Persistence of the Immune Response After Immunisation With Ebola Virus Vaccines

Ebola Virus Disease Clinical Trial

— PRISM  

Official title:

Evaluating the Long Term Immunogenicity of Ebola Virus Vaccines Ad26-ZEBOV, MVA-BN-Filo and rVSV-ZEBOV

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03140774
• Other study ID #: OVG2016/04
• Status: Completed
• Start date: May 17, 2017
• Est. completion date: July 10, 2020

Study information

• Verified date: December 2019
• Source: University of Oxford
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The aim of this study is to investigate the persistence of the vaccine induced immune response between 24 - 60 months following primary vaccination.

The study consists of three cohorts:

Cohort 1: volunteers from the Phase 1 study of the various prime/boost regimes with two viral vectored Ebola vaccines: Ad26-ZEBOV and MVA-BN-Filo vaccines

Cohort 2: volunteers who have been vaccinated previously with Ebola vaccine r-VSV-ZEBOV

Cohort 3: volunteers from the Phase 2 study of 3 prime/boost regimes with Ad26.ZEBOV and MVA-BN-Filo vaccines (VAC52150EBL2001: EVOLVE).

Description:

The Ebola Virus Disease (EVD), is caused by the viruses belonging to the genus Ebola virus. The disease occurs in sporadic outbreaks in the endemic zones of Africa and results in high mortality. During an outbreak, human to human to transmission occurs by contact with the body fluids of an infected individual. In the inter-endemic period the disease is zoonotically sustained in the environment. Prevention or control of future endemic outbreaks in the high risk areas of Africa will require effective preventative strategies including immunisation.

Cohort 1:

The Phase 1 study with the multiple heterologous prime boost regimes of the Ad26-ZEBOV and the MVA-BN-Filo vaccines demonstrated a substantive immunogenicity and safety of the vaccines. A combined immune response of humoral and cellular immunity was observed in the study participants. Furthermore, persistence of the immune response was evident at one year following the primary vaccination. It is not known whether the immune response persists beyond this time point. The duration of the immunological response is important as it will inform the clinical utility of the vaccines and whether or not additional booster dosage will be required and if so, at what interval.

In this study we will invite the 56 participants from the Phase 1 study at two time points:

24 - 30 months and 36 - 48 months after receiving the primary vaccination. Following consenting and enrolment into the study, the participants will undergo a blood test. We will assess the humoral immunity by estimating the level of binding antibody to the Ebola virus envelope glycoprotein. Cellular immunity will be assessed by estimating the functional CD4+ and the CD8+ T cells secreting the pro-inflammatory cytokines. We will undertake this assessment by intracellular staining of the peripheral blood mononuclear cells (PBMC) and using flowcytometry technique to identify the positively stained cells. A second assessment of the cellular immunity will be carried out by an in-house ELISpot technique subject to availability of additional funding.

Cohort 2:

In October 2015, contacts of a laboratory-confirmed case of Ebola virus diseases (EVD) in the U.K. were given the rVSV-EBOV vaccine as a part of clinical preventative care. Subsequently, these recipients of the rVSV-EBOV vaccine were enrolled and followed up for safety and immune response until one year post vaccination in the Glasgow Ebola Vaccine Follow-up Study (REC reference 15/WS/0251). The duration of persistence of the immune response to rVSV-EBOV beyond 360 days is unknown and may impact on the use of the vaccine in any future Ebola outbreaks. This study provides an opportunity to study the immune response beyond 1 year from the prime vaccination and to compare those results with the response to MVA-BN-Filo and Ad26-ZEBOV vaccines. This study will also allow for a further period of safety follow-up for this cohort.

Twenty-six individuals were vaccinated with the r-VSV-EBOV Ebola vaccine in Glasgow following possible exposure to a patient with confirmed Ebola virus disease as a part of preventative clinical care. All 26 individuals will be invited to take part in this study.

Cohort 3:

This cohort consists of participants from the Phase 2 study of 3 prime/boost regimes with Ad26.ZEBOV and MVA-BN-Filo vaccines (VAC52150EBL2001: EVOLVE). This was a randomized, observer-blind, placebo-controlled, parallel-group, multicentre, Phase 2 study to evaluate the safety, tolerability and immunogenicity of 3 heterologous prime-boost regimens which differed in the timing of the boost vaccination. The dose of each study vaccine (Ad26.ZEBOV, MVA-BN-Filo or placebo) and the sequence of vaccination were identical in each group. The prime/boost regimens were commenced in July 2015 and completed in February 2016.

