The safety and pharmacokinetics of single-agent and combination therapy with megestrol acetate and dronabinol for the treatment of HIV wasting syndrome. The DATRI 004 Study Group. Division of AIDS Treatment Research Initiative

Appetite stimulation with cannabis-based medicine and methods for assessment of glomerular filtration in older patients with medical illness: A study protocol

BACKGROUND AND AIM

Malnutrition in older patients is linked to poor appetite. Cannabis-based medicine may have orexigenic properties in older patients, but this has to our knowledge never been investigated. In older patients, uncertainty applies to the accuracy of estimated glomerular filtration rate (eGFR) based on creatinine, which is crucial for medication prescribing. In older patients with poor appetite, the study aims (1) to assess the efficacy of Sativex® (8.1-mg delta-9-tetrahydrocannabinol [THC] and 7.5-mg cannabidiol [CBD]) to stimulate appetite and (2) to compare the performance of various GFR-estimates and measured-GFR (mGFR) for determining gentamicin clearance utilizing population pharmacokinetic (popPK) modelling methods.

METHODS AND OBJECTIVES

This study is composed of two substudies. Substudy 1 is an investigator-initiated single-center, double-blinded, randomized, placebo-controlled, superiority, cross-over study. Substudy 1 will recruit 17 older patients with poor appetite, who will also be invited to substudy 2. Substudy 2 is a single-dose pharmacokinetics study and will recruit 55 patients. Participants will receive Sativex® and placebo in substudy 1 and gentamicin with simultaneous measurements of GFR in substudy 2. The primary endpoints are as follows: Substudy 1-the difference in energy intake between Sativex® and placebo conditions; substudy 2- the accuracy of different eGFR equations compared to mGFR. The secondary endpoints include safety parameters, changes in the appetite hormones, total ghrelin and GLP-1 and subjective appetite sensations, and the creation of popPK models of THC, CBD, and gentamicin.

Should gastroenterologists prescribe cannabis? The highs, the lows and the unknowns

Cannabis, commonly known as marijuana, is a drug extracted from the Cannabis plant known for its psychotropic and medicinal properties. It has been used for healing purposes during ancient times, although its psychoactive components led to its restricted use in medicine. Nonetheless, cannabis is found to have modulatory effects on the endocannabinoid system exhibiting its medicinal role in the gastrointestinal (GI) system. Emerging animal and human studies demonstrate the influential effects of cannabis on a variety of GI diseases including inflammatory bowel disease, motility disorders and GI malignancies. It also has a regulatory role in GI symptoms including nausea and vomiting, anorexia, weight gain, abdominal pain, among others. However, both its acute and chronic use can lead to undesirable side effects such as dependency and addiction, cognitive impairment and cannabinoid hyperemesis syndrome. We will discuss the role of cannabis in the GI system as well as dosing strategies to help guide gastroenterologists to assess its efficacy and provide patient counseling before prescription of medical marijuana.

Specific cannabinoids revive adaptive immunity by reversing immune evasion mechanisms in metastatic tumours

Emerging cancers are sculpted by neo-Darwinian selection for superior growth and survival but minimal immunogenicity; consequently, metastatic cancers often evolve common genetic and epigenetic signatures to elude immune surveillance. Immune subversion by metastatic tumours can be achieved through several mechanisms; one of the most frequently observed involves the loss of expression or mutation of genes composing the MHC-I antigen presentation machinery (APM) that yields tumours invisible to Cytotoxic T lymphocytes, the key component of the adaptive cellular immune response. Fascinating ethnographic and experimental findings indicate that cannabinoids inhibit the growth and progression of several categories of cancer; however, the mechanisms underlying these observations remain clouded in uncertainty. Here, we screened a library of cannabinoid compounds and found molecular selectivity amongst specific cannabinoids, where related molecules such as Δ9-tetrahydrocannabinol, cannabidiol, and cannabigerol can reverse the metastatic immune escape phenotype in vitro by inducing MHC-I cell surface expression in a wide variety of metastatic tumours that subsequently sensitizing tumours to T lymphocyte recognition. Remarkably, H3K27Ac ChIPseq analysis established that cannabigerol and gamma interferon induce overlapping epigenetic signatures and key gene pathways in metastatic tumours related to cellular senescence, as well as APM genes involved in revealing metastatic tumours to the adaptive immune response. Overall, the data suggest that specific cannabinoids may have utility in cancer immunotherapy regimens by overcoming immune escape and augmenting cancer immune surveillance in metastatic disease. Finally, the fundamental discovery of the ability of cannabinoids to alter epigenetic programs may help elucidate many of the pleiotropic medicinal effects of cannabinoids on human physiology.

The Effect of Cannabis-Based Medicine in the Treatment of Cachexia: A Systematic Review and Meta-Analysis

Background: Cachexia is a prevalent condition associated with underlying chronic disease. Wasting of skeletal muscle and adipose tissue loss in cachectic patients is associated with higher rates of disability, reduced quality of life (QoL), and worse prognosis. There is a large unmet need to develop strategies to treat cachexia as there are currently no standardized guidelines in the management of cachexia. Activation of endogenous cannabinoid receptors, through exogenous cannabinoids, has demonstrated potential in increasing appetite, reducing catabolism, and has shown anti-inflammatory properties. Since no single pharmacological agent is currently recommended for use in cachexia, the potential of cannabinoids as an appetite stimulant warrants further research and assessment of current evidence. Objective: This review aims to evaluate the evidence for the efficacy of cannabis-based medicinal products, against placebo and other active treatments, in anorexia-cachexia syndrome in improving appetite, weight, and QoL. Methods: A literature search of the Medline, EMBASE, CENTRAL, and the Web of Science Core Collection, for articles published up to February 2020, was conducted. All randomized controlled trials comparing the use of cannabis-based medicine versus placebo/active treatments for patients with cachexia were screened. The quality of evidence in included studies was assessed using the GRADE framework and any risk of bias was judged using the Cochrane risk of bias tool. Results: A total of five studies, encompassing 934 participants, were found to be eligible. The pooled group effect size for change in appetite was -1.79 (95% confidence interval: -3.77 to 0.19) favoring the control group (p=0.08). Additionally, no significant difference for weight change or change in QoL for cannabinoids versus placebo/other treatment was observed. The quality of evidence for all five studies was assessed to be low. Conclusion: There is a lack of high-quality evidence to recommend the use of cannabinoids in the treatment of cachexia. Given the limited available pharmacological options for cachexia and the potential for cannabinoids to increase appetite and alter the immune system, further research is needed before clinical recommendations on the pharmacological management of cachexia can be made.

