Safety and Efficacy of Lenabasum in a Phase II, Randomized, Placebo-Controlled Trial in Adults With Systemic Sclerosis

Cannabis therapy in rheumatological diseases: A systematic review

Cannabis has been used in rheumatic diseases as therapy for chronic pain or inflammatory conditions. Herein, the authors systematically review the rheumatological diseases in which cannabis has been studied: systemic sclerosis, fibromyalgia, osteoarthritis, rheumatoid arthritis, osteoporosis, polymyalgia rheumatica, gout, dermatomyositis, and psoriatic arthritis. We systematically searched PubMed for articles on cannabis and rheumatic diseases between 1966 and March 2023. Twenty-eight articles have been selected for review. Most of them (n=13) were on fibromyalgia and all of them but one showed important reduction in pain; sleep and mood also improved. On rheumatoid arthritis, two papers displayed decrease in pain and in one of them a reduction in inflammatory parameters was found. In scleroderma there was a case description with good results, one study on local use for digital ulcers also with good outcomes and a third one, that disclosed good results for skin fibrosis. In dermatomyositis a single study showed improvement of skin manifestations and in osteoarthritis (3 studies) this drug has demonstrated a good analgesic effect. Several surveys (n=5) on the general use of cannabis showed that rheumatological patients (mixed diseases) do use this drug even without medical supervision. The reported side effects were mild. In conclusion, cannabis treatment is an interesting option for the treatment of rheumatological diseases that should be further explored with more studies.

The Impact of the CB2 Cannabinoid Receptor in Inflammatory Diseases: An Update

The emergence of inflammatory diseases is a heavy burden on modern societies. Cannabis has been used for several millennia to treat inflammatory disorders such as rheumatism or gout. Since the characterization of cannabinoid receptors, CB1 and CB2, the potential of cannabinoid pharmacotherapy in inflammatory conditions has received great interest. Several studies have identified the importance of these receptors in immune cell migration and in the production of inflammatory mediators. As the presence of the CB2 receptor was documented to be more predominant in immune cells, several pharmacological agonists and antagonists have been designed to treat inflammation. To better define the potential of the CB2 receptor, three online databases, PubMed, Google Scholar and clinicaltrial.gov, were searched without language restriction. The full texts of articles presenting data on the endocannabinoid system, the CB2 receptor and its role in modulating inflammation in vitro, in animal models and in the context of clinical trials were reviewed. Finally, we discuss the clinical potential of the latest cannabinoid-based therapies in inflammatory diseases.

Cannabinoid CB2 receptor orthologues; in vitro function and perspectives for preclinical to clinical translation

Cannabinoid CB2 receptor agonists are in development as therapeutic agents, including for immune modulation and pain relief. Despite promising results in rodent preclinical studies, efficacy in human clinical trials has been marginal to date. Fundamental differences in ligand engagement and signalling responses between the human CB2 receptor and preclinical model species orthologues may contribute to mismatches in functional outcomes. This is a tangible possibility for the CB2 receptor in that there is a relatively large degree of primary amino acid sequence divergence between human and rodent. Here, we summarise CB2 receptor gene and protein structure, assess comparative molecular pharmacology between CB2 receptor orthologues, and review the current status of preclinical to clinical translation for drugs targeted at the CB2 receptor, focusing on comparisons between human, mouse and rat receptors. We hope that raising wider awareness of, and proposing strategies to address, this additional challenge in drug development will assist in ongoing efforts toward successful therapeutic translation of drugs targeted at the CB2 receptor. LINKED ARTICLES: This article is part of a themed issue Therapeutic Targeting of G Protein-Coupled Receptors: hot topics from the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists 2021 Virtual Annual Scientific Meeting. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.14/issuetoc.

Unmet needs in treating itch: reaching beyond eczema

PURPOSE

Pruritus is an unpleasant sensation that creates the urge to scratch. In many chronic conditions, relentless pruritus and scratching perpetuates a vicious itch-scratch cycle. Uncontrolled itch can detrimentally affect quality of life and may lead to sleep disturbance, impaired concentration, financial burden, and psychological suffering. Recent strides have been made to develop guidelines and investigate new therapies to treat some of the most common severely pruritic conditions, however, a large group of diseases remains underrecognized and undertreated. The purpose of this article is to provide a comprehensive review of the challenges hindering the treatment of pruritus.

METHODS

An online search was performed using PubMed, Web of Science, Google Scholar, and ClinicalTrials.gov from 1994 to 2024. Included studies were summarized and assessed for quality and relevance in treating pruritus.

RESULTS

Several barriers to treating pruritus emerged, including variable presentation, objective measurement of itch, and identifying therapeutic targets. Itch associated with autoimmune conditions, connective tissue diseases, genodermatoses, cutaneous T-cell lymphoma, and pruritus of unknown origin were among the etiologies with the greatest unmet needs.

CONCLUSION

Treating pruritus poses many challenges and there are many itchy conditions that have no yet been addressed. There is an urgent need for large-scale controlled studies to investigate potential targets for these conditions and novel therapies.

Vasoactive and Antifibrotic Properties of Cannabinoids and Applications to Vasospastic/Vaso-Occlusive Disorders: A Systematic Review

BACKGROUND

Management of vasospastic and vaso-occlusive disorders is a complex challenge, with current treatments showing varied success. Cannabinoids have demonstrated both vasodilatory and antifibrotic properties, which present potential mechanisms for therapeutic relief. No existing review examines these effects in peripheral circulation in relation to vasospastic and vaso-occlusive disorders. This study aims to investigate vasodilatory and antifibrotic properties of cannabinoids in peripheral vasculature for application in vasospastic and vaso-occlusive disorders affecting the hand.

METHODS

A systematic search was conducted by 2 independent reviewers across PubMed, Cochrane, Ovid MEDLINE, and CINAHL to identify studies in accordance with the determined inclusion/exclusion criteria. Information regarding study design, medication, dosage, and hemodynamic or antifibrotic effects were extracted. Descriptive statistics were used to summarize study findings as appropriate.

RESULTS

A total of 584 articles were identified, and 32 were selected for inclusion. Studies were grouped by effect type: hemodynamic (n = 17, 53%) and antifibrotic (n = 15, 47%). Vasodilatory effects including reduced perfusion pressure, increased functional capillary density, inhibition of vessel contraction, and increased blood flow were reported in 82% of studies. Antifibrotic effects including reduced dermal thickening, reduced collagen synthesis, and reduced fibroblast migration were reported in 100% of studies.

CONCLUSION

Overall, cannabinoids were found to have vasodilatory and antifibrotic effects on peripheral circulation via both endothelium-dependent and independent mechanisms. Our review suggests the applicability of cannabis-based medicines for vasospastic and vaso-occlusive disorders affecting the hand (eg, Raynaud disease, Buerger disease). Future research should aim to assess the effectiveness of cannabis-based medicines for these conditions.

Possible Role of Cannabis in the Management of Neuroinflammation in Patients with Post-COVID Condition

The post-COVID condition (PCC) is a pathology stemming from COVID-19, and studying its pathophysiology, diagnosis, and treatment is crucial. Neuroinflammation causes the most common manifestations of this disease including headaches, fatigue, insomnia, depression, anxiety, among others. Currently, there are no specific management proposals; however, given that the inflammatory component involves cytokines and free radicals, these conditions must be treated to reduce the current symptoms and provide neuroprotection to reduce the risk of a long-term neurodegenerative disease. It has been shown that cannabis has compounds with immunomodulatory and antioxidant functions in other pathologies. Therefore, exploring this approach could provide a viable therapeutic option for PCC, which is the purpose of this review. This review involved an exhaustive search in specialized databases including PubMed, PubChem, ProQuest, EBSCO, Scopus, Science Direct, Web of Science, and Clinical Trials. Phytocannabinoids, including cannabidiol (CBD), cannabigerol (CBG), and Delta-9-tetrahydrocannabinol (THC), exhibit significant antioxidative and anti-inflammatory properties and have been shown to be an effective treatment for neuroinflammatory conditions. These compounds could be promising adjuvants for PCC alone or in combination with other antioxidants or therapies. PCC presents significant challenges to neurological health, and neuroinflammation and oxidative stress play central roles in its pathogenesis. Antioxidant therapy and cannabinoid-based approaches represent promising areas of research and treatment for mitigating adverse effects, but further studies are needed.

