Example 9
The following example provides details of a study used to determine whether pimavanserin or ketanserin induced changes in subjective experience during psilocybin therapy are due to changes in 5-HT2A occupancy. If not, downstream molecular and cellular effects that may be important in psilocybin's therapeutic effects may be preserved after co-treatment with a 5-HT2A specific antagonist and/or inverse agonist.
In this study, [11C]CIMBI-36 (a selective 5-HT2A receptor agonist positron emission tomography (PET radioligand) will be used to investigate whether 5-HT2A binding is affected by placebo vs. pimavanserin or ketanserin
At time t=0, subjects will be administered 25 mg psilocybin (PSI) in combination with either a placebo, or a low or high dose of pimavanserin or ketanserin. At t=2 hours, subjects will be given a tracer dose of [11C]CIMBI-36. At t=2-3 hours, a PET scan will be performed, to determine whether 5-HT2A binding is affected by either dose of pimavanserin or ketanserin.
