ClinicalTrials.Veeva

Menu

Ex Vivo Study of Leukocyte Responses in the Blood of Patients With Leptospirosis and ex Vivo Testing of a New Host-targeted Therapeutic Strategy to Restore Phagocytosis of Leptospira (NEUTROLEPTO-NC)

Pasteur Institute logo

Pasteur Institute

Status

Not yet enrolling

Conditions

Jarisch Herxheimer Reaction
Leptospirosis

Treatments

Other: 16 ml blood sample at H3
Other: 24 ml blood sample at H0

Study type

Observational

Funder types

Industry
Other

Identifiers

NCT07611591
2025-146
2025-A02688-41 (Other Identifier)

Details and patient eligibility

About

Leptospirosis is a neglected zoonosis caused by pathogenic spirochetes of the genus *Leptospira*, occurring mainly in humid tropical and subtropical regions. With over one million cases and ~60,000 deaths annually, it is among the most dangerous bacterial zoonoses worldwide. Its nonspecific onset-fever, headache, myalgia-mimics influenza, dengue, and other acute febrile illnesses, making diagnosis difficult. Delayed antibiotic treatment can lead to severe forms (in ~10% of cases) characterized by hemorrhage and multi-organ failure. In 2023, New Caledonia reported 152 cases, with 85% hospitalized and a 2.6% mortality rate.

This study aims to characterize the human host response and improve patient management. *Leptospira* evades innate immunity, triggering a strong anti-inflammatory IL-10 response and potentially ineffective phagocytosis. However, the WHO-recommended β-lactam antibiotics induce a Jarisch-Herxheimer reaction (JHR)-an acute inflammatory response occurring within hours of treatment-in over 50% of patients (LEPJAR study, PMID:40986630), the impact of which on phagocytosis is unknown.The NEUTROLEPTO study will be conducted in New Caledonia (NC) in patients with or without leptospirosis. Clinical and biological data will be collected at the time of suspected infection and 3 hours after antibiotic administration. Specifically, immune responses will be assessed through cytokine profiling and blood cell phenotyping, as well as by transcriptome analysis of infected patients before and after antibiotic treatment.

Full description

The aim of the study is to compare the immune cell responses in the blood of patients hospitalized for leptospirosis with those of patients with another infection, before and 3 hours after antibiotic therapy.

Individuals presenting to the emergency department of the Territorial Hospital Center of New Caledonia with signs and symptoms of leptospirosis will be recruited:

-with a confirmed diagnosis of leptospirosis (Group 1),-

-with an infectious diagnosis other than leptospirosis (Group 2)

Blood and clinical data will be collected from all the participants.

Enrollment

70 estimated patients

Sex

All

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

  • Be of legal age (18 years or older at the time of enrollment),
  • Be capable of understanding and providing informed consent,
  • Have received information and provided written consent,
  • Be enrolled in a social security program.
  • Be suspected of having leptospirosis

Exclusion criteria

  • With a chronic inflammatory disease,
  • Whose health condition is incompatible with additional blood draws totaling 40 ml,
  • Receiving concomitant treatment with antibiotics and/or anti-inflammatory drugs, or undergoing medical treatment incompatible with the study's objectives,
  • Pregnant or breastfeeding women.
  • Hospitalized or having undergone surgery within the previous 7 days

Trial design

70 participants in 2 patient groups

Individuals with symptoms of leptospirosis with a confirmed diagnosis of leptospirosis
Treatment:
Other: 24 ml blood sample at H0
Other: 16 ml blood sample at H3
Individuals with symptoms of leptospirosis with a diagnosis of an infection other than leptospirosis
Treatment:
Other: 24 ml blood sample at H0
Other: 16 ml blood sample at H3

Trial contacts and locations

0

Loading...

Data sourced from clinicaltrials.gov

Clinical trials

Find clinical trialsTrials by location
© Copyright 2026 Veeva Systems