Cost-Effectiveness Comparison: FOLFIRI versus FOLFOX

Wayne Kuznar

February 2011, Vol 2, No 1 - Meeting Highlights

Anaheim, CA—As first-line treatment of metastatic colorectal cancer, a regimen of leucovorin, 5-fluorouracil, and irinotecan (FOLFIRI) is more costeffective than a regimen of leucovorin, 5-fluorouracil, and oxaliplatin (FOLFOX), investigators at Northeastern Uni versity School of Pharmacy, Boston, have suggested. They presented their data at the clinical meeting of the American Society of Health-System Pharmacists.

The slight survival advantage of – fered by the FOLFOX regimen is outweighed by a more than $500,000 increase in total costs, the researchers believe. However, in a 1-way sensitivity analysis, when the cost of the FOLFOX regimen exceeds $2621.60, FOLFIRI is the more cost-effective treatment regimen.

Both FOLFOX and FOLFIRI are first-line chemotherapy regimens for meta static colorectal cancer; “however, each regimen causes a broad array of adverse reactions that influences costs to third-party payers,” according to the investigators.

They performed a modeled costeffectiveness analysis of the 2 chemotherapy regimens, administered every 2 weeks for 10 cycles.

Average wholesale prices were used to calculate the cost of the treatment regimens and the cost associated with side effects.

The costs of clinic visits and hospitalizations were derived from the Centers for Medicare & Medicaid Services fee schedules.

Randomized controlled trials and US Food and Drug Administration monographs were used to determine survival at 18 months and the probabilities of adverse drug reactions.

Patients were assumed to have stage IV metastatic colorectal cancer. The cost analysis did not take into account dose reductions resulting from adverse drug reactions, the use of adjunct chemotherapy, or the costs of second-line chemotherapy regimens. The costs per 10-day cycle were $49,031 for FOLFOX compared with $36,922 for FOLFIRI.

The probability of survival at 18 months was 52% with the FOLFOX regimen and 50% with the FOLFIRI regimen, yielding average cost-effectiveness ratios of $93,606 per patient surviving at 18 months with FOLFOX versus $71,502 with FOLFIRI.

The incremental cost-effectiveness ratio was an additional $646,200 per pa tient surviving with FOLFOX treatment at 18 months versus FOLFIRI treatment.