Pharmacotherapy for osteoarthritis-related pain: current and emerging therapies

INTRODUCTION

Osteoarthritis (OA) related pain has affected millions of people worldwide. However, the current pharmacological options for managing OA-related pain have not achieved a satisfactory effect.

AREAS COVERED

This narrative review provides an overview of the current and emerging drugs for OA-related pain. It covers the drugs' mechanism of action, safety, efficacy, and limitations. The National Library of Medicine (PubMed) database was primarily searched from 2000 to 2024.

EXPERT OPINION

Current treatment options are limited and suboptimal for OA pain management. Topical nonsteroidal anti-inflammatory drugs (NSAIDs) are the recognized and first-line treatment in the management of OA-related pain, and other drugs are inconsistent recommendations by guidelines. Emerging treatment options are promising for OA-related pain, including nerve growth factor (NGF) inhibitors, ion channel inhibitors, and calcitonin gene-related peptide (CGRP) antagonists. Besides, drugs repurposing from antidepressants and antiepileptic analgesics are shedding light on the management of OA-related pain. The management of OA-related pain is challenging as pain is heterogeneous and subjective. A more comprehensive strategy combined with non-pharmacological therapy needs to be considered, and tailored management options to individualized patients.

Cyaonoside A-loaded composite hydrogel microspheres to treat osteoarthritis by relieving chondrocyte inflammation

Cyaonoside A (CyA), derived from the natural Chinese medicine, Cyathula officinalis Kuan, which was for a long time used to treat knee injuries and relieve joint pain in traditional Chinese medicine, showed an unclear mechanism for protecting cartilage. In addition, CyA was poorly hydrosoluble and incapable of being injected directly into the joint cavity, which limited its clinical application. This study reveals that CyA resisted IL-1β-mediated chondrogenic inflammation and apoptosis. Next, transcriptome sequencing is used to explore the potential mechanisms underlying CyA regulation of MSC chondrogenic differentiation. Based on these findings, CyA-loaded composite hydrogel microspheres (HLC) were developed and they possessed satisfactory loading efficiency, a suitable degradation rate and good biocompatibility. HLC increased chondrogenic anabolic gene (Acan, COL2A, and SOX9) expression, while downregulating the expression of the catabolic marker MMP13 in vitro. In the osteoarthritis mouse model, HLC demonstrated promising therapeutic capabilities by protecting the integrity of articular cartilage. In conclusion, this study provides insights into the regulatory mechanisms of CyA for chondrocytes and proposes a composite hydrogel microsphere-based advanced therapeutic strategy for osteoarthritis.

Near Infrared Responsive Gold Nanorods Attenuate Osteoarthritis Progression by Targeting TRPV1

Osteoarthritis (OA) is the most common degenerative joint disease worldwide, with the main pathological manifestation of articular cartilage degeneration. It have been investigated that pharmacological activation of transient receptor potential vanilloid 1 (TRPV1) significantly alleviated cartilage degeneration by abolishing chondrocyte ferroptosis. In this work, in view of the thermal activated feature of TRPV1, Citrate-stabilized gold nanorods (Cit-AuNRs) is conjugated to TRPV1 monoclonal antibody (Cit-AuNRs@Anti-TRPV1) as a photothermal switch for TRPV1 activation in chondrocytes under near infrared (NIR) irradiation. The conjugation of TRPV1 monoclonal antibody barely affect the morphology and physicochemical properties of Cit-AuNRs. Under NIR irradiation, Cit-AuNRs@Anti-TRPV1 exhibited good biocompatibility and flexible photothermal responsiveness. Intra-articular injection of Cit-AuNRs@Anti-TRPV1 followed by NIR irradiation significantly activated TRPV1 and attenuated cartilage degradation by suppressing chondrocytes ferroptosis. The osteophyte formation and subchondral bone sclerosis are remarkably alleviated by NIR-inspired Cit-AuNRs@Anti-TRPV1. Furthermore, the activation of TRPV1 by Cit-AuNRs@Anti-TRPV1 evidently improved physical activities and alleviated pain of destabilization of the medial meniscus (DMM)-induced OA mice. The study reveals Cit-AuNRs@Anti-TRPV1 under NIR irradiation protects chondrocytes from ferroptosis and attenuates OA progression, providing a potential therapeutic strategy for the treatment of OA.

Drug Delivery Strategies and Nanozyme Technologies to Overcome Limitations for Targeting Oxidative Stress in Osteoarthritis

Oxidative stress is an important, but elusive, therapeutic target for osteoarthritis (OA). Antioxidant strategies that target oxidative stress through the elimination of reactive oxygen species (ROS) have been widely evaluated for OA but are limited by the physiological characteristics of the joint. Current hallmarks in antioxidant treatment strategies include poor bioavailability, poor stability, and poor retention in the joint. For example, oral intake of exogenous antioxidants has limited access to the joint space, and intra-articular injections require frequent dosing to provide therapeutic effects. Advancements in ROS-scavenging nanomaterials, also known as nanozymes, leverage bioactive material properties to improve delivery and retention. Material properties of nanozymes can be tuned to overcome physiological barriers in the knee. However, the clinical application of these nanozymes is still limited, and studies to understand their utility in treating OA are still in their infancy. The objective of this review is to evaluate current antioxidant treatment strategies and the development of nanozymes as a potential alternative to conventional small molecules and enzymes.

