Medicinal Cannabis (MedCan 3): a randomised, multicentre, double-blind, placebo-controlled trial to assess THC/CBD (1:20) to relieve symptom burden in patients with cancer-a study protocol for a randomised controlled trial.

BACKGROUND: Distressing symptoms are common in advanced cancer. Medicinal cannabinoids are commonly prescribed for a variety of symptoms. There is little evidence to support their use for most indications in palliative care. This study aims to assess a 1:20 delta-9-tetrahydrocannabinol/cannabidiol (THC/CBD) cannabinoid preparation in the management of symptom distress in patients with advanced cancer undergoing palliative care. METHODS AND DESIGN: One hundred and fifty participants will be recruited across multiple sites in Queensland, Australia. A teletrial model will facilitate the recruitment of patients outside of major metropolitan areas. The study is a pragmatic, multicenter, randomised, placebo-controlled, two-arm trial of escalating doses of an oral 1:20 THC/CBD medicinal cannabinoid preparation (10 mg THC:200 mg CBD/mL). It will compare the efficacy and safety outcomes of a titrated dose range of 2.5 mg THC/50mgCBD to 30 mg THC/600 mg CBD per day against a placebo. There is a 2-week patient-determined titration phase, to reach a dose that achieves symptom relief or intolerable side effects, with a further 2 weeks of assessment on the final dose. The primary objective is to assess the effect of escalating doses of a 1:20 THC/CBD medicinal cannabinoid preparation against placebo on change in total symptom distress score, with secondary objectives including establishing a patient-determined effective dose, the effect on sleep quality and overall quality of life. Some patients will be enrolled in a sub-study which will more rigorously evaluate the effect on sleep. DISCUSSION: MedCan-3 is a high-quality, adequately powered, placebo-controlled trial which will help demonstrate the utility of a THC:CBD 1:20 oral medicinal cannabis product in reducing total symptom distress in this population. Secondary outcomes may lead to new hypotheses regarding medicinal cannabis' role in particular symptoms or in particular cancers. The sleep sub-study will test the feasibility of using actigraphy and the Insomnia Severity Index (ISI) in this cohort. This will be the first large-scale palliative care randomised clinical trial to utilise the teletrial model in Australia. If successful, this will have significant implications for trial access for rural and remote patients in Australia and internationally. TRIAL REGISTRATION: ANZCTR ACTRN12622000083796 . Protocol number 001/20. Registered on 21 January 2022. Recruitment started on 8 August 2022.

Preliminary Results from a Phase IV Surveillance Study of Medical Cannabis Use in Australian Patients With Advanced Cancer Receiving Palliative Care.

Introduction: Our research group is conducting three large randomized placebo-controlled trials of medicinal cannabis for cancer symptoms. All participants are invited to take part in a posttrial surveillance study. Methods: Participants were given the manufacturers dosing instructions and liberty to titrate to effect. Data were collected on symptoms (Edmonton Symptom Assessment Scale [ESAS] score), perceived benefits, adverse effects, satisfaction with the product, and dose/frequency. Results: Twenty-six percent of eligible participants consented to take part in the surveillance study. Most participants changed their self-titrated dose at least once. Pain, sleep, and mood were the most frequently cited symptoms which improved. Fatigue, nausea, and cognitive impairment were the most frequently mentioned adverse effects. Conclusion: Participants felt confident making changes to their medicinal cannabis dose within the limits suggested by the manufacturer of each product. A number of benefits and adverse effects were ascribed to the product. Benefits were similar to those described in previous studies.

Cannabidiol oil or placebo in advanced cancer-disease progression and survival: a secondary analysis.

