Willingness to Pay for Sensory Attributes of Intranasal Corticosteroids Among Patients With Allergic Rhinitis

OBJECTIVES: Sensory attributes of intranasal corticosteroids (INSs) differ by product based on chemical composition. We previously reported that patients are able to demonstrate preferences for certain INS sensory attributes, which may affect their willingness to adhere to therapy. As part of the same study, we also sought to determine if these same patients are willing to pay for products not containing certain sensory attributes. METHODS: We conducted a 2-part cross-sectional study of 120 patients with allergic rhinitis at 4 allergy and immunology clinics in the United States in November and December 2003. In the first part of the study, the patients chose between pairs of hypothetical INS products that differed in the intensity of 6 sensory attributes (smell, taste, aftertaste, throat rundown, nose runout, and feel of spray in nose/throat; results were reported in the Annals of Allergy, Asthma and Immunology [2004;93:345-50]). In the second part of the study, reported here, discrete choice experiment methodology was used in which the patients chose among hypothetical INS products that differed in the intensity of the 6 sensory attributes and monthly copayments of $15, $30, and $50. Each sensory attribute was characterized by 3 intensity levels, e.g., no aftertaste (mild intensity), weak aftertaste (moderate intensity), or strong aftertaste (severe intensity). The strength of preferences, shown as marginal willingness to pay to avoid certain sensory attributes, was measured in U.S. dollars per month. We also evaluated the effect of annual household income on willingness to pay. RESULTS: Demographic results indicated that 86.7% of participants had prior experience with at least 2 INS products. Seven patients (5.8%) were excluded from the willingness-to-pay analysis due to inconsistent responses to the logic checks used to confirm patient engagement in the study instrument. On average, the 113 remaining patients were willing to pay $11 (95% confidence interval [CI], $9-$13) per month in 2003 dollars to get an INS with no smell instead of strong smell, $12 (95% CI, $10-$14) for no taste instead of strong taste, $20 (95% CI, $18-$22) for no aftertaste instead of strong aftertaste, $10 (95% CI, $9-$12) for no throat rundown instead of a lot of throat rundown, $11 (95% CI, $9-$13) for no nose runout instead of a lot of nose runout, and $6 (95% CI, $4-$8) for a spray with a wet feel instead of a dry feel. Comparing moderate intensity levels of each sensory attribute with the mildest, only 3 attributes had statistically significant willingness to pay: aftertaste, throat rundown, and nose runout. Patients with a higher income were willing to pay more to avoid a lot of throat rundown and nose runout than those with a low income (P less than0.01), but this relationship did not hold for the other sensory attributes. CONCLUSIONS: Patients demonstrated significant willingness to pay to avoid certain sensory attributes of INSs. Sensory attributes of INS products appear to be potentially important considerations when evaluating alternative INS products for drug therapy selection or formulary placement.