Unraveling the role of natural functional oils in modulating osteoarthritis related complications

Osteoarthritis (OA) is a common joint disease and has been studied extensively in recent years as no promising therapy available so far for its treatment and remains a great challenge for health care specialists. Although the identification of some major mechanisms that contribute to this disease suggests a plethora of bioactive agents in tackling the associated complications yet OA's pathophysiology is still poorly understood owing to complex mechanistic changes observed. Experimental research is now exploring a wide range of therapeutically effective agents in an effort to find a way to repair OA-related joint degeneration and halt it from getting worse. Data was acquired and reviewed from most relevant and recent studies. This review summarizes the studies that are currently available and focuses on how various unconventional functional oils affect osteoarthritis and the affected joint tissues. An analysis of the recent scientific literature allowed us to highlight the potential anti-arthritic properties of edible oils and their main constituents, which seems to suggest an interesting new potential therapeutic application. Due to eccentric nature of OA, it is necessary to concentrate initially on the management of symptoms. The evidence supporting functional oils chondroprotective potential is still accumulating, underpinning a global need for more sustainable natural sources of treatment. More clinical research that focuses on the consequences of long-term treatment, possible negative effects, and epigenetic implications is necessary to get optimistic results. However, different animal or clinical studies suggest that linolenic and linoleic fatty acids decreased chondrocyte oxidative stress, cartilage breakdown, and expression of inflammatory markers. Distinct fatty acids along with minor components of oils also reduced the generation of prostaglandins and decreased oxidative stress. Furthermore, the potential roles of the main components of edible oils and possible negative results (if any) are also reported. While no severe side effects have been reported for any edible oils. Overall, these studies identify and support the use of functional oils as an adjuvant therapy for the management of OA and as a means of symptomatic alleviation for OA patients. However, to prove the effectiveness or to draw precise conclusions, high-quality clinical trials are required.

Piperine-loaded nanoparticles incorporated into hyaluronic acid/sodium alginate-based membranes for the treatment of inflammatory skin diseases

Piperine is an alkaloid mostly found in the fruits of several species of the Piper genus, and its anti-inflammatory potential is already known. However, its therapeutic applications still need to be better explored due to the low aqueous solubility of this active. To overcome this drawback, the objective of this work was to evaluate the efficiency of the nanoencapsulation of the compound as well as its incorporation into hyaluronic acid/alginate-based biomembranes. Polymeric nanoparticles composed of Eudragit S100 and Poloxamer 188 were obtained by the nanoprecipitation technique, obtaining spherical nanosized particles with an average diameter of 122.1 ± 2.0 nm, polydispersity index of 0.266, and encapsulation efficiency of 76.2 %. Hyaluronic acid/sodium alginate membranes were then prepared and characterized. Regarding permeation, a slow passage rate was observed until the initial 14 h, when an exponential increase in the recovered drug concentration began to occur. The in vivo assay showed a reduction in inflammation up to 43.6 %, and no cytotoxicity was observed. The results suggested the potential of the system developed for the treatment of inflammatory skin diseases.

Challenges in osteoarthritis treatment

Osteoarthritis (OA) is the most common form of arthritis and a degenerative joint cartilage disease that is the most common cause of disability in the world among the elderly. It leads to social, psychological, and economic costs with financial consequences. The principles of OA treatment are to reduce pain and stiffness as well as maintain function. In recent years, due to a better understanding of the underlying pathophysiology of OA, a number of potential therapeutic advances have been made, which include tissue engineering, immune system manipulation, surgical technique, pharmacological, and non-pharmacological treatments. Despite this, there is still no certain cure for OA, and different OA treatments are usually considered in relation to the stage of the disease. The purpose of the present review is to summarize and discuss the latest results of new treatments for OA and potential targets for future research.

Bardoxolone methyl ameliorates osteoarthritis by inhibiting osteoclastogenesis and protecting the extracellular matrix against degradation

Inflammation and oxidative damage are closely related to the development of osteoarthritis. Bardoxolone methyl (CDDO-Me), a semisynthetic oleanane triterpenoid, plays a strong anti-inflammatory and antioxidant role. The purpose of our research was to explore fundamental mechanisms of CDDO-Me in orthopaedics development. The results showed that CDDO-Me inhibited nuclear factor-κB ligand (RANKL)-induced osteoclast formation and extracellular matrix (ECM) degradation by activating the Nrf2/HO-1 signaling pathways and inhibiting NF-κB pathway activation and excess ROS production. In vivo, CDDO-Me significantly attenuated articular cartilage proteoglycan loss and the number of TRAP-positive osteoclasts in a destabilized medial meniscus (DMM) mouse model of OA. Taken together, these data demonstrate that CDDO-Me inhibits osteoclastogenesis and ECM degradation, underscoring its potential therapeutic value in treating OA.

