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Safety and Immunogenicity of PanBlok Influenza Vaccine in Healthy Adults

Phase 2 Observer-Blind, Randomized Trial to Evaluate the Immunogenicity and Safety of PanBlok at Three Dose Levels Adjuvanted With a Stable Oil-in-Water Emulsion Compared With PanBlok Without Adjuvant in Healthy Adults Aged 18 to 49 Years

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01612000
Acronym
PSC25
Enrollment
341
Registered
2012-06-05
Start date
2012-05-31
Completion date
2013-12-31
Last updated
2015-11-25

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

Conditions

Influenza

Keywords

Influenza

Brief summary

The purpose of this study is to investigate the safety and immunogenicity of a recombinant hemagglutinin (rHA) influenza vaccine derived from A/Indonesia/05/2005 (H5N1) administered at 3 dose levels in adjuvanted (SE) rHA formulations and 1 dose levels in an un-adjuvanted rHA formulation.

Detailed description

All currently licensed influenza vaccines in the United States are produced in embryonated hen's eggs. There are several well-recognized disadvantages to the use of eggs as the substrate for influenza vaccine. Eggs require specialized manufacturing facilities and could be difficult to scale up rapidly in response to an emerging need such as a pandemic. It is usually necessary to adapt candidate vaccine viruses for high-yield growth in eggs, a process that can be time consuming, is not always successful, and can select receptor variants that may have suboptimal immunogenicity. In addition, agricultural diseases that affect chicken flocks, and that might be an important issue in a pandemic due to an avian influenza virus strain, could easily disrupt the supply of eggs for vaccine manufacturing. Therefore, development of alternative substrates for influenza vaccine production has been identified as a high-priority objective. One potential alternative method for production of influenza vaccine is expression of the influenza virus hemagglutinin (HA) using recombinant DNA techniques. This alternative avoids dependence on eggs and is very efficient because of the high levels of protein expression under the control of the baculovirus polyhedrin promoter.

Interventions

BIOLOGICALPanBlok

Intramuscular injection

BIOLOGICALrHA adjuvant

Intramuscular injection

Sponsors

Protein Sciences Corporation
Lead SponsorINDUSTRY

Study design

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

Eligibility

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

Inclusion criteria

* Young adults aged 18-49 years * Able to give written informed consent to participate. * Vital signs within normal limits. * The subject must be in good health as determined by targeted physical examination, when necessary, based on medical history. Stable medical condition is defined as: 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. * Comprehensive Metabolic Panel and other tests for the following must fall within normal limits or not exceed a Grade 1 abnormality at screening. Any Grade 1 abnormality must be clinically acceptable to the investigator in the context of other parameters such the subject's medical history. However, this will not apply to an above the upper limit of the normal range for ALT. Subjects with values above the upper limit of the normal range for ALT at the screening visit will not be enrolled. * Complete Blood Count with Cell Differential and urinalysis must fall within normal limits at screening except when clinically acceptable to the investigator in the context of other parameters such the subject's medical history. * Women of child-bearing potential (WOCBP) must have a negative urine pregnancy test within 24 hours preceding receipt of first and second vaccine doses. * WOCBP must use medically acceptable contraception. * Comprehension of the study requirements, expressed availability for the required study period, and ability to attend scheduled visits.

Exclusion criteria

* Previously received an H5N1 influenza vaccine or who plan to receive an H5N1 influenza vaccine while participating in the study * 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 * Medications or treatments that may adversely affect the immune system * An active neoplastic disease or a history of any hematological malignancy. For this criterion, active is defined as having received treatment within the past 5 years. * A long-term use of supraphysiologic doses of oral or parenteral steroids, or high-dose inhaled steroids within the preceding 6 months. * A history of documented autoimmune disease. * Pregnant, nursing mothers or women planning a pregnancy between enrollment and 42 days after randomization * Prior serious reaction to any influenza vaccine * History of Guillain-Barré Syndrome * History of anaphylactic-type reaction to injected vaccines * History of illicit drug use or alcohol abuse in the year preceding the study * Received a seasonal influenza vaccine six months prior to enrollment * Received any licensed inactivated or recombinant vaccine within 2 weeks prior to enrollment or any licensed live vaccine within 1 month prior to enrollment. * Acute illness or fever within three days prior to study enrollment * Participating in a study that involves an experimental agent or have received an experimental agent within 1 month prior to enrollment in this study, or who expect to receive another experimental agent during participation, or intend to donate blood during the 42-day primary study period. * Received or expect to receive immunoglobulin or another blood product within the 3 months prior to enrollment in this study. * An elevated liver function enzyme of ALT at baseline, regardless of the appraisal of clinical significance.

