Mpox (Monkeypox)POXAIMNCT07592429
Assessment of Immune Memory - Humoral and Cellular - in mPOX-infected Patients : an Ancillary Study of the ANRS0258s MOSAIC Cohort
A study testing blood sampling in people with Mpox (Monkeypox), run by ANRS, Emerging Infectious Diseases.
Trial summary
Primary objective The overall objective is to assess the long-term amplitude and durability of the immune responses after mpox virus (MPXV) infection. Primary endpoint The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Mpox (Monkeypox)
- What is being tested?
- blood sampling
- Type of treatment
- Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 60 participants
- Where
- No sites listed yet
- Study dates
- 1 Jul 2026to 1 Jul 2028
- Phase
- Interventional
- 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
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Written informed consent, signed by the participant and the investigator prior to any study-related procedure
- Person previously enrolled in the ANR0258s-MOSAIC cohort (see Appendix 19.2 for MOSAIC inclusion criteria) between July 2022 and July 2023
- Person with a blood sample taken within 8 months following mpox infection
- ≥ 18 years old
Who cannot join
- Individuals who, in the investigator's opinion, are unlikely to comply with study procedures or whose medical condition is incompatible with study participation
- For France only: person not affiliated to or not benefiting from a social security scheme in accordance with article L1121-11 of the French Public Health Code (Aide Médicale d'Etat [AME] does not constitute a social security scheme)
- Pregnant or breastfeeding women
- Individuals under guardianship or curatorship, or deprived of liberty by judicial or administrative decision
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Primary objective The overall objective is to assess the long-term amplitude and durability of the immune responses after mpox virus (MPXV) infection.
Primary endpoint The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells. Neutralizing antibodies titers will be measured with a semi-automated cell-based assay using live mpox virus. Memory B cells will be measured by flow cytometry and other techniques.
Read more
Secondary objectives
- Assess the amplitude and the stability of the MPXV antigen-specific B-cell memory response after infection, against the immunodominant antigens A27, A33, B5, L1, D8, and H3.
- Assess the breadth of the B-cell repertoire and its neutralizing capacity in a subset of patients
- Assess the humoral immunity using different serological techniques, for the detection and quantification of anti-MPXV antibodies, and assess the seroneutralization capacities of each antibody.
Secondary endpoints
- The presence of MPXV antigen-specific B-cell memory. Memory B cells will be measured by flow cytometry and other techniques.
- The breadth and neutralizing capacity of the B-cell repertoire in a subset of patients.
- The humoral immunity using serological techniques.
Read the detailed description
Single inclusion visit with data collection and blood sample. No further follow-up of participants.
A total of 60 participants previously enrolled in the main cohort ANRS 0758s MOSAIC are planned to be included, distributed among France (n = 35), Italy (n = 20), and Switzerland (n = 5).
- Conditions
- Mpox (Monkeypox)
- Being tested
- blood sampling
- Keywords
- mpox virus, Immune protection, Immune response, Immunity duration, Infection
- Medical subject headings
- Mpox, Monkeypox, Infections
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
blood samplingProcedure or surgery
Procedure: Patients included in the ANRS0758s MOSAIC cohort will be recalled >3 years after their infection to come to hospital to have a review of medical history since mpox infection, a clinical examination in case of symptoms suggestive of a mpox infection and samples taken for the study.
| Study group | Role | What they receive |
|---|---|---|
| study population | Experimental | Procedure: Patients included in the ANRS0758s MOSAIC cohort will be recalled >3 years after their infection to come to hospital to have a review of medical history since mpox infection, a clinical examination in case of symptoms suggestive of a mpox infection and samples taken for the study. Receives: Procedure: blood sampling |
What is being measured
The primary outcome is the main question the study is designed to answer.
The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells.
Neutralizing antibodies titers will be measured with a semi-automated cell-based assay using live mpox virus. Memory B cells will be measured by flow cytometry and other techniques.
Measured: Baseline (Day 1)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted18 May 2026
- Study start1 Jul 2026 (estimated)
- Primary completion1 Jul 2027 (estimated)
- Study completion1 Jul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Mpox (Monkeypox)Studies of the same condition, open and under way.
- More trials run by ANRS, Emerging Infectious DiseasesThe 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 N/A
- Primary purpose
- Health services research
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- ANRS, Emerging Infectious Diseases
- Sponsor type
- Other government
- Collaborators
- Assistance Publique - Hôpitaux de Paris
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07592429
- Sponsor's protocol ID
- ANRS0791s POXAIM
- Acronym
- POXAIM
- Status last verified
- May 2026
- First submitted
- 10 May 2026
- Last updated
- 18 May 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 18 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Assessment of Immune Memory - Humoral and Cellular - in mPOX-infected Patients : an Ancillary Study of the ANRS0258s MOSAIC Cohort
- ClinicalTrials.gov ID
- NCT07592429
- Acronym / sponsor ID
- POXAIM / ANRS0791s POXAIM
- Conditions
- Mpox (Monkeypox)
- Keywords
- mpox virus, Immune protection, Immune response, Immunity duration, Infection
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 60 participants (estimated)
- Lead sponsor
- ANRS, Emerging Infectious DiseasesOther government
- Collaborators
- Assistance Publique - Hôpitaux de Paris
- Study start
- 1 Jul 2026 (estimated)
- Primary completion
- 1 Jul 2027 (estimated)
- Study completion
- 1 Jul 2028 (estimated)
- First posted
- 18 May 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.