Development of Nanomaterials to Target Articular Cartilage for Osteoarthritis Therapy

Osteoarthritis (OA) is an obstinate, degradative, and complicated disease that has drawn much attention worldwide. Characterized by its stubborn symptoms and various sequela, OA causes much financial burden on both patients and the health system. What’s more, conventional systematic therapy is not effective enough and causes multiple side effects. There’s much evidence that nanoparticles have unique properties such as high penetration, biostability, and large specific surface area. Thus, it is urgent to exploit novel medications for OA. Nanomaterials have been sufficiently studied, exploiting diverse nano-drug delivery systems (DDSs) and targeted nano therapeutical molecules. The nanomaterials are primarily intra-articular injected under the advantages of high topical concentration and low dosage. After administration, the DDS and targeted nano therapeutical molecules can specifically react with the components, including cartilage and synovium of a joint in OA, furthermore attenuate the chondrocyte apoptosis, matrix degradation, and macrophage recruitment. Thus, arthritis would be alleviated. The DDSs could load with conventional anti-inflammatory drugs, antibodies, RNA, and so on, targeting chondrocytes, synovium, or extracellular matrix (ECM) and releasing the molecules sequentially. The targeted nano therapeutical molecules could directly get to the targeted tissue, alleviating the inflammation and promoting tissue healing. This review will comprehensively collect and evaluate the targeted nanomaterials to articular cartilage in OA.

A Randomized Controlled Trial of Thai Medicinal Plant-4 Cream versus Diclofenac Gel in the Management of Symptomatic Osteoarthritis of the Knee

Background

Osteoarthritis of the knee is a common degenerative musculoskeletal condition. Thai Medicinal Plant-4 (TMP-4) cream is made up of Garcinia mangostana peel, Sesamum indicum seeds, Glycine max (L.) Merr. seeds, and Centella asiatica leaves, all of which have anti-inflammatory and analgesic properties. The present study aimed at determining the efficacy and safety of TMP-4 cream versus diclofenac gel in the treatment of symptomatic osteoarthritis of the knee.

Methods

A randomized-controlled trial was conducted to assess knee pain on a scale of 100 mm Visual Analog Scale (VAS) and other key metrics, including VAS knee stiffness, a modified 10-step stair climb test, a timed up and go test, the Knee Injury and Osteoarthritis Outcome Score, and safety outcomes, following administration of either TMP-4 cream or diclofenac gel for 4 weeks.

Results

A total of 199 patients with moderate knee pain intensity were randomly assigned to either TMP-4 cream or diclofenac gel (allocation ratio 1 : 1). The mean changes of VAS knee pain in the TMP-4 cream and diclofenac gel groups were −31.68 ± 14.18 mm and −31.09 ± 12.41 mm, respectively, (mean difference = −0.58, 95% confidence interval = −4.37–3.20, P=0.761). The upper limit of 95% confidence interval for the comparison between TMP-4 cream and diclofenac gel was within the predefined margin of 7 mm for noninferiority. The safety was comparable between the two interventions.

Conclusions

TMP-4 cream was noninferior to diclofenac gel in relieving osteoarthritic knee pain and may be considered as an alternative therapeutic option in the treatment of symptomatic osteoarthritis of the knee.

A systematic review of treatment for patients with burning mouth syndrome

BACKGROUND

Burning mouth syndrome is a chronic idiopathic intractable intraoral dysaesthesia that remains a challenge to clinicians due to its poorly understood pathogenesis and inconsistent response to various treatments.

AIM

This review aimed to study the short- (≤3 months) and long-term (>3 months) effectiveness and sustainable benefit of different burning mouth syndrome treatment strategies and the associated side effects.

MATERIALS AND METHODS

Randomised controlled trials of burning mouth syndrome treatment compared with placebo or other interventions with a minimum follow up of 2 months were searched from the PubMed, Embase and Cochrane database (published to July 2020).

RESULTS

Twenty-two studies were selected based on the inclusion and exclusion criteria and analysed. Nine categories of burning mouth syndrome treatment were identified: Anticonvulsant and antidepressant agents, phytomedicine and alpha lipoic acid supplements, low-level laser therapy, saliva substitute, transcranial magnetic stimulation, and cognitive behaviour therapy. Cognitive behaviour therapy, topical capsaicin and clonazepam, and laser therapy demonstrated favourable outcome in both short- and long-term assessment. Phytomedicines reported a short-term benefit in pain score reduction. The pooled effect of alpha lipoic acid (ALA) pain score improvement was low, but its positive effects increased in long term assessment.

