ALSUntangled No. 16: Cannabis

Clinical Data for the Use of Cannabis-Based Treatments: A Comprehensive Review of the Literature

Objective:

To compile and synthesize the available literature describing medical cannabis use across various disease states.

Data Sources:

PubMed, EBSCO, and Google Scholar searches were conducted using MeSH and/or keywords.

Study Selection and Data Extraction:

Studies were included if they described the use of cannabis-based products and medications in the treatment of a predefined list of disease states in humans and were published in English. The extraction period had no historical limit and spanned through April 2019.

Data Synthesis:

Evidence was compiled and summarized for the following medical conditions: Alzheimer disease, amyotrophic lateral sclerosis, autism, cancer and cancer-associated adverse effects, seizure disorders, human immunodeficiency virus, inflammatory bowel disease, multiple sclerosis (MS), nausea, pain, posttraumatic stress disorder, and hospice care.

Relevance to Patient Care and Clinical Practice:

Based on identified data, the most robust evidence suggests that medical cannabis may be effective in the treatment of chemotherapy-induced nausea and vomiting, seizure disorders, MS-related spasticity, and pain (excluding diabetic neuropathy). Overall, the evidence is inconsistent and generally limited by poor quality. The large variation in cannabis-based products evaluated in studies limits the ability to make direct comparisons. Regardless of the product, a gradual dose titration was utilized in most studies. Cannabis-based therapies were typically well tolerated, with the most common adverse effects being dizziness, somnolence, dry mouth, nausea, and euphoria.

Conclusions:

As more states authorize medical cannabis use, there is an increasing need for high-quality clinical evidence describing its efficacy and safety. This review is intended to serve as a reference for clinicians, so that the risks and realistic benefits of medical cannabis are better understood.

Study protocol for a randomised, double-blind, placebo-controlled study evaluating the Efficacy of cannabis-based Medicine Extract in slowing the disease pRogression of Amyotrophic Lateral sclerosis or motor neurone Disease: the EMERALD trial

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder with no known cure and with an average life expectancy of 3-5 years post diagnosis. The use of complementary medicine such as medicinal cannabis in search for a potential treatment or cure is common in ALS. Preclinical studies have demonstrated the efficacy of cannabinoids in extending the survival and slowing of disease progression in animal models with ALS. There are anecdotal reports of cannabis slowing disease progression in persons with ALS (pALS) and that cannabis alleviated the symptoms of spasticity and pain. However, a clinical trial in pALS with these objectives has not been conducted.

METHODS AND ANALYSIS

The Efficacy of cannabis-based Medicine Extract in slowing the disease pRogression of Amyotrophic Lateral sclerosis or motor neurone Disease trial is a randomised, double-blind, placebo-controlled cannabis trial in pALS conducted at the Gold Coast University Hospital, Australia. The investigational product will be a cannabis-based medicine extract (CBME) supplied by CannTrust Inc., Canada, with a high-cannabidiol-low-tetrahydrocannabinol concentration. A total of 30 pALS with probable or definite ALS diagnosis based on the El Escorial criteria, with a symptom duration of <2 years, age between 25 and 75years and with at least 70% forced vital capacity (FVC) will be treated for 6 months. The primary objective of the study is to evaluate the efficacy of CBME compared with placebo in slowing the disease progression measured by differences in mean ALS Functional Rating Scale-Revised and FVC score between the groups at the end of treatment. The secondary objectives are to evaluate the safety and tolerability of CBME by summarising adverse events, the effects of CBME on spasticity, pain, weight loss and quality of life assessed by the differences in mean Numeric Rating Scale for spasticity and Numeric Rating Scale for pain, percentage of total weight loss and ALS specific quality of life-Revised questionnaire.

ETHICS AND DISSEMINATION

The study has been approved by the local Institutional Review Board. The results of this study will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03690791.