Primary objective The overall objective is to assess the long-term amplitude and durability of the immune responses after mpox virus (MPXV) infection.
Primary endpoint The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells. Neutralizing antibodies titers will be measured with a semi-automated cell-based assay using live mpox virus. Memory B cells will be measured by flow cytometry and other techniques.
Secondary objectives
- Assess the amplitude and the stability of the MPXV antigen-specific B-cell memory response after infection, against the immunodominant antigens A27, A33, B5, L1, D8, and H3.
- Assess the breadth of the B-cell repertoire and its neutralizing capacity in a subset of patients
- Assess the humoral immunity using different serological techniques, for the detection and quantification of anti-MPXV antibodies, and assess the seroneutralization capacities of each antibody.
Secondary endpoints
- The presence of MPXV antigen-specific B-cell memory. Memory B cells will be measured by flow cytometry and other techniques.
- The breadth and neutralizing capacity of the B-cell repertoire in a subset of patients.
- The humoral immunity using serological techniques.
Detailed description
Single inclusion visit with data collection and blood sample. No further follow-up of participants.
A total of 60 participants previously enrolled in the main cohort ANRS 0758s MOSAIC are planned to be included, distributed among France (n = 35), Italy (n = 20), and Switzerland (n = 5).
Study design
- Primary purpose
- Health services research
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| study population | Experimental | Procedure: blood samplingProcedure: Patients included in the ANRS0758s MOSAIC cohort will be recalled >3 years after their infection to come to hospital to have a review of medical history since mpox infection, a clinical examination in case of symptoms suggestive of a mpox infection and samples taken for the study. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Written informed consent, signed by the participant and the investigator prior to any study-related procedure
- Person previously enrolled in the ANR0258s-MOSAIC cohort (see Appendix 19.2 for MOSAIC inclusion criteria) between July 2022 and July 2023
- Person with a blood sample taken within 8 months following mpox infection
- ≥ 18 years old
Key exclusion criteria (4 listed)
- Individuals who, in the investigator's opinion, are unlikely to comply with study procedures or whose medical condition is incompatible with study participation
- For France only: person not affiliated to or not benefiting from a social security scheme in accordance with article L1121-11 of the French Public Health Code (Aide Médicale d'Etat [AME] does not constitute a social security scheme)
- Pregnant or breastfeeding women
- Individuals under guardianship or curatorship, or deprived of liberty by judicial or administrative decision
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 |
|---|---|---|
| blood samplingProcedure: Patients included in the ANRS0758s MOSAIC cohort will be recalled >3 years after their infection to come to hospital to have a review of medical history since mpox infection, a clinical examination in case of symptoms suggestive of a mpox infection and samples taken for the study. | Procedure or surgery | study population |
Primary outcome
The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells.
Time frame: Baseline (Day 1)
Neutralizing antibodies titers will be measured with a semi-automated cell-based assay using live mpox virus. Memory B cells will be measured by flow cytometry and other techniques.
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 18 May 2026.
- Individual participant dataSharing planned: No
Related trials for Mpox (Monkeypox)
RecruitingObservational study
Evaluation of Effectiveness and Safety of LC16m8 Mpox Vaccine in the Democratic Republic of Congo (DRC)
Mpox (Monkeypox), Mpox
Enrolling by invitationObservational study
New York City Observational Study of Mpox Immunity
Monkeypox, Mpox
Enrolling by invitation
Smart Analysis and Decision-Making for Emerging Infectious Diseases
Emerging Infectious Diseases, COVID-19
Active, not recruitingPhase 4
Smallpox Vaccine for Mpox Post-Exposure Prophylaxis: A Cluster RCT
Monkeypox
RecruitingPhase 2
A Randomized Clinical Trial Investigating the Safety, Reactogenicity, and Immunogenicity After Immunization With an mRNA-based Mpox Vaccine Candidate in Africa
Mpox (Monkeypox), Smallpox
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.
Questions about this trial
What is this clinical trial studying?
A study testing blood sampling in people with Mpox (Monkeypox), run by ANRS, Emerging Infectious Diseases.
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 4 inclusion and 4 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 18 May 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?
Contact Aida TAIEB (+33 (0)1 82 53 35 66, aida.taieb@inserm.fr), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells. (time frame: Baseline (Day 1)). 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 18 May 2026.