[Cost-effectiveness analysis of peginterferon beta-1a in Italian relapsing remitting multiple sclerosis management]

Sergio Iannazzo, Laura Santoni, Cecilia Saleri, Elisa Puma, Giulia Vestri, Luigi Giuliani, Pier Luigi Canonico, Diego Centonze

DOI: https://doi.org/10.7175/fe.v17i2S.1230

Abstract

BACKGROUND: Peginterferon beta-1a is indicated in adult patients for the treatment of relapsing remitting multiple sclerosis (RRMS). The efficacy and safety of peginterferon beta-1a was demonstrated in the placebo-controlled ADVANCE trial.

OBJECTIVE: The objective of this study was to assess the cost-effectiveness of peginterferon beta-1a as compared with injectable first-line treatments for RRMS in Italy.

METHODS: The cost-effectiveness analysis was developed through a Markov model with lifetime simulation in the perspective of the Italian National Healthcare Service (NHS). It was added an alternative scenario to take into account the Italian societal perspective. Outcomes were measured in terms of life years (LYs), quality adjusted life years (QALYs), lifetime costs and incremental cost-effectiveness ratio (ICER). The natural progression of the disease was informed by the published literature and previously published modelling exercises. The efficacy of treatments was simulated as reduction of disability progression (EDSS) and relapse rate. Efficacy data were derived from a published network meta-analysis. Unit costs were based on current prices and tariffs, and the published literature. A 3.5% discount rate was applied to costs and outcomes. One-way and probabilistic sensitivity analyses were developed and cost-effectiveness acceptability curves generated.

RESULTS: Peginterferon beta-1a was more effective than the comparators in terms of survival (19.94 vs.19.68-19.81 discounted LYs, respectively), and QALYs (9.07 vs. 8.06 and 8.55 discounted QALY, respectively). In the perspective of the Italian NHS, the ICER was € 11,111/QALY vs. interferon beta-1a 30 µg, € 12,604/QALY vs. interferon beta-1a 22 µg, € 10,580/QALY and € 16,702/QALY vs. interferon beta-1b 250 µg and € 22,023/QALY vs. glatiramer acetate 20 mg. Peginterferon beta-1a dominated interferon beta-1a 44 µg. In the societal perspective, peginterferon beta-1a was dominant due to being more effective and with a lower social cost compared to first-line injectable treatments (interferon beta -1a, interferon beta-1b, glatiramer acetate) for RRMS. The outcomes of the sensitivity analyses confirmed the trend of the base case results.

CONCLUSIONS: Peginterferon beta-1a shows a favourable pharmaco-economic profile for the treatment of RRMS. Even if an official threshold for the cost-effectiveness does not exist in Italy, the ICER values obtained were far below the commonly accepted thresholds (30,000-50,000 €/per QALY gained).

[Article in Italian]

Keywords

Cost-effectiveness; Peginterferon beta-1a; Multiple Sclerosis

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