Virus, ZikaPhase 1NCT03343626

Safety, Immunogenicity, and Dose Ranging Study of Inactivated Zika Virus Vaccine in Healthy Participants

A Phase 1 study testing PIZV in people with Virus, Zika and Zika Virus Disease, run by Takeda at 9 sites in 2 countries.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record

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Trial summary

Who is it for?: Ages 18 to 49 yearsHealthy volunteers can take part
Conditions the study is for: Virus, Zika, Zika Virus Disease, Flavivirus Infections
What is being tested?: PIZV
Type of treatment: Vaccines, Injection or infusion
Could I receive a placebo?: Yes, some participants may receive a placebo
How many people: 271 participants
Where: 9 sitesin 2 countries
Study dates: 13 Nov 2017to 24 Nov 2020
Phase: Phase 1
Are there results?: Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

Ages 18 to 49 years
All sexes
Healthy volunteers accepted
Adult

Who may be able to join

Participants who are in good health at the time of entry into the trial as determined by medical history, physical examination (including vital signs) and eligibility screening tests (hematology, biochemistry and urinalysis) and clinical judgment of the investigator. Vital signs must be within normal limits (ie, below Grade 1 as specified in the Food and Drug Administration [FDA] Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers). Screening tests must be within normal limits or not be above Grade 1 as defined in the FDA Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers.
Participants who can comply with trial procedures and are available for the duration of follow-up.
All female participants must be willing to undergo serum beta human chorionic gonadotropin (B-hCG) pregnancy test and must test negative by urine pregnancy test prior to each study vaccination.

Who cannot join

Participants and participants' partners with confirmed Zika virus (ZIKV) infection by self-report.
Traveling to flavivirus endemic countries or flavivirus endemic regions of the United States (US) or US territories*, within 4 weeks prior to screening or planned travel through to Visit 6 (applicable only to participants to be enrolled into the flavivirus naïve cohort).
Centers for Disease Control and Prevention (CDC) website define the information about the flavivirus endemic countries and US regions and territories.
Known hypersensitivity or allergy to any of the vaccine candidate components (including excipients of the investigational vaccine or placebo).
Has any history of progressive or severe neurologic disorder, seizure disorder or neuro-inflammatory disease (example, Guillain-Barré syndrome).
Known or suspected impairment/alteration of immune function, including:

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Chronic use of oral steroids (equivalent to 20 milligram per day [mg/day] prednisone greater than or equal to [>=] 12 weeks / >= 2 milligram per kilogram [mg/kg] body weight / day prednisone >= 2 weeks) within 60 days prior to Day 1 (use of inhaled, intranasal, or topical corticosteroids is allowed).
Receipt of parenteral steroids (equivalent to 20 mg/day prednisone >= 12 weeks / >= 2 mg/kg body weight / day prednisone >= 2 weeks) within 60 days prior to Day 1.
Receipt of immunostimulants within 60 days prior to Day 1.
Receipt of parenteral, epidural or intra-articular immunoglobulin preparation, blood products, and/or plasma derived products within 3 months prior to Day 1 or planned during the full length of the trial. In addition, participants must be advised not to donate blood during the study period.
Known Human Immunodeficiency Virus (HIV) infection or HIV-related disease.
Genetic immunodeficiency.
Has known current or chronic hepatitis B and/or hepatitis C infections.
Has abnormalities of spleen or thymic function.
Has a known bleeding diathesis, or any condition that may be associated with a prolonged bleeding time.
Individuals participating in any clinical trial with another investigational product, including ZIKV vaccine clinical trial within 30 days prior to first trial visit or intent to participate in another clinical trial at any time during the conduct of this trial.
Individuals who received any other vaccines within 14 days (for inactivated vaccines) or 28 days (for live vaccines) prior to enrollment in this trial or who are planning to receive any vaccine within 28 days of investigational vaccine/placebo administration.
Female participants who are pregnant or breastfeeding, or are planning to become pregnant.
Any positive or indeterminate pregnancy test.
If female participant of childbearing potential, sexually active, and who has not used any of the "acceptable contraceptive methods" for at least 2 months prior to trial entry:
"Of childbearing potential" is defined as status post onset of menarche and not meeting any of the following conditions: menopausal for at least 2 years without any other alternative medical cause (as confirmed by a healthcare professional), status after bilateral tubal ligation for at least 1 year, status after bilateral oophorectomy, or status after hysterectomy.
Acceptable birth control methods are defined as one or more of the following:
Hormonal contraceptive (such as oral, injection, transdermal patch, implant, cervical ring).
Barrier (condom with spermicide or diaphragm with spermicide) each and every time during intercourse.
Intrauterine device.
Monogamous relationship with vasectomized partner. Partner must have been vasectomized for at least six months prior to the participants' trial entry.
If female participant of childbearing potential and sexually active, refusal to use an "acceptable contraceptive method" from trial entry through 2 months after the last dose of investigational vaccine/placebo. In addition female participants of childbearing potential must be advised not to donate ova during this period.
To avoid sexual transmission of ZIKV from natural exposure: Refusal to use latex condoms correctly and consistently by sexually active participants even if other contraceptive measures are used from signing the informed consent form (ICF) through the end of the trial. Male participants must be advised not to donate sperm during this period.

