Efficacy of denosumab monotherapy among adults with Langerhans cell histiocytosis: A prospective clinical trial.

This phase IIb clinical trial evaluated the efficacy of a bimonthly treatment schedule (Q8W) with 4 subcutaneous doses of denosumab 120 mg among adults with Langerhans cell histiocytosis needing first-line systemic therapy for either multifocal single-system disease or multisystem disease without risk organ involvement. Two months after the last treatment administration, seven patients showed disease regression, one stable disease, one non-active disease, and one disease progression. One year after treatment, progression was evident in two patients, while the remaining exhibited either a regression (three patients) or non-active disease (five patients). No permanent sequalae developed during the study and no adverse events were adjudicated in treatment. In conclusion, four doses of denosumab 120 mg Q8W subcutaneously are an effective treatment option in Langerhans cell histiocytosis patients without risk organ involvement exhibiting a response rate of 80%. Further studies are needed to confirm its role as a disease modifying agent.