The Effect of Dronabinol on Ocular Hemodynamics in Patients With Primary Open Angle Glaucoma
Status:
Recruiting
Trial end date:
2023-10-20
Target enrollment:
Participant gender:
Summary
Glaucoma is among the leading causes for irreversible blindness worldwide. While lowering
intraocular pressure (IOP) remains the mainstay of therapy, there are still some patients who
progress despite well-controlled IOP. There is evidence from several studies that ocular
blood flow and its regulation is impaired in patients with glaucoma. Tetrahydrocannabinol
(THC) has been used in the treatment for glaucoma in some countries for several years due to
its IOP lowering effect. In addition, there is also evidence that THC features
neuroprotective effects and improves ocular hemodynamics. Dronabinol is a synthetic THC that
is legally available in several European countries. It has the advantage that exact dosing of
THC is possible in contrast to previously applied administration forms such as smoking. Due
to its legal status in the past, data about the effect of THC on ocular blood flow and its
regulation are sparse. In a recent study conducted in the investigators laboratory they found
that single administration of dronabinol leads to a significant increase in optic nerve head
(ONH) blood flow without impairing its autoregulatory capacity.The aim of the present study
therefore is to investigate whether single administration of dronabinol alters optic nerve
head (ONH) blood flow in patients with open angle glaucoma. In addition, other parameters for
ocular blood flow will be measured, in particular retinal blood flow, retinal oxygen
saturation and retinal neurovascular coupling. The study will be conducted in a
parallel-group, randomized, double-masked, placebo-controlled, cross-over design. Patients
will be randomized to either receive 5mg or 10mg dronabinol on one study day. Other studies
investigating retinal hemodynamics or IOP after administration of THC also have used similar
or slightly higher doses.