Undernutrition and HIV Infection in Sub-Saharan Africa: Health Outcomes and Therapeutic Interventions

PURPOSE OF REVIEW

Sub-Saharan Africa (SSA) is disproportionately burdened by the twin epidemics of food insecurity and HIV infection, and protein-calorie undernutrition is common among persons with HIV (PWH) initiating antiretroviral therapy (ART) in the region. In this review, we discuss the intersection of HIV infection and undernutrition, health outcomes among undernourished PWH starting ART, and the demonstrated and potential benefits of therapeutic interventions such as micro/macronutrient supplementation and pharmacological agents.

RECENT FINDINGS

A low body mass index (BMI), used as a general indicator of poor nutrition in most studies, is associated with impaired immune recovery and increased mortality in the early ART period. The increased risk of mortality is multifactorial, and contributors include undernutrition-related immune system dysfunction, increased susceptibility to opportunistic infections, and metabolic and cardiovascular dysregulation. Clinical trials of micro/macronutrient supplementary feeding, appetite stimulants (hormones and anabolic agents), and recombinant adipokines have shown a benefit for weight gain and metabolic health, but there are few data on mortality or immune recovery. A substantial proportion of PWH in SSA are undernourished, and undernutrition contributes to an increased risk of mortality and other adverse health outcomes. To date, there have been few prospective trials of nutritional supplementation and/or pharmacologic therapy among undernourished PWH in SSA, though findings from other settings suggest a potential benefit in this population.

Mini-review: The therapeutic role of cannabinoids in neuroHIV

In the era of combined antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) is considered a chronic disease with an inflammatory component that specifically targets the brain and causes a high prevalence of HIV-1-associated neurocognitive disorders (HAND). The endocannabinoid (eCB) system has attracted interest as a target for treatment of neurodegenerative disorders, due to the potential anti-inflammatory and neuroprotective properties of cannabinoids, including its potential therapeutic use in HIV-1 neuropathogenesis. In this review, we summarize what is currently known about the structural and functional changes of the eCB system under conditions of HAND. This will be followed by summarizing the current clinical and preclinical findings on the effects of cannabis use and cannabinoids in the context of HIV-1 infection, with specifically focusing on viral load, cognition, inflammation, and neuroprotection. Lastly, we present some potential future directions to better understand the involvement of the eCB system and the role that cannabis use and cannabinoids play in neuroHIV.

Oral Administration of Cannabis and Δ-9-tetrahydrocannabinol (THC) Preparations: A Systematic Review

Background and objective: Changes in cannabis legalization regimes in several countries have influenced the diversification of cannabis use. There is an ever-increasing number of cannabis forms available, which are gaining popularity for both recreational and therapeutic use. From a therapeutic perspective, oral cannabis containing Δ-9-tetrahydrocannabinol (THC) and cannabidiol (CBD) is a promising route of administration but there is still little information about its pharmacokinetics (PK) effects in humans. The purpose of this systematic review is to provide a general overview of the available PK data on cannabis and THC after oral administration. Materials and Methods: A search of the published literature was conducted using the PubMed database to collect available articles describing the PK data of THC after oral administration in humans. Results: The literature search yielded 363 results, 26 of which met our inclusion criteria. The PK of oral THC has been studied using capsules (including oil content), tablets, baked goods (brownies and cookies), and oil and tea (decoctions). Capsules and tablets, which mainly correspond to pharmaceutical forms, were found to be the oral formulations most commonly studied. Overall, the results reflect the high variability in the THC absorption of oral formulations, with delayed peak plasma concentrations compared to other routes of administration. Conclusions: Oral THC has a highly variable PK profile that differs between formulations, with seemingly higher variability in baked goods and oil forms. Overall, there is limited information available in this field. Therefore, further investigations are required to unravel the unpredictability of oral THC administration to increase the effectiveness and safety of oral formulations in medicinal use.

Prospects for the Use of Cannabinoids in Oncology and Palliative Care Practice: A Review of the Evidence

There is an increased interest in the use of cannabinoids in the treatment of symptoms in cancer and palliative care patients. Their multimodal action, in spite of limited efficacy, may make them an attractive alternative, particularly in patients with multiple concomitant symptoms of mild and moderate intensity. There is evidence to indicate cannabis in the treatment of pain, spasticity, seizures, sleep disorders, nausea and vomiting, and Tourette syndrome. Although the effectiveness of cannabinoids is limited, it was confirmed in neuropathic pain management and combination with opioids. A relatively favorable adverse effects profile, including no depressive effect on the respiratory system, may make cannabis complement a rather narrow armamentarium that is in the disposition of a palliative care professional.

Weighing the Benefits and Risks of Medical Marijuana Use: A Brief Review

Despite federal prohibition of medical marijuana possession, sale, and use, marijuana use continues to escalate as state legalization persists and expands. The purpose of this discussion is to provide a brief summary of the evidence regarding both potential benefits and risks of medical marijuana use.

The pitfalls of per se thresholds in accurately identifying acute cannabis intoxication at autopsy

Some laws in the United States define cannabis-impaired driving criteria using various per se language that uses specific concentrations of various cannabinoid compounds to establish driving-under-the-influence (DUI). We hypothesize that there will be decedents whose postmortem toxicology profiles would be considered indicative of an acute cannabinoid intoxication under varying DUI per se laws, despite having survived longer than the expected duration of cannabinoid impairment effects. This study examined decedents in whom quantified cannabis metabolites were detected in Connecticut medical examiner autopsy samples, in which the medically-confined survival interval was longer (4-12 and > 12 h) than the expected duration of cannabinoid impairment effects. Several of the 15 decedents, despite being intubated and/or comatose during the medically-confined period of abstinence, would have exceeded DUI per se limits based upon their toxicology results. The use of drug concentrations alone to equate to an acute cannabis intoxication may result in inappropriate arrest, prosecution, and civil liability.

Megestrol acetate for cachexia-anorexia syndrome. A systematic review

In 1993, megestrol acetate (MA) was approved by the US Food and Drug Administration for the treatment of anorexia, cachexia, or unexplained weight loss in patients with acquired immunodeficiency syndrome. The mechanism by which MA increases appetite is unknown, and its effectiveness for anorexia and cachexia in neoplastic, elderly, and acquired immunodeficiency syndrome patients is under investigation. This is an updated version of a Cochrane systematic review first published in 2005 and later updated in 2013 entitled 'Megestrol acetate for the treatment of anorexia-cachexia syndrome'. MA vs. placebo: in studies where MA was compared with placebo, the overall results showed that MA patients gained weight (mean difference, MD 2.25 kg, 95% CI [1.19, 3.3]) but did not gain quality of life (QOL) (standarized mean difference, SMD 0.5, 95% CI [-0.13, 1.13]), with more adverse events (relative risk, RR 1.46, 95% CI [1.05, 2.04]), but no difference in deaths (RR 1.26, 95% CI [0.70, 2.27]). MA vs. no treatment: MA patients gained weight (MD 1.45 kg, 95% CI [0.15, 2.75]) but did not gain QOL (standardized mean difference 3.89 95% CI [-14, 6.28]). There was no increase in adverse events (RR 0.90, 95% CI [0.39, 2.08]) or deaths (RR 1.01, 95% CI [0.42, 2.45]). MA vs. active drugs: MA patients gained weight (MD 2.5 kg, 95% CI [0.37, 4.64]) but did not gain QOL (MD 0.20 95% CI [-0.02, 0.43]) and did not report an increase in adverse events (RR 1.05 95% CI [0.95, 1.16]) or in deaths (RR 1.53, 95% CI [1.02, 2.29]) Different doses of MA: in studies where lower doses of MA were compared with higher doses of MA, we did not find differences either in weight gain (MD -0.94 kg, 95% CI [-3.33, 1.45]), QOL (MD 0.31 95% CI [-0.19, 0.81]), or adverse events (RR 1.34, 95% CI [0.65, 2.76]). Thus, we cannot reach a conclusion for an optimal dose of MA.

