PSY87 - Pegaspargase In The Treatment of Acute Lymphoblastic Leukemia: A CMA Model Demonstrates Its Economic Benefit For The Italian National Health System

Abstract

Pegaspargase is a pegylated form of native E. Coli asparaginase used as an agent in the treatment of acute lymphoblastic leukemia (ALL). Compared to the native form, it presents two main benefits: (i) a longer half-life, thus reducing the number of administrations and (ii) a lower immunogenicity, both in terms of hypersensitivity/allergic reactions as well as antibody formation, thus avoiding to switch to second line costly treatment, such as that with Erwinia Chrisanthemi asparaginase. We present here a cost-minimization analysis (CMA) to show that pegaspargase leads to an economic benefit to the Italian National Health System (SSN). For the model, we constructed a decision tree based upon the clinical practice for the treatment of ALL, with inputs derived from Italian protocols AIEOP-BFM 2009 (for pediatrics) and GIMEMA LAL 1913 (for adults). The native E. Coli asparaginase has been selected as comparator since some patients still use this enzyme in the first-line treatment of ALL. Branch point probabilities representing immunogenic rates were obtained from the best available published literature. Direct costs (hospitalization, drug administration, allergic reactions management) were derived from Gazzetta Ufficiale. Our base-case analysis revealed that the cost-per-patient (both for pediatrics and adults) for pegaspargase was ~6000 € lower than that for native E. coli asparaginase mainly due to the reduced number of administrations and to the lower incidence of immunogenic reactions. The latter has in turn led to a lower hospitalization rate and to a lower switch to the more expensive second line treatment with Erwinia Chrisanthemi. The costs associated with the use of pegaspargase for the first line treatment of ALL are lower than those deriving from the native form of native E. coli asparaginase. Thus, pegaspargase is a cost saving option, with a potential beneficial budget impact for the Italian SSN.