Oropouche InfectionOROV-IMMNCT07921641
Characterization of Adaptive Immune Responses to Oropouche Virus (OROV) Infection
An observational study of Oropouche Infection, run by Institut Pasteur.
Trial summary
Oropouche virus (OROV), a re-emerging South American arbovirus causing dengue-like fever and occasional neurological complications, is expanding its circulation towards more densely populated areas in French Guiana, as evidenced by recent cases near Cayenne in 2026. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Oropouche Infection
- What is being tested?
- 20 ml blood sample
- How many people
- 80 participants
- Where
- No sites listed yet
- Study dates
- 30 Nov 2026to 30 Dec 2027
- How long will I take part?
- 1 Day
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
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 years and older
- All sexes
- Adult, Older adult
Study population: The study population lives in French Guiana in 3 different areas (Saül, Trois Sauts, and Cayenne and its surroundings), and eligible individuals (Populations 1 and 3) or those residing in a high-seroprevalence geographic area (Population 2) were identified by the National Reference Center (CNR) for Arboviruses at the Institut Pasteur of French Guiana (IPG) as part of arbovirus virological surveillance in French Guiana.
Who may be able to join
- For all:
- Adults (≥18 years old)
- Willingness to participate in the study after explanation and signing of the informed consent form
- Study population 1:
- Presenting a laboratory-confirmed OROV infection, defined by a positive real-time RT-PCR and/or positive seroneutralization performed as part of the management of and response to the 2020 OROV epidemic in Saül.
- Study population 2:
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- Residing in Trois-Sauts for at least 5 years
- Study population 3:
- Presenting a laboratory-confirmed OROV infection, defined by a positive real-time RT-PCR and/or positive seroneutralization, identified in the Cayenne area and surrounding localities during the study period, as part of the surveillance activities of the CNR for Arboviruses (IPG).
Who cannot join
- For all:
- Pregnant women.
- Individuals presenting with severe chronic pathologies (notably active cancer, primary or secondary immunodeficiency, immunosuppressive treatment, HIV infection, or autoimmune diseases), according to the information declared by the participants.
About this study
Oropouche virus (OROV), a re-emerging South American arbovirus causing dengue-like fever and occasional neurological complications, is expanding its circulation towards more densely populated areas in French Guiana, as evidenced by recent cases near Cayenne in 2026. While animal models indicate that B cell-mediated humoral immunity is critical for viral control, the human antibody response to OROV remains poorly characterized. Despite WHO-led international research efforts, there is currently no vaccine, antiviral treatment, or described human monoclonal antibody against OROV - a major gap that hinders therapeutic and vaccine development. Identifying human neutralizing monoclonal antibodies could offer a promising therapeutic option, particularly for vulnerable populations such as pregnant women.
Read the detailed description
The goal of this project is to characterize the adaptive immune response to OROV infection during the convalescent phase.
The study is based on three complementary populations: (1) 17 adults with confirmed past OROV infection (2020) who will be recontacted for follow-up sampling; (2) 50 adults recruited prospectively from a village with ∼80% seroprevalence, aiming to include at least 20 seropositive individuals for robust analysis of antigen-specific B and T cell responses; and (3) an exploratory cohort of 1 to 10 newly confirmed OROV cases identified during the study period in the Cayenne region, enrolled during the convalescent phase (≥1 month post-diagnosis) to complement the immunological analyses conducted in the first two populations.
A 20 ml blood sample is collected, along with data collection (mainly health data), at the time of enrollment.
The study involves: (1) confirming past OROV infection by detecting OROV-specific polyclonal antibodies in plasma; and (2) characterizing OROV-specific B and T cell responses. Key methodological steps include: isolation of OROV-specific B cells by flow cytometry followed by single-cell culture and stimulation to generate human monoclonal antibodies; screening of secreted mAbs against OROV antigens combined with VDJ sequencing to characterize immunoglobulin repertoires; and structural characterization of neutralizing mAbs using cryo-electron microscopy and nano-imaging to identify conserved epitopes.
