Evaluation of IFNγ and Inflammatory Mediators in Patients With Hemophagocytic Lymphohistiocytosis

An Observational, Multicenter Study to Evaluate Levels of Interferon Gamma (IFNγ) and Other Inflammatory Mediators in Adult Patients With Hemophagocytic Lymphohistiocytosis (A-HLH)

This observational study is designed to provide a better understanding of the potential use of interferon gamma (IFNγ) and IFNγ-inducible chemokines as markers of HLH disease activity in adults, and the potential of IFNγ to represent a therapeutic target.

This is a observational study designed to determine the levels of pro-inflammatory markers in adult patients diagnosed with HLH and to assess the relationship between the biomarkers and disease activity in these patients during the HLH course. Inflammatory markers include IFNγ and IFNγ-induced chemokines C-X-C chemokine ligand 9 and C-X-C chemokine ligand 10.

In addition to the blood samples for the biomarker analysis, relevant information gathered by the treating physician will be collected in a data collection form. Whenever possible, collection of serum samples for biomarker analysis and relevant information should occur at HLH diagnosis, at regular time intervals during the treatment course (not more than once a week) up to resolution of HLH.

Blood samples will also be sent to the study sponsor (NovImmune S.A.) for cytokine testing. Before patient's samples are sent to the sponsor for testing, patient's name and any personal identifying information will be coded to protect participant's privacy.

Inclusion Criteria:

• Patients >=18 years old diagnosed with active HLH as established by the treating physician.
• HLH forms of unknown origin or secondary to infections or rheumatologic disorders.
• Should the diagnosis of primary HLH or malignancy become apparent after inclusion, the data collected will be analyzed separately as additional cohorts.
• The patient must have consented to the use of their clinical data for research purposes at the site.

Exclusion Criteria:

• Patients with primary HLH (diagnosed by the presence of homozygous mutations in a known HLH causative gene) and secondary HLH due to malignancy are excluded.