Prospective Collaborative Study for Pulse Dexamethasone and Lenalidomide in Relapsed/Refractory Langerhans Cell
Ramya Uppuluri1, Manas Kalra2, Satyendra Katewa3
1Apollo Hospitals, Chennai, India.
Background:
The Indian Paediatric Haematology Oncology Group (INPHOG) multicentre study aimed to prospectively analyse the efficacy and safety of lenalidomide and dexamethasone (LENDEX) in children with refractory/relapsed Langerhans cell histiocytosis (LCH).
Procedure:
The study was a prospective, multicentre study conducted through the INPHOG Histiocytosis Subcommittee. The Clinical Trials Registry of India registration was obtained, and the study was open to recruitment from June 2020 to June 2023.
Results:
A total of 15 children were included from seven centres in India, median age being 4 years (Range 3-13 years). Thirteen children were diagnosed to have multisystem disease at relapse with involvement of skin, bone and liver; and one child each with multifocal bone disease and single site bone lesion. One child with refractory lung disease had progression after two cycles of LENDEX and was taken off protocol. Four (26%) children achieved CR after six cycles of LENDEX; while eight (53%) children had PR at three and six cycles, with CR at the end of nine cycles of LENDEX. The combination was well tolerated, the most common adverse effects being mild anaemia and myalgia. There were no deaths within the cohort, with a median follow-up of 24 months (Range 18-48 months). The overall response rate was 73%, with 26% responses at six cycles and 53% at nine cycles of LENDEX.
Conclusion:
LENDEX is well tolerated and effective in 73% children with relapsed/refractory LCH. Future studies would include nine cycles of LENDEX followed by maintenance for 12 months with 6-mercaptopurine.