Cannabinoids for the treatment of autoimmune and inflammatory skin diseases: A systematic review

In recent years, the medical use of cannabinoids has attracted growing attention worldwide. In particular, anti-inflammatory properties of cannabinoids led to their emergence as potential therapeutic options for autoimmune and inflammatory disorders. Recent studies have also shown that cannabinoid receptors are widely expressed and have endogenous ligands in the skin, suggesting that the skin has its own endocannabinoid system. The aim of this review is to discuss the potential therapeutic effects of cannabinoids in autoimmune and inflammatory skin diseases. Following an overview of cannabinoids and the endocannabinoid system, we describe the cellular and molecular mechanisms of cannabinoids in skin health and disease. We then review the clinical studies of cannabinoids in autoimmune and inflammatory skin diseases including systemic sclerosis (SSc), dermatomyositis (DM), psoriasis (Pso) and atopic dermatitis (AD). A primary literature search was conducted in July 2023, using PubMed and Web of Science. A total of 15 articles were included after excluding reviews, non-human studies and in vitro studies from 389 non-duplicated articles. Available evidence suggests that cannabinoids may be beneficial for SSc, DM, Pso and AD. However, further studies, ideally randomized controlled trials, are needed to further evaluate the use of cannabinoids in autoimmune and inflammatory skin diseases.

[Update on targeted biopharmaceuticals in systemic sclerosis!]

Systemic sclerosis (SSc) is a rare connective tissue disease characterized by inflammation, fibrosis, and autoimmunity. Despite few clinical trials when compared to other autoimmune diseases, SSc has benefited from renewed interest over the past ten years and a large number of clinical trials have been performed or are underway. We present here the results of the trials published in the last 5 years in ScS according to the chosen endpoint criteria and describe the trials in progress or expected in the years to come.

Composite measures to assess disease damage, disease severity and treatment response in systemic sclerosis clinical trials

PURPOSE OF REVIEW

The aim of this study was to summarize the composite outcome measures available to assess disease damage, severity and treatment response in systemic sclerosis (SSc).

RECENT FINDINGS

There have been many recent efforts to rigorously develop and validate composite outcome measures to assess the totality of the impact of SSc on patients. All initiatives have used both consensus and data-driven methods. Recently developed are a SSc-specific damage index, a patient-reported disease impact questionnaire (ScleroID) and a treatment response index (ACR-CRISS).

SUMMARY

Multiorgan, composite measures are being increasingly applied to assess treatment efficacy in clinical trials. Although a fully validated, disease-specific composite measure is not yet available, there has been significant recent progress towards developing measures of treatment response, damage and overall impact of SSc for application in randomized controlled trials.

Enrichment strategies for clinical trials targeting skin fibrosis and interstitial lung disease in systemic sclerosis

PURPOSE OF REVIEW

This review gives an update on enrichment strategies for clinical trials in patients with systemic sclerosis (SSc) in two contexts - skin fibrosis in early diffuse cutaneous disease, and SSc-related interstitial lung disease (ILD) - focusing on reports from the last 18 months. Lessons have been learnt from recent studies, making this review timely.

RECENT FINDINGS

Recent trials have highlighted how patients included into trials must be carefully selected to include 'progressors', that is, those most likely to benefit from treatment, and how drug mechanism action of action will influence trial design. For skin fibrosis, current enrichment strategies are mainly on clinical grounds (including disease duration, extent of skin thickening, tendon friction rubs and anti-RNA polymerase III positivity). Gene expression signatures may play a role in the future. For ILD, current enrichment strategies (degree of lung involvement as assessed by pulmonary function and high-resolution computed tomography) may help to recruit the most informative patients, but should avoid being too stringent to be feasible or for findings to be generalizable.

SUMMARY

Both skin fibrosis and ILD trials are challenging in SSc. Ongoing work on enrichment strategies should help to differentiate effective new treatments from placebo with smaller sample sizes than have been included in recent studies.

Efficacy and Safety of Lenabasum, a Cannabinoid Type 2 Receptor Agonist, in a Phase 3 Randomized Trial in Diffuse Cutaneous Systemic Sclerosis

OBJECTIVE

This phase 3 study was undertaken to investigate the efficacy and safety of lenabasum, a cannabinoid type 2 receptor agonist, in patients with diffuse cutaneous systemic sclerosis (dcSSc).

METHODS

A multinational double-blind study was conducted in 365 dcSSc patients who were randomized and dosed 1:1:1 with lenabasum 20 mg, lenabasum 5 mg, or placebo, each twice daily and added to background treatments, including immunosuppressive therapies (IST).

RESULTS

The primary end point, the American College of Rheumatology combined response index in dcSSc (CRISS) at week 52 for lenabasum 20 mg twice a day versus placebo, was not met, with CRISS score of 0.888 versus 0.887 (P = 0.4972, using mixed models repeated measures [MMRM]). The change in the modified Rodnan skin thickness score (MRSS) at week 52 for lenabasum 20 mg twice a day versus placebo was -6.7 versus -8.1 (P = 0.1183, using MMRM). Prespecified analyses showed higher CRISS scores, greater improvement in MRSS, and lower decline in forced vital capacity in patients on background mycophenolate and those who were taking IST for ≤1 year. No deaths or excess in serious or severe adverse events related to lenabasum were observed.

CONCLUSION

A benefit of lenabasum in dcSSc was not demonstrated. Most patients were treated with background IST, and treatment with mycophenolate mofetil in particular was associated with better outcomes. These findings support the use of IST in the treatment of dcSSc and highlight the challenge of demonstrating a treatment effect when investigational treatment is added to standard of care IST. These findings have relevance to trial design in SSc, as well as to clinical care.

Positive feedback loops between fibroblasts and the mechanical environment contribute to dermal fibrosis

Dermal fibrosis is characterized by excessive deposition of extracellular matrix in the dermis and affects millions of people worldwide and causes limited movement, disfigurement and psychological distress in patients. Fibroblast dysfunction of plays a central role in the pathogenesis of dermal fibrosis and is controlled by distinct factors. Recent studies support the hypothesis that fibroblasts can drive matrix deposition and stiffening, which in turn can exacerbate the functional dysregulation of fibroblasts. Ultimately, through a positive feedback loop, uncontrolled pathological fibrosis develops. This review aims to summarize the phenomenon and mechanism of the positive feedback loop in dermal fibrosis, and discuss potential therapeutic targets to help further elucidate the pathogenesis of dermal fibrosis and develop therapeutic strategies. In this review, fibroblast-derived compositional and structural changes in the ECM that lead to altered mechanical properties are briefly discussed. We focus on the mechanisms by which mechanical cues participate in dermal fibrosis progression. The mechanosensors discussed in the review include integrins, DDRs, proteoglycans, and mechanosensitive ion channels. The FAK, ERK, Akt, and Rho pathways, as well as transcription factors, including MRTF and YAP/TAZ, are also discussed. In addition, we describe stiffness-induced biological changes in the ECM on fibroblasts that contribute to the formation of a positive feedback loop. Finally, we discuss therapeutic strategies to treat the vicious cycle and present important suggestions for researchers conducting in-depth research.

