Assessing the cost-effectiveness of COX-2 specific inhibitors for arthritis in the Veterans Health Administration.

OBJECTIVE

This study was designed to assess the cost-effectiveness of cyclooxygenase-2 specific (COX-2) inhibitors (rofecoxib and celecoxib) over nonselective nonsteroidal anti-inflammatory drugs (NSAIDs) in high-risk arthritis patients from the perspective of the Veterans Health Administration (VA).

METHODS

This literature-based economic analysis (with data summarized from MEDLINE-indexed and other published sources, FDA reports, and data on file at VA San Diego Healthcare System) compared rofecoxib and celecoxib to NSAIDS in two arthritis patient populations considered at higher risk of developing clinically significant upper gastrointestinal events (CSUGIEs): (1) patients of any age with previous medical history of perforation/ulcer/bleed (PUB); and (2) patients 65 years and older (regardless of history of PUB). Two outcome measures were reported: (1) incremental cost per CSUGIE averted over 1 year; and (2) incremental cost per quality-adjusted life-year (QALY) gained, considering both the mortality and morbidity associated with gastrointestinal (including CSUGIEs) and cardiovascular-related adverse events. When possible, costs were modeled to reflect the VA perspective. Sensitivity analyses were conducted to test the robustness of the analysis.

RESULTS

Compared to NSAIDS, rofecoxib and celecoxib increased costs but reduced the incidence of CSUGIE. Cost per CSUGIE avoided were $7476 and $16,379 (in patients with a PUB history) and $14,294 and $18,376 (in patients aged > or = 65 years) for celecoxib and rofecoxib, respectively. In both populations, celecoxib was associated with a cost per QALY less than $50,000. In contrast, rofecoxib was found to cost more and result in a net QALY loss, due in particular to the increase in the risk of cardiovascular complications, and was therefore considered cost-ineffective. Results were most dependent on assumptions about the incidence of cardiovascular events and CSUGIE and the COX-2 inhibitors' acquisition price.

CONCLUSIONS

This analysis suggests that COX-2 inhibitors may be cost-effective from the perspective of the VA. However, cost-effectiveness appears to depend less on the specific characteristics of the high-risk target population considered but more on the agent evaluated. Celecoxib appears to be an alternative to traditional NSAIDs in the patient populations studied.