- Conditions
- Oropouche Infection
- Being tested
- 20 ml blood sample
- Keywords
- Oropouche virus, Adaptative Immune Response, B cells, Monoclonal antibody discovery
- Medical subject headings
- Bunyaviridae Infections
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
20 ml blood sampleOther
A 20-ml blood sample
| Study group | Role | What they receive |
|---|---|---|
| adults with confirmed past OROV infection (2020) recruited from Saül | Not described Receives: Other: 20 ml blood sample | |
| adults recruited from Trois-Sauts with ∼80% seroprevalence | Not described Receives: Other: 20 ml blood sample | |
| newly confirmed OROV cases identified during the study period in the Cayenne region | Not described Receives: Other: 20 ml blood sample |
What is being measured
The primary outcome is the main question the study is designed to answer.
Characterization of the adaptive immune response to OROV infection during the convalescent phase.
OROV-specific polyclonal antibodies will be detected in participants' plasma to confirm prior infection.
Measured: 12 months
Secondary outcomes (3)
Isolate OROV-specific B cells (recognizing the Gn_Gc antigenic complex) and generate human monoclonal antibodies by single B cell culture.
Isolation of OROV-specific B cells by flow cytometry, followed by culture and stimulation of single B cells to generate and identify human monoclonal antibodies specific to OROV.
Measured: 12 months
Screening of secreted mAbs using OROV antigens and VDJ sequencing to characterize immunoglobulin repertoires.
secreted mAbs using OROV antigens and VDJ sequencing will be screened to characterize immunoglobulin repertoires.
Measured: 12 months
Structural characterization of neutralizing mAbs by cryo-EM and nano-imaging to identify conserved epitopes.
cryo-EM and nano-imaging will be performed on neutralizing mAbs to characterize structurally the mAbs
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Nov 2026
- Study start30 Nov 2026 (estimated)
- Primary completion30 Dec 2027 (estimated)
- Study completion30 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Oropouche InfectionStudies of the same condition, open and under way.
- More trials run by Institut PasteurThe 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
- Observational
- Observational model
- Other
- Time perspective
- Prospective
- Enrolment
- 80 participants (estimated)
- Target duration
- 1 Day
Sponsor and investigators
- Lead sponsor
- Institut Pasteur
- Sponsor type
- Industry (pharma, biotech, devices)
- Collaborators
- CHU Guyane, Institut Pasteur du Cambodge
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07921641
- Sponsor's protocol ID
- 2026-047_OROV-IMM
- Other IDs
- 2026-A01467-44
- Acronym
- OROV-IMM
- Status last verified
- Oct 2026
- First submitted
- 2 Nov 2026
- Last updated
- 6 Nov 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 Nov 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Characterization of Adaptive Immune Responses to Oropouche Virus (OROV) Infection
- ClinicalTrials.gov ID
- NCT07921641
- Acronym / sponsor ID
- OROV-IMM / 2026-047_OROV-IMM
- Conditions
- Oropouche Infection
- Keywords
- Oropouche virus, Adaptative Immune Response, B cells, Monoclonal antibody discovery
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Institut PasteurIndustry (pharma, biotech, devices)
- Collaborators
- CHU Guyane, Institut Pasteur du Cambodge
- Study start
- 30 Nov 2026 (estimated)
- Primary completion
- 30 Dec 2027 (estimated)
- Study completion
- 30 Dec 2027 (estimated)
- First posted
- 6 Nov 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Oropouche virus (OROV), a re-emerging South American arbovirus causing dengue-like fever and occasional neurological complications, is expanding its circulation towards more densely populated areas in French Guiana, as evidenced by recent cases near Cayenne in 2026. While animal models indicate that B cell-mediated humoral immunity is critical for viral control, the human antibody response to OROV remains poorly characterized. Despite WHO-led international research efforts, there is currently no vaccine, antiviral treatment, or described human monoclonal antibody against OROV - a major gap that hinders therapeutic and vaccine development. Identifying human neutralizing monoclonal antibodies could offer a promising therapeutic option, particularly for vulnerable populations such as pregnant women.
Detailed description
The goal of this project is to characterize the adaptive immune response to OROV infection during the convalescent phase.