Drug development and novel therapeutics to ensure a personalized approach in the treatment of systemic sclerosis

INTRODUCTION

Systemic sclerosis (SSc) is a systemic disease encompassing autoimmunity, vasculopathy, and fibrosis. SSc is still burdened by high mortality and morbidity rates. Recent advances in understanding the pathogenesis of SSc have identified novel potential therapeutic targets. Several clinical trials have been subsequently designed to evaluate the efficacy of a number of new drugs. The aim of this review is to provide clinicians with useful information about these novel molecules.

AREA COVERED

In this narrative review, we summarize the available evidence regarding the most promising targeted therapies currently under investigation for the treatment of SSc. These medications include kinase inhibitors, B-cell depleting agents, and interleukin inhibitors.

EXPERT OPINION

Over the next five years, several new, targeted drugs will be introduced in clinical practice for the treatment of SSc. Such pharmacological agents will expand the existing pharmacopoeia and enable a more personalized and effective approach to patients with SSc. Thus, it will not only possible to target a specific disease domain, but also different stages of the disease.

Clinical Phenotypes of Patients With Systemic Sclerosis With Distinct Molecular Signatures in Skin

OBJECTIVE

Systemic sclerosis (SSc) patients are classified according to degree of skin fibrosis (limited and diffuse cutaneous [lc and dc]) and serum autoantibodies. We undertook the present multicenter study to determine whether intrinsic subset (IS) classification based upon skin gene expression yields additional valuable clinical information.

METHODS

SSc patients and healthy participants (HPs) were classified into Normal-like, Limited, Fibroproliferative, and Inflammatory ISs using a previously trained classifier. Clinical data were obtained (serum autoantibodies, pulmonary function testing, modified Rodnan skin thickness scores [mRSS], and high-resolution chest computed tomography [HRCT]). Statistical analyses were performed to compare patients classified by IS, traditional cutaneous classification, and serum autoantibodies.

RESULTS

A total of 223 participants (165 SSc [115 dcSSc and 50 lcSSc] and 58 HPs) were classified. Inflammatory IS patients had higher mRSS (22.1 ± 9.9; P < 0.001) than other ISs and dcSSc patients (19.4 ± 9.4; P = 0.05) despite similar disease duration (median [interquartile range] months 14.9 [19.9] vs. 18.4 [31.6]; P = 0.48). In multivariable modeling, no significant association between mRSS and RNA polymerase III (P = 0.07) or anti-topoisomerase I (Scl-70) (P = 0.09) was found. Radiographic interstitial lung disease (ILD) was more prevalent in Fibroproliferative IS compared with other ISs (91%; P = 0.04) with similar prevalence between lcSSc and dcSSc (67% vs. 76%; P = 0.73). Positive Scl-70 antibody was the strongest ILD predictor (P < 0.001). Interestingly, all lcSSc/Fibroproliferative patients demonstrated radiographic ILD.

CONCLUSIONS

Classification by IS identifies patients with distinct clinical phenotypes versus traditional cutaneous or autoantibody classification. IS classification identifies subgroups of SSc patients with more radiographic ILD (Fibroproliferative), higher mRSS (Inflammatory), and milder phenotype (Normal-like) and may provide additional clinically useful information to current SSc classification systems.

Investigational drugs for the treatment of scleroderma: what's new?

INTRODUCTION

Systemic sclerosis (SSc) is an orphan, chronic, autoimmune, fibrotic disease with unknown etiology characterized by progressive fibrosis of the skin and internal organs. SSc has the highest mortality, the deadliest among the connective tissue diseases, despite the introduction of new treatment options in the past decades.

AREAS COVERED

The aim of the current systematic review was to investigate new targeted therapy and their impact on disease progression, mainly focusing on phase I and II clinical trials within the past three years.

EXPERT OPINION

Despite recent groundbreaking advancements in understanding SSc pathophysiology, early diagnosis and early introduction of effective targeted treatments within the optimal window of opportunity to prevent irreversible disease damage still represents a significant clinical challenge. Ongoing significant research for new molecular and epigenetics pathways is of fundamental importance to offer new perspectives on disease phenotype and for the development of personalized treatment strategies.

Therapeutic Approaches to Systemic Sclerosis: Recent Approvals and Future Candidate Therapies

Systemic sclerosis is the rheumatic disease with the highest individual mortality. The severity of the disease is determined by the extent of fibrotic changes to cutaneous and internal organ tissues, the most life-threatening visceral manifestations being interstitial lung disease, SSc-associated-pulmonary arterial hypertension and myocardial involvement. The heterogeneity of the disease has initially hindered the design of successful clinical trials, but considerations on classification criteria have improved patient selection in trials, allowing the identification of more homogeneous groups of patients based on progressive visceral manifestations or the extent of skin involvement with a focus of patients with early disease. Two major subsets of systemic sclerosis are classically described: limited cutaneous systemic sclerosis characterized by distal skin fibrosis and the diffuse subset with distal and proximal skin thickening. Beyond this dichotomic subgrouping of systemic sclerosis, new phenotypic considerations based on antibody subtypes have provided a better understanding of the heterogeneity of the disease, anti-Scl70 antibodies being associated with progressive interstitial lung disease regardless of cutaneous involvement. Two targeted therapies, tocilizumab (a monoclonal antibody targeting interleukin-6 receptors (IL-6R)) and nintedanib (a tyrosine kinase inhibitor), have recently been approved by the American Food & Drug Administration to limit the decline of lung function in patients with SSc-associated interstitial lung disease, demonstrating that such better understanding of the disease pathogenesis with the identification of key targets can lead to therapeutic advances in the management of some visceral manifestations of the disease. This review will provide a brief overview of the pathogenesis of SSc and will present a selection of therapies recently approved or evaluated in this context. Therapies evaluated and approved in SSc-ILD will be emphasized and a review of recent phase II trials in diffuse cutaneous systemic sclerosis will be proposed. We will also discuss selected therapeutic pathways currently under investigation in systemic sclerosis that still lack clinical data in this context but that may show promising results in the future based on preclinical data.

Scleroderma Skin: How Is Treatment Best Guided by Data and Implemented in Clinical Practice?

As skin involvement is the hall mark of systemic sclerosis (SSc) and changes of skin involvement have shown to correlate with internal organ involvement, assessing the extend of skin involvement is key. Although the modified Rodnan skin score is a validated tool used to evaluate the skin in SSc, it has its drawbacks. Novel imagine methods are promising but should be further evaluated. As for molecule markers for skin progression there are conflicting data on the predictive significance of baseline SSc skin gene expression profiles, but immune cell type signature in SSc skin correlates with progression.

State-of-the-art evidence in the treatment of systemic sclerosis

Systemic sclerosis (SSc) is a rare autoimmune connective tissue disease with multi-organ involvement, fibrosis and vasculopathy. Treatment in SSc, including early diffuse cutaneous SSc (dcSSc) and the use of organ-specific therapies, has improved, as evident from randomized clinical trials. Treatments for early dcSSc include immunosuppressive agents such as mycophenolate mofetil, methotrexate, cyclophosphamide, rituximab and tocilizumab. Patients with rapidly progressive early dcSSc might be eligible for autologous haematopoietic stem cell transplantation, which can improve survival. Morbidity from interstitial lung disease and pulmonary arterial hypertension is improving with the use of proven therapies. Mycophenolate mofetil has surpassed cyclophosphamide as the initial treatment for SSc-interstitial lung disease. Nintedanib and possibly perfinidone can be considered in SSc pulmonary fibrosis. Pulmonary arterial hypertension is frequently treated with initial combination therapy (for example, with phosphodiesterase 5 inhibitors and endothelin receptor antagonists) and, if necessary, the addition of a prostacyclin analogue. Raynaud phenomenon and digital ulcers are treated with dihydropyridine calcium channel blockers (especially nifedipine), then phosphodiesterase 5 inhibitors or intravenous iloprost. Bosentan can reduce the development of new digital ulcers. Trial data for other manifestations are mostly lacking. Research is needed to develop targeted and highly effective treatments, best practices for organ-specific screening and early intervention, and sensitive outcome measurements.