Design outcomes

Primary

MeasureTime frameDescription
The Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.42 DaysImmunogenicity was assessed by measuring the percentage of subjects in each group exhibiting seroconversion on Day 42. The treatment groups that received adjuvanted rHA were evaluated against a non-adjuvanted rHA treatment group for whether they demonstrated seroconversion rates and 95% confidence intervals.
The Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.42 Days

Secondary

MeasureTime frameDescription
Reactogenicity Immediately After Each Injection, Extending to Day 7.7 DaysSolicited events of local and systemic reactogenicity Days 0-7. These events are expected to occur and not considered or recorded as Adverse Events.
Long-term Safety13 MonthsIncidence of Serious Adverse Events (SAEs), New Onset of Chronic Illnesses (NOCIs) and Adverse Events of Special Interest (AESIs) over 12 months following vaccination. Study subjects were followed every three months (for one year following Day 42) by telephone and visit for reports of SAEs, NOCIs, and AESIs.

Countries

United States

Participant flow

Participants by arm

ArmCount
PanBlok 15µg in 2% SE
15µg recombinant hemagglutinin in a 2% oil-in-water stable emulsion (rHA adjuvant). 0.5mL intramuscular injection on Day 0 and Day 21 in the deltoid muscle PanBlok: Intramuscular injection rHA adjuvant: Intramuscular injection
84
PanBlok 3.8µg in 2% SE
3.8µg recombinant hemagglutinin in a 2% oil-in-water stable emulsion (rHA adjuvant). 0.5mL intramuscular injection on Day 0 and Day 21 in the deltoid muscle PanBlok: Intramuscular injection rHA adjuvant: Intramuscular injection
86
PanBlok 7.5µg No Adjuvant
7.5µg recombinant hemagglutinin, no adjuvant. 0.5mL intramuscular injection on Day 0 and Day 21 in the deltoid muscle PanBlok: Intramuscular injection
85
PanBlok 7.5µg in 2% SE
7.5µg recombinant hemagglutinin in a 2% oil-in-water stable emulsion (rHA adjuvant). 0.5mL intramuscular injection on Day 0 and Day 21 in the deltoid muscle PanBlok: Intramuscular injection rHA adjuvant: Intramuscular injection
86
Total341

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003
Overall StudyLost to Follow-up6448
Overall StudyPhysician Decision0010
Overall StudyWithdrawal by Subject3122

Baseline characteristics

CharacteristicTotalPanBlok 7.5µg in 2% SEPanBlok 7.5µg No AdjuvantPanBlok 15µg in 2% SEPanBlok 3.8µg in 2% SE
Age, Continuous31 years30 years32 years32 years31 years
Ethnicity (NIH/OMB)
Hispanic or Latino
42 Participants12 Participants12 Participants8 Participants10 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
299 Participants74 Participants73 Participants76 Participants76 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
4 Participants1 Participants2 Participants0 Participants1 Participants
Race (NIH/OMB)
Asian
8 Participants2 Participants1 Participants2 Participants3 Participants
Race (NIH/OMB)
Black or African American
96 Participants25 Participants21 Participants28 Participants22 Participants
Race (NIH/OMB)
More than one race
1 Participants0 Participants1 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
7 Participants0 Participants3 Participants2 Participants2 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants0 Participants1 Participants0 Participants0 Participants
Race (NIH/OMB)
White
224 Participants58 Participants56 Participants52 Participants58 Participants
Region of Enrollment
United States
341 participants86 participants85 participants84 participants86 participants
Sex: Female, Male
Female
207 Participants48 Participants49 Participants52 Participants58 Participants
Sex: Female, Male
Male
134 Participants38 Participants36 Participants32 Participants28 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
— / —— / —— / —— / —
other
Total, other adverse events
22 / 8413 / 8624 / 8516 / 86
serious
Total, serious adverse events
0 / 842 / 861 / 852 / 86

Outcome results

Primary

The Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.

Time frame: 42 Days

Population: All subjects who received both doses of study vaccine and had pre- and post-immunization immunogenicity data for the time period summarized.