Systematic review and meta-analysis of cannabinoids in palliative medicine

We provide a systematic review and meta-analysis on the efficacy, tolerability, and safety of cannabinoids in palliative medicine. The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PsycINFO, PubMed, Scopus, and http://clinicaltrials.gov, and a selection of cancer journals were searched up until 15th of March 2017. Of the 108 screened studies, nine studies with a total of 1561 participants were included. Overall, the nine studies were at moderate risk of bias. The quality of evidence comparing cannabinoids with placebo was rated according to Grading of Recommendations Assessment, Development, and Evaluation as low or very low because of indirectness, imprecision, and potential reporting bias. In cancer patients, there were no significant differences between cannabinoids and placebo for improving caloric intake (standardized mean differences [SMD]: 0.2 95% confidence interval [CI]: [-0.66, 1.06] P = 0.65), appetite (SMD: 0.81 95% CI: [-1.14, 2.75]; P = 0.42), nausea/vomiting (SMD: 0.21 [-0.10, 0.52] P = 0.19), >30% decrease in pain (risk differences [RD]: 0.07 95% CI: [-0.01, 0.16]; P = 0.07), or sleep problems (SMD: -0.09 95% CI: [-0.62, 0.43] P = 0.72). In human immunodeficiency virus (HIV) patients, cannabinoids were superior to placebo for weight gain (SMD: 0.57 [0.22; 0.92]; P = 0.001) and appetite (SMD: 0.57 [0.11; 1.03]; P = 0.02) but not for nausea/vomiting (SMD: 0.20 [-0.15, 0.54]; P = 0.26). Regarding side effects in cancer patients, there were no differences between cannabinoids and placebo in symptoms of dizziness (RD: 0.03 [-0.02; 0.08]; P = 0.23) or poor mental health (RD: -0.01 [-0.04; 0.03]; P = 0.69), whereas in HIV patients, there was a significant increase in mental health symptoms (RD: 0.05 [0.00; 0.11]; P = 0.05). Tolerability (measured by the number of withdrawals because of adverse events) did not differ significantly in cancer (RD: 1.15 [0.80; 1.66]; P = 0.46) and HIV patients (RD: 1.87 [0.60; 5.84]; P = 0.28). Safety did not differ in cancer (RD: 1.12 [0.86; 1.46]; P = 0.39) or HIV patients (4.51 [0.54; 37.45]; P = 0.32) although there was large uncertainty about the latter reflected in the width of the CI. In one moderate quality study of 469 cancer patients with cancer-associated anorexia, megestrol was superior to cannabinoids in improving appetite, producing >10% weight gain and tolerability. In another study comparing megestrol to dronabinol in HIV patients, megestrol treatment led to higher weight gain without any differences in tolerability and safety. We found no convincing, unbiased, high quality evidence suggesting that cannabinoids are of value for anorexia or cachexia in cancer or HIV patients.

Are cannabinoids effective for HIV wasting syndrome?

INTRODUCTION

Wasting syndrome is a common problem in HIV. It leads to substantive morbidity and mortality. The use of cannabinoids has been suggested as a treatment for weight, but it is not clear whether they are really safe and effective.

METHODS

To answer this question we used Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies and generated a summary of findings table using the GRADE approach.

RESULTS AND CONCLUSIONS

We identified eight systematic reviews including ten studies overall, of which six were randomized trials. We concluded it is not clear whether cannabinoids increase appetite or weight in HIV wasting syndrome because the certainty of the evidence is very low, and they probably lead to frequent adverse effects.

Determination of cannabinoids in hemp nut products in Taiwan by HPLC-MS/MS coupled with chemometric analysis: quality evaluation and a pilot human study

Hemp nuts are mature cannabis seeds obtained after shelling and that are commonly used in traditional Chinese medicine for treating functional constipation. In this work, we screened hemp nut products, classified them, and verified the legality of consuming them. A total of 18 products were purchased from Taiwan, China, and Canada. Validated high-performance liquid chromatography with tandem mass spectrometry methods were developed for analyzing the cannabinoid (i.e., Δ⁹ -tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol) content of the products and the concentration of urinary 11-nor-9-carboxy-THC. Chemometric techniques, namely hierarchical clustering analysis (HCA) and principal component analysis (PCA), were applied for rapidly classifying 11 concentrated powder products in Taiwan. A pilot human study comprising single and multiple administrations of a product with 1.5 µg/g of THC was conducted to examine the urinary 11-nor-9-carboxy-THC concentration. Through optimization of 3² full factorial design, using 60% isopropanol as the extraction solvent exhibited the highest yield of cannabinoids and was applied as the optimal condition in further analysis. The results of HCA and PCA on quality evaluation were in good agreement; however, the tested products possessed distinct CBD-to-THC ratios which ranged widely from 0.1:1 to 46.8:1. Particularly, the products with CBD-to-THC ratios higher than 1:1 were the majority in Taiwan. Our data suggested that all the tested hemp nut products met the Taiwan restriction criterion of 10 µg/g of THC. We propose a usual consumption amount of hemp nut products in Taiwan would unlikely to violate the cut-off point of 15 ng/mL of urinary 11-nor-9-carboxy-THC. Copyright © 2016 John Wiley & Sons, Ltd.

Clinical utility of dronabinol in the treatment of weight loss associated with HIV and AIDS

Since the beginning of the HIV/AIDS epidemic, weight loss has been a common complaint for patients. The use of various definitions defining HIV wasting syndrome has made it difficult to determine its actual prevalence. Despite the use of highly active antiretroviral therapy, it is estimated that the prevalence of HIV wasting syndrome is between 14% and 38%. HIV wasting syndrome may stem from conditions affecting chewing, swallowing, or gastrointestinal motility, neurologic disease affecting food intake or the perception of hunger or ability to eat, psychiatric illness, food insecurity generated from psychosocial or economic concerns, or anorexia due to medications, malabsorption, infections, or tumors. Treatment of HIV wasting syndrome may be managed with appetite stimulants (megestrol acetate or dronabinol), anabolic agents (testosterone, testosterone analogs, or recombinant human growth hormone), or, rarely, cytokine production modulators (thalidomide). The goal of this review is to provide an in-depth evaluation based on existing clinical trials on the clinical utility of dronabinol in the treatment of weight loss associated with HIV/AIDS. Although total body weight gain varies with dronabinol use (–2.0 to 3.2 kg), dronabinol is a well-tolerated option to promote appetite stimulation. Further studies are needed with standardized definitions of HIV-associated weight loss and clinical outcomes, robust sample sizes, safety and efficacy data on chronic use of dronabinol beyond 52 weeks, and associated virologic and immunologic outcomes.