OBJECTIVES: Medical cannabinoids have become increasingly popular over the last decade. Preclinical trials suggest cannabinoids, for example, cannabidiol (CBD), may provide an anticancer effect; however, good-quality clinical information supporting this is lacking. We assessed the effect of CBD treatment on disease progression and survival in patients enrolled in a study of CBD versus placebo for symptom management in patients with advanced cancer (MEDCAN-1). METHODS: We reviewed the clinical records of all patients enrolled in the MEDCAN-1 Study (CBD vs placebo) at days 14, 28 and 56 of study follow-up, for evidence of disease progression. The proportion of participants with disease progression by treatment arm at each time point was compared, as was survival between both groups from study entry to the censor date (end of study period) and the effect of treatment arm and disease progression status on survival. RESULTS: Of the 135 patient records assessed, 128 were included in the final analysis. 36% (n=46) had progressive disease documented at day 28, rising to 49.2% (n=63) by day 56. No significant difference in disease progression was noted between the two groups at days 14 (p=0.33), 28 (p=0.67) or 56 (p=0.50). There was no difference in survival between both groups from study entry to censor date (p=0.38). Disease progression at day 14 was highly predictive of mortality (p<0.001). CONCLUSIONS: In this substudy analysis, treatment with CBD oil did not affect disease progression or survival over the course of 56 days in patients with advanced cancer.

The effects of OPRM1 118A>G on methadone response in pain management in advanced cancer at end of life.

Cancer pain is the most feared symptom at end of life. Methadone has advantages over other opioids but is associated with significant variability in clinical response, making dosing challenging in practice. OPRM1 is the most studied pharmacogene associated with the pharmacodynamics of opioids, however reports on the association of the A118G polymorphism on opioid dose requirements are conflicting, with no reports including methadone as the primary intervention. This association study on OPRM1 A118G and response to methadone for pain management, includes a review of this genetic factor's role in inter-patient variability. Fifty-four adult patients with advanced cancer were recruited in a prospective, multi-centre, open label dose individualization study. Patient characteristics were not shown to influence methadone response, and no significant associations were observed for methadone dose or pain score. The findings of our review of association studies for OPRM1 A118G in advanced cancer pain demonstrate the importance of taking ancestry into account. While our sample size was small, our results were consistent with European populations, but in contrast to studies in Chinese patients, where carriers of the A118G polymorphism were associated with higher opioid dose requirements. Pharmacogenetic studies in palliative care are challenging, continued contribution will support future genotype-based drug dosing guidelines.

Exploring potential anti-inflammatory effects of medicinal cannabis.

PURPOSE: Inflammation is thought to play a key role in malignant disease and may play a significant part in the expression of cancer-related symptoms. Cannabidiol (CBD) is a bioactive compound in cannabis and is reported to have significant anti-inflammatory properties. METHOD: Serial C-reactive protein (CRP) levels were measured in all participants recruited to a randomised controlled trial of CBD versus placebo in patients with symptoms related to advanced cancer. A panel of inflammatory cytokines was measured over time in a subset of these patients. RESULTS: There was no difference between the two arms in the trajectory of CRP or cytokine levels from baseline to day 28. CONCLUSION: We were unable to demonstrate an anti-inflammatory effect of CBD in cancer patients. TRIAL REGISTRATION: ANZCTR 26180001220257, registered 20/07/2018.

Drug dependence epidemiology in palliative care medicinal cannabis trials.

OBJECTIVES: Drug dependence is becoming increasingly common and meeting palliative care patients with substance use disorders is inevitable. However, data on substance use in these patients are lacking. This study aims to evaluate the prevalence of drug dependence in palliative care patients with advanced cancer and correlate with symptom distress and opioid use. METHODS: Palliative care patients with advanced cancer interested in participation in a medicinal cannabis trial were required to complete Alcohol, Smoking and Substance Involvement Screening Test (ASSIST), Edmonton Symptom Assessment Scale (ESAS) and record of concomitant medications including baseline opioid use as part of the eligibility screen. RESULTS: Of the 182 participants, 167 (92%) reported lifetime alcohol and 132/182 (73%) lifetime tobacco use. No participant reached the threshold criteria for high risk of drug dependence with majority being low risk. There was no correlation between ASSIST score, ESAS and oral morphine equivalent. CONCLUSION: This study identified alcohol and tobacco as the main substances used in this group of patients and that most were of very low risk for drug dependence. This suggests routine drug screening for palliative care patient may not be justified, but the high possibility of questionnaire bias is acknowledged.

