This 2009 double-blind, randomized, placebo-controlled, parallel-group clinical trial aimed to compare the efficacy, safety, and tolerability of THC:CBD extract and THC only extract with placebo in relieving pain in patients with advanced cancer who had inadequate pain relief with strong opioids like morphine. The study found that THC:CBD extract is effective in relieving pain in patients with advanced cancer who do not achieve sufficient pain relief from strong opioids.
Cancer-related pain affects a significant number of patients, with some experiencing inadequate relief from opioids and standard pain relievers. Cannabis compounds, such as tetrahydrocannabinol (THC) and cannabidiol (CBD), have shown potential in alleviating cancer pain.
In total, 177 patients participated in the two-week trial. These individuals experienced inadequate pain relief despite chronic opioid dosing, with morphine being the primary opioid used. Despite the various treatment groups, the amount of their regular pain medicine and the number of times extra pain medicine was needed remained the same. The primary analysis revealed a statistically significant improvement in mean pain scores for THC:CBD extract compared to placebo, while the THC extract did not show a significant change. Additionally, twice as many patients in the THC:CBD group achieved a reduction of more than 30% in pain scores compared to placebo. Adverse events were typically mild to moderate in severity.
The patients were administered the medication using a pump action oromucosal spray. Each 100-μL (0.1ml) actuation of the THC:CBD extract spray delivered a dose containing 2.7mg THC and 2.5mg CBD, roughly a 1:1 THC:CBD ratio. The THC extract spray contained 2.7mg THC per actuation. In comparison, placebo actuations contained no cannabinoids and only excipients and colorants. The maximum permitted dose of all study medication was eight actuations in any three-hour period (totaling up to 21.6mg THC and 20mg CBD) and 48 actuations in any 24-hour period (totaling up to 64.8mg THC and 60mg CBD).
Patients self-titrated their optimal dose over the course of the first week, gradually increasing the total number of sprays by a maximum of 50% daily until they achieved satisfactory pain relief or experienced unwanted effects. By the end of the first week, the mean number of sprays per day stabilized. The THC:CBD group averaged 8.75 sprays, equivalent to a daily dosage of approximately 23.6mg THC and 21.9mg CBD. The THC group averaged 8.34 sprays, corresponding to a daily dosage of approximately 22.5mg THC. In comparison, the placebo group averaged 9.61 sprays, which contained no active cannabinoids but included excipients and colorants.
It's important to note that relatively low doses of THC and CBD were utilized in this study, which may differ from the dosing recommendations typically suggested by experts in the field of cannabinoid-based cancer treatments. These experts often advocate for higher doses to potentially maximize therapeutic benefits. However, despite the use of lower doses in this study, the results still demonstrated positive outcomes in pain relief for patients with advanced cancer that even strong opioids could not help with. The THC-only group did not show significant changes in pain reduction, which may be attributed to the relatively low dose of THC administered.
The dosing regimen was well-tolerated, and patients maintained stable dosing throughout the treatment period. The specific dosages of THC and CBD delivered through the oromucosal spray allowed for individualized and flexible dosing based on patients' response and tolerance to the medication.
The THC:CBD extract group demonstrated a significant reduction in pain severity compared to the placebo group, as evidenced by a decrease of 1.37 points on the Numerical Rating Scale (NRS). Twice as many patients in the THC:CBD group achieved a 30% or greater improvement in pain scores compared to placebo. The THC extract group did not show a statistically significant change in pain scores.
The THC:CBD and THC medications were generally well tolerated, with the most common adverse events being somnolence, dizziness, and nausea, mostly of mild or moderate severity. No safety concerns were identified, and the incidence of serious adverse events was similar across the treatment groups. The study population had advanced cancer, and mortality during the study period was primarily due to disease progression.
The results suggest that THC:CBD extract is an effective adjunctive treatment for cancer-related pain in patients who have inadequate pain relief with opioids. The combination of THC and CBD appears to have a more promising efficacy profile than THC alone, possibly due to synergistic effects and the modulation of unwanted effects by CBD.
Despite the clear and repeated scientific evidence from this study and many others on the topic that THC:CBD extract provides a potentially stronger and more efficient alternative for pain relief than toxic synthetic opioids, it is disheartening that the medical community has made little progress in adopting this alternative approach today, over a decade after this study was published. The continued preference for toxic synthetic opioids over safe and natural phytocannabinoids disregards the potential benefits and safer profile offered by cannabinoid-based therapies. This resistance underscores the importance of promoting greater awareness, education, and a progressive mindset within the medical field, emphasizing the need to bridge the gap between scientific findings and clinical practice through further education and awareness initiatives.
The results of this study, conducted in 2009, provide strong evidence that THC:CBD extract is effective in relieving severe cancer-related pain. It is unfortunate that despite such favorable outcomes and decades of research on the topic, the medical establishment is still resistant to embracing cannabis as a viable alternative to toxic synthetic opioids. This study highlights the urgent need for further investigation and a more open-minded approach to incorporating cannabinoids-based medications into pain management strategies.
Study Title: Multicenter, double-blind, randomized, placebo-controlled, parallel-group study of the efficacy, safety, and tolerability of THC:CBD extract and THC extract in patients with intractable cancer-related pain
Study Link: https://pubmed.ncbi.nlm.nih.gov/19896326