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A Safety and Efficacy Study of Concomitant Administration of ChAd63/MVA ME-TRAP + RTS,S

2. prosince 2015 aktualizováno: University of Oxford

A Phase I/IIa Sporozoite Challenge Study to Assess the Safety and Protective Efficacy of Concomitant Administration of the Combination Malaria Vaccine Candidate Regimen of RTS,S/AS01¬B + ChAd63 and MVA Encoding ME-TRAP and Also RTS,S/AS01B Alone

The purpose of this study is to assess two types of new malaria vaccines in different combinations. The study will enable us to assess:

  1. The ability of the vaccines to prevent malaria infection.
  2. The safety of the vaccines in healthy participants.
  3. The response of the human immune system to the vaccines.

We will do this by giving 48 participants three sets of vaccinations over 8 weeks, then exposing them to malaria infection by allowing mosquitoes infected with malaria to bite under carefully regulated conditions. We will follow participants closely to observe if and when they develop malaria. If the vaccine combination provides some protection against malaria, participants will take longer to develop malaria than usual or will not develop malaria at all. We will also recruit 4 individuals to be control subjects - these participants won't receive any vaccinations but will be challenged with malaria.

Vaccinated volunteers who do not develop malaria infection in the blood after being infected with malaria by mosquito bite the first time may be invited back to be again infected with malaria in a repeat challenge experiment. This would happen approximately 5-7 months after the first challenge. The purpose of this second challenge will be to see how long the protection of the investigational vaccine against malaria lasts.

Přehled studie

Typ studie

Intervenční

Zápis (Aktuální)

48

Fáze

  • Fáze 2
  • Fáze 1

Kontakty a umístění

Tato část poskytuje kontaktní údaje pro ty, kteří studii provádějí, a informace o tom, kde se tato studie provádí.

Studijní místa

      • London, Spojené království, W12 0HS
        • NIHR/Wellcome Trust Imperial CRF, Hammersmith Hospital, Imperial College NHS Trust
    • Hampshire
      • Southampton, Hampshire, Spojené království, SO16 6YD
        • NIHR WTCRF, University Hospital Southampton NHS Foundation Trust
    • Oxfordshire
      • Oxford, Oxfordshire, Spojené království, OX3 7LE
        • Centre for Clinical Vaccinology and Tropical Medicine, University of Oxford
    • Surrey
      • Guildford, Surrey, Spojené království, GU2 7XP
        • Surrey Clinical Research Centre, University of Surrey

Kritéria účasti

Výzkumníci hledají lidi, kteří odpovídají určitému popisu, kterému se říká kritéria způsobilosti. Některé příklady těchto kritérií jsou celkový zdravotní stav osoby nebo předchozí léčba.

Kritéria způsobilosti

Věk způsobilý ke studiu

18 let až 45 let (Dospělý)

Přijímá zdravé dobrovolníky

Ano

Pohlaví způsobilá ke studiu

Všechno

Popis

Inclusion Criteria:

  • Healthy adults aged 18 to 45 years.
  • Able and willing (in the Investigator's opinion) to comply with all study requirements.
  • Willing to allow the investigators to discuss the volunteer's medical history with their General Practitioner.
  • Women only: Must practice continuous effective contraception for the duration of the study.
  • Agreement to refrain from blood donation during the course of the study and for at least 3 years after the end of their involvement in the study.
  • Written informed consent to participate in the trial.
  • Reachable (24/7) by mobile phone during the period between Controlled Human Malaria Infection (CHMI) and completion of antimalarial treatment.
  • Willingness to take a curative anti-malaria regimen following CHMI.
  • For volunteers not living in Oxford: agreement to stay in a hotel room close to the trial centre during a part of the study (from at least day 6.5 post mosquito bite until anti-malarial treatment is completed).
  • Answer all questions on the informed consent quiz correctly.

Exclusion Criteria:

  • History of clinical malaria (any species).
  • Travel to a malaria endemic region during the study period or within the preceding six months with significant risk of malaria exposure.
  • Use of systemic antibiotics with known antimalarial activity within 30 days of CHMI (e.g. trimethoprim-sulfamethoxazole, doxycycline, tetracycline, clindamycin, erythromycin, fluoroquinolones and azithromycin)
  • Receipt of an investigational product in the 30 days preceding enrolment, or planned receipt during the study period.
  • Prior receipt of an investigational malaria vaccine or any other investigational vaccine likely to impact on interpretation of the trial data. If any volunteers in Group 1-4 undergo rechallenge, this exclusion criterion does not extend to the vaccines previously received in this trial
  • Any confirmed or suspected immunosuppressive or immunodeficient state, including HIV infection; asplenia; recurrent, severe infections and chronic (more than 14 days) immunosuppressant medication within the past 6 months (inhaled and topical steroids are allowed).
  • Use of immunoglobulins or blood products within 3 months prior to enrolment.
  • History of allergic disease or reactions likely to be exacerbated by any component of the vaccine (e.g. egg products, Kathon) or malaria infection.
  • Any history of anaphylaxis post vaccination.
  • History of clinically significant contact dermatitis.
  • History of sickle cell anaemia, sickle cell trait, thalassaemia or thalassaemia trait or any haematological condition that could affect susceptibility to malaria infection.
  • Pregnancy, lactation or intention to become pregnant during the study.
  • Use of medications known to cause prolongation of the QT interval and existing contraindication to the use of Malarone
  • Use of medications known to have a potentially clinically significant interaction with Riamet and Malarone
  • Any clinical condition known to prolong the QT interval
  • History of cardiac arrhythmia, including clinically relevant bradycardia
  • Disturbances of electrolyte balance, eg, hypokalaemia or hypomagnesaemia
  • Family history of congenital QT prolongation or sudden death
  • Contraindications to the use of all three proposed anti-malarial medications; Riamet, Malarone and Chloroquine.
  • History of cancer (except basal cell carcinoma of the skin and cervical carcinoma in situ).
  • History of serious psychiatric condition that may affect participation in the study.
  • Any other serious chronic illness requiring hospital specialist supervision.
  • Suspected or known current alcohol abuse as defined by an alcohol intake of greater than 42 standard UK units every week.
  • Suspected or known injecting drug abuse in the 5 years preceding enrolment.
  • Hepatitis B surface antigen (HBsAg) detected in serum.
  • Seropositive for hepatitis C virus (antibodies to HCV) at screening (unless has taken part in a prior hepatitis C vaccine study with confirmed negative HCV antibodies prior to participation in that study, and negative HCV RNA PCR at screening for this study).
  • An estimated, ten year risk of fatal cardiovascular disease of ≥5%, as estimated by the Systematic Coronary Risk Evaluation (SCORE) system.59
  • Positive family history in 1st and 2nd degree relatives <50 years old for cardiac disease.
  • Volunteers unable to be closely followed for social, geographic or psychological reasons.
  • Any clinically significant abnormal finding on biochemistry or haematology blood tests, urinalysis or clinical examination. In the event of abnormal test results, confirmatory repeat tests will be requested.
  • Any other significant disease, disorder, or finding which may significantly increase the risk to the volunteer because of participation in the study, affect the ability of the volunteer to participate in the study or impair interpretation of the study data.

Studijní plán

Tato část poskytuje podrobnosti o studijním plánu, včetně toho, jak je studie navržena a co studie měří.

Jak je studie koncipována?

Detaily designu

  • Primární účel: Prevence
  • Přidělení: Randomizované
  • Intervenční model: Paralelní přiřazení
  • Maskování: Žádné (otevřený štítek)

Zbraně a zásahy

Skupina účastníků / Arm
Intervence / Léčba
Aktivní komparátor: Group 1
Week 0: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01), Week 4: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01), Week 8: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01), Week 11: Controlled Human Malaria Infection (CHMI), Week 31-39: Repeat CHMI of sterilely protected volunteers.
Aktivní komparátor: Group 2
Week 0: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01), Week 4: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01), Week 8: RTS,S/AS01B (10mcg of RTS,S and 1/5 of the standard dose of AS01), Week 11: Controlled Human Malaria Infection (CHMI), Week 31-39: Repeat CHMI of sterilely protected volunteers.
Aktivní komparátor: Group 3
Week 0: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01) & ChAd63 ME-TRAP (5 x 10^10 vp), Week 4: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01) & MVA ME-TRAP (2 x 10^8 pfu), Week 8: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01) & MVA ME-TRAP (2 x 10^8 pfu), Week 11: Controlled Human Malaria Infection (CHMI), Week 31-39: Repeat CHMI of sterilely protected volunteers.
Aktivní komparátor: Group 4
Week 0: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01) & ChAd63 ME-TRAP (5 x 10^10 vp), Week 4: RTS,S/AS01B (50mcg of RTS,S and standard adult dose of AS01) & MVA ME-TRAP (2 x 10^8 pfu), Week 8: RTS,S/AS01B (10mcg of RTS,S and 1/5 of the standard dose of AS01) & MVA ME-TRAP (2 x 10^8 pfu), Week 11: Controlled Human Malaria Infection (CHMI), Week 31-39: Repeat CHMI of sterilely protected volunteers.
Žádný zásah: Group 5
Week 11: Controlled Human Malaria Infection
Žádný zásah: Group 6
Week 31-39: Controlled Human Malaria Infection

Co je měření studie?

