History of alcohol or drug abuse in the 5 years prior to enrollment. * Presence of any active skin disease on upper arms that could impact study product delivery or site assessment. * Has a history of Guillain Barre syndrome. * Received an experimental agent (vaccine, drug, biologic, device, blood product, or medication) within 1 month prior to vaccination in this study, or expects to receive an experimental agent during the 7-month study period. * Participated in an Influenza A/H5 vaccine study in the past in a group receiving vaccine (but does not exclude documented placebo recipients). * Is enrolled or planning to enroll in another interventional trial at any time between receipt of the first dose of vaccine and the end of the study (approximately 7 months after receipt of the first dose). * Has any condition that would, in the opinion of the site investigator, place the subject at an unacceptable risk of injury or render the subject unable to meet the requirements of the protocol.

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 2Approximately Day 56.Number of participants in each vaccine group achieving a 4-fold or greater increase in serum hemagglutination inhibition (HAI) antibody titers against influenza A/H5N1 virus 28 days after receipt of the second dose of vaccine
Number of Participants Spontaneously Reporting Any Serious Adverse Event.Through Day 208.Any untoward medical occurrence that resulted in death, persistent/significant disability/incapacity, required in-patient hospitalization or prolongation thereof, was life threatening or a congenital anomaly/birth defect in offspring of a study subject; or may have jeopardized the participant or required intervention to prevent one of the outcomes.
Occurrence of Unsolicited Symptoms During a 28-day Surveillance Period Following Vaccinations at Days 0 and 28.Through approximately Day 56The number of participants spontaneously reporting any symptom (defined as any Adverse Event considered associated with the product) within 28 days of vaccination. Participants are counted only once but may have experienced events on multiple occasions.
Occurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.7 days after each vaccinationThe number of participants reporting fever, feverishness, malaise, myalgia, headache and nausea. Participants are counted only once for each symptom but may have experienced symptoms on multiple occasions.
Occurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.7 days after each vaccinationThe number of participants reporting pain, tenderness, itching, induration, erythema, and pigmentation. Participants are counted only once for each symptom but may have experienced symptoms on multiple occasions.

Secondary

MeasureTime frameDescription
Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers 7 Months After Dose 1.Approximately Day 208Number of participants achieving a 4-fold or greater increase in HAI antibody titers against influenza A/H5N1 virus in each vaccine group seven months after receipt of the first dose of vaccine.
HAI Geometric Mean Titer (GMT) After Dose 2Approximately Day 56.HAI geometric mean titer (GMT) against influenza A/H5N1 virus in each vaccine group 28 days after receipt of the second dose of vaccine.
Number of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 at 7 Months After Dose 1.Approximately Day 208Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group 7 months after receipt of the first dose of vaccine.
HAI GMT at 7 Months After Dose 1Approximately Day 208HAI GMT against influenza A/H5N1 virus in each vaccine group seven months after receipt of the first dose of vaccine.
Number of Participants Achieving a HAI Titer of Greater Than or Equal to 40 After Dose 2Approximately Day 56Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group 28 days after receipt of the second dose of vaccine
Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 1.Approximately Day 28Number of participants achieving a 4-fold or greater increase in HAI antibody titers against influenza A/H5N1 virus in each vaccine group one month after receipt of the first dose.
HAI GMT After Dose 1Approximately Day 28HAI GMT against influenza A/H5N1 virus one month after receipt of the first dose of vaccine.
Number of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 After Dose 1.Approximately Day 28Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group one month after receipt of the first dose of vaccine.

Countries

United States

Participant flow

Recruitment details

Healthy ambulatory adults were recruited from the surrounding community of the research clinic from March 14, 2007 to June 20, 2007.

Participants by arm

ArmCount
H5 HA ID
Vaccine group H5 HA ID: the subject will receive 0.1 mL of H5 HA by the ID route in one arm and 0.1 mL of saline placebo by the IM route in the other arm.
113
H5 HA IM
Vaccine group H5 HA IM: the subject will receive 0.1 mL of H5 HA by the IM route in one arm and 0.1 mL of saline placebo by the ID route in the other arm.
114
Total227

Baseline characteristics

CharacteristicH5 HA IMH5 HA IDTotal
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
114 Participants113 Participants227 Participants
Age Continuous30.5 years
STANDARD_DEVIATION 8
29.7 years
STANDARD_DEVIATION 7.4
30.1 years
STANDARD_DEVIATION 7.7
Region of Enrollment
United States
114 participants113 participants227 participants
Sex: Female, Male
Female
60 Participants74 Participants134 Participants
Sex: Female, Male
Male
54 Participants39 Participants93 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
— / —— / —
other
Total, other adverse events
113 / 113114 / 114
serious
Total, serious adverse events
2 / 1132 / 114

Outcome results

Primary

Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 2

Number of participants in each vaccine group achieving a 4-fold or greater increase in serum hemagglutination inhibition (HAI) antibody titers against influenza A/H5N1 virus 28 days after receipt of the second dose of vaccine

Time frame: Approximately Day 56.

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 247 Participants
H5 HA IMNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 240 Participants
Primary

Number of Participants Spontaneously Reporting Any Serious Adverse Event.

Any untoward medical occurrence that resulted in death, persistent/significant disability/incapacity, required in-patient hospitalization or prolongation thereof, was life threatening or a congenital anomaly/birth defect in offspring of a study subject; or may have jeopardized the participant or required intervention to prevent one of the outcomes.

Time frame: Through Day 208.

