PBI19 Cost-Effectiveness Analysis of Adalimumab Biosimilar for Rheumatoid Arthritis in Brazil Compared to Delayed Biologic Treatment Initiation

Abstract

The progression of moderate and severe rheumatoid arthritis (RA) is controlled for many patients by biologic disease modifying anti-rheumatic drugs (bDMARDs). However, some patients face a delay to initiate biologic treatment after becoming eligible for these therapies. The aim of this analysis was to evaluate the economic impact of delaying the start of biologic treatment in a cost-effectiveness model, from a Brazilian private healthcare perspective. A semi-Markov cohort model was developed, based on previously published analyses. The model adopted a cycle length of 6 months and a time horizon of 50 years. Cost and outcomes were discounted at a rate of 5% per year. A sequence of bDMARDs beginning with AMGEVITA™ (adalimumab-atto), an adalimumab biosimilar, was compared to the same sequence in the comparator arm starting with a 6-month delay on originator adalimumab, delay during which patients are assumed to continue on conventional therapy. Patient outcomes were based on Health Assessment Questionnaire (HAQ) scores. Cost inputs were taken from local sources, and comparative efficacy and utility estimates were collected from peer-reviewed literature. For each arm, the model estimates the total direct costs, quality-adjusted life-years (QALYs) and life-years (LYs). The results of the model were used to derive the incremental cost-effectiveness ratio (ICER) and the incremental cost per LY gained. Later treatment initiation on originator adalimumab resulted in total discounted costs of $766,706, 6.96 discounted QALYs and 10.93 discounted LYs. Earlier treatment with AMGEVITA™ resulted in total discounted costs of $570,437, 7.02 discounted QALYs and 10.96 discounted LYs. With a cost reduction of $196,269 and incremental QALYS and LYs of 0.05 and 0.03, respectively, as a result ICER was negative and earlier intervention with AMGEVITA™ dominated later intervention with originator adalimumab. The availability of AMGEVITA™ has the potential to contribute to reducing the treatment costs for RA.