Primární výstupní opatření

Měření výsledku
Popis opatření
Časové okno
Efficacy of a combination immunization regimen with ChAd63/MVA ME-TRAP given concomitantly with RTS,S/AS01B against malaria sporozoite challenge.
Časové okno: 6 months
Use statistical analysis to compare number of completely protected individuals (those who do not, by Day 23 following sporozoite challenge, develop blood stage infection measured by occurrence of P. falciparum parasitemia, assessed by blood slide)
6 months
Safety of a combination immunization regimen with ChAd63/MVA ME-TRAP given concomitantly with RTS,S/AS01B against malaria sporozoite challenge.
Časové okno: 6 months
Occurrence of solicited and unsolicited adverse events will be monitored. Solicited and unsolicited AE data will be collected at each clinic visit. It will be collected from diary cards, clinical review, clinical examination (including observations) and laboratory results. This AE data will be tabulated and frequency, duration and severity of AEs compared between groups.
6 months

Sekundární výstupní opatření

Měření výsledku
Popis opatření
Časové okno
Immunogenicity generated in malaria naïve individuals of two different dosing regimens of RTS,S/AS01B given concomitantly with ChAd63/MVA ME-TRAP, and of RTS,S/AS01B alone at either full standard dose or with a reduced third dose.
Časové okno: 6 months
To document immunogenicity measures, capturing humoral and cellular immune responses to both ChAd63/MVA ME-TRAP and RTS,S as follows: Anti-CS (RT, C-term, full-length), anti-HBs, and anti-ME-TRAP antibody titers; frequency of CS-specific, HBs-specific, and TRAP and ME specific T cells; ChAd63 neutralizing antibody titers; avidity index of anti-CS antibodies. To undertake exploratory analysis of the correlation of these measures with vaccine efficacy. To, furthermore, undertake an exploratory analysis of transcriptomic correlates of vaccine immunogenicity and efficacy. This may be undertaken by microarray analysis or RNA sequencing or both techniques.
6 months

Další výstupní opatření

Měření výsledku
Popis opatření
Časové okno
Long term protective efficacy of a combination immunization regimen with ChAd63/MVA ME-TRAP given concomitantly with RTS,S/AS01B
Časové okno: 12 months
Long term efficacy of the Group 1, 2, 3 and 4 vaccination regimens will be assessed by re-challenging any sterilely protected individuals at 5 - 7 months after the first CHMI and comparing the number of re-challengees who develop blood stage infection, and the time between CHMI and blood stage infection, with unvaccinated controls.
12 months

Spolupracovníci a vyšetřovatelé

Zde najdete lidi a organizace zapojené do této studie.

Vyšetřovatelé

  • Vrchní vyšetřovatel: Adrian VS Hill, University of Oxford

Termíny studijních záznamů

Tato data sledují průběh záznamů studie a předkládání souhrnných výsledků na ClinicalTrials.gov. Záznamy ze studií a hlášené výsledky jsou před zveřejněním na veřejné webové stránce přezkoumány Národní lékařskou knihovnou (NLM), aby se ujistily, že splňují specifické standardy kontroly kvality.

Hlavní termíny studia

Začátek studia

1. ledna 2015

Primární dokončení (Aktuální)

1. října 2015

Dokončení studie (Aktuální)

1. října 2015

Termíny zápisu do studia

První předloženo

25. září 2014

První předloženo, které splnilo kritéria kontroly kvality

25. září 2014

První zveřejněno (Odhad)

30. září 2014

Aktualizace studijních záznamů

Poslední zveřejněná aktualizace (Odhad)

3. prosince 2015

Odeslaná poslední aktualizace, která splnila kritéria kontroly kvality

2. prosince 2015

Naposledy ověřeno

1. prosince 2015

Více informací

Termíny související s touto studií

Další identifikační čísla studie

  • VAC059
  • 2014-001301-40 (Číslo EudraCT)

Tyto informace byly beze změn načteny přímo z webu clinicaltrials.gov. Máte-li jakékoli požadavky na změnu, odstranění nebo aktualizaci podrobností studie, kontaktujte prosím register@clinicaltrials.gov. Jakmile bude změna implementována na clinicaltrials.gov, bude automaticky aktualizována i na našem webu .

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