Quality of life beyond measure: Advanced cancer patients, wellbeing and medicinal cannabis.

Experiences of advanced cancer are assembled and (re)positioned with reference to illness, symptoms and maintaining 'wellbeing'. Medical cannabis is situated at a borderline in this and the broader social domain: between stigmatised and normalised; recreational and pharmaceutical; between perception, experience, discourse and scientific proof of benefit. Yet, in the hyper-medicalised context of randomised clinical trials (RCTs), cancer, wellbeing and medical cannabis are narrowly assessed using individualistic numerical scores. This article attends to patients' perceptions and experiences at this borderline, presenting novel findings from a sociological sub-study embedded within RCTs focused on the use of medical cannabis for symptom relief in advanced cancer. Through a Deleuzo-Guattarian-informed framework, we highlight the fragmentation and reassembling of bodies and propose body-situated experiences of wellbeing in the realm of advanced cancer. Problematising 'biopsychosocial' approaches that centre an individualised disconnected patient body in understandings of wellbeing, experiences of cancer and potential treatments, our findings foreground relational affect and embodied experience, and the role of desire in understanding what wellbeing is and can be. This also underpins and enables exploration of the affective reassembling ascribed to medical cannabis, with particular focus on how it is positioned within RCTs.

Society for Birth Defects Research and Prevention 2022-2027 strategic plan.

BACKGROUND: The sixth Strategic Planning Session of the Society for Birth Defects Research and Prevention (BDRP) was held on April 24-25, 2022, in Alexandria, VA. METHODS: This effort built upon previous strategic planning sessions, conducted every 5 years. RESULTS: The overall process was designed to identify BDRP's vision, purpose, culture, and potential, as well as to communicate the value that BDRP brings to its members, volunteers, partners, and the greater community. CONCLUSIONS: The BDRP 2022-2027 Strategic Plan provides the BDRP leadership, members, and staff with a clearly articulated framework and direction to support long-term sustainability and growth of the society.

Results from a type two hybrid-effectiveness study to implement a preoperative anemia and iron deficiency screening, evaluation, and management pathway.

BACKGROUND: Implementation of pathways to screen surgical patients for preoperative anemia and iron deficiency remains limited. This study sought to measure the impact of a theoretically informed, bespoke change package on improving the uptake of a Preoperative Anemia and Iron Deficiency Screening, Evaluation, and Management Pathway. STUDY DESIGN AND METHODS: Pre-post interventional study using a type two hybrid-effectiveness design evaluated implementation. Four hundred (400) patient medical record reviews provided the dataset (200 pre- and 200-post implementation). The primary outcome measure was compliance with the pathway. Secondary outcome measures (clinical outcomes) were anemia on day of surgery, exposure to a red blood cell (RBC) transfusion, and hospital length of stay. Validated surveys facilitated data collection of implementation measures. Propensity score-adjusted analyses determined the effect of the intervention on clinical outcomes, and a cost analysis determined the economic impact. RESULTS: For the primary outcome, compliance improved significantly post-implementation (Odds Ratio 10.6 [95% CI 4.4-25.5] p < .000). In secondary outcomes, adjusted analyses point estimates showed clinical outcomes were slightly improved for anemia on day of surgery (Odds Ratio 0.792 [95% CI 0.5-1.3] p = .32), RBC transfusion (Odds Ratio 0.86 [95% CI 0.41-1.78] p = .69) and hospital length of stay (Hazard Ratio 0.96 [95% CI 0.77-1.18] p = .67), although these were not statistically significant. Cost savings of $13,340 per patient were realized. Implementation outcomes were favorable for acceptability, appropriateness, and feasibility. CONCLUSION: The change package significantly improved compliance. The absence of a statistically significant change in clinical outcomes may be because the study was powered to detect an improvement in compliance only. Further prospective studies with larger samples are needed. Cost savings of $13,340 per patient were achieved and the change package was viewed favorably.