Differentially expressed genes in systemic sclerosis: Towards predictive medicine with new molecular tools for clinicians

Systemic sclerosis (SSc) is a rare and chronic autoimmune disease characterized by a pathogenic triad of immune dysregulation, vasculopathy, and progressive fibrosis. Clinical tools commonly used to assess patients, such as the modified Rodnan skin score, difference between limited or diffuse forms of skin involvement, presence of lung, heart or kidney involvement, or of various autoantibodies, are important prognostic factors, but still fail to reflect the large heterogeneity of the disease. SSc treatment options are diverse, ranging from conventional drugs to autologous hematopoietic stem cell transplantation, and predicting response is challenging. Genome-wide technologies, such as high throughput microarray analyses and RNA sequencing, allow accurate, unbiased, and broad assessment of alterations in expression levels of multiple genes. In recent years, many studies have shown robust changes in the gene expression profiles of SSc patients compared to healthy controls, mainly in skin tissues and peripheral blood cells. The objective analysis of molecular patterns in SSc is a powerful tool that can further classify SSc patients with similar clinical phenotypes and help predict response to therapy. In this review, we describe the journey from the first discovery of differentially expressed genes to the identification of enriched pathways and intrinsic subsets identified in SSc, using machine learning algorithms. Finally, we discuss the use of these new tools to predict the efficacy of various treatments, including stem cell transplantation. We suggest that the use of RNA gene expression-based classifications according to molecular subsets may bring us one step closer to precision medicine in Systemic Sclerosis.

Systemic sclerosis

Systemic sclerosis, also known as scleroderma, is a rare and complex autoimmune connective-tissue disease. Once considered an untreatable and unpredictable condition, research advancements have improved our understanding of its disease pathogenesis and clinical phenotypes and expanded our treatment armamentarium. Early and accurate diagnosis is essential, while ongoing efforts to risk stratify patients have a central role in predicting both organ involvement and disease progression. A holistic approach is required when choosing the optimal therapeutic strategy, balancing the side-effect profile with efficacy and tailoring the treatment according to the goals of care of the patient. This Seminar reviews the multiple clinical dimensions of systemic sclerosis, beginning at a precursor very early stage of disease, with a focus on timely early detection of organ involvement. This Seminar also summarises management considerations according to the pathological hallmarks of systemic sclerosis (eg, inflammation, fibrosis, and vasculopathy) and highlights unmet needs and opportunities for future research and discovery.

Systemic sclerosis

Systemic sclerosis, also known as scleroderma, is a rare and complex autoimmune connective-tissue disease. Once considered an untreatable and unpredictable condition, research advancements have improved our understanding of its disease pathogenesis and clinical phenotypes and expanded our treatment armamentarium. Early and accurate diagnosis is essential, while ongoing efforts to risk stratify patients have a central role in predicting both organ involvement and disease progression. A holistic approach is required when choosing the optimal therapeutic strategy, balancing the side-effect profile with efficacy and tailoring the treatment according to the goals of care of the patient. This Seminar reviews the multiple clinical dimensions of systemic sclerosis, beginning at a precursor very early stage of disease, with a focus on timely early detection of organ involvement. This Seminar also summarises management considerations according to the pathological hallmarks of systemic sclerosis (eg, inflammation, fibrosis, and vasculopathy) and highlights unmet needs and opportunities for future research and discovery.

Microglial Cannabinoid CB2 Receptors in Pain Modulation

Pain, especially chronic pain, can strongly affect patients' quality of life. Cannabinoids ponhave been reported to produce potent analgesic effects in different preclinical pain models, where they primarily function as agonists of G_i/o protein-coupled cannabinoid CB₁ and CB₂ receptors. The CB₁ receptors are abundantly expressed in both the peripheral and central nervous systems. The central activation of CB₁ receptors is strongly associated with psychotropic adverse effects, thus largely limiting its therapeutic potential. However, the CB₂ receptors are promising targets for pain treatment without psychotropic adverse effects, as they are primarily expressed in immune cells. Additionally, as the resident immune cells in the central nervous system, microglia are increasingly recognized as critical players in chronic pain. Accumulating evidence has demonstrated that the expression of CB₂ receptors is significantly increased in activated microglia in the spinal cord, which exerts protective consequences within the surrounding neural circuitry by regulating the activity and function of microglia. In this review, we focused on recent advances in understanding the role of microglial CB₂ receptors in spinal nociceptive circuitry, highlighting the mechanism of CB₂ receptors in modulating microglia function and its implications for CB₂ receptor- selective agonist-mediated analgesia.

The Role of Myofibroblasts in Physiological and Pathological Tissue Repair

Myofibroblasts are the construction workers of wound healing and repair damaged tissues by producing and organizing collagen/extracellular matrix (ECM) into scar tissue. Scar tissue effectively and quickly restores the mechanical integrity of lost tissue architecture but comes at the price of lost tissue functionality. Fibrotic diseases caused by excessive or persistent myofibroblast activity can lead to organ failure. This review defines myofibroblast terminology, phenotypic characteristics, and functions. We will focus on the central role of the cell, ECM, and tissue mechanics in regulating tissue repair by controlling myofibroblast action. Additionally, we will discuss how therapies based on mechanical intervention potentially ameliorate wound healing outcomes. Although myofibroblast physiology and pathology affect all organs, we will emphasize cutaneous wound healing and hypertrophic scarring as paradigms for normal tissue repair versus fibrosis. A central message of this review is that myofibroblasts can be activated from multiple cell sources, varying with local environment and type of injury, to either restore tissue integrity and organ function or create an inappropriate mechanical environment.

Cannabinoid Compounds as a Pharmacotherapeutic Option for the Treatment of Non-Cancer Skin Diseases

The endocannabinoid system has been shown to be involved in various skin functions, such as melanogenesis and the maintenance of redox balance in skin cells exposed to UV radiation, as well as barrier functions, sebaceous gland activity, wound healing and the skin's immune response. In addition to the potential use of cannabinoids in the treatment and prevention of skin cancer, cannabinoid compounds and derivatives are of interest as potential systemic and topical applications for the treatment of various inflammatory, fibrotic and pruritic skin conditions. In this context, cannabinoid compounds have been successfully tested as a therapeutic option for the treatment of androgenetic alopecia, atopic and seborrhoeic dermatitis, dermatomyositis, asteatotic and atopic eczema, uraemic pruritis, scalp psoriasis, systemic sclerosis and venous leg ulcers. This review provides an insight into the current literature on cannabinoid compounds as potential medicines for the treatment of skin diseases.

Patient and Physician Global Assessments of Disease Status in Systemic Sclerosis

Global assessments of disease by both patients and physicians are widely used in clinical studies of systemic sclerosis (SSc). They are commonly secondary end points in randomized controlled trials (RCTs) and are considered important items in composite measures of treatment response. A comprehensive literature review was conducted of the formats, wording, and clinimetric properties of the patient global assessment of disease status (PtGA) and physician global assessment of disease status (PhGA) used in RCTs of SSc. Marked heterogeneity was found in the wording and measurement scales of the global assessments applied in RCTs. These instruments were not developed using rigorous methodology and have not been fully validated. There is a pressing need for standardization and validation of patient and physician global assessment tools in SSc to enable universal application of these measures across RCTs in SSc.

