Skip to content

Assessment of Immune Memory - Humoral and Cellular - in mPOX-infected Patients : an Ancillary Study of the ANRS0258s MOSAIC Cohort

Assessment of Immune Memory - Humoral and Cellular - in mPOX-infected Patients : an Ancillary Study of the ANRS0258s MOSAIC Cohort

Status
Not yet recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07592429
Acronym
POXAIM
Enrollment
60
Registered
2026-05-18
Start date
2026-07-01
Completion date
2028-07-01
Last updated
2026-05-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Mpox (Monkeypox)

Keywords

mpox virus, Immune protection, Immune response, Immunity duration, Infection

Brief 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. 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 1. 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. 2. Assess the breadth of the B-cell repertoire and its neutralizing capacity in a subset of patients 3. 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 1. The presence of MPXV antigen-specific B-cell memory. Memory B cells will be measured by flow cytometry and other techniques. 2. The breadth and neutralizing capacity of the B-cell repertoire in a subset of patients. 3. 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).

Interventions

PROCEDUREblood sampling

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.

Sponsors

ANRS, Emerging Infectious Diseases
Lead SponsorOTHER_GOV
Assistance Publique - Hôpitaux de Paris
CollaboratorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
HEALTH_SERVICES_RESEARCH
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* 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

Exclusion criteria

* 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

Design outcomes

Primary

MeasureTime frameDescription
The main outcomes are: the presence of neutralizing antibodies in the serum and the presence of detectable mpox virus-specific memory B cells.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.

Contacts

CONTACTAida TAIEB
aida.taieb@inserm.fr+33 (0)1 82 53 35 66

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: May 19, 2026