Objective: We estimate the cost-effectiveness of alternative initial drug treatments of invasive pulmonary aspergillosis (IPA) in suspected earlier and later lung involvement, based on the presence or absence of the halo sign on thoracic computed tomography (CT). Methods: We constructed a decision analysis model comparing 12-week treatment outcomes for a subset of patients enrolled in a clinical trial of initial treatment of IPA with amphotericin B dexoycholate (AmBd) vs voriconazole (VOR). Patients included those with suspected lung involvement who underwent a baseline thoracic CT. The subset was subdivided into two groups based on the presence or absence of a characteristic CT halo sign, a perimeter of ground glass CT opacity surrounding a solid lung nodule ≥ 1 cm diameter, known as an early indicator of IPA. Healthcare resource use and survival data were obtained directly from the clinical trial. US unit costs for drugs and health care services were applied from standard data sources. Cost and survival at 12-weeks were estimated for those with and without a halo sign at baseline. Incremental cost-effectiveness ratios comparing VOR to AmBd were calculated for both patient subgroups. Sensitivity of results to uncertainty in health care use and cost estimates was tested. Results: Patients in the halo subgroup had better survival than those in the no-halo subgroup (70.6% vs 54.4%), with lower total treatment cost ($44,352 vs $47,077). Survival was higher for VOR than for AmBd in both patient subgroups (halo: 75.3% vs 65.2%; no-halo: 68.3% vs 39.5%). In the halo subgroup, total costs were lower for those treated with VOR than for those treated with AmBd ($40,380 vs $48,985). In the no-halo subgroup, total cost per patient was slightly higher for those treated with VOR ($48,133 vs $45,938). Accounting for the difference in survival, the incremental cost-effectiveness ratio for VOR compared to AmBd was $7,625 per additional 12-week survivor in this subgroup. Conclusions: Earlier identification and treatment of IPA appears to result in better survival and potentially lower costs than later treatment. Initial treatment of IPA with VOR improves survival in patients with early or late disease compared with AmBd, is cost saving in the halo sub-group, and is cost-effective in the no-halo subgroup, within the constraints of our analysis.
Full conference title:
16th European Congress of Clinical Microbiology and Infectious Diseases
- ECCMID 16th (2006)