The runners have not made such a decision yet. The RCI a non-breed specific group has proposed a rule within five years to ban all drugs from race horses. While certain races can have in their conditions banning the use of certain drugs, such as the Hambletonian banning the use of Lasix, it is up to the individual racing states to pass rules outlawing drugs in race horses. The RCI supporting such a rule is important, but not a guarantee it happens.
Hence, other than the USTA passing a model rule outlawing the use of drugs; they have no say over it.