Trial locations and contacts

9 sites in 2 countries.

Country

City, postcode or hospital

9 sites in 2 countries

United States7 sites

Tekton Research
Austin, Texas, 78745
Clinical Research of South Florida
Coral Gables, Florida, 33134
Regional Clinical Research Inc.
Endwell, New York, 13760
Johnson County Clin-Trials
Lenexa, Kansas, 66219
Miami Research Associates
Miami, Florida, 33143
AppleMed Research
Miami, Florida, 33155
Rochester Clinical Research
Rochester, New York, 14609

Other trials in United States

Puerto Rico2 sites

Puerto Rico Clinical and Translational Research Consortium
San Juan, PR, 00936
Ponce Medical School Foundation
Santurce, PR, 00909

Other trials in Puerto Rico

About this study

Official title: A Phase 1, Randomized, Observer-Blind, Placebo-Controlled, Safety, Immunogenicity, and Dose Ranging Study of Purified Inactivated Zika Virus Vaccine (PIZV) Candidate in Flavivirus Naïve and Primed Healthy Adults Aged 18 to 49 Years

The purpose of this study is to describe the safety, tolerability and immunogenicity of two doses of purified inactivated Zika virus vaccine (PIZV) given 28 days apart. Three different vaccine doses containing different protein concentrations (2, 5 or 10 microgram [mcg]) each, will be given as 2 dose schedule to flavivirus naive and primed healthy adults. Participants will be followed for 7 days post each dose for tolerability and up to 6 months post dose 2 for safety. Immunogenicity assessment will be performed at 28 days post each dose and 6 months post dose 2. In addition, the selected dose group and control group will be followed till 24 months post dose 2 for safety and persistence of immunity.

Read the detailed description

The vaccine being tested in this study is called PIZV or TAK-426 adjuvanted with aluminum hydroxide. The Zika virus vaccine is being tested to provide safety and immunogenicity data to enable the vaccine to be further developed clinically.

The study will enroll approximately 240 participants. Participants will be randomly assigned (by chance, like flipping a coin) to one of the four groups-which will remain undisclosed to the study observer:

Placebo
PIZV: 2 microgram (mcg) Low Dose
PIZV: 5 mcg Medium Dose
PIZV: 10 mcg High Dose

All participants will be administered either placebo or PIZV by intramuscular (IM) injection into the middle third of the deltoid muscle, preferably in the non-dominant arm on Days 1 (Visit 1) and 29 (Visit 4).

This multi-center trial will be conducted in the United States and Puerto Rico. The overall time to participate in this study is up to 25 months. Participants will make multiple visits to the clinic on Days 1, 8, 29, 36, 57, 211, 393 and will be contacted by telephone on Day 133 (Visit 7) and Day 575 (Visit 9) and also visit the clinic on Day 757 (Visit 11) depending on the study arm, for a final follow-up assessment.

Conditions: Virus, Zika, Zika Virus Disease, Flavivirus Infections, Healthy Participants
Being tested: Placebo, PIZV
Keywords: Drug therapy
Medical subject headings: Zika Virus Infection, Flavivirus Infections

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

PlaceboDrug
Placebo (normal saline (0.9% NaCl) IM injection.
PIZVBiological
Also called TAK-426
Purified inactivated Zika virus vaccine with aluminum hydroxide adjuvant IM injection.

Study groups in NCT03343626
Study group	Role	What they receive
Flavivirus-naïve Cohort: Placebo	Placebo comparator	Placebo injection, intramuscular (IM), once on Day 1 (first dose) and Day 29 (second dose). Receives: Drug: Placebo
Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose)	Experimental	PIZV 0.5 mL, 2 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV
Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose)	Experimental	PIZV 0.5 mL, 5 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV
Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose)	Experimental	PIZV 0.5 mL, 10 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV
Flavivirus-primed Cohort: Placebo	Placebo comparator	Placebo injection, IM, once on Day 1 (first dose) and Day 29 (second dose). Receives: Drug: Placebo
Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose)	Experimental	PIZV 0.5 mL, 2 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV
Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose)	Experimental	PIZV 0.5 mL, 5 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV
Flavivirus-primed Cohort: PIZV 10 mcg (High dose)	Experimental	PIZV 0.5 mL, 10 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose). Receives: Biological: PIZV

What is being measured

The primary outcome is the main question the study is designed to answer.

Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 1 of PIZV or Placebo
Solicited local AEs (at injection site) were collected by participants using diary cards within 7 days after first vaccination and included pain (none, mild: no interference with daily activity, moderate: interference with daily activity with or without treatment and severe: prevents daily activity with or without treatment), erythema (<25 mm, mild: >=25 to- <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm), and swelling and induration (<25 mm, mild: >=25 to <=-50 mm, moderate: >50 to <=100 mm, severe: >100 mm). Only categories for which there was at least 1 participant are reported.
Measured: Within 7 days after Dose 1 (Day 8)
Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 2 of PIZV or Placebo
Solicited local AEs (at injection site) were collected by participants using diary cards within 7 days after first vaccination and included pain (none, mild: no interference with daily activity, moderate: interference with daily activity with or without treatment and severe: prevents daily activity with or without treatment), erythema (<25 mm, mild: >=25 to <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm), and swelling and induration (<25 mm, mild: >=25 to <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm). Only categories for which there was at least 1 participant are reported.
Measured: Within 7 days after Dose 2 (Day 36)
Percentage of Participants With Solicited Systemic Adverse Events (AEs) by Severity Within 7 Days After Dose 1 of PIZV or Placebo
Solicited systemic AEs included fever, headache, fatigue, malaise, arthralgia, and myalgia that occurred within 7 days of first vaccination. Solicited systemic AEs (headache, fatigue, malaise, arthralgia, and myalgia) was graded from 0 to 3 by severity; where 0=None, 1=Mild: No interference with daily activity, 2=Moderate: Interference with daily activity, 3=Severe: Prevents daily activity; A systemic AE of fever (defined as ≥38°C or ≥100.4°F) was graded from 1 to 4 by severity; where 1=Mild: 38.0-38.4°C, 2=Moderate: 38.5-38.9°C, 3=Severe: 39.0-40°C, and 4=Potentially life threatening:>40°C. Only categories for which there was at least 1 participant are reported.
Measured: Within 7 days after Dose 1 (Day 8)
Percentage of Participants With Solicited Systemic AEs by Severity Within 7 Days After Dose 2 of PIZV or Placebo
Solicited systemic AEs included fever, headache, fatigue, malaise, arthralgia, and myalgia that occurred within 7 days of first vaccination. Solicited systemic AEs (headache, fatigue, malaise, arthralgia, and myalgia) was graded from 0 to 3 by severity; where 0=None, 1=Mild: No interference with daily activity, 2=Moderate: Interference with daily activity, 3=Severe: Prevents daily activity; A systemic AE of fever (defined as ≥38°C or ≥100.4°F) was graded from 1 to 4 by severity; where 1=Mild: 38.0-38.4°C, 2=Moderate: 38.5-38.9°C, 3=Severe: 39.0-40°C, and 4=Potentially life threatening:>40°C. Only categories for which there was at least 1 participant are reported.
Measured: Within 7 days after Dose 2 (Day 36)
Percentage of Participants Who Experienced at Least One Non-serious Unsolicited AE Within 28 Days After Dose 1 of PIZV or Placebo
An AE was defined as any untoward medical occurrence in participants administered a trial vaccine; it does not necessarily have to have a causal relationship with trial vaccine administration.
Measured: Within 28 days after Dose 1 (Day 29)
Percentage of Participants Who Experienced at Least One Non-serious Unsolicited AE Within 28 Days After Dose 2 of PIZV or Placebo
An AE was defined as any untoward medical occurrence in a clinical investigation participants administered a trial vaccine; it does not necessarily have to have a causal relationship with trial vaccine administration.
Measured: Within 28 days after Dose 2 (Day 57)
Percentage of Participants Who Experienced at Least One Serious Adverse Event (SAE) Within 28 Days After Dose 1 of PIZV or Placebo
A SAE was defined as any untoward medical occurrence that: 1) results in death, 2) is life-threatening, 3) requires inpatient hospitalization or prolongation of existing hospitalization, 4) results in persistent or significant disability/incapacity, 5) leads to a congenital anomaly/birth defect in the offspring of the participant or 6) is an medically important event that satisfies any of the following: a) May require intervention to prevent items 1 through 5 above. b) May expose the participant to danger, even though the event is not immediately life threatening or fatal or does not result in hospitalization.
Measured: Within 28 days after Dose 1 (Day 29)
Percentage of Participants Who Experienced at Least One SAE Within 28 Days After Dose 2 of PIZV or Placebo
A SAE was defined as any untoward medical occurrence that: 1) results in death, 2) is life-threatening, 3) requires inpatient hospitalization or prolongation of existing hospitalization, 4) results in persistent or significant disability/incapacity, 5) leads to a congenital anomaly/birth defect in the offspring of the participant or 6) is an medically important event that satisfies any of the following: a) May require intervention to prevent items 1 through 5 above. b) May expose the participant to danger, even though the event is not immediately life threatening or fatal or does not result in hospitalization.
Measured: Within 28 days after Dose 2 (Day 57)
Geometric Mean Titers (GMTs) of Neutralizing Antibody for Zika Virus (ZIKV) 28 Days After Dose 2 of PIZV or Placebo
GMTs of neutralizing antibodies for ZIKV were measured by the Zika plaque reduction neutralization test (PRNT) test, by assessing the quantity of neutralizing antibodies that bind ZIKV in the assay. The assay results were reported as titers (reciprocal value of the dilution of the serum from the vaccinated individual that inhibits for 50% the plaque formation).
Measured: 28 days after Dose 2 (Day 57)

Secondary outcomes (6)