Diagnosis and Management of Cutaneous Manifestations of Autoimmune Connective Tissue Diseases

The cutaneous features of autoimmune connective tissue disease pose a unique challenge to patients and clinicians managing these conditions. In this review, we outline the key elements of diagnosis and treatment of cutaneous lupus erythematosus, dermatomyositis, systemic sclerosis, and morphea. This article also aims to present an update on gold standard as well as new and emerging therapies for these conditions. Overall, dermatologists can play a key role in diagnosing and treating autoimmune connective tissue diseases and this review intends to provide an up-to-date toolkit to guide clinical dermatologists in this endeavor.

Safety and Efficacy of Lenabasum, a Cannabinoid Receptor Type 2 Agonist, in Patients with Dermatomyositis with Refractory Skin Disease: A Randomized Clinical Trial

BACKGROUND

Treatment options are limited for skin disease in dermatomyositis. Lenabasum is a cannabinoid receptor type 2 agonist that triggers the resolution of inflammation.

OBJECTIVE

The objective of this study was to evaluate the safety and efficacy of lenabasum in patients with refractory cutaneous dermatomyositis.

DESIGN

This study was a single-center, double-blind, randomized, placebo-controlled phase 2 study conducted from July 2015 to August 2017.

POPULATION

The population included subjects aged ≥18 years with at least moderately active dermatomyositis skin activity by Cutaneous Dermatomyositis Disease Area and Severity Index activity ≥ 14 and failure or intolerance to hydroxychloroquine.

INTERVENTION

Participants received 20 mg lenabasum daily for 28 days and then 20 mg twice per day for 56 days or placebo.

MAIN OUTCOMES AND MEASURES

The primary outcome was a change in Cutaneous Dermatomyositis Disease Area and Severity Index activity. Safety and other secondary efficacy assessments were performed till day 113.

RESULTS

A total of 22 subjects were randomized to lenabasum (n = 11) or placebo (n = 11). No serious or severe adverse events were related to lenabasum, and no participants discontinued the study. The adjusted least-squares mean for Cutaneous Dermatomyositis Disease Area and Severity Index activity decreased more for lenabasum, and the difference was significant on day 113 (least-squares mean [standard error] difference = ‒6.5 [3.1], P = 0.038). Numerically greater improvements were seen in multiple secondary efficacy outcomes and biomarkers with lenabasum.

CONCLUSION

Lenabasum treatment was well tolerated and was associated with greater improvement in Cutaneous Dermatomyositis Disease Area and Severity Index activity and multiple efficacy outcomes.

TRIAL REGISTRATION

This study was registered at ClinicalTrials.gov, NCT02466243.

Activating cannabinoid receptor 2 preserves axonal health through GSK-3β/NRF2 axis in adrenoleukodystrophy

Aberrant endocannabinoid signaling accompanies several neurodegenerative disorders, including multiple sclerosis. Here, we report altered endocannabinoid signaling in X-linked adrenoleukodystrophy (X-ALD), a rare neurometabolic demyelinating syndrome caused by malfunction of the peroxisomal ABCD1 transporter, resulting in the accumulation of very long-chain fatty acids (VLCFAs). We found abnormal levels of cannabinoid receptor 2 (CB2r) and related endocannabinoid enzymes in the brain and peripheral blood mononuclear cells (PBMCs) of X-ALD patients and in the spinal cord of a murine model of X-ALD. Preclinical treatment with a selective agonist of CB2r (JWH133) halted axonal degeneration and associated locomotor deficits, along with normalization of microgliosis. Moreover, the drug improved the main metabolic disturbances underlying this model, particularly in redox and lipid homeostatic pathways, including increased lipid droplets in motor neurons, through the modulation of the GSK-3β/NRF2 axis. JWH133 inhibited Reactive Oxygen Species elicited by excess VLCFAs in primary microglial cultures of Abcd1-null mice. Furthermore, we uncovered intertwined redox and CB2r signaling in the murine spinal cords and in patient PBMC samples obtained from a phase II clinical trial with antioxidants (NCT01495260). These findings highlight CB2r signaling as a potential therapeutic target for X-ALD and perhaps other neurodegenerative disorders that present with dysregulated redox and lipid homeostasis.

Lenabasum Reduces Porphyromonas gingivalis-Driven Inflammation

The aim of this study was to evaluate the potential anti-inflammatory and anti-resorptive effects of lenabasum in the context of Porphyromonas gingivalis (Pg)-induced inflammation. Lenabasum or ajulemic acid (1',1'-dimethylheptyl-THC-11-oic-acid), a synthetic analog of THC-11-oic acid, has already demonstrated anti-inflammatory properties for the treatment of several inflammatory diseases. In vitro, the cytocompatibility of lenabasum was evaluated in human oral epithelial cells (EC), oral fibroblasts and osteoblasts by metabolic activity assay. The effect of lenabasum (5 µM) treatment of Pg-LPS- and P. gingivalis-infected EC on the pro- and anti-inflammatory markers was studied through RTqPCR. In vivo, lenabasum was injected subcutaneously in a P. gingivalis-induced calvarial abscess mouse model to assess its pro-healing effect. Concentrations of lenabasum up to 5 µM were cytocompatible in all cell types. Treatment of Pg-LPS and Pg-infected EC with lenabasum (5 µM; 6 h) reduced the gene expression of TNF-α, COX-2, NF-κB, and RANKL, whereas it increased the expression of IL-10 and resolvin E1 receptor respectively (p < 0.05). In vivo, the Pg-elicited inflammatory lesions' clinical size was significantly reduced by lenabasum injection (30 µM) vs untreated controls (45%) (p < 0.05). Histomorphometric analysis exhibited improved quantity and quality of bone (with reduced lacunae) and significantly reduced calvarial soft tissue inflammatory score in mice treated with lenabasum (p < 0.05). Tartrate-resistant acid phosphatase activity assay (TRAP) also demonstrated decreased osteoclastic activity in the treatment group compared to that in the controls. Lenabasum showed promising anti-inflammatory and pro-resolutive properties in the management of Pg-elicited inflammation, and thus, its potential as adjuvant periodontal treatment should be further investigated.

Developing the Cannabinoid Receptor 2 (CB2) pharmacopoeia: past, present, and future

Cannabinoid Receptor 2 (CB2) is a G protein-coupled receptor (GPCR) with considerable, though as yet unrealised, therapeutic potential. Promising preclinical data supports the applicability of CB2 activation in autoimmune and inflammatory diseases, pain, neurodegeneration, and osteoporosis. A diverse pharmacopoeia of cannabinoid ligands is available, which has led to considerable advancements in the understanding of CB2 function and extensive preclinical evaluation. However, until recently, most CB2 ligands were highly lipophilic and as such not optimal for clinical application due to unfavourable physicochemical properties. A number of strategies have been applied to develop CB2 ligands to achieve closer to 'drug-like' properties and a few such compounds have now undergone clinical trial. We review the current state of CB2 ligand development and progress in optimising physicochemical properties, understanding advanced molecular pharmacology such as functional selectivity, and clinical evaluation of CB2-targeting compounds.

JAK1/2 Inhibitor Baricitinib Improves Skin Fibrosis and Digital Ulcers in Systemic Sclerosis

Background

Systemic sclerosis (SSc) is a rare disabling connective tissue disease with few available treatment options. Diffuse cutaneous systemic sclerosis (dcSSc) is associated with high mortality. A previous experiment has shown that JAK2 inhibitor can significantly improve skin fibrosis in bleomycin (BLM)-induced murine model, including reducing dermal thickening and collagen accumulation. We aimed to describe the efficacy of oral JAK1/2 inhibitor baricitinib in SSc patients, especially focusing on skin fibrosis and microvascular manifestations.