Comprehensive Review of Medicinal Marijuana, Cannabinoids, and Therapeutic Implications in Medicine and Headache: What a Long Strange Trip It's Been …

BACKGROUND

The use of cannabis, or marijuana, for medicinal purposes is deeply rooted though history, dating back to ancient times. It once held a prominent position in the history of medicine, recommended by many eminent physicians for numerous diseases, particularly headache and migraine. Through the decades, this plant has taken a fascinating journey from a legal and frequently prescribed status to illegal, driven by political and social factors rather than by science. However, with an abundance of growing support for its multitude of medicinal uses, the misguided stigma of cannabis is fading, and there has been a dramatic push for legalizing medicinal cannabis and research. Almost half of the United States has now legalized medicinal cannabis, several states have legalized recreational use, and others have legalized cannabidiol-only use, which is one of many therapeutic cannabinoids extracted from cannabis. Physicians need to be educated on the history, pharmacology, clinical indications, and proper clinical use of cannabis, as patients will inevitably inquire about it for many diseases, including chronic pain and headache disorders for which there is some intriguing supportive evidence.

OBJECTIVE

To review the history of medicinal cannabis use, discuss the pharmacology and physiology of the endocannabinoid system and cannabis-derived cannabinoids, perform a comprehensive literature review of the clinical uses of medicinal cannabis and cannabinoids with a focus on migraine and other headache disorders, and outline general clinical practice guidelines.

CONCLUSION

The literature suggests that the medicinal use of cannabis may have a therapeutic role for a multitude of diseases, particularly chronic pain disorders including headache. Supporting literature suggests a role for medicinal cannabis and cannabinoids in several types of headache disorders including migraine and cluster headache, although it is primarily limited to case based, anecdotal, or laboratory-based scientific research. Cannabis contains an extensive number of pharmacological and biochemical compounds, of which only a minority are understood, so many potential therapeutic uses likely remain undiscovered. Cannabinoids appear to modulate and interact at many pathways inherent to migraine, triptan mechanisms ofaction, and opiate pathways, suggesting potential synergistic or similar benefits. Modulation of the endocannabinoid system through agonism or antagonism of its receptors, targeting its metabolic pathways, or combining cannabinoids with other analgesics for synergistic effects, may provide the foundation for many new classes of medications. Despite the limited evidence and research suggesting a role for cannabis and cannabinoids in some headache disorders, randomized clinical trials are lacking and necessary for confirmation and further evaluation.

Medical marijuana for cancer

Answer questions and earn CME/CNE Marijuana has been used for centuries, and interest in its medicinal properties has been increasing in recent years. Investigations into these medicinal properties has led to the development of cannabinoid pharmaceuticals such as dronabinol, nabilone, and nabiximols. Dronabinol is best studied in the treatment of nausea secondary to cancer chemotherapy and anorexia associated with weight loss in patients with acquired immune deficiency syndrome, and is approved by the US Food and Drug Administration for those indications. Nabilone has been best studied for the treatment of nausea secondary to cancer chemotherapy. There are also limited studies of these drugs for other conditions. Nabiximols is only available in the United States through clinical trials, but is used in Canada and the United Kingdom for the treatment of spasticity secondary to multiple sclerosis and pain. Studies of marijuana have concentrated on nausea, appetite, and pain. This article will review the literature regarding the medical use of marijuana and these cannabinoid pharmaceuticals (with emphasis on indications relevant to oncology), as well as available information regarding adverse effects of marijuana use.

Dronabinol and chronic pain: importance of mechanistic considerations

INTRODUCTION

Although medicinal cannabis has been used for many centuries, the therapeutic potential of delta-9-tetrahydrocannabinol (Δ9-THC; international non-proprietary name = dronabinol) in current pain management remains unclear. Several pharmaceutical products with defined natural or synthesized Δ9-THC content have been developed, resulting in increasing numbers of clinical trials investigating the analgesic efficacy of dronabinol in various pain conditions. Different underlying pain mechanisms, including sensitization of nociceptive sensory pathways and alterations in cognitive and autonomic processing, might explain the varying analgesic effects of dronabinol in chronic pain states.

AREAS COVERED

The pharmacokinetics, pharmacodynamics and mechanisms of action of products with a defined dronabinol content are summarized. Additionally, randomized clinical trials investigating the analgesic efficacy of pharmaceutical cannabis based products are reviewed for the treatment of chronic nonmalignant pain.

EXPERT OPINION

We suggest a mechanism-based approach beyond measurement of subjective pain relief to evaluate the therapeutic potential of dronabinol in chronic pain management. Development of objective mechanistic diagnostic biomarkers reflecting altered sensory and cognitive processing in the brain is essential to evaluate dronabinol induced analgesia, and to permit identification of responders and/or non-responders to dronabinol treatment.

Pharmacologic management of human immunodeficiency virus wasting syndrome

Pharmacologic interventions for human immunodeficiency virus (HIV) wasting have been studied since the 1990s, but the results of these interventions have been difficult to compare because the studies used different HIV wasting definitions and assessed various patient outcomes. Thus, we performed a systematic review of the current literature to identify studies that evaluated pharmacologic management of HIV wasting and to compare and contrast treatment options. Further, we provide a comprehensive review of these treatment options and describe the definition of HIV wasting used in each study, the outcomes assessed, and whether antiretroviral therapy was used during the HIV wasting treatment. Literature searches of the PubMed/Medline (1946-2014) and Google Scholar databases were performed, and a review of the bibliographies of retrieved articles was performed to identify additional references. Only English-language articles pertaining to humans and HIV-infected individuals were evaluated. Thirty-six studies were identified that assessed pharmacologic interventions to treat HIV wasting. Appetite stimulants, such as megestrol acetate, have been shown to increase total body weight (TBW) and body mass index in HIV-infected patients with wasting. Studies evaluating dronabinol showed conflicting data on TBW increases, but the drug may have minimal benefit on body composition compared with other appetite stimulants. Testosterone has been shown to be effective in HIV wasting for those who suffer from hypogonadism. Recombinant human growth hormone has been evaluated for HIV wasting and has shown promising results for TBW and lean body mass increases. Thalidomide has been studied; however, its use is limited due to its toxicities. Although megestrol acetate and dronabinol are approved by the U.S. Food and Drug Administration (FDA) for the treatment of HIV wasting, it is important to recognize other comorbidities such as depression or hypogonadism that may contribute to the patient's appetite and weight loss. If a patient is diagnosed with hypogonadism and HIV wasting, testosterone would be a good therapeutic option. Although mirtazapine is not FDA approved for the management of HIV wasting, it has been shown to promote weight gain while treating depression symptoms. Mirtazapine may be a promising pharmacologic option in the management of HIV wasting and depression, but further research is needed.