Percentage of Participants Who Experienced at Least One SAE During the Study
A SAE was defined as any untoward medical occurrence that: 1) results in death, 2) is life-threatening, 3) requires inpatient hospitalization or prolongation of existing hospitalization, 4) results in persistent or significant disability/incapacity, 5) leads to a congenital anomaly/birth defect in the offspring of the participant or 6) is an medically important event that satisfies any of the following: a) May require intervention to prevent items 1 through 5 above. b) May expose the participant to danger, even though the event is not immediately life threatening or fatal or does not result in hospitalization.
Measured: From day of first vaccination (Day 1) up to end of the study (Day 757)
GMTs of Neutralizing Antibody for ZIKV 28 Days After Dose 1 and 6 Months After Dose 2
GMTs of neutralizing antibodies for ZIKV were measured by Zika PRNT test, by assessing the quantity of neutralizing antibodies that bind ZIKV in the assay. The assay results were reported as titers (reciprocal value of the dilution of the serum from the vaccinated individual that inhibits for 50% the plaque formation).
Measured: 28 days after Dose 1 (Day 29); 6 months after Dose 2 (Day 211)
GMTs of Neutralizing Antibody for ZIKV 12 Months and 24 Months After Dose 2 in Applicable Groups
GMTs of neutralizing antibodies for ZIKV were measured by Zika PRNT test, by assessing the quantity of neutralizing antibodies that bind ZIKV in the assay. The assay results were reported as titers (reciprocal value of the dilution of the serum from the vaccinated individual that inhibits for 50% the plaque formation). As prespecified in the protocol, only data for applicable groups (Placebo and PIZV 10 mcg who were followed beyond Day 211) were analyzed and reported at Days 393 and 757 for Flavivirus-naïve Cohort and Flavivirus-primed Cohort.
Measured: 12 months after Dose 2 (Day 393); 24 months after Dose 2 (Day 757)
Percentage of Participants Seropositive for Neutralizing Antibodies Against PIZV 28 Days After Dose 1, 28 Days After Dose 2, and 6 Months After Dose 2
Seropositive participants were defined as participants with detectable serum antibodies (tested positive at or above limit of detection, LOD) as measured by the neutralization assay.
Measured: 28 days after Dose 1 (Day 29); 28 days after Dose 2 (Day 57); 6 months after Dose 2 (Day 211)
Percentage of Participants Seropositive for PIZV 12 Months and 24 Months After Dose 2 in Applicable Groups
Seropositive participants were defined as participants with detectable serum antibodies (tested positive at or above limit of detection, LOD) as measured by the neutralization assay. As prespecified in the protocol, only data for applicable groups (Placebo and PIZV 10 mcg who were followed beyond Day 211) were analyzed and reported at Days 393 and 757 for Flavivirus-naïve Cohort and Flavivirus-primed Cohort.
Measured: 12 months after Dose 2 (Day 393); 24 months after Dose 2 (Day 757)
Percentage of Participants Seroconverted for PIZV 28 Days Post Dose 1 and 28 Days Post Dose 2
Seroconverted participants were defined as participants at Baseline with detectable post-vaccination serum antibodies (test results are at or above LOD) and seropositive participants at Baseline with a four-fold increase in post-vaccination antibodies from Baseline, as measured by the neutralization assay.
Measured: 28 days after Dose 1 (Day 29); 28 days after Dose 2 (Day 57)

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

13 Nov 201724 Nov 2020

First posted17 Nov 2017
Study start13 Nov 2017
Primary completion28 Dec 2018
Study completion24 Nov 2020

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
Publications (2)Papers the sponsor has linked to this study.
Other trials for Virus, ZikaStudies of the same condition, open and under way.
More trials run by TakedaThe sponsor's other registered studies.
What the trial phases meanHow a treatment moves from first tests in people to approval.

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design

Study type: Interventional
Phase: Phase 1
Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind
Who is masked: Investigator, Outcomes assessor
Enrolment: 271 participants (actual)

IDs, dates and publications

ClinicalTrials.gov ID: NCT03343626
Sponsor's protocol ID: ZIK-101
Other IDs: U1111-1201-5778
Status last verified: Nov 2021
First submitted: 13 Nov 2017
Last updated: 11 Feb 2022
Results posted: Yes, on ClinicalTrials.gov
Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No
Individual data sharing: Yes: Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.

Publications

Acosta CJ, Diaz C, Nordio F, Han HH, Moss KJ, Bohning K, Kumar P, Liu M, Patel H, Pacciarini F, Mwangi V, Walter E, Powell TD, El Sahly HM, Baldwin WR, Santangelo J, Anderson EJ, Dubin G. Persistence of Immunogenicity of a Purified Inactivated Zika Virus Vaccine Candidate in Healthy Adults: 2 Years of Follow-up Compared With Natural Infection. J Infect Dis. 2023 May 29;227(11):1303-1312. doi: 10.1093/infdis/jiac482.
PubMed 36484441
Han HH, Diaz C, Acosta CJ, Liu M, Borkowski A. Safety and immunogenicity of a purified inactivated Zika virus vaccine candidate in healthy adults: an observer-blind, randomised, phase 1 trial. Lancet Infect Dis. 2021 Sep;21(9):1282-1292. doi: 10.1016/S1473-3099(20)30733-7. Epub 2021 May 18.
PubMed 34019802

Want to know more?

The sponsor has not listed a contact. The official record may have more details.

Talk to your doctor first and take this page with you. Only the study team can confirm whether you can join.

