Abstract
Purpose: :
To develop a comprehensive, health–economic assessment to compare Macugen (pegaptanib sodium), a new treatment indicated for all patients with neovascular, age–related macular degeneration (AMD), to a historical control of untreated AMD patients.
Methods: :
A Markov framework was used to model the lifetime movement of an AMD cohort through five health states based on visual acuity (VA): >20/40, 20/40 to >20/80, 20/80 to >20/200, 20/200 to >20/400, and ≤20/400. The model incorporates patients across all lesion subtypes: predominately classic, minimally classic, and occult. All drug and procedure costs were derived from US published sources, including Medicare Part B Drugs Average Sales Prices and the RBRVS. Expert interviews were conducted to determine adverse event (AE) treatment patterns and vision rehabilitation resource use. Costs associated with declining VA (including costs associated with depression, injuries, and skilled nursing facility care) were extracted from a Medicare analysis. Transition probabilities for Macugen were derived from published efficacy results of the VISION study. Transition probabilities for untreated patients are based on the natural progression of the disease, which the model assumes is represented by efficacy results among untreated patients in the placebo arm of photodynamic therapy with verteporfin clinical trials. Utilities were obtained from similar published sources as used in previous AMD models. Outcomes of the model include vision years, quality–adjusted life years (QALYs), drug costs, AMD–related medical costs, AE costs, and costs associated with declining VA, as well as the incremental cost per vision year and QALY gained.
Results: :
In matched cohorts, patients treated with Macugen had 3.87 vision years and 4.16 QALYs after diagnosis compared to 2.35 vision years and 3.58 QALYs for untreated patients over the remainder of their lifetime. The incremental cost per vision year gained and the incremental cost per QALY gained were $5,701 and $14,918, respectively, for Macugen vs. no treatment.
Conclusions: :
Macugen yields better patient outcomes (vision years and QALYs) than no treatment and is cost–effective compared to no treatment. A limitation of the model is the absence of a direct clinical comparison between the two comparator arms.
Keywords: aging • age-related macular degeneration • clinical (human) or epidemiologic studies: health care delivery/economics/manpower