Patterns and correlates of cannabis use among individuals with HIV/AIDS in Maritime Canada

BACKGROUND

The prevalence of cannabis use in HIV-infected individuals is high and its long-term effects are unclear.

METHODS

The prevalence, perceived benefits and consequences, and predictors of cannabis use were studied using a cross-sectional survey in two immunodeficiency clinics in Maritime Canada.

RESULTS

Current cannabis use was identified in 38.5% (87 of 226) of participants. Almost all cannabis users (85 of 87 [97.7%]) acknowledged its use for recreational purposes, with 21.8% (19 of 87) reporting medicinal cannabis use. The majority of patients enrolled in the present study reported mild or no symptoms related to HIV (n=179). Overall, 80.5% (70 of 87) of the cannabis-using participants reported a symptom-relieving benefit, mostly for relief of stress, anorexia or pain. Participants consumed a mean (± SD) of 18.3±21.1 g of cannabis per month and spent an average of $105.15±109.87 on cannabis per month. Cannabis use was associated with rural residence, lower income level, driving under the influence of a substance, and consumption of ecstasy and tobacco. Income level, ecstasy use and tobacco use were retained as significant predictors in regression modelling. Cannabis use was not associated with adverse psychological outcomes.

DISCUSSION

Prolonged previous cannabis consumption and the substantial overlap between recreational and medicinal cannabis use highlight the challenges in obtaining a tenable definition of medicinal cannabis therapy.

LC-MS/MS method for determination of megestrol in human plasma and its application in bioequivalence study

A rapid and highly selective liquid chromatography-tandem mass spectrometric (LC-MS/MS) method for the determination of megestrol in human plasma was described using medrysone as internal standard (IS). Blood samples were collected from 20 healthy volunteers after oral administration of 160 mg megestrol acetate dispersible tablets. The analytes were extracted by liquid-liquid extraction procedure and separated on a hanbon lichrospher column with the mobile phase of methanol and water containing 0.1% formic acid and 20 mmol/L ammonium acetate (5:1, v/v). Positive ion electrospray ionization with multiple reaction-monitoring mode (MRM) was employed by monitoring the transitions m/z 385.5-325.4 and m/z 387.5-327.4 for megestrol and medrysone, respectively. Under the isocratic separation conditions, the chromatographic run time was approximately 2.54 min for megestrol and 2.59 min for medrysone. The calibration curve range was from 0.5 to 200.0 ng/mL. The inter-batch and intra-batch precision and accuracy were less than 5.2% relative standard deviation (RSD) and 6.4% relative error (RE). The proposed method was successfully applied in the bioequivalence study of megestrol acetate dispersible tablets.

Safety of megestrol acetate in palliating anorexia-cachexia syndrome in patients with castration-resistant prostate cancer

There are concerns whether megestrol acetate (MA) stimulates the growth of prostate cancer in castration-resistant prostate cancer (CRPC). We evaluated the effect of cumulative doses of MA on the disease-specific survival (DSS) in patients with CRPC who were receiving Docetaxel-based chemotherapy. From July 2003 through June 2009, we identified 109 consecutive patients with CRPC and who had received docetaxel-based chemotherapy. Of these patients, 68 (62.4%) have not received MA, whereas 21 patients (19.3%) and 20 patients (18.3%) had received low dose MA (total ≤ 18,400 mg) and high dose MA (total > 18,400 mg), respectively. We assessed the effect of several variables on DSS. None of the clinicopathological variables differed among the three groups. When comparing DSS using Kaplan-Meier analysis, there was no statistically significant survival differences among the three groups (P = 0.546). Using multivariate Cox proportional analyses with backward elimination, the number of docetaxel cycles was only significant factor predicting DSS (HR: 0.578, 95% CI: 0.318-0.923, P = 0.016). Cumulative doses of MA as adjuvant treatment for patients with CRPC and who are receiving docetaxel-based chemotherapy, did not affect their DSS. Therefore, MA can be safely administered in cachexic patients with CRPC.

The medical use of cannabis for reducing morbidity and mortality in patients with HIV/AIDS

BACKGROUND

The use of cannabis (marijuana) or of its psychoactive ingredient delta-9-tetrahydrocannabinol (THC) as a medicine has been highly contested in many settings.There have been claims that smoked or ingested cannabis, either in its natural form or artificial form (pharmaceutically manufactured drug such as dronabinol), improves the appetites of people with AIDS, results in weight gain and lifts mood, thus improving the quality of life.

OBJECTIVES

The objectives of this review were to assess whether cannabis (in its natural or artificially produced form), either smoked or ingested, decreases the morbidity or mortality of patients infected with HIV.

SEARCH METHODS

The search strategy was conducted to July 2012 and was based on that of the Cochrane HIV/AIDS Review Group. We searched the following databases: CENTRAL/CCTR, MEDLINE and EMBASE. In addition, searching was performed where necessary of journals, reference lists of articles, and conference proceedings.

SELECTION CRITERIA

The review included randomised controlled trials (RCTs) of any cannabis intervention, in any form, and administered by any route, in adults with HIV or AIDS, compared with placebo or with a known effective treatment, and conducted in a hospital, outpatient clinic, or home care setting. Quasi-randomised studies using any form of cannabis as an intervention in patients with HIV or AIDS were also included.

DATA COLLECTION AND ANALYSIS

Data from the eligible studies were extracted and coded independently by two researchers, using a standardised data extraction form. Data were then analysed using RevMan 5.0. No meta-analyses were performed.

MAIN RESULTS

A total of seven relevant studies were included in the review, reported in eight publications. All were randomised controlled studies, with four utilising a parallel group design, two a within-subject randomisation and two a cross-over design. All of the studies were of a fairly short duration, ranging from 21 days to 84 days. In only four papers (in effect, three studies) were sequence generation and allocation concealment judged to be adequate. The use of cannabis and rapidly acting cannabinoids posed considerable challenges for blinding, as the psychoactive effects are expected to be quickly discernible to study participants, particularly those who have been previous users of such products. Dronabinol was expected to be more easily blinded. The outcomes measured were variable, including change in weight, change in body fat (measured as a percentage of total body weight), change in appetite (measured on a visual analogue scale), change in caloric intake (measured in kcals/kg/24hr), change in nausea and vomiting (measured on a visual analogue scale), change in performance (measured by Karnofsky performance score or specific tests for memory and dexterity) and change in mood (measured on a visual analogue scale).The evidence for substantial effects on morbidity and mortality is currently limited. Data from only one relatively small study (n=139, of which only 88 were evaluable), conducted in the period before access to highly-active antiretroviral therapy (HAART), showed that patients administered dronabinol were twice as likely to gain 2kg or more in body weight (RR 2.09), but the confidence interval for this measure (95% CI 0.72 - 6.06) included unity. The mean weight gain in the dronabinol group was only 0.1kg, compared with a loss of 0.4kg in the placebo group. However, the quality of sequence generation and allocation concealment in this study, in which participants were randomised by centre, could not be assessed.