Effects of cannabinoids in Amyotrophic Lateral Sclerosis (ALS) murine models: a systematic review and meta-analysis

Amyotrophic Lateral Sclerosis (ALS) is a neurodegenerative disorder that results from motor neuron damage. Cannabinoids have been proposed as treatments for ALS because of their anti-excitotoxicity, anti-oxidant and anti-inflammatory effects. Preclinical studies in mice models of ALS have been published using a range of cannabinoid formulations and doses. To date, there has been no rigorous evaluation of these trials to assess a potential cannabinoid treatment effect. This review and meta-analysis was undertaken to provide evidence for or against a treatment effect of cannabinoids in murine ALS models. Evidence of a treatment effect in mice may provide motivation for trials in human ALS. We identified a total of 10 studies; nine studies using cannabinoid treatment in transgenic SOD1-G93A ALS-model mice and one study in TDP-43 transgenic mice. Eight of the nine studies that used SOD1-G93A mice expressed similarly high copy numbers of the transgene while one study used a low-copy number line. Outcomes evaluated were survival time and disease progression. The latter was measured by motor function and bodyweight decline. Meta-analysis of the mean difference in survival time across the seven studies showed an increase in survival of 3.84 days (95% CI: 0.35-7.32 days; p = 0.031) for cannabinoid treated compared to control SOD1-G93A mice. It was not possible to conduct meta-analyses for motor function decline or weight loss. However, eight of nine studies reported significant improvements in measures of motor function decline and one reported non-significant improvements. Weight loss was significantly attenuated in four of five studies reporting this measure while the other study reported a non-significant attenuation. This review provides some evidence for the efficacy of cannabinoids in prolonging survival time in an ALS mouse model. A delay in disease progression is also suggested following cannabinoid treatment though it was not possible to consolidate the results from reviewed studies. However, studies have moderate to high risk of bias and are highly heterogeneous. Although this review provides some evidence to support the conduct of a cannabinoid trial in human ALS, more standardized studies on specific cannabinoids are necessary before supporting therapeutic potential of cannabinoids in treating patients with ALS. OPEN SCIENCE BADGES: This article has received a badge for *Preregistration* because the study was pre-registered at https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=89274. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Read the Editorial Highlight for this article on page 168.

Safety and efficacy of nabiximols on spasticity symptoms in patients with motor neuron disease (CANALS): a multicentre, double-blind, randomised, placebo-controlled, phase 2 trial

BACKGROUND

Spasticity is a major determinant of disability and decline in quality of life in patients with motor neuron disease. Cannabinoids have been approved for symptomatic treatment of spasticity in multiple sclerosis. We investigated whether cannabinoids might also reduce spasticity in patients with motor neuron disease.

METHODS

We did an investigator-initiated, randomised, double-blind, placebo-controlled, phase 2 clinical trial at four tertiary motor neuron disease centres in Italy. Eligible patients were aged 18-80 years; had possible, laboratory-supported probable, probable, or definite amyotrophic lateral sclerosis as defined by revised El Escorial criteria, or primary lateral sclerosis according to Pringle's criteria; had spasticity symptoms due to motor neuron disease for at least 3 months; had spasticity scores of 1 or greater in at least two muscle groups on the Modified Ashworth Scale; and were taking an antispasticity regimen that was maintained at a stable dose for 30 days before enrolment. Participants were assigned (1:1) by an independent statistician via a computer-generated randomisation sequence to a standardised oromucosal spray (nabiximols) containing a defined combination of delta-9-tetrahydrocannabinol and cannabidiol (each 100 μL actuation contained 2·7 mg delta-9-tetrahydrocannabinol and 2·5 mg cannabidiol) or to placebo for 6 weeks. Participants self-titrated during the first 14 treatment days according to a predefined escalation scheme (maximum 12 actuations per 24 h), then maintained that dose for 4 weeks. The primary endpoint was the change in the score on the Modified Ashworth Scale, which was assessed at baseline and after 6 weeks. Safety and tolerability were also monitored. Participants, investigators, site personnel, and the study statistician were masked to treatment allocation. All randomised participants who received at least one dose of study drug were included in the analysis. This trial is registered with ClinicalTrials.gov, number NCT01776970. The trial is closed to new participants with follow-up completed.

