Cost analysis of ADRB2 genotype-guided treatment for childhood asthma: results of the PUFFIN and PACT trial

<bold>Background:</bold> Long-acting β2-agonists (LABA) are commonly used to treat asthma, however, some children do not respond well to LABA, possibly due to the Arg16Gly polymorphism in the ADRB2 gene encoding the β2 receptor, in particular the rs1042713 A allele (Arg16 amino acid). Arg16Gly ADRB2 genotype identification to guide treatment step-up decisions in children with uncontrolled asthma despite low dose inhaled corticosteroids (ICS) may reduce asthma exacerbations. Here, we investigated whether ADRB2 genotype-guided treatment is cost saving. <bold>Methods:</bold> Total semiannual healthcare costs for children with and without exacerbations were calculated using PUFFIN trial data. 102 Dutch and Swiss children were randomised to a genotype-guided treatment arm (adding LABA (Gly16Gly) or double dose ICS (Arg16Arg/Arg16Gly)) and control arm where children were randomised to LABA or double dose ICS. Thereafter, we used exacerbation rates of PUFFIN and PACT to calculate asthma-related healthcare costs per treatment arm as PACT closely matches the design of PUFFIN. The PACT trial randomised 91 children from Scotland and England with uncontrolled asthma to a genotype-guided treatment arm (LABA (Gly16Gly) or montelukast (Arg16Arg/Arg16Gly)) and control arm (LABA or montelukast). <bold>Results:</bold> Overall mean costs per child were €771.07 (range €616.86-925.28) in the genotype-guided treatment arm (23 of 90 children experienced exacerbations) and €827.31 (range €661.85-992.77) in the control arm (40 of 103 experienced exacerbations). <bold>Conclusion:</bold> ADRB2 genotype-guided treatment reduces asthma exacerbations and is cost saving, outweighing the screening costs.