AUTHORS' CONCLUSIONS

Despite dronabinol being registered by at least some medicines regulatory authorities for the treatment of AIDS-associated anorexia, and some jurisdictions making allowances for the "medical" use of marijuana by patients with HIV/AIDS, evidence for the efficacy and safety of cannabis and cannabinoids in this setting is lacking. Such studies as have been performed have been of short duration, in small numbers of patients, and have focused on short-term measures of efficacy. Long-term data, showing a sustained effect on AIDS-related morbidity and mortality and safety in patients on effective antiretroviral therapy, has yet to be presented. Whether the available evidence is sufficient to justify a wide-ranging revisiting of medicines regulatory practice remains unclear.

Megestrol acetate for treatment of anorexia-cachexia syndrome

BACKGROUND

This is an updated version of a previously published review in The Cochrane Library (2005, Issue 2) on 'Megestrol acetate for the treatment of anorexia-cachexia syndrome'. Megestrol acetate (MA) is currently used to improve appetite and to increase weight in cancer-associated anorexia. In 1993, MA was approved by the US Food and Drug Administration for the treatment of anorexia, cachexia or unexplained weight loss in patients with AIDS. The mechanism by which MA increases appetite is unknown and its effectiveness for anorexia and cachexia in neoplastic and AIDS (acquired immunodeficiency syndrome) patients is under investigation.

OBJECTIVES

To evaluate the efficacy, effectiveness and safety of MA in palliating anorexia-cachexia syndrome in patients with cancer, AIDS and other underlying pathologies.

SEARCH METHODS

We sought studies through an extensive search of electronic databases, journals, reference lists, contact with investigators and other search strategies outlined in the methods. The most recent search for this update was carried out in May 2012.

SELECTION CRITERIA

Studies were included in the review if they assessed MA compared to placebo or other drug treatments in randomised controlled trials of patients with a clinical diagnosis of anorexia-cachexia syndrome related to cancer, AIDS or any other underlying pathology.

DATA COLLECTION AND ANALYSIS

Two independent review authors conducted data extraction and evaluated methodological quality. We performed quantitative analyses using appetite and quality of life as a dichotomous variable, and analysed weight gain as continuous and dichotomous variables.

MAIN RESULTS

We included 35 trials in this update, the same number but not the same trials as in the previous version of the review. The trials comprised 3963 patients for effectiveness and 3180 for safety. Sixteen trials compared MA at different doses with placebo, seven trials compared different doses of MA with other drug treatments and 10 trials compared different doses of MA. Meta-analysis showed a benefit of MA compared with placebo, particularly with regard to appetite improvement and weight gain in cancer, AIDS and other underlying conditions, and lack of benefit in the same patients when MA was compared to other drugs. There was insufficient information to define the optimal dose of MA, but higher doses were more related to weight improvement than lower doses. Quality of life improvement in patients was seen only when comparing MA versus placebo but not other drugs in both subcategories: cancer and AIDS. Oedema, thromboembolic phenomena and deaths were more frequent in the patients treated with MA. More than 40 side effects were studied.

AUTHORS' CONCLUSIONS

This review shows that MA improves appetite and is associated with slight weight gain in cancer, AIDS and in patients with other underlying pathology. Despite the fact that these patients are receiving palliative care they should be informed of the risks involved in taking MA.

The therapeutic potential of cannabis and cannabinoids

BACKGROUND

Cannabis-based medications have been a topic of intense study since the endogenous cannabinoid system was discovered two decades ago. In 2011, for the first time, a cannabis extract was approved for clinical use in Germany.

METHODS

Selective literature review.

RESULTS

Cannabis-based medications exert their effects mainly through the activation of cannabinoid receptors (CB1 and CB2). More than 100 controlled clinical trials of cannabinoids or whole-plant preparations for various indications have been conducted since 1975. The findings of these trials have led to the approval of cannabis-based medicines (dronabinol, nabilone, and a cannabis extract [THC:CBD=1:1]) in several countries. In Germany, a cannabis extract was approved in 2011 for the treatment of moderate to severe refractory spasticity in multiple sclerosis. It is commonly used off label for the treatment of anorexia, nausea, and neuropathic pain. Patients can also apply for government permission to buy medicinal cannabis flowers for self-treatment under medical supervision. The most common side effects of cannabinoids are tiredness and dizziness (in more than 10% of patients), psychological effects, and dry mouth. Tolerance to these side effects nearly always develops within a short time. Withdrawal symptoms are hardly ever a problem in the therapeutic setting.

CONCLUSION

There is now clear evidence that cannabinoids are useful for the treatment of various medical conditions.

Immunomodulatory properties of kappa opioids and synthetic cannabinoids in HIV-1 neuropathogenesis

Anti-retroviral therapy (ART) has had a tremendous impact on the clinical outcomes of HIV-1 infected individuals. While ART has produced many tangible benefits, chronic, long-term consequences of HIV infection have grown in importance. HIV-1-associated neurocognitive disorder (HAND) represents a collection of neurological syndromes that have a wide range of functional cognitive impairments. HAND remains a serious threat to AIDS patients, and there currently remains no specific therapy for the neurological manifestations of HIV-1. Based upon work in other models of neuroinflammation, kappa opioid receptors (KOR) and synthetic cannabinoids have emerged as having neuroprotective properties and the ability to dampen pro-inflammatory responses of glial cells; properties that may have a positive influence in HIV-1 neuropathogenesis. The ability of KOR ligands to inhibit HIV-1 production in human microglial cells and CD4 T lymphocytes, demonstrate neuroprotection, and dampen chemokine production in astrocytes provides encouraging data to suggest that KOR ligands may emerge as potential therapeutic agents in HIV neuropathogenesis. Based upon findings that synthetic cannabinoids inhibit HIV-1 expression in human microglia and suppress production of inflammatory mediators such as nitric oxide (NO) in human astrocytes, as well as a substantial literature demonstrating neuroprotective properties of cannabinoids in other systems, synthetic cannabinoids have also emerged as potential therapeutic agents in HIV neuropathogenesis. This review focuses on these two classes of compounds and describes the immunomodulatory and neuroprotective properties attributed to each in the context of HIV neuropathogenesis.

