Presentation (CTI)

OBJECTIVES: Utilities quantify quality-adjusted life years (QALYs) in economic models. Most models apply generic health-state utilities, assuming identical quality of life regardless of treatment. This undervalues innovative therapies versus non-targeted options (corticosteroids, NSAIDs, antibiotics) that control disease but add chronic side effects. Treatment-specific utilities capture real patient experience improvements yet face CDA-AMC, NICE and private-payer concerns over consistency and bias, and prefer generic health state utilities unless in the case of NICE treatment effects are robust and externally validated.
METHODS: We illustrate the consequences of applying generic versus treatment-class-specific utilities over 5-years using published transition probabilities in a simulation based on Crohn’s disease. Two scenarios were tested: (1) generic utilities by health state and (2) class-specific utilities assigning distinct HRQoL for biologics versus conventional care from published sources. This approach avoids the bias of naïvely comparing utilities across individual treatments from disparate sources while preserving meaningful differences in patient experience between therapeutic classes.
RESULTS: Generic utilities yielded a 5-year incremental gain of 0.21 QALYs for biologics. Class-specific utilities raised the gain to 1.39 QALYs, a 1.17-QALY increase likely to shift incremental cost-effectiveness ratios and reimbursement decisions. Generic values missed persistent side effects—mood swings, weight gain, fatigue—common with conventional drugs yet rarely coded as adverse events, and thus invisible to short disutility adjustments.
CONCLUSIONS: Models relying solely on generic utilities systematically favour cheaper regimens by ignoring cumulative tolerability costs. Adverse event disutilities help but cannot capture pervasive, low-grade harms. Class-specific utilities, derived from validated HRQoL data, offer a feasible compromise: they respect HTA consistency by grouping treatments yet credit targeted agents for superior day-to-day life. Our Crohn’s example—biologic remission versus steroid-managed remission—shows class utilities capture important QALY benefits, altering pricing negotiations. Broader adoption would align evaluations with patient experience without introducing the biases that concern CDA-AMC and NICE.