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A call for cannabis research reform in New Zealand: Why real world evidence and patients’ voices matter

New Zealand Flag flying in the wind

Dr Fiona Hutton Associate Professor at the Institute of Criminology Director Te Herenga Waka – Victoria University, Wellington

Dr Geoff Noller Bioethics Department, Dunedin School of Medicine, University of Otago, Dunedin

Alice McSherry Doctoral Candidate at the School of Environment, University of Auckland

While cannabis based medicines hold out the promise of much needed relief, at the same time, this often conflicts with many countries’ drug laws and the dogma of prohibition.  Centuries of stigma around cannabis (and other drug use) has muddied the waters and made it incredibly difficult to progress an accessible and affordable therapeutic cannabis scheme. That cannabis was placed into schedule one/Class A when drug laws like the New Zealand 1975 Misuse of Drugs Act (MoDA) were enacted and therefore cited as having ‘no medical benefit’ has also significantly hampered the development of research about its therapeutic uses (Schlag & Nutt, 2022). 

In New Zealand, cannabis for therapeutic purposes was first made available in 2010, although under strict guidelines – approval was required from the Minister of Health to prescribe. In 2017, cannabidiol (CBD) products containing non-psychoactive cannabis compounds were able to be prescribed more widely by general practitioners (GPs) – although approval was still required by the Ministry of Health to prescribe from 2017 until 2020. It took a further three years for products containing tetrahydrocannabinol (THC), the principal psychoactive cannabis compound, to be prescribed by GPs without government approval. For people living with painful, chronic conditions, this has been an awfully long time to wait.

The Misuse of Drugs (Medicinal Cannabis) Amendment Act of 2018 and the 2020 Medicinal Cannabis Scheme (MCS) should mean therapeutic cannabis products are available and accessible in New Zealand (NZ). However, access to cannabis for therapeutic purposes remains problematic due to the cost of prescribed cannabis products and the reluctance of GPs to prescribe them. This is in part the result of scepticism about the efficacy of cannabis (Rychert et al., 2021, 2020; Nutt et al., 2020; Oldfield et al., 2020), alongside the complex regulatory and compliance scheme accompanying the new 2020 regulations (Ministry of Health, 2022a, 2022b, 2022c). Those who have no option other than to access therapeutic cannabis via ‘Green Fairies’ [1]in the underground illicit market risk prosecution and criminalisation. Under the Misuse of Drugs (Medicinal Cannabis) Amendment Act of 2018, only those who are terminally ill are exempt from prosecution for cannabis offences. A recent scoping document for the review of this amendment in 2021 stated, “The review will not consider widening the exemption to medical uses other than palliation or to other drugs controlled by the Act” (RNZ, 2021) -the government refused to discuss widening the parameters to patients other than those that were terminally ill.     

Using cannabis for therapeutic purposes is often fraught with tensions, and these tensions are exacerbated by debates about what counts as ‘evidence’ when evaluating the efficacy of therapeutic cannabis. The position of Pharmac, New Zealand’s drug funding agency, namely that they will not fund cannabis-based products due to ‘lack of evidence in the form of randomized clinical trials’ (RCTs) (, is a barrier that will be difficult to overcome. That being said, although lack of evidence of the efficacy of cannabis from RCTs is often cited as a reason not to act, Pratt et al. (2019, cited in Ruheel et al., 2021), note there have in fact been several randomised clinical trials (RCTs) examining the use of cannabis for treating conditions, such as fibromyalgia, epilepsy, traumatic brain injury, and that there is,

‘substantial evidence of the efficacy of cannabis in treating conditions including chronic pain and substantial evidence for the efficacy of MC [medicinal cannabis] in treating conditions including chronic pain and multiple sclerosis-related spasticity with conclusive or limited evidence for symptoms such as cancer-related nausea’ (Ruheel et al., 20221, p.2)

Other studies have also noted the efficacy of cannabis in treating chronic pain (Piper et al., 2017; Pergolizzi et al., 2018). A recent systematic review concluded that cannabis products containing THC and CBD may be associated with short-term improvements in chronic pain, although side effects of dizziness and sedation were also noted (McDonagh et al., 2022). The National Academies of Sciences, Engineering and Medicine (2017) found substantial evidence that cannabis is effective for the treatment of chronic pain and that it can also help with sleep disturbance, fibromyalgia and multiple sclerosis.

In the New Zealand context, despite this growing body of evidence, until RCTs can be devised using plant-based products, there appears to be something of an impasse. However, as noted by Schlag et al., (2022) there are some limitations in using RCTs to examine the efficacy of cannabis products, and, without the likelihood of future commercial markets, pharmaceutical companies and other funding bodies are unlikely to support RCTs for therapeutic cannabis products. In addition, there also appears to be a lack of political will to tackle problems with the current medicinal cannabis system. That the evidence noting the efficacy of cannabis-based products is often sidelined is all the more frustrating because the real-world evidence for the effectiveness of cannabis in treating a number of conditions is also growing steadily, both in New Zealand and in places like the UK, Canada, the US, Australia and Germany.