Pharmacokinetics of a combination of Δ9-tetrahydro-cannabinol and celecoxib in a porcine model of hemorrhagic shock

Hemorrhagic shock involves loss of a substantial portion of circulating blood volume leading to diminished cardiac output and oxygen delivery to peripheral tissues. In situations where an immediate resuscitation cannot be provided, pharmacotherapy with a novel combination of Δ9-tetrahydro-cannabinol (THC) and celecoxib (CEL) is currently investigated as an alternative strategy to prevent organ damage. In the present study, 28 Yorkshire×Landrace pigs were used to study the pharmacokinetics of THC and CEL in an established porcine model of hemorrhagic shock. Pigs in hemorrhagic shock received 0.5, 1 or 4 mg/kg THC and 2 mg/kg CEL, while normotensive pigs received 1 mg/kg THC and 2 mg/kg CEL by intravenous injection. THC and CEL plasma concentrations were simultaneously determined by LC-MS/MS. Pharmacokinetic parameters and their between animal variability were obtained using standard non-compartmental analysis as well as a compartmental analysis using nonlinear mixed effects modeling. The concentration-time profiles of THC and CEL followed a multi-exponential decline and their pharmacokinetics were similar in hemorrhagic shock and normotensive conditions, despite the substantial change in hemodynamics in the animals with shock. This interesting finding might be due to the pharmacologic effect of the THC/CEL combination, which is intended to maintain adequate perfusion of vital organs in shock. Overall, this study established THC and CEL pharmacokinetics in a porcine shock model and provides the basis for dose selection in further studies of THC and CEL in this indication.

Food effect on the bioavailability of two distinct formulations of megestrol acetate oral suspension

Objective:

Megestrol acetate oral suspension (MAOS) is an appetite stimulant indicated for cachexia in patients with AIDS. It is available in its original formulation, Megace^® (MAOS), and as a nanocrystal dispersion, Megace^® ES (MA-ES). Three studies were conducted to evaluate the pharmacokinetic properties of these formulations under fed and fasting conditions.

Methods:

An open-label, crossover trial was conducted in 24 healthy males randomized to MA-ES 625 mg/5 mL given with a high-calorie, high-fat meal, or after an overnight fast. Blood samples were drawn at multiple time points and pharmacokinetic parameters were determined. Two separate, open-label reference studies evaluated MAOS 800 mg/20 mL in 40 fed or 40 fasting healthy male volunteers.

Results:

In fasting MA-ES subjects, the average maximum concentration (C_max) was 30% less than the fed C_max value. For MAOS, fasting C_max was 86% less than fed C_max. In fasting subjects, the area under the curve was 12,095 ng·h/mL for MA-ES, and 8,942 ng·h/mL for MAOS. In fed subjects, the absorption of the two formulations was comparable.

Conclusion:

Bioavailability and absorption are greater for MA-ES than MAOS in fasting subjects. MA-ES may be a preferred formulation of megestrol acetate when managing cachectic patients whose caloric intake is reduced.

Synthetic and plant-derived cannabinoid receptor antagonists show hypophagic properties in fasted and non-fasted mice

BACKGROUND AND PURPOSE

Obesity is a severe health problem in the modernized world and understanding the central nervous mechanisms underlying food-seeking behaviour and reward are at the forefront of medical research. Cannabinoid receptors have proven an efficient target to suppress hunger and weight gain by their pharmacological inactivation.

EXPERIMENTAL APPROACH

A standard fasted protocol and a novel long-term home-cage observation system with free-feeding animals were used to assess the feeding behaviour of mice treated with the CB1 antagonist AM251. Similarly, the effects of the phytocannabinoid Delta9-tetrahydrocannabivarin (Delta9-THCV), which behaves like a CB1 antagonist, were also determined in free-feeding animals.

KEY RESULTS

AM251 suppressed food intake and weight gain in fasted and non-fasted animals. The suppression of food intake by AM251 (10 mg.kg-1) endured for a period of 6-8 h when administered acutely, and was continuous when injected for four consecutive days. Pure Delta9-THCV also induced hypophagia and weight reduction at doses as low as 3 mg.kg-1. No rebound was observed on the following day with all drug groups returning to normal activity and feeding regimes. However, a Delta9-THCV-rich cannabis-extract failed to suppress food intake and weight gain, possibly due to residual Delta9-tetrahydrocannabinol (Delta9-THC) in the extract. This Delta9-THC effect was overcome by the co-administration of cannabidiol.

CONCLUSIONS AND IMPLICATIONS

The data strongly suggest (i) the long-term home-cage observation system is a sensitive and obesity-relevant tool, and (ii) the phytocannabinoid Delta9-THCV is a novel compound with hypophagic properties and a potential treatment for obesity

Adverse effects of medical cannabinoids: a systematic review

BACKGROUND

The therapeutic use of cannabis and cannabis-based medicines raises safety concerns for patients, clinicians, policy-makers, insurers, researchers and regulators. Although the efficacy of cannabinoids is being increasingly demonstrated in randomized controlled trials, most safety information comes from studies of recreational use.

METHODS

We performed a systematic review of safety studies of medical cannabinoids published over the past 40 years to create an evidence base for cannabis-related adverse events and to facilitate future cannabis research initiatives. We critically evaluated the quality of published studies with a view to identifying ways to improve future studies.

RESULTS

A total of 321 articles were eligible for evaluation. After excluding those that focused on recreational cannabis use, we included 31 studies (23 randomized controlled trials and 8 observational studies) of medical cannabis use in our analysis. In the 23 randomized controlled trials, the median duration of cannabinoid exposure was 2 weeks (range 8 hours to 12 months). A total of 4779 adverse events were reported among participants assigned to the intervention. Most (4615 [96.6%]) were not serious. Of the 164 serious adverse events, the most common was relapse of multiple sclerosis (21 events [12.8%]), vomiting (16 events [9.8%]) and urinary tract infection (15 events [9.1%]). The rate of nonserious adverse events was higher among participants assigned to medical cannabinoids than among controls (rate ratio [RR] 1.86, 95% confidence interval [CI] 1.57-2.21); the rates of serious adverse events did not differ significantly between these 2 groups (RR 1.04, 95% CI 0.78-1.39). Dizziness was the most commonly reported nonserious adverse event (714 events [15.5%]) among people exposed to cannabinoids.

INTERPRETATION

Short-term use of existing medical cannabinoids appeared to increase the risk of nonserious adverse events. The risks associated with long-term use were poorly characterized in published clinical trials and observational studies. High-quality trials of long-term exposure are required to further characterize safety issues related to the use of medical cannabinoids.

