OBJECTIVES: Approaches to extrapolating treatment effects and valuing short- versus long-term benefits can differbetween chronic progressive conditions requiring treatment early in the disease course, such as Alzheimer’s disease(AlzDis), and chronic conditions treated in more severe stages, such as atopic dermatitis (ADerm). This study contrastseconomic evaluations in AlzDis and ADerm to illustrate how disease characteristics and extrapolation assumptionsimpact value assessments for two types of chronic conditions.
METHODS: We compared the Institute for Clinical and Economic Review’s (ICER’s) 2021 cost-effectiveness analyses forbiologic therapies in moderate-to-severe ADerm and for aducanumab in early AlzDis. Emphasis was placed oncomparing baseline populations, long-term progression, treatment effect extrapolation assumptions, treatmentdiscontinuation assumptions, timing of quality-adjusted life-year (QALY) gains, and pricing benchmarks.
RESULTS: The ADerm population started treatment in a more severe state than the AlzDis population (baselineutility=0.60 vs. 0.68-0.73). While ADerm only improved over time (no progression), AlzDis progressed to more advancedstates (lowest utility=0.31). The ADerm treatment effect (response) produced immediate QALY gains and persistedwithout waning for responders remaining on treatment. The AlzDis treatment effect (reduction in progression) wasapplied fully only in the baseline state, waned with progression, and stopped prior to treatment discontinuation. QALYgains in AlzDis accrued indirectly by slowing progression and extending survival and thus were delayed anddiscounted. Trial-based treatment discontinuation was extrapolated for ADerm but was not extrapolated for AlzDis.Age differences (ADerm=36.5 years; AlzDis=70 years) contributed primarily through higher competing mortality risksfor AlzDis. ICER’s resulting benchmark prices at $100,000/QALY gained for ADerm biologic therapies($24,400-$30,600/year) were higher than the benchmark price range for aducanumab for AlzDis ($1,650-$11,000/year).
CONCLUSIONS: Conventional value assessment approaches may inequitably value treatments for chronic progressiveconditions requiring early, preventive treatment. Such conditions merit inclusion in ongoing discussions on augmentedand/or risk-adjusted cost-effectiveness analysis.