Methods

We described the different effects of oral selective JAK1, JAK2, or JAK3 inhibitor treatment in a BLM-induced skin fibrosis mouse model. Furthermore, 10 adult patients with dcSSc were treated with baricitinib. We assessed the changes in modified rodman skin score (mRSS) and digital ulcer net burden at week 12 and 24 from baseline. We also compared the absolute changes in scores on the Scleroderma Health Assessment Questionnaire (SHAQ) and a total score on the St. George's Respiratory Questionnaire (SGRQ) over a 24-week period.

Results

In the experimental mouse model of skin fibrosis, a JAK1 and JAK2 inhibitor ameliorated skin fibrosis, and a JAK2 inhibitor had the most obvious effect. Treatment with the JAK2 inhibitor also blunted the capillary rarefaction. We demonstrated that skin fibrosis and digital ulcers were significantly relieved in 10 SSc patients treated with baricitinib. The mRSS significantly improved at week 12 from baseline, with a mean change in mRSS of -8.3 [95% confidence interval (CI), -12.03 to -4.574; p = 0.0007] and improved greater at week 24 to -11.67 (95% CI, -16.84 to -6.496; p = 0.0008). Among the four patients with digital ulcers (DU), three were completely healed at week 24, the number of ulcers in another patient was significantly reduced, and there was no patient with new ulcers. Only one adverse event (AE) of herpes zoster was observed.

Conclusions

Our results indicate that selective JAK1 and JAK2 inhibitor alleviates skin fibrosis, and oral JAK1/2 inhibitor baricitinib is a potentially effective treatment for dcSSc patients with skin fibrosis and DU. Baricitinib was well-tolerated by most patients in this study. Additional large clinical trials are needed to confirm our pilot findings.

Chinese Clinical Trial Registry Number

ChiCTR2000030995.

Skin involvement in early diffuse cutaneous systemic sclerosis: an unmet clinical need

Diffuse cutaneous systemic sclerosis (dcSSc) is associated with high mortality resulting from early internal-organ involvement. Clinicians therefore tend to focus on early diagnosis and treatment of potentially life-threatening cardiorespiratory and renal disease. However, the rapidly progressive painful, itchy skin tightening that characterizes dcSSc is the symptom that has the greatest effect on patients' quality of life, and there is currently no effective disease-modifying treatment for it. Considerable advances have been made in predicting the extent and rate of skin-disease progression (which vary between patients), including the development of techniques such as molecular analysis of skin biopsy samples. Risk stratification for progressive skin disease is especially relevant now that haematopoietic stem-cell transplantation is a treatment option, because stratification will inform the balance of risk versus benefit for each patient. Measurement of skin disease is a major challenge. Results from clinical trials have highlighted limitations of the modified Rodnan skin score (the current gold standard). Alternative patient-reported and other potential outcome measures have been and are being developed. Patients with early dcSSc should be referred to specialist centres to ensure best-practice management, including the management of their skin disease, and to maximize opportunities for inclusion in clinical trials.

Cannabinoids for the Treatment of Dermatologic Conditions

In recent years, cannabinoid (CB) products have gained popularity among the public. The anti-inflammatory properties of CBs have piqued the interest of researchers and clinicians because they represent promising avenues for the treatment of autoimmune and inflammatory skin disorders that may be refractory to conventional therapy. The objective of this study was to review the existing literature regarding CBs for dermatologic conditions. A primary literature search was conducted in October 2020, using the PubMed and Embase databases, for all articles published from 1965 to October 2020. Review articles, studies using animal models, and nondermatologic and pharmacologic studies were excluded. From 248 nonduplicated studies, 26 articles were included. There were 13 articles on systemic CBs and 14 reports on topical CBs. Selective CB receptor type 2 agonists were found to be effective in treating diffuse cutaneous systemic sclerosis and dermatomyositis. Dronabinol showed efficacy for trichotillomania. Sublingual cannabidiol and Δ-9-tetrahydrocannabinol were successful in treating the pain associated with epidermolysis bullosa. Available evidence suggests that CBs may be effective for the treatment of various inflammatory skin disorders. Although promising, additional research is necessary to evaluate efficacy and to determine dosing, safety, and long-term treatment guidelines.

Emerging Evidence and Treatment Perspectives from Randomized Clinical Trials in Systemic Sclerosis: Focus on Interstitial Lung Disease

Systemic sclerosis (SSc) is a complex rare autoimmune disease with heterogeneous clinical manifestations. Currently, interstitial lung disease (ILD) and cardiac involvement (including pulmonary arterial hypertension) are recognized as the leading causes of SSc-associated mortality. New molecular targets have been discovered and phase II and phase III clinical trials published in the last 5 years on SSc-ILD will be discussed in this review. Details on the study design; the drug tested and its dose; the inclusion and exclusion criteria of the study; the concomitant immunosuppression; the outcomes and the duration of the study were reviewed. The two most common drugs used for the treatment of SSc-ILD are cyclophosphamide and mycophenolate mofetil, both supported by randomized controlled trials. Additional drugs, such as nintedanib and tocilizumab, have been approved to slow pulmonary function decline in SSc-ILD. In this review, we discuss the therapeutic alternatives for SSc management, offering the option to customize the design of future studies to stratify SSc patients and provide a patient-specific treatment according to the new emerging pathogenic features of SSc-ILD.

The role of antifibrotic therapies in the treatment of systemic sclerosis-associated interstitial lung disease

Systemic sclerosis (SSc) is a rare autoimmune condition with complex pathogenesis characterized by a heterogeneous presentation and different disease courses. Fibrosis of multiple organs including the lungs favored by inflammation and vasculopathy is the hallmark of SSc. SSc-associated interstitial lung disease (SSc-ILD) is common and can be associated with poor outcomes, this complication being the leading cause of death in recent series. Because of its huge heterogeneity, SSc-ILD management can be very challenging. Immunosuppressive therapy has long been used to prevent SSc-ILD progression with modest effects in clinical trials. However, thanks to a better understating of SSc pathogenesis, innovative therapies including antifibrotics are increasingly being developed. The achievement of the Safety and Efficacy of Nintedanib in Systemic SClerosIS (SENSCIS) trial has led to the approval by drug agencies of the first antifibrotic drug for SSc-ILD. In parallel, other antifibrotics are being investigated as possible beneficial therapies in SSc-ILD. An important unmet need remains to clarify the positioning of the various strategies, such as the added value of combination of immunosuppressants and antifibrotic therapies in patients at high risk of progression. Indeed, irreversible lung injury or self-perpetuated progression highlights the concept of a window of opportunity in SSc-ILD patients. Herewith, we provide an overview of the most significant clinical trials with antifibrotic drugs developed in recent years for the management of SSc-ILD and a viewpoint about their positioning in treatment algorithms.

Cannabinoid type 2 receptor (CB2R) distribution in dermatomyositis skin and peripheral blood mononuclear cells (PBMCs) and in vivo effects of LenabasumTM

Background

Lenabasum is a cannabinoid type 2 receptor (CB2R) reverse agonist that demonstrates anti-inflammatory effects in vivo and in vitro in dermatomyositis (DM) and is currently being investigated for therapeutic potential. The purpose of our study is to investigate CB2R distribution as well as the effects of lenabasum in DM.

Methods

Immunohistochemistry staining (IHC) was utilized to examine immune cell and cytokine production changes in lesional DM skin biopsies from lenabasum and placebo-treated patients. CB2R expression in various immune cell populations within DM skin was investigated with image mass cytometry (IMC), whereas flow cytometry elucidated CB2R expression in DM peripheral blood mononuclear cells (PBMCs) as well as cytokine production by CB2R-expressing cell populations.