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Spontaneously Reporting Any Serious Adverse Event.2 Participants
H5 HA IMNumber of Participants Spontaneously Reporting Any Serious Adverse Event.2 Participants
Primary

Occurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.

The number of participants reporting pain, tenderness, itching, induration, erythema, and pigmentation. Participants are counted only once for each symptom but may have experienced symptoms on multiple occasions.

Time frame: 7 days after each vaccination

ArmMeasureGroupValue (NUMBER)
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Pain23 Participants
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Tenderness93 Participants
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Itching95 Participants
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Induration113 Participants
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Erythema113 Participants
H5 HA IDOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Pigmentation70 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Erythema59 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Pain61 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Induration34 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Tenderness91 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Pigmentation2 Participants
H5 HA IMOccurrence of Solicited Local Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Itching8 Participants
Primary

Occurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.

The number of participants reporting fever, feverishness, malaise, myalgia, headache and nausea. Participants are counted only once for each symptom but may have experienced symptoms on multiple occasions.

Time frame: 7 days after each vaccination

ArmMeasureGroupValue (NUMBER)
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Fever2 Participants
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Feverishness11 Participants
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Malaise40 Participants
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Myalgia19 Participants
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Headache53 Participants
H5 HA IDOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Nausea14 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Headache45 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Fever2 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Myalgia23 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Feverishness14 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Nausea13 Participants
H5 HA IMOccurrence of Solicited Systemic Symptoms During a 7-day Surveillance Period (Systematically Collected) Following Vaccinations at Days 0 and 28.Malaise39 Participants
Primary

Occurrence of Unsolicited Symptoms During a 28-day Surveillance Period Following Vaccinations at Days 0 and 28.

The number of participants spontaneously reporting any symptom (defined as any Adverse Event considered associated with the product) within 28 days of vaccination. Participants are counted only once but may have experienced events on multiple occasions.

Time frame: Through approximately Day 56

ArmMeasureValue (NUMBER)
H5 HA IDOccurrence of Unsolicited Symptoms During a 28-day Surveillance Period Following Vaccinations at Days 0 and 28.39 Participants
H5 HA IMOccurrence of Unsolicited Symptoms During a 28-day Surveillance Period Following Vaccinations at Days 0 and 28.26 Participants
Secondary

HAI Geometric Mean Titer (GMT) After Dose 2

HAI geometric mean titer (GMT) against influenza A/H5N1 virus in each vaccine group 28 days after receipt of the second dose of vaccine.

Time frame: Approximately Day 56.

ArmMeasureValue (GEOMETRIC_MEAN)
H5 HA IDHAI Geometric Mean Titer (GMT) After Dose 225.2 Antibody Titer
H5 HA IMHAI Geometric Mean Titer (GMT) After Dose 218.1 Antibody Titer
Secondary

HAI GMT After Dose 1

HAI GMT against influenza A/H5N1 virus one month after receipt of the first dose of vaccine.

Time frame: Approximately Day 28

ArmMeasureValue (GEOMETRIC_MEAN)
H5 HA IDHAI GMT After Dose 113.1 Antibody titer
H5 HA IMHAI GMT After Dose 111.9 Antibody titer
Secondary

HAI GMT at 7 Months After Dose 1

HAI GMT against influenza A/H5N1 virus in each vaccine group seven months after receipt of the first dose of vaccine.

Time frame: Approximately Day 208

ArmMeasureValue (GEOMETRIC_MEAN)
H5 HA IDHAI GMT at 7 Months After Dose 110.0 Antibody Titer
H5 HA IMHAI GMT at 7 Months After Dose 18.9 Antibody Titer
Secondary

Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers 7 Months After Dose 1.

Number of participants achieving a 4-fold or greater increase in HAI antibody titers against influenza A/H5N1 virus in each vaccine group seven months after receipt of the first dose of vaccine.

Time frame: Approximately Day 208

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers 7 Months After Dose 1.17 Participants
H5 HA IMNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers 7 Months After Dose 1.16 Participants
Secondary

Number of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 1.

Number of participants achieving a 4-fold or greater increase in HAI antibody titers against influenza A/H5N1 virus in each vaccine group one month after receipt of the first dose.

Time frame: Approximately Day 28

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 1.25 Participants
H5 HA IMNumber of Participants Achieving a 4-fold or Greater Increase in HAI Antibody Titers After Dose 1.29 Participants
Secondary

Number of Participants Achieving a HAI Titer of Greater Than or Equal to 40 After Dose 2

Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group 28 days after receipt of the second dose of vaccine

Time frame: Approximately Day 56

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a HAI Titer of Greater Than or Equal to 40 After Dose 248 Participants
H5 HA IMNumber of Participants Achieving a HAI Titer of Greater Than or Equal to 40 After Dose 240 Participants
Secondary

Number of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 After Dose 1.

Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group one month after receipt of the first dose of vaccine.

Time frame: Approximately Day 28

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 After Dose 1.26 Participants
H5 HA IMNumber of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 After Dose 1.29 Participants
Secondary

Number of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 at 7 Months After Dose 1.

Number of participants achieving a serum HAI titer of greater than or equal to 40 against influenza A/H5N1 virus in each vaccine group 7 months after receipt of the first dose of vaccine.

Time frame: Approximately Day 208

ArmMeasureValue (NUMBER)
H5 HA IDNumber of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 at 7 Months After Dose 1.20 Participants
H5 HA IMNumber of Participants Achieving a Serum HAI Titer of Greater Than or Equal to 40 at 7 Months After Dose 1.16 Participants

Source: ClinicalTrials.gov · Data processed: Mar 25, 2026