CONCLUSION

A more significant volume in terms of sample size, multi-centres, and multi-arm comparison of therapeutic agents with placebo and longitudinal follow-up studies is recommended to establish a standardised burning mouth syndrome treatment protocol. Further studies are required to assess the analgesic benefits of topical clonazepam and capsaicin, alternative medicines with neurodegenerative prevention capability and psychology support in treating burning mouth syndrome and reducing systemic adverse drug reactions.Registration International Prospective Register of Systematic Reviews (PROSPERO):Protocol ID - CRD42020160892.

A Randomized Placebo-Controlled Trial of Efficacy and Safety: Drug-Free Gel Containing Ultra-Deformable Phospholipid Vesicles (TDT 064) in Osteoarthritic Knees

Background:

There are a number of topical agents that are used for treatment of knee osteoarthritis. Drug-free gels, containing ultra-deformable phospholipid vesicles (TDT 064) are one such topical therapy, which have been stated to act as a bio lubricant. However, the evidence of TDT 064 in treatment of knee osteoarthritis is limited. Hence, the aim of this study was to evaluate the efficacy of pain control as a primary outcome and safety of TDT 064 compared with a topical placebo.

Methods:

Sixty-four patients with primary osteoarthritis, with radiographic showing Kellgren and Lawrence classification grade II to III, were randomized into 2 groups. In the first group of 32 patients TDT 064 was used as topical agent, whilst in the second group of 32 patients a placebo identical in appearance was used instead. The verbal numerical rating scale (VNRS) was used for recording pain levels, Self-reported Knee Injury and Osteoarthritis Outcome Scores (KOOS) as well as amounts of rescue medication were also recorded. The data were recorded at the start of the study, and then at follow-up appointments of 14 days, 6 weeks, and 3 months.

Results:

The mean VNRS for pain in both groups were significantly improved, when compared to the start of treatment (P < .0001); however, there were no differences between groups at any follow up visit. KOOS in all subscales were not significantly different between both groups at baseline and at the end of treatment. However, the average amount of NSAIDs in the TDT 064 group was 26.39 ± 22.11 tabs, which was significantly lower than the control group; which used an average 37.03 ± 19.22 tabs in 3 months (P = .047).

Conclusions:

There were no differences in the VNRS for pain and KOOS scores between the active and placebo groups. Although, TDT 064 could decrease usage of rescue medication the difference with use of a placebo was minimal. Further, larger trials would also be beneficial to demonstrate any differences between TDT 064 and a placebo.

Trial Registration:

TCTR, TCTR 20190302001. Registered 1 March, 2019: http://www.clinicaltrials.in.th

Design, Preparation, and Characterization of Effective Dermal and Transdermal Lipid Nanoparticles: A Review

Limited permeability through the stratum corneum (SC) is a major obstacle for numerous skin care products. One promising approach is to use lipid nanoparticles as they not only facilitate penetration across skin but also avoid the drawbacks of conventional skin formulations. This review focuses on solid lipid nanoparticles (SLNs), nanostructured lipid nanocarriers (NLCs), and nanoemulsions (NEs) developed for topical and transdermal delivery of active compounds. A special emphasis in this review is placed on composition, preparation, modifications, structure and characterization, mechanism of penetration, and recent application of these nanoparticles. The presented data demonstrate the potential of these nanoparticles for dermal and transdermal delivery.

Xanthohumol Attenuated Inflammation and ECM Degradation by Mediating HO-1/C/EBPβ Pathway in Osteoarthritis Chondrocytes

Osteoarthritis (OA) is the most frequent and disabling disease in developed countries. The progressive degeneration of articular cartilage characterized as thinner and erosive. Inflammation is well-known to be involved in OA development. However, there are no effective therapeutic strategies to cure it. Xanthohumol (XH) is a natural prenylflavonoid isolated from hops and beer. The protective activity of XH against OA chondrocytes inflammation and ECM degradation is unclear. In this article, we found that XH significantly inhibited inflammatory responses, attenuated catabolic enzymes expression, and ameliorated ECM degradation, as showed by decreased production of NO, PGE2, TNFα, and IL-6, decreased expression of MMP-3/-13 and ADAMTS-4/-5, and increased expression of collagen-II and aggrecan. In addition, XH activated HO-1 signaling and attenuated IL-1β-induced C/EBPβ. XH promoted the interaction between HO-1 and C/EBPβ, inhibiting the nuclear translocation of C/EBPβ. HO-1 knockdown could abrogate the protective effects of XH in IL-1β-treated chondrocytes. Collectively, XH attenuated inflammatory responses and ECM degradation by mediating HO-1 and C/EBPβ signaling pathways in osteoarthritis chondrocytes.

