Childhood cerebral adrenoleukodystrophy (CCALD) in France: epidemiology, natural history, and burden of disease - A population-based study.

BACKGROUND: X-linked adrenoleukodystrophy (ALD) is a rare metabolic and neurodegenerative disorder belonging to the group of leukodystrophies, with an estimated incidence around 1:25 000 newborns worldwide, mostly among men. Childhood Cerebral ALD (CCALD) is the most severe form with a poor prognosis if not properly treated during the first years of life. Currently, only allogeneic hematopoietic stem cell transplantation (allo-HSCT) is widely available for CCALD treatment. To date, there is a lack of data regarding CCALD epidemiology, natural history, and current management in France. This knowledge is crucial for the development of new therapies such as gene therapies. In this context, the French National Health Data System (SNDS) is a particularly indicated database to collect information meeting these needs. A non-interventional, national, real-life, retrospective study was performed using secondary data from the national ALD registry (LEUKOFRANCE) and SNDS. CCALD patients detected between 2009 and 2018 and successfully matched between LEUKOFRANCE and SNDS were included in this study. Index date was defined as the first CCALD event detected during study period. Subgroups of patients with sufficient follow-up (6 months) and history (1 year) available around index date were analyzed to assess CCALD burden and natural history. RESULTS: 52 patients were included into the matched cohort. Median annual incidence of CCALD was estimated at 4 patients. Median age at CCALD diagnosis was 7.0 years. Among patients without allo-HSCT, five-year overall survival was 66.6%, with 93.3% of them presenting at least one CCALD symptom and 62.1% presenting a least one major functional disability (MFD). Among patients with allo-HSCT, five-year overall survival was 94.4%, with only 11.1% of patients presenting CCALD symptoms, and 16.7% of presenting a MFD. Mean annualized costs were almost twice as important among patients without allo-HSCT, with 49,211€, 23,117€, respectively. Costs were almost exclusively represented by hospitalizations. CONCLUSIONS: To the best of our knowledge, this is the most up to date study analyzing CCALD epidemiology, clinical and economic burden in France. The necessity of a precocious management with HSCT highlight the potential benefits of including an expanded screening program among newborns, coupled with family screenings when a mutation is detected.

Cost-effectiveness analysis of elbasvir-grazoprevir regimen for treating hepatitis C virus genotype 1 infection in stage 4-5 chronic kidney disease patients in France.

OBJECTIVE: To assess the cost-effectiveness of the elbasvir/grazoprevir (EBR/GZR) regimen in patients with genotype 1 chronic hepatitis C virus (HCV) infection with severe and end-stage renal disease compared to no treatment. DESIGN: This study uses a health economic model to estimate the cost-effectiveness of treating previously untreated and treatment experienced chronic hepatitis C patients who have severe and end stage renal disease with the elbasvir-grazoprevir regimen versus no treatment in the French context. The lifetime homogeneous markovian model comprises of forty combined health states including hepatitis C virus and chronic kidney disease. The model parameters were from a multicentre randomized controlled trial, ANRS CO22 HEPATHER French cohort and literature. 1000 Monte Carlo simulations of patient health states for each treatment strategy are used for probabilistic sensitivity analysis and 95% confidence intervals calculations. The results were expressed in cost per quality-adjusted life year (QALY) gained. PATIENTS: The mean age of patients in the HEPATHER French cohort was 59.6 years and 56% of them were men. 22.3% of patients had a F0 fibrosis stage (no fibrosis), 24.1% a F1 stage (portal fibrosis without septa), 7.1% a F2 stage (portal fibrosis with few septa), 21.4% a F3 stage (numerous septa without fibrosis) and 25% a F4 fibrosis stage (compensated cirrhosis). Among these HCV genotype 1 patients, 30% had severe renal impairment stage 4, 33% had a severe renal insufficiency stage 5 and 37% had terminal severe renal impairment stage 5 treated by dialysis. INTERVENTION: Fixed-dose combination of direct-acting antiviral agents elbasvir and grazoprevir compared to no-treatment. RESULTS: EBR/GZR increased the number of life years (6.3 years) compared to no treatment (5.1 years) on a lifetime horizon. The total number of QALYs was higher for the new treatment because of better utility on health conditions (6.2 versus 3.7 QALYs). The incremental cost-utility ratio (ICUR) was of €15,212 per QALY gained for the base case analysis. CONCLUSIONS: This cost-utility model is an innovative approach that simultaneously looks at the disease evolution of chronic hepatitis C and chronic kidney disease. EBR/GZR without interferon and ribavirin, produced the greatest benefit in terms of life expectancy and quality-adjusted life years (QALY) in treatment-naïve or experienced patients with chronic hepatitis C genotype 1 and stage 4-5 chronic kidney disease including dialysis patients. Based on shape of the acceptability curve, EBR/GZR can be considered cost-effective at a willingness to pay of €20,000 /QALY for patients with renal insufficiency with severe and end-stage renal disease compared to no treatment.