FINDINGS

Between Jan 19, 2013, and Dec 15, 2014, 60 participants were randomly assigned, and 59 participants were included in the final analysis (29 in the nabiximols group and 30 in the placebo group). Modified Ashworth Scale scores improved by a mean of 0·11 (SD 0·48) in the nabiximols group and deteriorated by a mean of 0·16 (0·47) in the placebo group (adjusted effect estimate -0·32 [95% CI -0·57 to -0·069]; p=0·013). Nabiximols was well tolerated, and no participants withdrew from the double-blind phase of the study. No serious adverse effects occurred.

INTERPRETATION

In this proof-of-concept trial, nabiximols had a positive effect on spasticity symptoms in patients with motor neuron disease and had an acceptable safety and tolerability profile. These findings should be investigated further in larger clinical trials.

FUNDING

Italian Research Foundation for Amyotrophic Lateral Sclerosis.

Exploring targets and therapies for amyotrophic lateral sclerosis: current insights into dietary interventions

A growing number of preclinical and human studies demonstrate a disease-modifying effect of nutritional state in amyotrophic lateral sclerosis (ALS). The management of optimal nutrition in ALS is complicated, as physiological, physical, and psychological effects of the disease need to be considered and addressed accordingly. In this regard, multidisciplinary care teams play an integral role in providing dietary guidance to ALS patients and their carers. However, with an increasing research focus on the use of dietary intervention strategies to manage disease symptoms and improve prognosis in ALS, many ALS patients are now seeking or are actively engaged in using complementary and alternative therapies that are dietary in nature. In this article, we review the aspects of appetite control, energy balance, and the physiological effects of ALS relative to their impact on overall nutrition. We then provide current insights into dietary interventions for ALS, considering the mechanisms of action of some of the common dietary interventions used in ALS, discussing their validity in the context of clinical trials.

Complementary and Alternative Therapies in Amyotrophic Lateral Sclerosis

Given the severity of their illness and lack of effective disease-modifying agents, it is not surprising that most patients with amyotrophic lateral sclerosis (ALS) consider trying complementary and alternative therapies. Some of the most commonly considered alternative therapies include special diets, nutritional supplements, cannabis, acupuncture, chelation, and energy healing. This article reviews these in detail. The authors also describe 3 models by which physicians may frame discussions about alternative therapies: paternalism, autonomy, and shared decision making. Finally, the authors review a program called ALSUntangled, which uses shared decision making to review alternative therapies for ALS.

Medical marijuana in neurology

Constituents of the Cannabis plant, cannabinoids, may be of therapeutic value in neurologic diseases. The most abundant cannabinoids are Δ(9)-tetrahydrocannabinol, which possesses psychoactive properties, and cannabidiol, which has no intrinsic psychoactive effects, but exhibits neuroprotective properties in preclinical studies. A small number of high-quality clinical trials support the safety and efficacy of cannabinoids for treatment of spasticity of multiple sclerosis, pain refractory to opioids, glaucoma, nausea and vomiting. Lower level clinical evidence indicates that cannabinoids may be useful for dystonia, tics, tremors, epilepsy, migraine and weight loss. Data are also limited in regards to adverse events and safety. Common nonspecific adverse events are similar to those of other CNS 'depressants' and include weakness, mood changes and dizziness. Cannabinoids can have cardiovascular adverse events and, when smoked chronically, may affect pulmonary function. Fatalities are rare even with recreational use. There is a concern about psychological dependence, but physical dependence is less well documented. Cannabis preparations may presently offer an option for compassionate use in severe neurologic diseases, but at this point, only when standard-of-care therapy is ineffective. As more high-quality clinical data are gathered, the therapeutic application of cannabinoids will likely expand.