Yes, there has been research on nabilone, which is a synthetic THC analogue. You heard Dr. Zhang mention before that it is a strong agonist, so it has very strong binding to the receptors, which is different from the natural form of THC you'll find in the plant, which is a weak agonist.
We do have clinical trials of nabilone for the indications that you've mentioned. There is moderate quality evidence of effectiveness, which is why it was approved. What we now need to understand is if there is a different therapeutic effect between the synthetic THC analogues versus the products you're finding more in the natural cannabis that's more readily available now.