The study is based on three complementary populations: (1) 17 adults with confirmed past OROV infection (2020) who will be recontacted for follow-up sampling; (2) 50 adults recruited prospectively from a village with ∼80% seroprevalence, aiming to include at least 20 seropositive individuals for robust analysis of antigen-specific B and T cell responses; and (3) an exploratory cohort of 1 to 10 newly confirmed OROV cases identified during the study period in the Cayenne region, enrolled during the convalescent phase (≥1 month post-diagnosis) to complement the immunological analyses conducted in the first two populations.
A 20 ml blood sample is collected, along with data collection (mainly health data), at the time of enrollment.
The study involves: (1) confirming past OROV infection by detecting OROV-specific polyclonal antibodies in plasma; and (2) characterizing OROV-specific B and T cell responses. Key methodological steps include: isolation of OROV-specific B cells by flow cytometry followed by single-cell culture and stimulation to generate human monoclonal antibodies; screening of secreted mAbs against OROV antigens combined with VDJ sequencing to characterize immunoglobulin repertoires; and structural characterization of neutralizing mAbs using cryo-electron microscopy and nano-imaging to identify conserved epitopes.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Target follow-up
- 1 Day
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| adults with confirmed past OROV infection (2020) recruited from Saül | – | Other: 20 ml blood sample |
| adults recruited from Trois-Sauts with ∼80% seroprevalence | – | Other: 20 ml blood sample |
| newly confirmed OROV cases identified during the study period in the Cayenne region | – | Other: 20 ml blood sample |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Age groups
- Adult, Older adult
- Study population
- The study population lives in French Guiana in 3 different areas (Saül, Trois Sauts, and Cayenne and its surroundings), and eligible individuals (Populations 1 and 3) or those residing in a high-seroprevalence geographic area (Population 2) were identified by the National Reference Center (CNR) for Arboviruses at the Institut Pasteur of French Guiana (IPG) as part of arbovirus virological surveillance in French Guiana.
Key inclusion criteria (9 listed)
- Adults (≥18 years old)
- Willingness to participate in the study after explanation and signing of the informed consent form
- Presenting a laboratory-confirmed OROV infection, defined by a positive real-time RT-PCR and/or positive seroneutralization performed as part of the management of and response to the 2020 OROV epidemic in Saül.
- Residing in Trois-Sauts for at least 5 years
- Presenting a laboratory-confirmed OROV infection, defined by a positive real-time RT-PCR and/or positive seroneutralization, identified in the Cayenne area and surrounding localities during the study period, as part of the surveillance activities of the CNR for Arboviruses (IPG).
Key exclusion criteria (3 listed)
- Pregnant women.
- Individuals presenting with severe chronic pathologies (notably active cancer, primary or secondary immunodeficiency, immunosuppressive treatment, HIV infection, or autoimmune diseases), according to the information declared by the participants.
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 |
|---|---|---|
| 20 ml blood sampleA 20-ml blood sample | Other | adults recruited from Trois-Sauts with ∼80% seroprevalence, adults with confirmed past OROV infection (2020) recruited from Saül, newly confirmed OROV cases identified during the study period in the Cayenne region |
Primary outcome
Characterization of the adaptive immune response to OROV infection during the convalescent phase.
Time frame: 12 months
OROV-specific polyclonal antibodies will be detected in participants' plasma to confirm prior infection.
3 secondary outcomes
Isolate OROV-specific B cells (recognizing the Gn_Gc antigenic complex) and generate human monoclonal antibodies by single B cell culture.
Time frame: 12 months
Screening of secreted mAbs using OROV antigens and VDJ sequencing to characterize immunoglobulin repertoires.
Time frame: 12 months
Structural characterization of neutralizing mAbs by cryo-EM and nano-imaging to identify conserved epitopes.
Time frame: 12 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Nov 2026.
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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.
The record lists no contact. Use the official record to reach the sponsor.
Questions about this trial
What is this clinical trial studying?
An observational study of Oropouche Infection, run by Institut Pasteur.
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 9 inclusion and 3 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: opening soon, as of the sponsor's last update on 6 Nov 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
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?
Characterization of the adaptive immune response to OROV infection during the convalescent phase. (time frame: 12 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 6 Nov 2026.