Corticosteroids for the management of cancer-related fatigue in adults with advanced cancer.

BACKGROUND: Fatigue is the most commonly reported symptom in people with advanced cancer. Cancer-related fatigue (CRF) is pervasive and debilitating, and can greatly impact quality of life (QoL). CRF has a highly variable clinical presentation, likely due to a complex interaction of multiple factors. Corticosteroids are commonly used to improve CRF, but the benefits are unclear and there are significant adverse effects associated with long-term use. With the increasing survival of people with metastatic cancer, the long-term effects of medications are becoming increasingly relevant. Since the impact of CRF can be immensely debilitating and can negatively affect QoL, its treatment warrants further review. OBJECTIVES: To determine the benefits and harms of corticosteroids compared with placebo or an active comparator in adults with advanced cancer and CRF. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, Science Citation Index (ISI Web of Science), LILACS, and two clinical trial registries from inception to 18 July 2022.  SELECTION CRITERIA: We included randomised controlled trials in adults aged ≥18 years. We included participants with advanced cancer who were suffering from CRF. We included trials that randomised participants to corticosteroids at any dose, by any route, administered for the relief of CRF; compared to placebo or an active comparator, including supportive care or non-pharmacological treatments. DATA COLLECTION AND ANALYSIS: Three review authors independently assessed titles identified by the search strategy; two review authors assessed risk of bias; and two extracted data. We extracted the primary outcome of participant-reported fatigue relief using validated scales and secondary outcomes of adverse events, serious adverse events and QoL. We calculated the risk ratio with 95% confidence intervals (CIs) between groups for dichotomous outcomes. We measured arithmetic mean and standard deviation, and reported the mean difference (MD) with 95% CI between groups for continuous outcomes. We used standardised mean difference (SMD) with 95% CIs when an outcome was measured with different instruments measuring the same construct. We used a random-effects model to meta-analyse the outcome data. We rated the certainty of the evidence using GRADE and created two summary of findings tables.  MAIN RESULTS: We included four studies with 297 enroled participants; data were available for only 239 participants. Three studies compared corticosteroid (equivalent ≤ 8 mg dexamethasone) to placebo. One study compared corticosteroid (dexamethasone 4 mg) to an active comparator (modafinil 100 mg). There were insufficient data to evaluate subgroups, such as dose and duration of treatment. One study had a high risk of performance and detection bias due to lack of blinding, and one study had a high risk of attrition bias. Otherwise, we assessed risks of bias as low or unclear. Comparison 1: corticosteroids compared with placebo Participant-reported fatigue relief The was no clear difference between corticosteroids and placebo (SMD -0.46, 95% CI -1.07 to 0.14; 3 RCTs, 165 participants, very low-certainty evidence) for relief of fatigue at one week of the intervention. We downgraded the certainty of the evidence three times for study limitations due to unclear risk of bias, imprecision, and inconsistency. Adverse events There was no clear difference in the occurrence of adverse events between groups, but the evidence is very uncertain (3 RCTs, 165 participants; very low-certainty evidence). Serious adverse events There was no clear difference in the occurrence of serious adverse events between groups, but the evidence is very uncertain (2 RCTs, 118 participants; very low-certainty evidence). Quality of lIfe One study reported QoL at one week using the Edmonton Symptom Assessment System (ESAS) well-being, and found no clear difference in QoL between groups (MD -0.58, 95% CI -1.93 to 0.77). Another study measured QoL using the Quality of Life Questionnaire for Cancer Patients Treated with Anticancer Drugs (QoL-ACD), and found no clear difference between groups. There was no clear difference between groups for either study, but the evidence is very uncertain (2 RCTs, 118 participants; very low-certainty evidence).  Comparison 2: corticosteroids compared with active comparator (modafinil) Participant-reported fatigue relief There was improvement in fatigue from baseline to two weeks in both groups (modafinil MD 10.15, 95% CI 7.43 to 12.87; dexamethasone MD 9.21, 95% CI 6.73 to 11.69), however no clear difference between the two groups (MD -0.94, 95% CI -4.49 to 2.61; 1 RCT, 73 participants, very low-certainty evidence). We downgraded the certainty of the evidence three times for very serious study limitations and imprecision. Adverse events There was no clear difference in the occurrence of adverse events between groups, but the evidence is very uncertain (1 RCT, 73 participants; very low-certainty evidence).  Serious adverse events There were no serious adverse events reported in either group (1 RCT, 73 participants; very low-certainty evidence).  Quality of lIfe One study measured QoL at two weeks, using the ESAS-well-being. There was marked improvement in QoL from baseline in both groups (modafinil MD -2.43, 95% CI -2.88 to -1.98; dexamethasone MD -2.16, 95% CI -2.68 to -1.64), however no clear difference between the two groups (MD 0.27, 95% CI -0.39 to 0.93; 1 RCT, 73 participants, very low-certainty evidence). AUTHORS' CONCLUSIONS: There is insufficient evidence to support or refute the use of systemic corticosteroids in adults with cancer and CRF. We included four small studies that provided very low-certainty of evidence for the efficacy of corticosteroids in the management of CRF. Further high-quality randomised controlled trials with larger sample sizes are required to determine the effectiveness of corticosteroids in this setting.

