Every therapeutic potential of plants and natural products should be carefully researched and if proven safe and effective in certain conditions, made available to the public - also when it derives from a forbidden substance, whatever the reason of the prohibition.
This is self-evident, or it should be, but in a number of instances, there are indications that no sufficient research is being done into potential therapeutic applications, and that promising trials are being obstructed. Some of these instances are: cannabis, MDMA and other "psychedelic" substances, such as iboga, ayahuasca, LSD, but also coca leaves or amphetamine.