Cost-effectiveness of a fixed combination of hydroquinone/tretinoin/fluocinolone cream compared with hydroquinone alone in the treatment of melasma

Journal of Drugs in Dermatology, Feb, 2007 by Tania Cestari, Lucie Adjadj, Margaret Hux, Maria Regina Shimizu, Vincent Pierre Rives

A pharmacoeconomic evaluation compares the incremental effectiveness of treatments with the total disease-related cost comparing 2 treatment strategies (ie, the acquisition cost of medications and also health resources required) due to differences in treatment safety and effectiveness. When treatments have differences in their associated clinical outcomes, the type of pharmacoeconomic evaluation will depend on the method used to express the difference in clinical outcome. (21) Cost-utility analyses compare the cost per quality-adjusted life-year for 2 or more interventions. Cost-benefit analyses measure the difference in outcome in monetary terms; and cost-effectiveness analyses measure the variation in clinical outcome using clinical units familiar to physicians.

Depending on the decision-making perspective from which the analysis is being undertaken (eg, third-party payer, health authorities, insurance company, patients, society), different components of health care costs are included in the total cost estimate. A health care payer perspective would include only direct costs, which are medical care resources such as drugs, medical visits, hospitalization, and additional costs for diagnosis, treatment required for the disease, complications, or adverse effects. A societal perspective would also include indirect costs such as those resulting from changes in productive capacity brought about by the drug or other health intervention (loss of work days, personal expenses). It may also include intangible costs or those associated with additional pain and suffering attributable to a new medical intervention or drug. (22)

Full economic trials that include the evaluation of costs and clinical outcomes in a typical care setting for an appropriate time period to address the cost-effectiveness question are rare. Often, economic analyses may require the use of outcome and cost data collected from existing research. A randomized clinical trial within which clinical outcomes and costs are simultaneously collected can be an excellent basis for such a study.

When an economic evaluation is based on different sources of clinical information and assumptions are made to extrapolate the results to the studied population, the base case analysis will present the cost-effectiveness result using the inputs for each variable from the trial. Sensitivity analysis can provide a tool to evaluate the assumptions and the effects of such assumptions on study results by varying values of the variables. (21)

The objective of the current economic assessment is to evaluate and present the cost-effectiveness, over an 8-week time frame, of treating patients with moderate to severe facial melasma with either TCT once daily or a standard regimen of twice daily hydroquinone 4% in the US, Argentina, Brazil, Colombia, and Chile. Cost-effectiveness was chosen because the study compared 2 treatments that resulted in 2 different levels of success.

Methods

Clinical and health resource use data for cost-effectiveness analyses were obtained from a randomized, open-label, multicenter clinical trial of TCT cream once daily (hydroquinone 4%, tretinoin 0.05% and fluocinolone acetonide 0.01%) compared to hydroquinone 4% cream twice daily conducted in Brazil. (19) Women not currently pregnant or men presenting to a dermatologist for treatment of moderate to severe melasma were randomized between the 2 groups. A dermatologist assessed their melasma lesions using the severity rating scale at baseline and after 8 weeks. Subjects were followed every 2 weeks and prompted to report any adverse events.