For example, patients with heart disease or stroke who are CYP2C19 poor metabolizers may be prescribed the more expensive ticagrelor in place of clopidogrel (which is metabolized into its active form by CYP2C19).25 Thus, even if genetic information is freely accessible, economic evaluations of PGx testing are still relevant and necessary. This evidence concerns the gene CYP2C19 and Stroke.