Comprehensive Review of Knee Osteoarthritis Pharmacological Treatment and the Latest Professional Societies' Guidelines

Osteoarthritis is the most common musculoskeletal progressive disease, with the knee as the most commonly affected joint in the human body. While several new medications are still under research, many symptomatic therapy options, such as analgesics (opioid and non-opioid), nonsteroid anti-inflammatory drugs, symptomatic slow-acting drugs in osteoarthritis, and preparations for topical administration, are being used, with a diverse clinical response and inconsistent conclusions across various professional societies guidelines. The concept of pharmacogenomic-guided therapy, which lies on principles of the right medication for the right patient in the right dose at the right time, can significantly increase the patient’s response to symptom relief therapy in knee osteoarthritis. Corticosteroid intra-articular injections and hyaluronic acid injections provoke numerous discussions and disagreements among different guidelines, even though they are currently used in daily clinical practice. Biological options, such as platelet-rich plasma and mesenchymal stem cell injections, have shown good results in the treatment of osteoarthritis symptoms, greatly increasing the patient’s quality of life, especially when combined with other therapeutic options. Non-inclusion of the latter therapies in the guidelines, and their inconsistent stance on numerous therapy options, requires larger and well-designed studies to examine the true effects of these therapies and update the existing guidelines.

Comprehensive Review of Topical Analgesics for Chronic Pain

PURPOSE OF REVIEW

Topical analgesics are a non-opioid option for the treatment of chronic pain conditions including neuropathic pain, musculoskeletal pain, and osteoarthritis. There are many topical medications available; however their efficacy is variable. This article reviews the various topical analgesics, their mechanisms of action, and their efficacy.

RECENT FINDINGS

Studies have found topical NSAIDs are useful in treating acute musculoskeletal pain syndromes (strains and sprains) and show some efficacy in treating hand and knee osteoarthritis (Derry et al. Cochrane Database Syst Rev 5:CD008609, 2017). Topical capsaicin 8% has been shown to be efficacious in the treatment of postherpetic neuralgia, painful diabetic peripheral neuropathy, and HIV-neuropathy (Derry et al. Cochrane Database Syst Rev 1:CD007393, 2017). Topical lidocaine has been widely studied and found to reduce pain in patients with postherpetic neuralgia (Knezevic et al. Pain Manag 7:537-58, 2017). Although many other topical analgesics are available, there is limited data to support the efficacy of other agents. Topical analgesics are a relatively benign treatment for chronic pain conditions including neuropathic pain, musculoskeletal, and myofascial pain. There is evidence to support the use of topical NSAIDs, high concentration topical capsaicin, and topical lidocaine for various painful conditions.

Recent Advances in Clinical Translation of Intra-Articular Osteoarthritis Drug Delivery Systems

Osteoarthritis (OA) is a degenerative disease of the joints and a leading cause of physical disability in adults. Intra-articular (IA) therapy is a popular treatment strategy for localized, single-joint OA; however, small-molecule drugs such as corticosteroids do not provide prolonged relief. One possible reason for their lack of efficacy is high clearance rates from the joint through constant lymphatic drainage of the synovial tissues and synovial fluid and also by their exchange via the synovial vasculature. Advanced drug delivery strategies for extended release of therapeutic agents in the joint space is a promising approach to improve outcomes for OA patients. Broadly, the basic principle behind this strategy is to encapsulate therapeutic agents in a polymeric drug delivery system (DDS) for diffusion- and/or degradation-controlled release, whereby degradation can occur by hydrolysis or tied to relevant microenvironmental cues such as pH, reactive oxygen species (ROS), and protease activity. In this review, we highlight the development of clinically tested IA therapies for OA and highlight recent systems which have been investigated preclinically. DDS strategies including hydrogels, liposomes, polymeric microparticles (MPs) and nanoparticles (NPs), drug conjugates, and combination systems are introduced and evaluated for clinical translational potential.

Topical Delivery of Meloxicam using Liposome and Microemulsion Formulation Approaches

The aim of this study is to develop, characterize and compare conventional liposome, deformable liposome (transfersome) and microemulsion formulations as potential topical delivery systems for meloxicam. Liposomes were characterized in terms of vesicle size, zeta potential and entrapment efficiency. For microemulsions, particle size, electrical conductivity and viscosity studies were performed to assess the structure of the investigated systems. An ex vivo skin permeation study has been conducted to compare these formulations. The dermal and transdermal delivery of meloxicam using these formulations can be a promising alternative to conventional oral delivery of non-steroidal anti-inflammatory drugs (NSAIDs) with enhanced local and systemic onset of action and reduced side effects.