Phase IIb Randomized, Placebo-Controlled, Dose-Escalating, Double-Blind Study of Cannabidiol Oil for the Relief of Symptoms in Advanced Cancer (MedCan1-CBD).

PURPOSE: To determine whether cannabidiol (CBD) oil can improve symptom distress in patients with advanced cancer receiving palliative care. METHODS: Participants were adults with advanced cancer and symptom distress (Edmonton Symptom Assessment Scale [ESAS] total score of ≥ 10/90) who received titrated CBD oil 100 mg/mL, 0.5 mL once daily to 2 mL three times a day, or matched placebo for 28 days. The primary outcome was ESAS total symptom distress score (TSDS) at day 14. Response was defined as a decrease in TSDS by ≥ 6 at day 14. Secondary outcomes were ESAS TSDS over time, individual symptom scores, patient-determined effective dose, opioid use, Global Impression of Change, depression, anxiety, quality of life, and adverse events. RESULTS: Of the 144 patients randomly assigned, the planned sample size of 58 participants on CBD and 63 on placebo reached the primary analysis point (day 14). The unadjusted change in TSDS from baseline to day 14 was -6.2 (standard deviation, 14.5) for placebo and -3.0 (standard deviation, 15.2) for CBD with no significant difference between arms (P = .24). Similarly, there was no detected difference in proportion of responders (placebo: 37 of 63 [58.7%], CBD: 26 of 58 [44.8%], P = .13). All components of ESAS improved (fell) over time with no difference between arms. The median dose of participant-selected CBD was 400 mg per day with no correlation with opioid dose. There was no detectable effect of CBD on quality of life, depression, or anxiety. Adverse events did not differ significantly between arms apart from dyspnea that was more common with CBD. Most participants reported feeling better or much better at days 14 (53% CBD and 65% placebo) and 28 (70% CBD and 64% placebo). CONCLUSION: CBD oil did not add value to the reduction in symptom distress provided by specialist palliative care alone.

Medicinal cannabis in palliative medicine: lessons learnt from randomised controlled trials.