Questions to ask the study team

What is the study trying to find out?
What would I need to do, and how often would I visit?
Could I receive a placebo instead of the treatment?
What are the possible risks and benefits for me?
Will it cost me anything? Are travel or time paid for?
Can I keep seeing my own doctor during the study?
What happens when the study ends?

See locations

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The Interest of Systematic Screening for Dengue, Chikungunya, and Zika, in Malaria-negative Return Travelers
Arbovirus Infections
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All Virus, Zika trials

Study at a glance

From the registry record, last updated by the sponsor on 11 Feb 2022. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: A Phase 1, Randomized, Observer-Blind, Placebo-Controlled, Safety, Immunogenicity, and Dose Ranging Study of Purified Inactivated Zika Virus Vaccine (PIZV) Candidate in Flavivirus Naïve and Primed Healthy Adults Aged 18 to 49 Years
ClinicalTrials.gov ID: NCT03343626
Acronym / sponsor ID: ZIK-101
Conditions: Virus, Zika, Zika Virus Disease, Flavivirus Infections, Healthy Participants
Keywords: Drug therapy
Phase: Phase 1
Study type: Interventional
Recruitment status: Completed
Enrolment: 271 participants (actual)
Lead sponsor: TakedaIndustry (pharma, biotech, devices)
Study start: 13 Nov 2017 (actual)
Primary completion: 28 Dec 2018 (actual)
Study completion: 24 Nov 2020 (actual)
First posted: 17 Nov 2017 (actual)
Results: Posted 11 Feb 2022

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Placebo
PIZV: 2 microgram (mcg) Low Dose
PIZV: 5 mcg Medium Dose
PIZV: 10 mcg High Dose

Study design

Primary purpose: Prevention
Allocation: Randomised
Intervention model: Parallel groups
Masking: Double blind (investigator, outcomes assessor)
Number of arms: 8

Arm	Type	Receives
Flavivirus-naïve Cohort: Placebo	Placebo comparator	Drug: PlaceboPlacebo injection, intramuscular (IM), once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 2 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 5 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 10 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-primed Cohort: Placebo	Placebo comparator	Drug: PlaceboPlacebo injection, IM, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 2 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 5 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).
Flavivirus-primed Cohort: PIZV 10 mcg (High dose)	Experimental	Biological: PIZVPIZV 0.5 mL, 10 mcg antigen, IM injection, once on Day 1 (first dose) and Day 29 (second dose).

Who may qualify

Ages: 18 to 49 years
Sex: All
Healthy volunteers: Accepted
Age groups: Adult

Key inclusion criteria (3 listed)

Participants who are in good health at the time of entry into the trial as determined by medical history, physical examination (including vital signs) and eligibility screening tests (hematology, biochemistry and urinalysis) and clinical judgment of the investigator. Vital signs must be within normal limits (ie, below Grade 1 as specified in the Food and Drug Administration [FDA] Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers). Screening tests must be within normal limits or not be above Grade 1 as defined in the FDA Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers.
Participants who can comply with trial procedures and are available for the duration of follow-up.
All female participants must be willing to undergo serum beta human chorionic gonadotropin (B-hCG) pregnancy test and must test negative by urine pregnancy test prior to each study vaccination.

Key exclusion criteria (28 listed)

Participants and participants' partners with confirmed Zika virus (ZIKV) infection by self-report.
Traveling to flavivirus endemic countries or flavivirus endemic regions of the United States (US) or US territories*, within 4 weeks prior to screening or planned travel through to Visit 6 (applicable only to participants to be enrolled into the flavivirus naïve cohort).
Known hypersensitivity or allergy to any of the vaccine candidate components (including excipients of the investigational vaccine or placebo).
Has any history of progressive or severe neurologic disorder, seizure disorder or neuro-inflammatory disease (example, Guillain-Barré syndrome).
Known or suspected impairment/alteration of immune function, including:

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
PlaceboPlacebo (normal saline (0.9% NaCl) IM injection.	Drug	Flavivirus-naïve Cohort: Placebo, Flavivirus-primed Cohort: Placebo
PIZVAlso: TAK-426Purified inactivated Zika virus vaccine with aluminum hydroxide adjuvant IM injection.	Biological	Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose), Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose), Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose), Flavivirus-primed Cohort: PIZV 10 mcg (High dose), Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose), Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose)