Results

After 12 weeks of lenabasum treatment, IHC staining showed that CD4+ T cells, CB2R, IL-31, IFN-γ, and IFN-β cytokines were downregulated. IFN-γ and IFN-β mRNA decreased in lesional DM skin but not in PBMCs. IMC findings revealed that CB2R was upregulated in DM lesional skin compared to HC skin and DM PBMCs (p<0.05). In DM skin, CB2R was upregulated on dendritic cells, B cells, T cells, and macrophages while dendritic cells had the greatest expression in both DM skin and PBMCs (p<0.05). These CB2R+ cells in the skin produce IL-31, IL-4, IFN-γ, and IFN-β.

Conclusion

Our findings of differential CB2R expression based on location and cell type suggest modes by which lenabasum may exert anti-inflammatory effects in DM and highlights dendritic cells as potential therapeutic targets.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13075-021-02665-x.

Carbon-silicon switch led to the discovery of novel synthetic cannabinoids with therapeutic effects in a mouse model of multiple sclerosis

Cannabinoids are widely studied as therapeutic agents for the treatment of various diseases. Among them, THC and CBD are two important phytocannabinoids which have served as structural templates for the design of synthetic analogs. In this study, we designed and synthesized a variety of novel cannabinoids based on the structural backbones of THC and CBD using the carbon-silicon switch strategy. A dimethyl silyl group was introduced as the tail group and two series of novel compounds were designed and synthesized, which showed a wide range of binding affinity for CB1 and CB2 receptors. Among them, compound 15b was identified as a non-selective CB1 and CB2 agonist and 38b as a selective agonist for the CB2 receptor. Preliminary screening showed that both compounds have improved metabolic stability than their carbon analogs and good in vivo pharmacokinetic profiles. Furthermore, both 15b and 38b significantly alleviated the phenotype of experimental autoimmune encephalomyelitis (EAE) in mice.

Cellular and Molecular Diversity in Scleroderma

With the increasing armamentarium of high-throughput tools available at manageable cost, it is attractive and informative to determine the molecular underpinnings of patient heterogeneity in systemic sclerosis (SSc). Given the highly variable clinical outcomes of patients labelled with the same diagnosis, unravelling the cellular and molecular basis of disease heterogeneity will be crucial to predicting disease risk, stratifying management and ultimately informing a patient-centered precision medicine approach. Herein, we summarise the findings of the past several years in the fields of genomics, transcriptomics, and proteomics that contribute to unraveling the cellular and molecular heterogeneity of SSc. Expansion of these findings and their routine integration with quantitative analysis of histopathology and imaging studies into clinical care promise to inform a scientifically driven patient-centred personalized medicine approach to SSc in the near future.

Safety and Tolerability of Natural and Synthetic Cannabinoids in Older Adults: A Systematic Review and Meta-Analysis of Open-Label Trials and Observational Studies

BACKGROUND AND OBJECTIVE

Although cannabinoid-based medications are increasingly used by older adults, their safety and tolerability in this age group remain unclear. The purpose of this systematic review was to examine the safety and tolerability of cannabinoid-based medications by conducting a meta-analysis of open-label observational studies of cannabinoid-based medications for all indications in individuals with a mean age of ≥50 years.

METHODS

A systematic search was conducted on PubMed, PsycINFO, MEDLINE, EMBASE and CINHAL. Study quality was assessed using an adapted version of the Grading of Recommendations Assessment, Development and Evaluation criteria and Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed. We included studies that (a) were published from 1990 onwards; (b) included older adults (mean age ≥50 years); and (c) provided data on the safety and tolerability of medical cannabinoids. Data were pooled using a random-effects approach. Risk of adverse events, serious adverse events and withdrawals was computed as the incidence rate (IR). Separate analyses were conducted by the cannabinoid-based medication used, for delta-9-tetrahydrocannabinol (THC), cannabidiol (CBD) and a combination of THC and CBD (THC:CBD).

RESULTS

Thirty-eight studies were identified (THC = 23; CBD = 6; THC:CBD = 9; N = 2341, mean age: 63.19 ± 8.08 years, men: 53.86%). THC had a very low incidence of all-cause and treatment-related adverse events (IR: 122.18, 95% confidence interval [CI] 38.23-253.56; IR: 84.76, 95% CI 0.13-326.01, respectively) and negligible serious adverse events (IR = 0). Similar IRs for CBD (all cause, IR: 111.91, 95% CI 1.24-495.93; treatment related, IR: 1.76, 95% CI 4.63-23.05) and no serious adverse events (IR = 0). CBD was not associated with a risk of treatment-related withdrawals. THC had a low risk of all-cause and treatment-related withdrawals (IR: 25.18, 95% CI 12.35-42.52; IR: 7.83, 95% CI 3.26-14.38, respectively). The THC:CBD treatment had a low risk of all-cause and treatment-related adverse events (IR: 100.72, 95% CI 0.25-383.00; IR: 55.38, 95% CI 8.61-142.80, respectively), but reported a risk of all-cause and treatment-related serious adverse events (IR: 21.32, 95% CI 0.18-93.26; IR: 3.71, 95% CI 0.21-11.56, respectively), and all-cause and treatment-related withdrawals (IR: 78.63, 95% CI 17.43-183.90; IR: 34.31, 95% CI 6.09-85.52, respectively). Significant heterogeneity (I² >55%) was present in most analyses.

CONCLUSIONS

Although cannabinoid-based medications were generally safe and acceptable to adults aged over 50 years, these estimates are limited by the lack of a control condition and considerable heterogeneity. Nevertheless, they complement and are consistent with comparable evidence from randomised controlled trials.

New risk model is able to identify patients with a low risk of progression in systemic sclerosis

Objectives

To develop a prediction model to guide annual assessment of systemic sclerosis (SSc) patients tailored in accordance to disease activity.

Methods

A machine learning approach was used to develop a model that can identify patients without disease progression. SSc patients included in the prospective Leiden SSc cohort and fulfilling the ACR/EULAR 2013 criteria were included. Disease progression was defined as progression in ≥1 organ system, and/or start of immunosuppression or death. Using elastic-net-regularisation, and including 90 independent clinical variables (100% complete), we trained the model on 75% and validated it on 25% of the patients, optimising on negative predictive value (NPV) to minimise the likelihood of missing progression. Probability cutoffs were identified for low and high risk for disease progression by expert assessment.

Results

Of the 492 SSc patients (follow-up range: 2–10 years), disease progression during follow-up was observed in 52% (median time 4.9 years). Performance of the model in the test set showed an AUC-ROC of 0.66. Probability score cutoffs were defined: low risk for disease progression (<0.197, NPV:1.0; 29% of patients), intermediate risk (0.197–0.223, NPV:0.82; 27%) and high risk (>0.223, NPV:0.78; 44%). The relevant variables for the model were: previous use of cyclophosphamide or corticosteroids, start with immunosuppressive drugs, previous gastrointestinal progression, previous cardiovascular event, pulmonary arterial hypertension, modified Rodnan Skin Score, creatine kinase and diffusing capacity for carbon monoxide.

Conclusion

Our machine-learning-assisted model for progression enabled us to classify 29% of SSc patients as ‘low risk’. In this group, annual assessment programmes could be less extensive than indicated by international guidelines.

Cannabinoids for skin diseases and hair regrowth

The use of cannabis for skin diseases and hair regrowth is at the preliminary stage.

LEGALIZATION

Many countries have approved cannabis for medical use; however, four countries Canada, Uruguay, South Africa, and Georgia have legalized it for both medical and recreational purposes.

THE ENDOCANNABINOID SYSTEM

The endocannabinoid system may maintain skin homeostasis; two notable endocannabinoids include 2-Arachidonoylglycerol (2-AG) and N-arachidonoylethanolamine (AEA).