Phonophoretic application of a glucosamine and chondroitin nanoemulsion for treatment of knee chondropathies

Aim: This study was performed to assess the effect of the phonophoretic application of a nanoemulsion incorporating glucosamine and chondroitin sulfate (NANO-CG) associated with kinesiotherapy on the reduction of pain and stiffness in knee chondropathy. Materials & methods: NANO-CG was tested in vitro and in vivo prior to being applied in a randomized and controlled clinical trial. Results: Cell viability and hen's egg test-chorionallantonic membrane tests indicated the NANO-CG is safe for topical application. Permeation tests showed NANO-CG enhances drug permeation through the skin. There was no statistical significance between treated groups in this preliminary study, however, pain reduction and complete recovery of articular cartilage were observed in some patients treated with NANO-CG. Conclusion: We demonstrate that NANO-CG may be a promising candidate for the therapy of knee chondropathy.

Activation of Nrf2/HO-1 signal with Myricetin for attenuating ECM degradation in human chondrocytes and ameliorating the murine osteoarthritis

BACKGROUND

Osteoarthritis (OA), one of the prevailing joint degenerative disorders, contributes to the disability around the world. However, no effective therapeutic was introduced currently. Myricetin was reported to possess the function of anti-inflammatory, anti-diabetic and anti-cancer. Thus, we investigate the protection role of myricetin in OA progression and the potential molecular mechanism in present study.

METHODS

Quantitative realtime PCR and western blotting were performed to evaluate the expression of MMP-13, Aggrecan, iNOS, and COX-2 at both gene and protein levels. An enzyme-linked immunosorbent assay was used to evaluate the levels of inflammatory factors (PGE2, TNF-α, and IL-6). The PI3K/AKT, Nrf2/HO-1 and nuclear factor kappa B (NF-κB) signaling pathways were analyzed by western blotting, and immunofluorescence was used to assess the expression of Nrf2, Collagen II and MMP13. The in vitro effect of myricetin was evaluated by intragastric administration into a mouse osteoarthritis model induced by destabilization of the medial meniscus.

RESULTS

Myricetin not only inhibited the generation of inflammatory mediators and cytokines such as nitric oxide (NO), prostaglandin E2 (PGE2), TNF-α and IL-6, but also suppressed the production of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in human chondrocytes under IL-1β stimulation. Moreover, Metalloproteinase 13 (MMP13) and thrombospondin motifs 5 (ADAMTS5), which resulted in the degradation of cartilage, were also suppressed in chondrocytes with the treatment of myricetin. To explore the potential mechanism, we found out that myricetin suppressed NF-κB signaling pathway through Nrf2/HO-1 axis in human chondrocytes. Besides, myricetin regulated the Nrf2 signaling pathway through PI3K/Akt pathway. In addition, in vivo study demonstrated that myricetin could ameliorated the progression of OA in mice DMM model through PI3K/Akt mediated Nrf2 signaling pathway.

CONCLUSION

Taken together, our data first demonstrated that myricetin possesses the therapeutic potential on OA through PI3K/Akt mediated Nrf2/HO-1 signaling pathway.

Rationale and evidence for the incorporation of heparin into the diclofenac epolamine medicated plaster

OBJECTIVE

The nonsteroidal anti-inflammatory drug (NSAID) diclofenac epolamine (DHEP) formulated as a topical patch has demonstrated efficacy and safety in the localized treatment of acute pain from minor strains, sprains and contusions, and for epicondylitis and knee osteoarthritis. The glycosaminoglycan heparin enhances the activity of topical NSAIDs formulated as a medicated plaster, even in the absence of any significant release of heparin. Therefore, DHEP plus, a new formulation of the DHEP medicated plaster containing a small amount of heparin sodium as excipient, has been developed.

METHODS

We reviewed the pivotal and supportive studies of the clinical development program of the new patch and evaluated the role of heparin as an enhancer in the treatment of localized pain/inflammation of musculoskeletal structures, associated with post-traumatic and/or rheumatic conditions.

RESULTS

The data was consistent with the concept that heparin increased the clinical activity of the DHEP plus medicated plaster versus the reference DHEP medicated plaster through improved bioavailability due to enhanced movement of diclofenac from the plaster. Both DHEP formulations have the same dissolution profile, indicating that heparin does not change the physical and chemical characteristics of the plaster. Permeation testing showed that heparin is not released from the DHEP plus medicated plaster. Efficacy studies showed that the DHEP plus medicated plaster was significantly more effective in reducing pain than the reference marketed DHEP medicated plaster.

CONCLUSIONS

The benefit/risk assessment of DHEP plus 180 mg medicated plaster is favorable, with a safety profile equal to placebo and improved efficacy over the reference marketed DHEP medicated plaster.

The relative efficacy of topical non-steroidal anti-inflammatory drugs and capsaicin in osteoarthritis: a network meta-analysis of randomised controlled trials

OBJECTIVE

To compare the efficacy of topical non-steroidal anti-inflammatory drugs (NSAIDs) with topical capsaicin for pain relief in osteoarthritis (OA).