Primary outcome

Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 1 of PIZV or Placebo
Time frame: Within 7 days after Dose 1 (Day 8)
Solicited local AEs (at injection site) were collected by participants using diary cards within 7 days after first vaccination and included pain (none, mild: no interference with daily activity, moderate: interference with daily activity with or without treatment and severe: prevents daily activity with or without treatment), erythema (<25 mm, mild: >=25 to- <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm), and swelling and induration (<25 mm, mild: >=25 to <=-50 mm, moderate: >50 to <=100 mm, severe: >100 mm). Only categories for which there was at least 1 participant are reported.
Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 2 of PIZV or Placebo
Time frame: Within 7 days after Dose 2 (Day 36)
Solicited local AEs (at injection site) were collected by participants using diary cards within 7 days after first vaccination and included pain (none, mild: no interference with daily activity, moderate: interference with daily activity with or without treatment and severe: prevents daily activity with or without treatment), erythema (<25 mm, mild: >=25 to <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm), and swelling and induration (<25 mm, mild: >=25 to <=50 mm, moderate: >50 to <=100 mm, severe: >100 mm). Only categories for which there was at least 1 participant are reported.
Percentage of Participants With Solicited Systemic Adverse Events (AEs) by Severity Within 7 Days After Dose 1 of PIZV or Placebo
Time frame: Within 7 days after Dose 1 (Day 8)
Solicited systemic AEs included fever, headache, fatigue, malaise, arthralgia, and myalgia that occurred within 7 days of first vaccination. Solicited systemic AEs (headache, fatigue, malaise, arthralgia, and myalgia) was graded from 0 to 3 by severity; where 0=None, 1=Mild: No interference with daily activity, 2=Moderate: Interference with daily activity, 3=Severe: Prevents daily activity; A systemic AE of fever (defined as ≥38°C or ≥100.4°F) was graded from 1 to 4 by severity; where 1=Mild: 38.0-38.4°C, 2=Moderate: 38.5-38.9°C, 3=Severe: 39.0-40°C, and 4=Potentially life threatening:>40°C. Only categories for which there was at least 1 participant are reported.
Percentage of Participants With Solicited Systemic AEs by Severity Within 7 Days After Dose 2 of PIZV or Placebo
Time frame: Within 7 days after Dose 2 (Day 36)
Solicited systemic AEs included fever, headache, fatigue, malaise, arthralgia, and myalgia that occurred within 7 days of first vaccination. Solicited systemic AEs (headache, fatigue, malaise, arthralgia, and myalgia) was graded from 0 to 3 by severity; where 0=None, 1=Mild: No interference with daily activity, 2=Moderate: Interference with daily activity, 3=Severe: Prevents daily activity; A systemic AE of fever (defined as ≥38°C or ≥100.4°F) was graded from 1 to 4 by severity; where 1=Mild: 38.0-38.4°C, 2=Moderate: 38.5-38.9°C, 3=Severe: 39.0-40°C, and 4=Potentially life threatening:>40°C. Only categories for which there was at least 1 participant are reported.
Percentage of Participants Who Experienced at Least One Non-serious Unsolicited AE Within 28 Days After Dose 1 of PIZV or Placebo
Time frame: Within 28 days after Dose 1 (Day 29)
An AE was defined as any untoward medical occurrence in participants administered a trial vaccine; it does not necessarily have to have a causal relationship with trial vaccine administration.
Percentage of Participants Who Experienced at Least One Non-serious Unsolicited AE Within 28 Days After Dose 2 of PIZV or Placebo
Time frame: Within 28 days after Dose 2 (Day 57)
An AE was defined as any untoward medical occurrence in a clinical investigation participants administered a trial vaccine; it does not necessarily have to have a causal relationship with trial vaccine administration.
Percentage of Participants Who Experienced at Least One Serious Adverse Event (SAE) Within 28 Days After Dose 1 of PIZV or Placebo
Time frame: Within 28 days after Dose 1 (Day 29)
A SAE was defined as any untoward medical occurrence that: 1) results in death, 2) is life-threatening, 3) requires inpatient hospitalization or prolongation of existing hospitalization, 4) results in persistent or significant disability/incapacity, 5) leads to a congenital anomaly/birth defect in the offspring of the participant or 6) is an medically important event that satisfies any of the following: a) May require intervention to prevent items 1 through 5 above. b) May expose the participant to danger, even though the event is not immediately life threatening or fatal or does not result in hospitalization.
Percentage of Participants Who Experienced at Least One SAE Within 28 Days After Dose 2 of PIZV or Placebo
Time frame: Within 28 days after Dose 2 (Day 57)
A SAE was defined as any untoward medical occurrence that: 1) results in death, 2) is life-threatening, 3) requires inpatient hospitalization or prolongation of existing hospitalization, 4) results in persistent or significant disability/incapacity, 5) leads to a congenital anomaly/birth defect in the offspring of the participant or 6) is an medically important event that satisfies any of the following: a) May require intervention to prevent items 1 through 5 above. b) May expose the participant to danger, even though the event is not immediately life threatening or fatal or does not result in hospitalization.
Geometric Mean Titers (GMTs) of Neutralizing Antibody for Zika Virus (ZIKV) 28 Days After Dose 2 of PIZV or Placebo
Time frame: 28 days after Dose 2 (Day 57)
GMTs of neutralizing antibodies for ZIKV were measured by the Zika plaque reduction neutralization test (PRNT) test, by assessing the quantity of neutralizing antibodies that bind ZIKV in the assay. The assay results were reported as titers (reciprocal value of the dilution of the serum from the vaccinated individual that inhibits for 50% the plaque formation).