ROUTES OF ADMINISTRATION AND PHARMACOKINETICS

Topical cannabinoids can avoid the first-pass metabolism and reduce respiratory side effects; however, the high hydrophobicity of cannabinoids may hinder percutaneous absorption.

SKIN DISORDERS AND HAIR GROWTH

Human clinical studies suggest that cannabinoids may be used in eczema, acne, pruritus, and systemic sclerosis treatment. Cannabidiol (CBD) may enhance hair growth via multiple mechanisms.

SAFETY

Topical cannabis may cause mild side effects such as pruritus, burning, erythema, and stinging; they are relatively safer than inhalation and oral cannabis. Cannabis use may be associated with allergic symptoms and reduced immune response to live vaccination.

CANNABINOIDS IN PRACTICE

Despite growing interest, dermatologists should be cautious prescribing cannabinoids due to insufficient clinical data on both efficacy and safety.

New Insights into Profibrotic Myofibroblast Formation in Systemic Sclerosis: When the Vascular Wall Becomes the Enemy

In systemic sclerosis (SSc), abnormalities in microvessel morphology occur early and evolve into a distinctive vasculopathy that relentlessly advances in parallel with the development of tissue fibrosis orchestrated by myofibroblasts in nearly all affected organs. Our knowledge of the cellular and molecular mechanisms underlying such a unique relationship between SSc-related vasculopathy and fibrosis has profoundly changed over the last few years. Indeed, increasing evidence has suggested that endothelial-to-mesenchymal transition (EndoMT), a process in which profibrotic myofibroblasts originate from endothelial cells, may take center stage in SSc pathogenesis. While in arterioles and small arteries EndoMT may lead to the accumulation of myofibroblasts within the vessel wall and development of fibroproliferative vascular lesions, in capillary vessels it may instead result in vascular destruction and formation of myofibroblasts that migrate into the perivascular space with consequent tissue fibrosis and microvessel rarefaction, which are hallmarks of SSc. Besides endothelial cells, other vascular wall-resident cells, such as pericytes and vascular smooth muscle cells, may acquire a myofibroblast-like synthetic phenotype contributing to both SSc-related vascular dysfunction and fibrosis. A deeper understanding of the mechanisms underlying the differentiation of myofibroblasts inside the vessel wall provides the rationale for novel targeted therapeutic strategies for the treatment of SSc.

A Physiologically Based Pharmacokinetic and Drug-Drug Interaction Model for the CB2 Agonist Lenabasum

BACKGROUND AND OBJECTIVES

Lenabasum is a synthetic agonist of the cannabinoid receptor type 2 (CB2) with anti-inflammatory and antifibrotic properties. Utilizing Simcyp, we developed a physiologically based pharmacokinetic (PBPK) model based on physicochemical properties, cell culture data, and cytochrome P450 (CYP) phenotyping, inhibition, and induction data.

METHODS

Clinical data from healthy volunteers treated with 20 mg of lenabasum in a single ascending dose (SAD) study were used for model development. The model was verified using lenabasum SAD (10 and 40 mg) data as well as multiple dose (20 mg three times per day) data. Lenabasum is a CYP substrate, and the model predicted lenabasum clearance of 51% by CYP2C9, 37% by CYP2C8, and 12% by CYP3A4. Lenabasum is also an inhibitor of these isozymes.

RESULTS

The model accurately described the area under the plasma concentration-time curve (AUC) and maximum plasma concentration (C_max) for lenabasum within 1.19-fold and 1.25-fold accuracy, respectively, of the observed clinical values. The simulations of CYP inducers predicted that the strongest interaction would occur with rifampin, with the AUC decreasing to 0.36 of the control value, whereas the simulations of CYP inhibitors predicted that the greatest effect would occur with fluconazole, with a 1.43-fold increase in AUC.

CONCLUSIONS

Our model is a useful tool for predicting the pharmacokinetics of lenabasum and adjustments to its dosing in possible drug-drug interaction scenarios.

National Institutes of Health Consensus Development Project on Criteria for Clinical Trials in Chronic Graft-versus-Host Disease: IV. The 2020 Highly morbid forms report

Chronic graft-versus-host disease (GVHD) can be associated with significant morbidity, in part because of nonreversible fibrosis, which impacts physical functioning (eye, skin, lung manifestations) and mortality (lung, gastrointestinal manifestations). Progress in preventing severe morbidity and mortality associated with chronic GVHD is limited by a complex and incompletely understood disease biology and a lack of prognostic biomarkers. Likewise, treatment advances for highly morbid manifestations remain hindered by the absence of effective organ-specific approaches targeting "irreversible" fibrotic sequelae and difficulties in conducting clinical trials in a heterogeneous disease with small patient numbers. The purpose of this document is to identify current gaps, to outline a roadmap of research goals for highly morbid forms of chronic GVHD including advanced skin sclerosis, fasciitis, lung, ocular and gastrointestinal involvement, and to propose strategies for effective trial design. The working group made the following recommendations: (1) Phenotype chronic GVHD clinically and biologically in future cohorts, to describe the incidence, prognostic factors, mechanisms of organ damage, and clinical evolution of highly morbid conditions including long-term effects in children; (2) Conduct longitudinal multicenter studies with common definitions and research sample collections; (3) Develop new approaches for early identification and treatment of highly morbid forms of chronic GVHD, especially biologically targeted treatments, with a special focus on fibrotic changes; and (4) Establish primary endpoints for clinical trials addressing each highly morbid manifestation in relationship to the time point of intervention (early versus late). Alternative endpoints, such as lack of progression and improvement in physical functioning or quality of life, may be suitable for clinical trials in patients with highly morbid manifestations. Finally, new approaches for objective response assessment and exploration of novel trial designs for small populations are required.

An update on targeted therapies in systemic sclerosis based on a systematic review from the last 3 years

New molecular mechanisms that can be targeted with specific drugs have recently emerged for the treatment of systemic sclerosis (SSc) patients. Over the past 3 years, the achievement of one large phase 3 trial has led to the approval by drug agencies of the first drug licenced for SSc-related interstitial lung disease. Given this exciting time in the SSc field, we aimed to perform a systemic literature review of phase 1, phase 2 and phase 3 clinical trials and large observational studies about targeted therapies in SSc. We searched MEDLINE/PubMed, EMBASE, and ClinicalTrials.gov for clinical studies from 2016 with targeted therapies as the primary treatment in patients with SSc for skin or lung involvement as the primary clinical outcome measure. Details on the study characteristics, the trial drug used, the molecular target engaged by the trial drug, the inclusion criteria of the study, the treatment dose, the possibility of concomitant immunosuppression, the endpoints of the study, the duration of the study and the results obtained were reviewed. Of the 973 references identified, 21 (4 conference abstracts and 17 articles) were included in the systematic review. A total of 15 phase 1/phase 2 clinical trials, 2 phase 3 clinical trials and 2 observation studies were analysed. The drugs studied in phase 1/phase 2 studies included the following: inebilizumab, dabigatran, C-82, pomalidomide, rilonacept, romilkimab, tocilizumab, tofacitinib, pirfenidone, lenabasum, abatacept, belimumab, riociguat, SAR100842 and lanifibranor. All but 3 studies were performed in early diffuse SSc patients with different inclusion criteria, while 3 studies were performed in SSc patients with interstitial lung disease (ILD). Phase 3 clinical trials investigated nintedanib and tocilizumab. Nintedanib was investigated in SSc-ILD patients whereas tocilizumab focused on early diffuse SSc patients with inflammatory features. Two observational studies including > 50 patients with rituximab as the targeted drug were also evaluated. All these studies offer a real hope for SSc patients. The future challenges will be to customize patient-specific therapeutics with the goal to develop precision medicine for SSc.