To ascertain whether ezutromid is an AhR agonist or antagonist, the effects of ezutromid on mRNA expression of AhR and AhR‐responsive genes Cyp1b1 and the AhR repressor (AhRR) were assessed in mdx mice and human DMD myoblasts by RT‐qPCR (Figure 5 a). Here, AHRR is linked to Duchenne muscular dystrophy.