6 secondary outcomes

Percentage of Participants Who Experienced at Least One SAE During the Study
Time frame: From day of first vaccination (Day 1) up to end of the study (Day 757)
GMTs of Neutralizing Antibody for ZIKV 28 Days After Dose 1 and 6 Months After Dose 2
Time frame: 28 days after Dose 1 (Day 29); 6 months after Dose 2 (Day 211)
GMTs of Neutralizing Antibody for ZIKV 12 Months and 24 Months After Dose 2 in Applicable Groups
Time frame: 12 months after Dose 2 (Day 393); 24 months after Dose 2 (Day 757)
Percentage of Participants Seropositive for Neutralizing Antibodies Against PIZV 28 Days After Dose 1, 28 Days After Dose 2, and 6 Months After Dose 2
Time frame: 28 days after Dose 1 (Day 29); 28 days after Dose 2 (Day 57); 6 months after Dose 2 (Day 211)
Percentage of Participants Seropositive for PIZV 12 Months and 24 Months After Dose 2 in Applicable Groups
Time frame: 12 months after Dose 2 (Day 393); 24 months after Dose 2 (Day 757)
Percentage of Participants Seroconverted for PIZV 28 Days Post Dose 1 and 28 Days Post Dose 2
Time frame: 28 days after Dose 1 (Day 29); 28 days after Dose 2 (Day 57)

Results and safety

Results posted to the registry on 11 Feb 2022, as reported by the sponsor. Figures are copied from the record, not re-analysed. Full results on ClinicalTrials.gov.

Participant flow

Group	Started	Completed
Flavivirus-naïve Cohort: Placebo	31	25
Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose)	31	26
Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose)	31	29
Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose)	32	24
Flavivirus-primed Cohort: Placebo	36	29
Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose)	37	32
Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose)	37	32
Flavivirus-primed Cohort: PIZV 10 mcg (High Dose)	36	25

Primary outcome: Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 1 of PIZV or Placebo

Time frame: Within 7 days after Dose 1 (Day 8). Number. Unit: percentage of participants

Measure	Flavivirus-naïve Cohort: Placebo n = 30	Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose) n = 30	Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose) n = 31	Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose) n = 31	Flavivirus-primed Cohort: Placebo n = 36	Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose) n = 33	Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose) n = 36	Flavivirus-primed Cohort: PIZV 10 mcg (High Dose) n = 35
Pain, Mild	13.3	30.0	32.3	38.7	8.3	33.3	30.6	34.3
Pain, Moderate	0.0	0.0	0.0	0.0	0.0	9.1	8.3	2.9
Pain, Severe	0.0	0.0	0.0	0.0	0.0	3.0	0.0	0.0
Erythema, <25 mm	0.0	0.0	0.0	3.2	5.6	3.0	2.8	0.0
Induration, <25 mm	0.0	0.0	9.7	6.5	0.0	3.0	5.6	0.0
Swelling, <25 mm	0.0	0.0	0.0	0.0	0.0	6.1	5.6	2.9

Population analysed: Safety Analysis Set included all randomized participants who received at least one (1) dose of PIZV or placebo. Overall number of participants are the number of participants with data available for analyses.

Primary outcome: Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 2 of PIZV or Placebo

Time frame: Within 7 days after Dose 2 (Day 36). Number. Unit: percentage of participants

Measure	Flavivirus-naïve Cohort: Placebo n = 28	Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose) n = 27	Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose) n = 30	Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose) n = 30	Flavivirus-primed Cohort: Placebo n = 33	Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose) n = 32	Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose) n = 32	Flavivirus-primed Cohort: PIZV 10 mcg (High Dose) n = 34
Pain, Mild	14.3	29.6	30.0	36.7	18.2	21.9	21.9	20.6
Pain, Moderate	0.0	0.0	6.7	3.3	0.0	0.0	6.3	8.8
Erythema, <25 mm	3.6	0.0	3.3	3.3	0.0	3.1	3.1	2.9
Erythema, Mild	0.0	0.0	0.0	0.0	0.0	3.2	0.0	0.0
Induration, <25 mm	0.0	0.0	3.3	0.0	0.0	0.0	3.1	2.9
Swelling, <25 mm	0.0	0.0	6.7	0.0	0.0	0.0	0.0	5.9
Swelling, Mild	0.0	0.0	0.0	0.0	0.0	3.1	0.0	0.0

Primary outcome: Percentage of Participants With Solicited Systemic Adverse Events (AEs) by Severity Within 7 Days After Dose 1 of PIZV or Placebo

Time frame: Within 7 days after Dose 1 (Day 8). Number. Unit: percentage of participants

Measure	Flavivirus-naïve Cohort: Placebo n = 31	Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose) n = 31	Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose) n = 31	Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose) n = 32	Flavivirus-primed Cohort: Placebo n = 36	Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose) n = 37	Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose) n = 37	Flavivirus-primed Cohort: PIZV 10 mcg (High Dose) n = 36
Fever, Mild	3.3	0.0	0.0	0.0	0.0	0.0	2.8	0.0
Fever, Moderate	0.0	0.0	0.0	3.2	0.0	0.0	0.0	0.0
Headache, Mild	20.0	13.3	19.4	12.9	11.1	12.1	13.9	11.4
Headache, Moderate	13.3	3.3	6.5	0.0	2.8	3.0	5.6	2.9
Headache, Severe	0.0	0.0	0.0	0.0	0.0	0.0	2.8	2.9
Fatigue, Mild	16.7	16.7	16.1	25.8	16.7	6.1	25.0	17.1
Fatigue, Moderate	6.7	6.7	3.2	6.5	8.3	3.0	0.0	0.0
Arthralgia, Mild	3.3	0.0	3.2	6.5	8.3	12.1	11.1	5.7

Population analysed: Safety Analysis Set included all randomized participants who received at least one (1) dose of PIZV or placebo. Number analyzed is the number of participants with data available for analyses in the specific category.

