Efficacy and Safety of Interferon-Gamma Monoclonal Antibody Combined With Dexamethasone in the Treatment of Refractory Adult Secondary Hemophagocytic Lymphohistiocytosis

The goal of this observational study is to learn if interferon-gamma monoclonal antibody combined with dexamethasone works to treat adults with refractory secondary hemophagocytic lymphohistiocytosis (HLH). The main questions it aims to answer are:

How well does this treatment help patients recover from refractory secondary HLH? How safe is this treatment for these patients? Participants will receive interferon-gamma monoclonal antibody and dexamethasone as part of their clinical care. Researchers will monitor participants with regular blood tests, physical exams, and safety checks for up to 8 weeks of treatment. They will collect information about how participants respond to treatment and any side effects that occur.

This study will include about 22 adult participants at Huadong Hospital Affiliated to Fudan University.

Study Overview

• Status: Completed
• Conditions: Secondary Hemophagocytic Lymphohistiocytosis; HLH; Adult Refractory Secondary Hemophagocytic Lymphohistiocytosis

• Study Type: Observational
• Enrollment (Actual): 22

Contacts and Locations

Study Locations

• China
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 200040
      • Huadong Hospital, Fudan University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

This study will enroll adult participants aged 18 years and older with a confirmed diagnosis of refractory secondary hemophagocytic lymphohistiocytosis (HLH) based on the HLH-2004 diagnostic criteria. Participants must have demonstrated inadequate response or disease progression following standard first-line or second-line HLH-directed therapy. All participants must be able to provide written informed consent prior to any study-related procedures.

Description

Inclusion Criteria:

• Age ≥ 18 years
• Confirmed diagnosis of secondary hemophagocytic lymphohistiocytosis (HLH) according to HLH-2004 criteria
• Refractory HLH defined as inadequate response or progression after at least 2 weeks of standard first-line or second-line therapy
• Able to provide written informed consent

Exclusion Criteria:

• Active infection with mycobacteria, histoplasma, CMV, herpes zoster, or HIV
• Left ventricular ejection fraction < 50%
• Concurrent use of other anti-neoplastic or investigational agents
• Other uncontrolled infections judged by the investigator
• Psychiatric disorders or poor protocol compliance

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Observation group; Participants receive IFN-γ monoclonal antibody by weight-based intravenous infusion. Dexamethasone is administered orally or intravenously. Prophylaxis for infections and standard supportive care are provided as clinically needed. Treatment continues for up to 8 weeks, with regular safety and efficacy assessments.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Response Rate (ORR)	The proportion of participants who achieve complete response (CR) or partial response (PR) at the end of 8-week treatment, defined by normalized or improved clinical and laboratory parameters including ferritin, triglycerides, sCD25, blood cell counts, and hemophagocytosis.	Up to 8 weeks after initiation of treatment

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Progression-Free Survival (PFS)	Time from treatment start to disease progression or death from any cause, whichever occurs first.	Up to 12 months after treatment initiation
Overall Survival (OS)	Time from treatment start to death from any cause.	Up to 12 months after treatment initiation
Incidence of Adverse Events (AEs) and Serious Adverse Events (SAEs)	Number and severity of treatment-emergent adverse events and serious adverse events, graded according to NCI-CTCAE v5.0.	Up to 28 days after the last dose of study treatment

Collaborators and Investigators

• Sponsor: Fudan University

Study record dates

Study Major Dates

• Study Start (Actual): May 21, 2024
• Primary Completion (Actual): August 31, 2025
• Study Completion (Actual): August 31, 2025

Study Registration Dates

• First Submitted: April 2, 2026
• First Submitted That Met QC Criteria: April 11, 2026
• First Posted (Actual): April 15, 2026

Study Record Updates

• Last Update Posted (Actual): April 15, 2026
• Last Update Submitted That Met QC Criteria: April 11, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: 2024K017

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Time Frame: 1 year after completion of this study
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No