ArmMeasureValue (GEOMETRIC_MEAN)
PanBlok 15µg in 2% SEThe Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.121.7 titer
PanBlok 3.8µg in 2% SEThe Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.76.1 titer
PanBlok 7.5µg No AdjuvantThe Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.7.1 titer
PanBlok 7.5µg in 2% SEThe Difference in Geometric Mean Titer Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.77.5 titer
Primary

The Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.

Immunogenicity was assessed by measuring the percentage of subjects in each group exhibiting seroconversion on Day 42. The treatment groups that received adjuvanted rHA were evaluated against a non-adjuvanted rHA treatment group for whether they demonstrated seroconversion rates and 95% confidence intervals.

Time frame: 42 Days

Population: All subjects who received both doses of study vaccine and had pre- and post-immunization immunogenicity data for the time period summarized.

ArmMeasureValue (NUMBER)
PanBlok 15µg in 2% SEThe Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.83 percentage of participants
PanBlok 3.8µg in 2% SEThe Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.70 percentage of participants
PanBlok 7.5µg No AdjuvantThe Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.9 percentage of participants
PanBlok 7.5µg in 2% SEThe Difference in Seroconversion/Immunogenicity Between rHA Formulated in an oil-in- Water Adjuvant (SE) Compared to a rHA Antigen Alone.76 percentage of participants
Secondary

Long-term Safety

Incidence of Serious Adverse Events (SAEs), New Onset of Chronic Illnesses (NOCIs) and Adverse Events of Special Interest (AESIs) over 12 months following vaccination. Study subjects were followed every three months (for one year following Day 42) by telephone and visit for reports of SAEs, NOCIs, and AESIs.

Time frame: 13 Months

Population: All randomized subjects who received at least one dose of study vaccine and provided any safety data following vaccination.

ArmMeasureGroupValue (NUMBER)
PanBlok 15µg in 2% SELong-term SafetySAEs0 participants
PanBlok 15µg in 2% SELong-term SafetyAESIs0 participants
PanBlok 15µg in 2% SELong-term SafetyNOCIs0 participants
PanBlok 3.8µg in 2% SELong-term SafetySAEs2 participants
PanBlok 3.8µg in 2% SELong-term SafetyAESIs0 participants
PanBlok 3.8µg in 2% SELong-term SafetyNOCIs0 participants
PanBlok 7.5µg No AdjuvantLong-term SafetySAEs1 participants
PanBlok 7.5µg No AdjuvantLong-term SafetyNOCIs0 participants
PanBlok 7.5µg No AdjuvantLong-term SafetyAESIs0 participants
PanBlok 7.5µg in 2% SELong-term SafetySAEs2 participants
PanBlok 7.5µg in 2% SELong-term SafetyAESIs0 participants
PanBlok 7.5µg in 2% SELong-term SafetyNOCIs0 participants
Secondary

Reactogenicity Immediately After Each Injection, Extending to Day 7.

Solicited events of local and systemic reactogenicity Days 0-7. These events are expected to occur and not considered or recorded as Adverse Events.

Time frame: 7 Days

Population: All randomized subjects who received at least one dose of study vaccine and provided any safety data following vaccination.

ArmMeasureGroupValue (NUMBER)
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Nausea/Vomiting1 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Arthralgia4 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site erythema0 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site tenderness47 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Myalgia11 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Chills3 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Fatigue6 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Elevated temperature0 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Headache8 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site pain34 participants
PanBlok 15µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Diarrhea4 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Fatigue9 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Nausea/Vomiting6 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Elevated temperature0 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Diarrhea4 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Chills0 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site erythema1 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site tenderness52 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Arthralgia2 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Myalgia17 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Headache19 participants
PanBlok 3.8µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site pain34 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site pain6 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Elevated temperature0 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Fatigue9 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Chills2 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Myalgia7 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Headache13 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Nausea/Vomiting8 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Diarrhea7 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site tenderness8 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site erythema1 participants
PanBlok 7.5µg No AdjuvantReactogenicity Immediately After Each Injection, Extending to Day 7.Arthralgia4 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Myalgia13 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site pain32 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Arthralgia4 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Chills3 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site erythema2 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Injection site tenderness46 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Fatigue9 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Elevated temperature0 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Diarrhea3 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Nausea/Vomiting3 participants
PanBlok 7.5µg in 2% SEReactogenicity Immediately After Each Injection, Extending to Day 7.Headache8 participants

Source: ClinicalTrials.gov · Data processed: Mar 11, 2026