FROM CURRENT TREATMENT GAPS TO POPULATION ESTIMATION: TWO STRATEGIES FOR QUANTIFYING THE POTENTIAL TARGET POPULATION IN PEDIATRIC RELAPSED/REFRACTORY LANGERHANS CELL HISTIOCYTOSIS IN CHINA
Author(s)
Lili Cheng, MBA1, Zigang Li, MSc2, Yang Yang, MSc2, Keruo Zhou, MSc2, Xin Chen, MSc2.
1Jiangsu Provincial Pharmacy Association (JPPA), Nanjing, China, 2Shanghai Fosun Pharmaceutical (Group) Co., Ltd., Shanghai, China.
1Jiangsu Provincial Pharmacy Association (JPPA), Nanjing, China, 2Shanghai Fosun Pharmaceutical (Group) Co., Ltd., Shanghai, China.
OBJECTIVES: Langerhans cell histiocytosis (LCH) is a rare inflammatory neoplastic disease with peak onset at 1-4 years. Vinblastine plus steroids is the current standard first-line therapy for pediatric LCH, but with a high recurrence rate and limited efficacy in high-risk patients, leading to relapsed or refractory (R/R) conditions. This study aims to characterize the treatment landscape for R/R LCH in China and estimate the two-year potential population of R/R LCH children and adolescent patients aged ≥2 years with at least one prior systemic therapy using two calculation strategies.
METHODS: A targeted literature review was conducted through PubMed, CNKI, and the 2025-version Chinese National Reimbursement Drug List. Extracted data included incidence and prevalence of LCH, treatment recommendations, and domestic treatment practices. Two methods were used to estimate the potential population size of R/R LCH patients in China, based respectively on the prevalence and age-stratified incidence rates. The prevalence-based method adopted the 7-year prevalence for estimation, while the incidence-based method divided patients into two groups according to disease onset age and performed 17-year cumulative calculations. Key parameters were also adjusted to test the uncertainty of the results.
RESULTS: There is presently no standard therapy for pediatric R/R LCH in China. Cytarabine plus cladribine is commonly used off-label, and empirical clinical evidence is lacked. Guidelines recommend MEK/BRAF inhibitors for treatment, but apart from luvometinib, no drug has been approved worldwide for R/R pediatric LCH. The prevalence-based method estimated 769 and 768 patients, while the incidence-baes method estimated 1,638 and 1,609 patients for the year 2027 and 2028. Using the minimum available R/R rate reduced estimates to 175/174 and 372/366 respectively.
CONCLUSIONS: R/R LCH remains the central challenge. Treatment options are extremely limited worldwide, and unmet medical needs are significant. Despite fluctuations due to epidemiological data limitations, these estimates provide a useful reference for future health technology assessments.
METHODS: A targeted literature review was conducted through PubMed, CNKI, and the 2025-version Chinese National Reimbursement Drug List. Extracted data included incidence and prevalence of LCH, treatment recommendations, and domestic treatment practices. Two methods were used to estimate the potential population size of R/R LCH patients in China, based respectively on the prevalence and age-stratified incidence rates. The prevalence-based method adopted the 7-year prevalence for estimation, while the incidence-based method divided patients into two groups according to disease onset age and performed 17-year cumulative calculations. Key parameters were also adjusted to test the uncertainty of the results.
RESULTS: There is presently no standard therapy for pediatric R/R LCH in China. Cytarabine plus cladribine is commonly used off-label, and empirical clinical evidence is lacked. Guidelines recommend MEK/BRAF inhibitors for treatment, but apart from luvometinib, no drug has been approved worldwide for R/R pediatric LCH. The prevalence-based method estimated 769 and 768 patients, while the incidence-baes method estimated 1,638 and 1,609 patients for the year 2027 and 2028. Using the minimum available R/R rate reduced estimates to 175/174 and 372/366 respectively.
CONCLUSIONS: R/R LCH remains the central challenge. Treatment options are extremely limited worldwide, and unmet medical needs are significant. Despite fluctuations due to epidemiological data limitations, these estimates provide a useful reference for future health technology assessments.
Conference/Value in Health Info
2026-09, ISPOR Asia Pacific 2026, Bangkok, Thailand
Value in Health, Volume 55, Issue S1
Code
EPH8
Topic
Epidemiology & Public Health
Topic Subcategory
Public Health
Disease
SDC: Pediatrics, SDC: Rare & Orphan Diseases