DESIGN

A systematic literature search was conducted for randomised controlled trials (RCTs) examining any topical NSAID or capsaicin in OA. Pain relief at or nearest to 4 weeks was pooled using a random-effects network meta-analysis (NMA) in a Frequentist and Bayesian setting. Analysis was conducted for all trials and for trials using drugs listed as licensed for OA in the British National Formulary (BNF).

RESULTS

The trial network comprised 28 RCTs (7372 participants), of which 17 RCTs (3174 participants) were included in the as licensed analyses. No RCTs directly compared topical NSAIDs with capsaicin. Placebo was the only common comparator for topical NSAIDs and capsaicin. Frequentist and Bayesian effect size (ES) estimates were in agreement. Topical NSAIDs were statistically superior to placebo overall (ES 0.30, 95% confidence interval [CI] 0.19 to 0.41) and as licensed (ES 0.32, 95% CI 0.24 to 0.39). However, capsaicin was only statistically superior to placebo when used at licensed doses (ES 0.41, 95% CI 0.17 to 0.64). No significant differences were observed in pain relief between topical NSAIDs and capsaicin (overall: ES 0.04, 95% CI -0.26 to 0.33; as licensed: ES-0.09, 95% CI -0.34 to 0.16).

CONCLUSIONS

Current evidence indicates that topical NSAIDs and capsaicin in licensed doses may be equally effective for pain relief in OA. Whether the equivalence varies between individuals remains unknown.

Topical therapies for knee osteoarthritis

BACKGROUND

Symptomatic knee osteoarthritis (OA) involves millions of adults around the world.

PURPOSE

To analyze the effectiveness and tolerability of topical therapies and their contemporary placement in knee OA management criteria.

METHODS

A Cochrane Library and PubMed (MEDLINE) search related to the role of topical therapies in knee OA was carried out.

RESULTS

Many types of local therapy have been reported, including nonsteroidal anti-inflammatory drugs (NSAIDs) like diclofenac and ketoprofen; capsaicin, cream containing glucosamine sulfate, chondroitin sulfate, and camphor; nimesulide; civamide cream 0.075%; menthol; drug-free gel containing ultra-deformable phospholipid vesicles (TDT 064); 4Jointz utilizing Acteev technology; herbal therapies; gel of medical leech (Hirudo medicinalis) saliva extract; and gel prepared using Lake Urmia mud. One systematic review showed that topical diclofenac and topical ketoprofen can alleviate pain. However, another systematic review found that topical diclofenac and ketoprofen had limited efficacy in knee OA at 6 to 12 weeks. Many studies with a low level of evidence have reported some pain mitigation using the rest of aforementioned topical therapies.

CONCLUSIONS

Although some controversy exists on the role of topical NSAIDs, current management guidelines advise topical NSAIDs as an option and even first-line therapy for knee OA treatment, particularly among elderly patients. Topical NSAIDs may be contemplated as similar options to oral NSAIDs and are associated with fewer gastrointestinal complications when compared with oral NSAIDs. Caution should be taken with the use of both topical and oral NSAIDs, including close adherence to dosing regimens and monitoring, especially for patients with previous complications of NSAIDs. The role of other topical therapies needs further research.

Fabrication of Tip-Dissolving Microneedles for Transdermal Drug Delivery of Meloxicam

Dissolving microneedles (MNs) offered a simple, minimally invasive method for meloxicam (MX) delivery to the skin. However, the fabrication of dissolving MNs still faced some challenges, such as significant time consumption, loss of drug activity, and difficulty in regulating MN drug loading. To address these issues, we developed the tip-dissolving (TD) MNs. Several kinds of drugs were encapsulated successfully, and the quantity of MX ranged from 37.23 ± 8.40 to 332.53 ± 13.37 μg was precisely controlled. The effects of fabrication process on biomacromolecules stability were studied, and it was found that tyrosinase kept 90.4% activity during the fabrication process. The whole process for the fabrication of MNs only takes approximately 1 h. In order to further evaluate the potential of the TD MNs, MX TD MNs were prepared for in vitro release experiments, in vivo release experiments, safety evaluation, pharmacokinetic studies, and pharmacodynamic studies. The results demonstrated that MX TD MNs offered several advantages, including rapid release of the encapsulated drug (91.72% within 30 min), efficient drug delivery to skin (79.18%), no obvious skin irritation, decent relative bioavailability (122.3%), and strong anti-inflammatory and analgesic effects. Based on these results, we envisage that the TD MNs have promising potential for transdermal drug delivery of MX.

Consensus recommendations for managing osteoarthritic pain with topical NSAIDs in Asia-Pacific

Osteoarthritis prevalence is expected to increase markedly in the Asia-Pacific region due to rapid population aging. Identifying effective and safe therapeutic options to manage osteoarthritic pain is viewed as a priority. The Asia-Pacific Experts on Topical Analgesics Advisory Board developed consensus statements for use of topical NSAIDs in musculoskeletal pain. Evidence supporting these statements in osteoarthritic pain was reviewed. Best available evidence indicates that topical NSAIDs have a moderate effect on relief of osteoarthritic pain, comparable to that of oral NSAIDs but with a better risk-to-benefit ratio. International clinical practice guidelines recommend topical NSAIDs on par with or ahead of oral NSAIDs for pain management in patients with knee and hand osteoarthritis, and as the first-line choice in persons aged ≥75 years.

