Clinical trial NCT03078309: The Effects of Cannabis on Visual Functions in Healthy and Retinitis Pigmentosa Patients
Official title: A Controlled Study of the Effect of Cannabis on Visual Functions in Healthy Subjects and in Retinitis Pigmentosa Patients
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: EARLY_PHASE1
Conditions: Retinitis Pigmentosa
Retinal Degeneration
Cannabis
Keywords: retinitis pigmentosa
retinal degeneration
cannabis
THC
CBD
electrophysiology
visual functions
eye
retina
Lead sponsor: Hadassah Medical Organization
Sponsor class: OTHER
Collaborators: name: Hebrew University of Jerusalem
First posted: 2017-03-13
Enrollment: 50
Sex: ALL
Minimum age (years): 18
Maximum age (years): 70
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Arm 1 - healthy subjects. Arm 2 - subjects with retinitis pigmentosa All subjects will undergo a full ocular exam and visual functions will be assessed before and after the administration of a single dose of cannabis (THC:CBD 1:40). On the second study day all subjects will receive a single dose of cannabis (THC:CBD 1:1) and undergo the full ocular exam again.
Primary purpose: BASIC_SCIENCE

Brief summary: Medical Marijuana is used widely, and its effects on the visual system and the function of the retina have not been investigated thoroughly. Some evidence suggests that cannabinoids may be beneficial in certain degenerative diseases of the retina.

The purpose of the study is

1. To determine whether cannabis derivatives affect the visual functions in healthy adults
2. To examine the effect of cannabis derivatives on the retina of retinitis pigmentosa patients

Detailed description: Twenty five healthy subjects and 25 retinitis pigmentosa patients will be recruited and will sign an informed consent form. An initial eye exam will include visual acuity and stereo vision, eye movements and eye movement recording, a full slit lamp eye exam, intra-ocular pressure measurement, visual field, OCT and electrophysiology. The subjects will receive a single sublingual dose of cannabis (THC:CBD 1:1, THC 5 mg, or THE:CBD 1:40, THC 5 mg), and will undergo the above examination again. Subjects will be monitored for 5 hours after the administration of cannabis.

Eligibility criteria: Inclusion Criteria:

* consenting adults
* generally healthy with or without retinitis pigmentosa

Exclusion Criteria:

* chronic or acute disease other than retinitis pigmentosa
* use of medication
* congestive heart failure
* recent use of illicit drugs (past month)
* history of drug dependency
* history of psychiatric disorder in subject or immediate relatives
* pregnancy

Primary outcomes:
measure: Electroretinogram (ERG) - acivity of the neural retina mixed cone-rod response, cone flicker, rod response
timeFrame: 3 hours
measure: Electroretinogram (ERG) - acivity of the neural retina cone flicker latency
timeFrame: 3 hours
Secondary outcomes:
measure: Visual acuity
timeFrame: 3 hours
measure: Titmus stereo eye movements
timeFrame: 3 hours
measure: Eye movements
timeFrame: 3 hours
measure: Intra ocular pressure
timeFrame: 3 hours
measure: Macular thickness (OCT)
timeFrame: 3 hours
Other outcomes:
Locations:
city: Jerusalem
country: Israel
facility: Hadassah Medical Center
Study officials:
affiliation: Hadassah Medical Organization
name: Hadas Mechoulam, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lax P, Esquiva G, Altavilla C, Cuenca N. Neuroprotective effects of the cannabinoid agonist HU210 on retinal degeneration. Exp Eye Res. 2014 Mar;120:175-85. doi: 10.1016/j.exer.2014.01.019. Epub 2014 Feb 1.
citation: Russo EB, Merzouki A, Mesa JM, Frey KA, Bach PJ. Cannabis improves night vision: a case study of dark adaptometry and scotopic sensitivity in kif smokers of the Rif mountains of northern Morocco. J Ethnopharmacol. 2004 Jul;93(1):99-104. doi: 10.1016/j.jep.2004.03.029.
citation: Lyons CJ, Robson AG. Retinal Ganglion Cell Dysfunction in Regular Cannabis Users: Is the Evidence Strong Enough to Consider an Association? JAMA Ophthalmol. 2017 Jan 1;135(1):60-61. doi: 10.1001/jamaophthalmol.2016.4780. No abstract available.