Our exploratory study had the aim of adding to the growing body of ‘real world evidence’. We conducted 26 qualitative interviews with people using therapeutic cannabis products and sent out a survey via a ‘green fairy’ patient list and a legal cannabis clinic website. All participants had clinically diagnosed conditions. Listening to stories of painful, highly complex medical conditions (e.g. cancer, traumatic brain injury, seizures, osteoarthritis, Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS)), futile efforts to control pain with several different opiate-based drugs (e.g. Tramadol) that left people feeling like zombies, was hard. However, hearing how using cannabis products allowed people to cut down or, in some cases, completely stop the use of painkillers and other drugs with debilitating side-effects (addiction, sluggishness, night terrors, tiredness, emotional numbness) was incredibly positive. Those who took part in the project talked about cannabis products as a ‘miracle’, a ‘life saver’ – literally, as some were so overwhelmed by living a life with chronic pain that they sought to end it.  For parents whose children suffered from medical conditions that were difficult to deal with, who saw their children live through multiple seizures and their debilitating effects, using cannabis products enabled ‘normal’ lives to be lived and suffering to be eased. One parent described her son as a ‘totally different child’ after therapeutic use of cannabis dramatically improved his social skills and reduced anxiety and behavioural problems at school – the relief in her tone and on her face was palpable. Yet all these stories – these ‘miracles’ – exist on the margins, in the shadows, on the side-lines, as cannabis products are often unattainable for many apart from on the underground illicit market. ‘Green fairies’ provide access for such patients under constant threat of criminalisation, of losing their homes and freedom – a new approach is sorely needed.

***The term “Green Fairy” refers to those who grow cannabis illegally and provide therapeutic cannabis or cannabis products. The nature of the illicit market and the diversity of expertise among green fairies means that cannabis products sourced from the illicit market may be of variable quality (Raymond et al., 2021) and that “patients” may not always receive informed health advice.

The first publication from this study focused on a thematic analysis of the open-ended survey questions (213 participants in total) exploring whether cannabis products helped people with their health issues/conditions and what the positive and negative effects were of using cannabis therapeutically. Some important issues related to therapeutic use of cannabis were outlined in our article.

Firstly, the majority of those taking part in the survey (95.6% n= 197) said that cannabis had helped them with a variety of conditions e.g., pain related conditions, sleep problems, mental issues such as anxiety and depression, attention deficit hyperactivity disorder (ADHD), autism, post-traumatic stress disorder (PTSD) leukaemia, and addiction issues. The three top issues or conditions that cannabis was effective at helping with were pain relief, anxiety and difficulty sleeping. Participants also noted mainly positive effects from using therapeutic cannabis products with unexpected positive effects also noted in addition to the initial reason/s why participants started using cannabis products. Participants highlighted that their wellbeing and quality of life improved after using cannabis products,

[Cannabis] Helps with literally everything. Every issue I had has been resolved by using cannabis [. . .] eat without feeling sick, sleep better. Helps me calm down when I’m stressed. Because it has done all these things, I am feeling less depressed, even though I have been struggling with depression for years. It’s improved my life so much.’

Others noted in relation to pain relief specifically how much cannabis products had helped them,

‘Helped with my stress and anxiety and depression and most importantly pain relief. It saved my life.’

‘It helped with my pain immensely and helped with my sleep – it was a life saver as I was ready to finish my life before that. I had had enough’.

Secondly of note was the decreased use of prescription medications in the survey data. Stopping use of all medications was the top theme across the thematic analysis [i.e., 49% (n = 76) of the 155 participants answering the question:Has your use of prescribed medicines such as Tramadol/sleeping pills changed e.g., decreased/increased after cannabis consumption for therapeutic purposes?” had stopped or reduced other prescription medications]. This is an important finding, that participants in this New Zealand study in some cases were able to stop completely the use of (mainly) opioid-based medications. Participants also noted that their prescribed medicines often had debilitating side effects such as nausea, as well as providing serious risk of dependence and cognitive impairment. International research finds that cannabis can be effective in treating pain, and sleep disturbance, as well as conditions like epilepsy and multiple sclerosis, with “Project Twenty21” noting pain to be the most common condition cannabis was used to treat followed by anxiety disorders (Sakal et al., 2022). This exploratory New Zealand study adds to the RWE base about the efficacy of therapeutic cannabis use. Coupled with international (Pratt et al., 2019; Piper et al., 2017; Pergolizzi et al., 2018; McDonagh et al., 2022) and previous New Zealand research (Rychert et al., 2020; Armour et al., 2021; Gulbransen et al., 2020), the largely positive experiences of the participants may give GPs and other New Zealand health professionals some confidence that cannabis products could be helpful for their patients.

What is clear from the analysis is that a new way forward is needed to make therapeutic cannabis products accessible and available for those who might benefit. Currently the system, despite amendments, is not working as it should, with price being a prohibitive barrier for many patients. Decriminalisation of ‘green fairy’ products, from growing through to product development, is urgently needed, as well as a fresh approach to the existing system. Clinical trials are needed to develop the New Zealand evidence base for the efficacy of therapeutic cannabis products, and the impasse that we are currently in needs to be broken. Patients’ experiences and voices should not be discounted simply because they are not part of RCTs, especially given the some of the limitations of RCTs in relation to cannabis (Schlag et al., 2021; Nutt, 2022; Piper et al., 2017). The value of RWE, alongside RCTs, increasingly recognised internationally, needs to be incorporated into discussions around the future of therapeutic cannabis consumption.


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