Data from the Open Targets resource (www.opentargets.org/) suggest that 49 drugs have reached phase IV investigation for DRD2 across a range of indications, including mental health disorders and cocaine dependence; no drugs are in development for ADH1B, KLB, GCKR, or SLC39A8. FGF21 has been explored due to links with KLB, but no drugs are in the market yet. The gene discussed is FGF21; the disease is cocaine dependence.