Huntington disease (HD) is an inherited degenerative brain disorder characterized by motor abnormalities and dementia produced by selective lesions in the cerebral cortex and, in particular, the striatum. There are presently no known conventional therapies available to alleviate HD symptoms or delay HD-associated striatal degeneration.
Cannabinoids possess various properties that show potential for the treatment of neurodegenerative disorders like Huntington disease,[1-4] and cannabinoid administration has shown efficacy in the treatment of HD in preclinical models[5-7] as well as in case studies.[8-9]
A 2009 randomized controlled trial assessing the use of a synthetic cannabinoid (nabilone) in 44 patients with HD demonstrated behavioral and symptomatic improvements in patients.[10] Two more recent human trials, both involving the use of plant-cannabis extracts (Sativex), have shown mixed results. While one study[11] identified no significant changes in patients’ motor subscores on the Unified Huntington’s Disease Rating Scale, patients participating in a second study did show motor score improvements following the initiation of cannabis therapy.[12]
Most recently, a 2021 literature review of 22 studies assessing the effects of either cannabis or cannabinoids on tremor, spasms, and other HD-related symptoms determined, “[T]he majority of studies showed statistically significant results favoring the use of medical marijuana, especially for improving motor symptoms and quality of sleep.” While acknowledging that further human trials are warranted, authors nonetheless concluded, “[W]e recommend that physicians consider prescribing medical marijuana as an adjunctive treatment for symptomatic relief to slow the progression or reverse spasms, tremor, spasticity, chorea, dystonia, behavioral neuropsychiatric and sleep disturbances in patients with Huntington disease.”[13]
REFERENCES
[1] Luvone et al. 2009. Cannabidiol: a promising drug for neurodegenerative disorders? CNS Neuroscience & Therapeutics 15: 65-75.
[2] Sagredo et al. 2012. Cannabinoids: Novel Medicines for the Treatment of Huntington’s Disease. Recent Patents on CNS Drug Discovery 7: 41-48.
[3] Gowran et al. 2011. The multiplicity of action of cannabinoids: implications for treating neurodegeneration. CNS Neuroscience & Therapeutics 17: 637-644.
[4] Sagredo et al. 2012. Cannabinoids: novel medicines for the treatment of Huntington’s disease. Recent Patents on CNS Drug Discovery 7: 41-48.
[5] Sagredo et al. 2011. Neuroprotective effects of phytocannabinoid-based medicines in experimental models of Huntington’s disease. Journal of Neuroscience Research 89: 1509-1518.
[6] Valdeolivas et al. 2012. Sativex-like combination of phytocannabinoids in neuroprotective in malonate-lesioned rats, an inflammatory model of Huntington’s disease: role of CB1 and CB2 receptors. ACS Chemical Neuroscience 16: 400-406.
[7] Valdeolivas et al. 2017. Effects of a Sativex-like combination of phytocannabinoids on disease progression in R6/2 mice, an experimental model of Huntington’s disease. International Journal of Molecular Sciences 18: 684.
[8] Meisel and Friedman. 2012. Medical marijuana in Huntington’s disease: report of two cases. Medicine and Health, Rhode Island 95: 178-179.
[9] Curtis and Rickards. 2006. Nabilone could treat chorea and irritability in Huntington’s disease. The Journal of Neuropsychiatry and Clinical Neurosciences 18: 553-554.
[10] Curtis et al. 2009. A pilot study using nabilone for symptomatic treatment in Huntington’s disease. Movement Disorders 24: 2254-2259.
[11] Lopez-Sendon Moreno et al. 2016. A double-blind, randomized, cross-over, placebo-controlled, pilot trial with Sativex in Huntington’s disease. Journal of Neurology 263:1390-1400.
[12] Saft et al. 2018. Cannabinoids for treatment of dystonia in Huntington’s disease. Journal of Huntington’s Disease 7: 167-179.
[13] Akinyemi et al. 2020. Medical marijuana effects in movement disorders: Focus on Huntington disease; A literature Review. Journal of Pharmacy & Pharmaceutical Sciences 23: 389-395.