ECLA is a phase II, multicenter study testing sub cutaneous cladribine 0.1mg/kg/j during 5 days, administrated every month for 4 courses, in symptomatic adult patients with pulmonary Langerhans cell histiocytosis and impairment of lung function patients.

ECLA is a phase II, multicenter study testing sub cutaneous cladribine 0.1mg/kg/j during 5 days, administrated every month for 4 courses, in symptomatic adult patients with pulmonary Langerhans cell histiocytosis and impairment of lung function patients.

Inclusion Criteria:

• Age 16 to 55 yr

• Histologically proven pulmonary Langerhans cell histiocytosis ( patients with presumptive diagnosis whose lung function precludes lung biopsy may be included after revision of their medical record at the national reference center for Langerhans cell histiocytosis)

• Symptomatic pulmonary Langerhans cell histiocytosis (NYHA dyspnea class ≥2) with:

  • irreversible airflow obstruction (FEV1/FVC<70%) with postbronchodilator FEV1 comprised between 30 and 70% of predicted
  • and/or decrease ≥15% in FEV1, FVC or DLCO as compared to baselines values in the year preceding the inclusion

• Signed written informed consent

Exclusion Criteria:

• Women at childbearing age without adequate contraception or wishing breastfeeding
• Male without adequate contraception during the study
• Dyspnea due to severe pulmonary arterial hypertension (PAP≥35mmHg) confirmed by cardiac right catheterism
• Previous malignancy
• Current infectious disease
• Renal failure
• Liver failure
• Severe alteration of lung
• Hematologic disease unrelated to Langerhans cell histiocytosis
• Epilepsy
• Hepatic, spleen or hematology involvement by Langerhans cell histiocytosis
• Pneumothorax within a month previously to inclusion
• Previous treatment with cladribine
• Contra indication to the use of cladribine
• Previous myelosuppressive treatment
• Simultaneous participation to another interventional clinical trial