Are There Clinical Trials on Cannabis for Ankylosing Spondylitis? 

The chronic inflammatory disease known as ankylosing spondylitis (AS) makes the sacroiliac joints and spine painful and stiff. The use of medical cannabis as a possible treatment has gained popularity in recent years. However, the fundamental question still stands: have clinical trials tested cannabis specifically in AS patients? 

The current situation is examined in this article, which includes information on available clinical trial data, analysis of results, research obstacles, and useful advice for patients and physicians. 

 Why Clinical Trials Matter in AS Treatment 

In medicine, clinical trials are the gold standard. They assist in determining whether a treatment is safe for a variety of populations in addition to being effective. Evidence is ranked in a hierarchy: case reports and anecdotal accounts sit at the bottom, while randomised controlled trials (RCTs) and systematic reviews offer stronger validation.  

 High-quality trials aid in better decision-making for both patients and clinicians by directing dosage, duration, side-effect profiles, and possible interactions. Cannabis stays in the experimental and supplemental care category in the absence of RCTs.  

 Cannabis in Chronic Pain and Arthritis Research 

Cannabis has been investigated under various circumstances, providing insightful oblique information: 

• Studies on neuropathic pain and chronic back pain have found that cannabinoid-based drugs can reduce pain to a moderate degree. 

• In small-scale studies, rheumatological and arthritis conditions, including fibromyalgia and rheumatoid arthritis, have shown improved sleep and lower pain scores. 

• THC and CBD may alter inflammatory pathways associated with autoimmune diseases, according to preclinical research, which includes animal models. 

Although these results are part of larger cannabis studies, caution must be used when extrapolating them directly to AS. Because AS has a distinct pathology that involves sacroiliac joint involvement and spinal fusion, specialised trials are necessary. 

 Current Clinical Trials Focused on AS and Cannabis 

Few studies specifically address cannabis treatment in AS when looking through clinical trial registries (like ClinicalTrials.gov and EUCTR):  

• Pilot studies that have been completed have looked at THC or THC/CBD combinations in mixed cohorts that include people with rheumatoid arthritis, AS, and other chronic pain conditions. Although the results were statistically underpowered, often with fewer than 50 AS participants, they tended to concentrate on pain relief and mobility improvements. 

• No AS-specific subgroup data was reported in a small, randomised crossover trial that compared a synthetic THC formulation to a placebo while also combining AS with more general inflammatory conditions. 

• In order to compare THC/CBD oral oils to a placebo over a period of 12–16 weeks, a few ongoing UK trials are currently seeking participants with axial spondyloarthritis (the more general disease classification that includes AS). Results are anticipated from these by the end of 2025. 

As a result, clinical trials of cannabis that are specifically targeted at AS are still rare, though they are becoming slightly more prevalent within larger inflammatory joint studies that fall under the AS treatment trial research category. 

What the Evidence Shows So Far 

Despite these drawbacks, some initial results are showing up: 

•  Pain scores: Although placebo effects cannot be ruled out, many participants report a slight improvement (10–30% reduction on visual analogue scales). 

• Sleep quality: 40–60% of participants in mixed arthritis cohorts, including those with AS, reported improvements in their sleep. 

• Inflammatory markers: CRP and ESR were not directly measured in many trials; when they were, the results were inconsistent and not statistically significant. 

• Quality of life: Due to small sample sizes, it is impossible to conclusively link cannabis too small to moderate improvements on measures like the SF-36. 

Although the data is still preliminary and inconsistent, overall, it offers a cautiously positive signal. The intricacy is increased by the small sample sizes, differences in dosage, product kinds, and delivery systems. Instead of being definitive proof, the results are best interpreted as medical cannabis evidence.  

 Challenges in Researching Cannabis for AS 

Several key barriers hinder progress: 

• Regulatory hurdles: Because cannabis is a controlled substance, the approval, manufacturing, and importation procedures are made more difficult 

• Funding shortages: Private investors risk stigma or a low market return, and public agencies frequently give priority to traditional drug trials. 

• Product inconsistency: Standardisation is challenging due to variations in plant strains, THC/CBD ratios, and formulations. 

• Ethical concerns: There is a lack of long-term safety data, and blinding is still difficult. 

Due to these obstacles, well-organised clinical trials of cannabis move more slowly, which makes it challenging to conduct AS research on cannabis. 

 What Researchers and Rheumatologists Say 

Important voices from organisational and clinical viewpoints include: 

• Until more high-quality trials are conducted, the British Society for Rheumatology (BSR) notes that there is insufficient data to recommend cannabis.  

• Due to a lack of evidence, NICE guidelines in the UK do not currently recommend cannabis for AS. 

• Rheumatologists frequently exhibit cautious curiosity, acknowledging patient interest while highlighting careful risk-benefit analysis and close observation. 

• While highlighting the anti-inflammatory properties of cannabis, some researchers also stress the need for larger Phase II/III studies. 

Certain statements or viewpoints emphasise the importance of exercising caution when interpreting preliminary research and ensuring that ongoing trials are monitored by experts.  

 What Patients Should Know 

Here are some things to consider if you’re thinking about using cannabis for AS: 

• There is little and changing evidence from clinical trials. The effectiveness of cannabis for AS has not been specifically confirmed by any large-scale RCT. 

• Formulation and dosage are important. The THC/CBD ratios of oils, capsules, and vapourised flower are not interchangeable. 

• Expert advice is crucial. Consult a general practitioner or rheumatologist who is knowledgeable about cannabinoids, dosage, and monitoring. 

• There are access and legal limitations. AS is rarely prescribed by the NHS in the UK. Usually, access necessitates private clinics, which are expensive. 

• Updates from ongoing trials might soon provide more accurate advice. In the next 18 to 24 months, keep an eye on registries for new studies that are specific to AS.  

 Final Thoughts 

Although there is currently a dearth of focused, high-quality clinical trials of cannabis for AS, it has shown early mixed promise in treating chronic pain and arthritis-related symptoms. The results of existing research are often inconclusive because they typically use small sample sizes and combine AS with other conditions. 

For patients and clinicians, the bottom line is clear: 

• Cannabis shouldn’t be used as a main treatment but rather as a possible adjunct. 

• With professional supervision and complete knowledge of dosages, product sourcing, and legal constraints, decisions ought to be made on an individual basis.  

• Keep an eye out for new AS research findings and emerging trials, as these could soon provide more precise clinical recommendations. 

Standard AS treatments, such as NSAIDs, physiotherapy, and NHS-approved biologics, continue to be the most reliable evidence-based basis for managing this illness until that time. 

It’s crucial to understand that the effects of medical cannabis for ankylosing spondylitis (AS) vary across individuals. If you’re interested in exploring cannabis for AS as a treatment option, always consult a healthcare provider for advice tailored to your specific needs and condition. 

Learn more or book a medical cannabis consultation at LeafEase