Primary outcome: Percentage of Participants With Solicited Systemic AEs by Severity Within 7 Days After Dose 2 of PIZV or Placebo

Time frame: Within 7 days after Dose 2 (Day 36). Number. Unit: percentage of participants

Measure	Flavivirus-naïve Cohort: Placebo n = 31	Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose) n = 31	Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose) n = 31	Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose) n = 32	Flavivirus-primed Cohort: Placebo n = 36	Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose) n = 37	Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose) n = 37	Flavivirus-primed Cohort: PIZV 10 mcg (High Dose) n = 36
Fever, Mild	3.2	0.0	0.0	0.0	0.0	0.0	0.0	0.0
Fever, Severe	3.2	0.0	0.0	0.0	0.0	0.0	6.4	0.0
Headache, Mild	6.9	14.8	0.0	16.7	6.1	6.3	12.5	2.9
Headache, Moderate	3.4	0.0	3.3	3.3	3.3	0.0	0.0	8.8
Headache, Severe	0.0	0.0	0.0	0.0	0.0	0.0	3.1	0.0
Fatigue, Mild	13.8	11.1	3.3	13.3	9.1	3.1	9.4	11.8
Fatigue, Moderate	6.9	0.0	3.3	3.3	0.0	0.0	3.1	2.9
Arthralgia, Mild	0.0	7.4	0.0	0.0	0.0	9.4	3.1	2.9

6 secondary outcomes are reported in the full results.

Adverse events

Time frame: All Cause Mortality and Serious Adverse Events: From day of first vaccination (Day 1) up to end of the study (Day 757); Non Serious Adverse Events: Up to 28 days (day of vaccination + 27 days) after administration of each vaccine dose on Day 1 and Day 29. Other adverse events reported at 5% frequency or more

Group	Serious adverse events	Other adverse events	Deaths
Flavivirus-naïve Cohort: Placebo	1 of 31 (3.2%)	4 of 31 (12.9%)	0 of 31
Flavivirus-naïve Cohort: PIZV 2 mcg (Low Dose)	1 of 31 (3.2%)	3 of 31 (9.7%)	0 of 31
Flavivirus-naïve Cohort: PIZV 5 mcg (Medium Dose)	0 of 31 (0%)	3 of 31 (9.7%)	0 of 31
Flavivirus-naïve Cohort: PIZV 10 mcg (High Dose)	2 of 32 (6.3%)	4 of 32 (12.5%)	0 of 32
Flavivirus-primed Cohort: Placebo	1 of 36 (2.8%)	5 of 36 (13.9%)	0 of 36
Flavivirus-primed Cohort: PIZV 2 mcg (Low Dose)	2 of 37 (5.4%)	5 of 37 (13.5%)	0 of 37
Flavivirus-primed Cohort: PIZV 5 mcg (Medium Dose)	0 of 37 (0%)	7 of 37 (18.9%)	0 of 37
Flavivirus-primed Cohort: PIZV 10 mcg (High Dose)	4 of 36 (11.1%)	8 of 36 (22.2%)	0 of 36

Loading the posted results from ClinicalTrials.gov…

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 11 Feb 2022.
Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
Derived from this study: PubMed 36484441Acosta CJ, Diaz C, Nordio F, Han HH, Moss KJ, Bohning K, Kumar P, Liu M, Patel H, Pacciarini F, Mwangi V, Walter E, Powell TD, El Sahly HM, Baldwin WR, Santangelo J, Anderson EJ, Dubin G. Persistence of Immunogenicity of a Purified Inactivated Zika Virus Vaccine Candidate in Healthy Adults: 2 Years of Follow-up Compared With Natural Infection. J Infect Dis. 2023 May 29;227(11):1303-1312. doi: 10.1093/infdis/jiac482.
Derived from this study: PubMed 34019802Han HH, Diaz C, Acosta CJ, Liu M, Borkowski A. Safety and immunogenicity of a purified inactivated Zika virus vaccine candidate in healthy adults: an observer-blind, randomised, phase 1 trial. Lancet Infect Dis. 2021 Sep;21(9):1282-1292. doi: 10.1016/S1473-3099(20)30733-7. Epub 2021 May 18.
Individual participant dataSharing planned: Yes. Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.

Medical Director study director

Takeda

9 sites in 2 countries: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 1 study testing PIZV in people with Virus, Zika and Zika Virus Disease, run by Takeda at 9 sites in 2 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 3 inclusion and 28 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 11 Feb 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 9 sites in United States, Puerto Rico. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 11 Feb 2022). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Percentage of Participants With Solicited Local Injection Site Reactions by Severity Within 7 Days After Dose 1 of PIZV or Placebo (time frame: Within 7 days after Dose 1 (Day 8)). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03343626, which also lists 2 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Feb 2022.