Cannabinoids in health and disease

Cannabis sativa L. preparations have been used in medicine for millenia. However, concern over the dangers of abuse led to the banning of the medicinal use of marijuana in most countries in the 1930s. Only recently, marijuana and individual natural and synthetic cannabinoid receptor agonists and antagonists, as well as chemically related compounds, whose mechanism of action is still obscure, have come back to being considered of therapeutic value. However, their use is highly restricted. Despite the mild addiction to cannabis and the possible enhancement of addiction to other substances of abuse, when combined with cannabis, the therapeutic value of cannabinoids is too high to be put aside. Numerous diseases, such as anorexia, emesis, pain, inflammation, multiple sclerosis, neurodegenerative disorders (Parkinson's disease, Huntington's disease, Tourette's syndrome, Alzheimer's disease), epilepsy, glaucoma, osteoporosis, schizophrenia, cardiovascular disorders, cancer, obesity, and metabolic syndrome-related disorders, to name just a few, are being treated or have the potential to be treated by cannabinoid agonists/antagonists/cannabinoid-related compounds. In view of the very low toxicity and the generally benign side effects of this group of compounds, neglecting or denying their clinical potential is unacceptable--instead, we need to work on the development of more selective cannabinoid receptor agonists/antagonists and related compounds, as well as on novel drugs of this family with better selectivity, distribution patterns, and pharmacokinetics, and--in cases where it is impossible to separate the desired clinical action and the psychoactivity--just to monitor these side effects carefully.

Dronabinol and Marijuana in HIV-Positive Marijuana Smokers

OBJECTIVES

Individuals with HIV constitute the largest group using cannabinoids for medicinal reasons; yet, no studies have directly compared the tolerability and efficacy of smoked marijuana and oral dronabinol maintenance in HIV-positive marijuana smokers. This placebo-controlled within-subjects study evaluated marijuana and dronabinol across a range of behaviors: eating topography, mood, cognitive performance, physiologic measures, and sleep.

METHODS

HIV-positive marijuana smokers (n = 10) completed 2 16-day inpatient phases. Each dronabinol (5 and 10 mg) and marijuana (2.0% and 3.9% Delta9-tetrahydrocannabinol [THC]) dose was administered 4 times daily for 4 days, but only 1 drug was active per day, thereby maintaining double-blind dosing. Four days of placebo washout separated each active cannabinoid condition.

RESULTS

As compared with placebo, marijuana and dronabinol dose dependently increased daily caloric intake and body weight in HIV-positive marijuana smokers. All cannabinoid conditions produced significant intoxication, except for low-dose dronabinol (5 mg); the intoxication was rated positively (eg, "good drug effect") with little evidence of discomfort and no impairment of cognitive performance. Effects of marijuana and dronabinol were comparable, except that only marijuana (3.9% THC) improved ratings of sleep.

CONCLUSIONS

These data suggest that for HIV-positive marijuana smokers, both dronabinol (at doses 8 times current recommendations) and marijuana were well tolerated and produced substantial and comparable increases in food intake.

The endocannabinoid system as an emerging target of pharmacotherapy

The recent identification of cannabinoid receptors and their endogenous lipid ligands has triggered an exponential growth of studies exploring the endocannabinoid system and its regulatory functions in health and disease. Such studies have been greatly facilitated by the introduction of selective cannabinoid receptor antagonists and inhibitors of endocannabinoid metabolism and transport, as well as mice deficient in cannabinoid receptors or the endocannabinoid-degrading enzyme fatty acid amidohydrolase. In the past decade, the endocannabinoid system has been implicated in a growing number of physiological functions, both in the central and peripheral nervous systems and in peripheral organs. More importantly, modulating the activity of the endocannabinoid system turned out to hold therapeutic promise in a wide range of disparate diseases and pathological conditions, ranging from mood and anxiety disorders, movement disorders such as Parkinson's and Huntington's disease, neuropathic pain, multiple sclerosis and spinal cord injury, to cancer, atherosclerosis, myocardial infarction, stroke, hypertension, glaucoma, obesity/metabolic syndrome, and osteoporosis, to name just a few. An impediment to the development of cannabinoid medications has been the socially unacceptable psychoactive properties of plant-derived or synthetic agonists, mediated by CB(1) receptors. However, this problem does not arise when the therapeutic aim is achieved by treatment with a CB(1) receptor antagonist, such as in obesity, and may also be absent when the action of endocannabinoids is enhanced indirectly through blocking their metabolism or transport. The use of selective CB(2) receptor agonists, which lack psychoactive properties, could represent another promising avenue for certain conditions. The abuse potential of plant-derived cannabinoids may also be limited through the use of preparations with controlled composition and the careful selection of dose and route of administration. The growing number of preclinical studies and clinical trials with compounds that modulate the endocannabinoid system will probably result in novel therapeutic approaches in a number of diseases for which current treatments do not fully address the patients' need. Here, we provide a comprehensive overview on the current state of knowledge of the endocannabinoid system as a target of pharmacotherapy.

Cell-cell communication by endocannabinoids during immune surveillance of the central nervous system

The immune system is designed to defend the organism from hazardous infection. The way by which cells of the immune system perform this function can be dangerous for the survival and function of the neuronal network in the brain. An attack of immune cells inside the brain includes the potential for severe neuronal damage or cell death and therefore impairment of CNS function. To avoid such undesirable action of the immune system, the CNS harbours an impressive arsenal of cellular and molecular mechanisms enabling strict control of immune reactions--the so-called "immune privilege". Under inflammatory and pathological conditions, loss of control of the CNS immune system results in the activation of neuronal damage cascades frequently associated with neurological disease. On the other hand, processes of neuroprotection and neurorepair after neuronal damage depend on a steady and tightly controlled immune surveillance. Accordingly, the immune system serves a highly specialized function in the CNS including negative feedback mechanisms that control immune reactions. Recent studies have revealed that endocannabinoids participate in one of the most important ones of the brain's negative feedback system. The CNS endocannabinoid system consists of cannabinoid receptors, their endogenous ligands and enzymes for the synthesis and degradation of endocannabinoids. It participates crucially in neuronal cell-cell-communication and signal transduction, e.g., by modulating synaptic input and protecting neurons from excitotoxic damage. Over the last decade, it has also become evident that endocannabinoids play an important role in the communication between immune cells, and in the interaction between nerve and immune system during CNS damage. Thus, therapeutic intervention in the CNS endocannabinoid system may help to restore the well-controlled and finely tuned balance of immune reactions in pathological conditions.

Cachexia: pathophysiology and clinical relevance

Cachexia causes weight loss and increased mortality. It affects more than 5 million persons in the United States. Other causes of weight loss include anorexia, sarcopenia, and dehydration. The pathophysiology of cachexia is reviewed in this article. The major cause appears to be cytokine excess. Other potential mediators include testosterone and insulin-like growth factor I deficiency, excess myostatin, and excess glucocorticoids. Numerous diseases can result in cachexia, each by a slightly different mechanism. Both nutritional support and orexigenic agents play a role in the management of cachexia.