Recruitment of participants in Group 1 (unblinded) of EVOLVE into the PRISM study can commence once all approvals are in place. However, for participants in Group 2 (blinded) of the EVOLVE study, recruitment and enrolment will not commence until after EVOLVE has been unblinded (anticipated to occur in Q4 2018 - Q1 2019).

Recruitment information / eligibility

• Status: Completed
• Enrollment: 126
• Est. completion date: July 10, 2020
• Est. primary completion date: July 10, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

Inclusion Criteria:

1. Participant is willing and able to give informed consent for participation in the study.

2. Aged 18 years or above.

3. Subject must have received both vaccines in the phase 1 trial (Cohort 1) the r-VSV-ZEBOV vaccine (Cohort 2), or both vaccines in the Phase 2 trial (Cohort 3)

4. Agree to allow his or her General Practitioner and or Consultant if appropriate, to be notified of participation in the study, if required.

Exclusion Criteria:

1. History of malignancy and receipt of immunosuppressive therapy

2. Post organ or stem cell transplantation with or without follow-on immunosuppressive therapy

3. Receipt of adeno virus or MVA virus based vaccine since the Phase 1 or Phase 2 study (Cohort 1 and 3) or since receiving the r-VSV-ZEBOV vaccine (Cohort 2)

4. Chronic or recurrent use of medication which modify host immune response

5. A visit to an Ebola endemic area since the Phase 1 or Phase 2 study (Cohort 1 and 3) or since receiving the r-VSV-ZEBOV vaccine (Cohort 2)

6. Any contraindication to venepuncture, as determined by clinical judgement

Related Conditions & MeSH terms

• Ebola Virus Disease
• Hemorrhagic Fever, Ebola
• Virus Diseases

Intervention

Biological:
• Previously exposed to Ebola vaccine
Exposure of interest: participants must have had one or more previous Ebola vaccines, Ad26.ZEBOV , MVA-BN-Filo or r-VSV-ZEBOV to enter the study.

Locations

Country	Name	City	State
United Kingdom	MRC - University of Glasgow Centre for Virus Research	Glasgow
United Kingdom	Oxford Vaccine Group, University of Oxford	Oxford

Sponsors (2)

Lead Sponsor	Collaborator
University of Oxford	University of Glasgow

Country where clinical trial is conducted

United Kingdom, 

References & Publications (2)

Milligan ID, Gibani MM, Sewell R, Clutterbuck EA, Campbell D, Plested E, Nuthall E, Voysey M, Silva-Reyes L, McElrath MJ, De Rosa SC, Frahm N, Cohen KW, Shukarev G, Orzabal N, van Duijnhoven W, Truyers C, Bachmayer N, Splinter D, Samy N, Pau MG, Schuitemaker H, Luhn K, Callendret B, Van Hoof J, Douoguih M, Ewer K, Angus B, Pollard AJ, Snape MD. Safety and Immunogenicity of Novel Adenovirus Type 26- and Modified Vaccinia Ankara-Vectored Ebola Vaccines: A Randomized Clinical Trial. JAMA. 2016 Apr 19;315(15):1610-23. doi: 10.1001/jama.2016.4218. — View Citation

Winslow RL, Milligan ID, Voysey M, Luhn K, Shukarev G, Douoguih M, Snape MD. Immune Responses to Novel Adenovirus Type 26 and Modified Vaccinia Virus Ankara-Vectored Ebola Vaccines at 1 Year. JAMA. 2017 Mar 14;317(10):1075-1077. doi: 10.1001/jama.2016.20644. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Cellular Immunity by alternative method	Interferon-gamma (INF-gamma) release by Ebola GP specific activated T cells as measured by ELISpot	24 to 60 months following the primary vaccination
Primary	Humoral Immunity	Binding antibody to the Ebola viral glycoprotein (GP) antigen assessed by ELISA	24 to 60 months following the primary vaccination
Secondary	Cellular Immunity	Pro-inflammatory cytokine response of T cells, by using intracellular staining technique and multicolour flow cytometer	24 to 60 months following the primary vaccination

External Links

•   Oxford Vaccine Group homepage