OBJECTIVES: To detail important lessons learnt while conducting several large, medicinal cannabis (MC) randomised clinical trials in a palliative cancer population. METHODS: Investigators involved in these trials had several meetings to agree on the major lessons learnt and how the various challenges could be mitigated in the future. RESULTS: The lessons were sorted into separate categories: patient confidentiality, family dynamics, driving, cost, unfounded beliefs, accessing specific MC products, trial funding, telehealth and COVID-19, and miscellaneous issues. CONCLUSION: Using MC as the intervention arm in such trials entails some unique regulatory, logistical and other challenges. This short report presents key lessons learnt in conducting these randomised controlled trials in a palliative care population for the benefit of future investigators planning similar trials in a similar patient population.

'What price do you put on your health?': Medical cannabis, financial toxicity and patient perspectives on medication access in advanced cancer.

INTRODUCTION: Following 2016 legislation permitting limited access to cannabis for research and medicinal purposes, the number of randomized clinical trials (RCTs) investigating the effectiveness of medicinal cannabis (MC) on symptom burden relief in cancer contexts has increased in Australia. This study aimed to understand the perceptions, hopes and concerns of people with advanced cancer regarding the future availability and regulation of MC in Australia. METHODS: This qualitative study draws on semistructured interviews conducted between February 2019 and October 2020 in Brisbane, Australia, as part of an MC RCT substudy. Interviews were undertaken on 48 patients with advanced cancer in palliative care eligible to participate in an MC trial (n = 26 participated in an RCT; n = 2 participated in a pilot study; n = 20 declined). Interviews included a discussion of patients' decision-making regarding trial participation, concerns about MC and perceptions of future availability, including cost. Transcribed interviews were analysed inductively and abductively, informed by constructivist thematic analysis conventions. RESULTS: Overall, participants supported making MC legally accessible as a prescription-only medication. Fear of financial toxicity, however, compromised this pathway. Steep posttrial costs of accessing MC prompted several people to decline trial participation, and others to predict-if found effective-that many would either access MC through alternative pathways or reduce their prescribed dosage to enable affordable access. CONCLUSIONS: These findings suggest that-despite a relatively robust universal healthcare system-Australians are potentially vulnerable to and fearful of financial toxicity. Prevalent in the United States, financial toxicity occurs when disadvantaged cancer patients access necessary but expensive medications with lasting consequences: bankruptcy, ongoing anxiety and cancer worry. Interview transcripts indicate that financial fears-and the systems sustaining them-may pose a threat to RCT completion and to equitable access to legal MC. Such findings support calls for embedding qualitative substudies and community partnerships within RCTs, while also suggesting the importance of subsidisation to overcoming injustices. PATIENT OR PUBLIC CONTRIBUTION: A patient advisory committee informed RCT design. This qualitative substudy foregrounds patients' decision-making, perceptions and experiences.

Association of KCNJ6 rs2070995 and methadone response for pain management in advanced cancer at end-of-life.

Opioids are the therapeutic agents of choice to manage moderate to severe pain in patients with advanced cancer, however the unpredictable inter-individual response to opioid therapy remains a challenge for clinicians. While studies are few, the KCNJ6 gene is a promising target for investigating genetic factors that contribute to pain and analgesia response. This is the first association study on polymorphisms in KCNJ6 and response to methadone for pain management in advanced cancer. Fifty-four adult patients with advanced cancer were recruited across two study sites in a prospective, open label, dose individualisation study. Significant associations have been previously shown for rs2070995 and opioid response in opioid substitution therapy for heroin addiction and studies in chronic pain, with mixed results seen in postoperative pain. In this study, no associations were shown for rs2070995 and methadone dose or pain score, consistent with other studies conducted in patients receiving opioids for pain in advanced cancer. There are many challenges in conducting studies in advanced cancer with significant attrition and small sample sizes, however it is hoped that the results of our study will contribute to the evidence base and allow for continued development of gene-drug dosing guidelines for clinicians.

Using a qualitative sub-study to inform the design and delivery of randomised controlled trials on medicinal cannabis for symptom relief in patients with advanced cancer.

BACKGROUND: Recruitment for randomised controlled trials in palliative care can be challenging; disease progression and terminal illness underpin high rates of attrition. Research into participant decision-making in medicinal cannabis randomised controlled trials (RCTs) is very limited. Nesting qualitative sub-studies within RCTs can identify further challenges to participation, informing revisions to study designs and recruitment practices. This paper reports on findings from a qualitative sub-study supporting RCTs of medicinal cannabis for symptom burden relief in patients with advanced cancer in one Australian city. METHODS: Semi-structured qualitative interviews were conducted with 48 patients with advanced cancer, eligible to participate in a medicinal cannabis RCT (n=28 who consented to participate in an RCT; n=20 who declined). An iterative and abductive approach to thematic analysis and data collection fostered exploration of barriers and enablers to participation. RESULTS: Key enablers included participants' enthusiasm and expectations of medicinal cannabis as beneficial (to themselves and future patients) for symptom management, especially after exhausting currently approved options, and a safer alternative to opioids. Some believed medicinal cannabis to have anti-cancer effects. Barriers to participation were the logistical challenges of participating (especially due to driving restrictions and fatigue), reluctance to interfere with an existing care plan, cost, and concerns about receiving the placebo and the uncertainty of the benefit. Some declined due to concerns about side-effects or a desire to continue accessing cannabis independent of the study. CONCLUSIONS: The findings support revisions to subsequent medicinal cannabis RCT study designs, namely, omitting a requirement that participants attend weekly hospital appointments. These findings highlight the value of embedding qualitative sub-studies into RCTs. While some challenges to RCT recruitment are universal, others are context (population, intervention, location) specific. A barrier to participation found in research conducted elsewhere-stigma-was not identified in the current study. Thus, findings have important implications for those undertaking RCTs in the rapidly developing context of medical cannabis.

Does Cannabidiol Have a Benefit as a Supportive Care Drug in Cancer?

OPINION STATEMENT: Cannabinoids have been purported as having a wide range of therapeutic uses although currently, there is minimal evidence to support these claims. Patients with advanced cancer experience many distressing symptoms, with some turning to medicinal cannabis to help alleviate these. Focus has fallen on cannabidiol (CBD) as a potential treatment for a variety of symptoms in advanced cancer due to the lack of psychoactive side effects and the potential molecular mechanisms of action associated with this cannabinoid. Many cannabinoid products are easily available in the community, and more countries are legalizing or allowing over the counter products. Studies show that CBD is generally well tolerated, but there are many potential drug interactions that have not been well studied. Few studies have specifically looked at the role of CBD in treating cancer symptoms, with most focusing on combination cannabinoid products. There are currently many unknowns associated with CBD, including which symptoms it might be best for, appropriate dosing, and route of administration. This is especially important in advanced cancer where patients often have significant organ dysfunction and frailty that could impact on the pharmacology of CBD. A small pilot study has shown promise for a role of CBD in the psychological symptoms associated with advanced cancer. Further research is currently underway to further clarify the role of CBD in this setting and to understand how best it might help our patients. Currently we advocate that CBD be used in supervised clinical trials, so that efficacy and adverse effects can be closely monitored.

Association of polymorphisms in ARRB2 and clinical response to methadone for pain in advanced cancer.

Background: The prescription of methadone in advanced cancer poses multiple challenges due to the considerable interpatient variation seen in effective dose and toxicity. Previous reports have suggested that ARRB2 influences the response to methadone in opioid substitution therapy. Associations with opioid response for pain management in advanced cancer are conflicting, with no studies including methadone as the primary intervention. Methods: In a prospective, multicenter, open-label dose-individualization study, we investigated whether polymorphisms in ARRB2 were associated with methadone dose requirements and pain severity. Results: Significant associations were found for rs3786047, rs1045280, rs2036657 and pain score. Conclusion: While studies are few and the sample size small, ARRB2 genotyping may assist in individualized management of the most feared symptom in advanced cancer.