Representative literature on the phytonutrients category: Phenolic acids

Research concerning the benefits derived from dietary polyphenols, a significant class within the family of phytonutrients, has increased considerably in the last decade. Prior to the late 1990s, the nutritional spotlight focused on the antioxidant capabilities of carotenoids, vitamins, and minerals. More recently, however, research has emerged in strong support of the antioxidant capacity of polyphenols and their role in the prevention and/or treatment of certain cancers, diabetes, cardiovascular diseases, and inflammation. Polyphenols are categorized according to the nature of their carbon skeleton, ranging from basic phenolic molecules to highly complex compounds, such as flavonoids, the most common and widely studied of all phenolic compounds. The most prevalent phenolic acids include ellagic acid, gallic acid, tannic acid, and capsaicin.

Increased permeability of reconstructed human epidermis from UVB-irradiated keratinocytes

Extrinsic (photo) aging accelerates chronologically aging in the skin due to cumulative UV irradiation. Despite recent insights into the molecular mechanisms of fibroblast aging, age-related changes of the skin barrier function have been understudied. In contrast, the constantly increasing subpopulation of aged patients causes a clinical need for effective and safe (dermatological) treatment. Herein, we reconstructed human epidermis from UVB-irradiated keratinocytes (UVB-RHE). UVB-irradiated keratinocytes show higher activity of senescence associated β-galactosidase, less cell proliferation, and reduced viability. Higher amounts of β-galactosidase are also detectable in UVB-RHE. Moreover, UVB-RHE release more interleukin-1α and -8 into the culture medium and present altered differentiation with a thinner stratum corneum compared to normal RHE. For the first time, the permeation of testosterone and caffeine through UVB-irradiated RHE indicate a clear influence of the UVB stress on the skin barrier function. Impaired barrier function was confirmed by the increased permeation of testosterone and caffeine as well as by the increased penetration of dendritic core-multishell nanocarriers into the constructs. Taken together, UVB-RHE emulate hallmarks of skin aging and might contribute to an improved non-clinical development of medicinal or cosmetic products.

Capsaicin, Nociception and Pain

Capsaicin, the pungent ingredient of the hot chili pepper, is known to act on the transient receptor potential cation channel vanilloid subfamily member 1 (TRPV1). TRPV1 is involved in somatic and visceral peripheral inflammation, in the modulation of nociceptive inputs to spinal cord and brain stem centers, as well as the integration of diverse painful stimuli. In this review, we first describe the chemical and pharmacological properties of capsaicin and its derivatives in relation to their analgesic properties. We then consider the biochemical and functional characteristics of TRPV1, focusing on its distribution and biological effects within the somatosensory and viscerosensory nociceptive systems. Finally, we discuss the use of capsaicin as an agonist of TRPV1 to model acute inflammation in slices and other ex vivo preparations.

Nanofibers used for the delivery of analgesics

Nanofibers are extremely advantageous for drug delivery because of their high surface area-to-volume ratios, high porosities and 3D open porous structures. Local delivery of analgesics by using nanofibers allows site-specificity and requires a lower overall drug dosage with lower adverse side effects. Different analgesics have been loaded onto various nanofibers, including those that are natural, synthetic and copolymer, for various medical applications. Analgesics can also be singly or coaxially loaded onto nanofibers to enhance clinical applications. In particular, analgesic-eluting nanofibers provide additional benefits to preventing wound adhesion and scar formation. This paper reviews current research and breakthrough discoveries on the innovative application of analgesic-loaded nanofibers that will alter the clinical therapy of pain.

Topical NSAIDs for chronic musculoskeletal pain in adults

BACKGROUND

Use of topical nonsteroidal anti-inflammatory drugs (NSAIDs) to treat chronic musculoskeletal conditions has become widely accepted because they can provide pain relief without associated systemic adverse events. This review is an update of 'Topical NSAIDs for chronic musculoskeletal pain in adults', originally published in Issue 9, 2012.

OBJECTIVES

To review the evidence from randomised, double-blind, controlled trials on the efficacy and safety of topically applied NSAIDs for chronic musculoskeletal pain in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and our own in-house database; the date of the last search was February 2016. We also searched the references lists of included studies and reviews, and sought unpublished studies by asking personal contacts and searching online clinical trial registers and manufacturers' web sites.

SELECTION CRITERIA

We included randomised, double-blind, active or inert carrier (placebo) controlled trials in which treatments were administered to adults with chronic musculoskeletal pain of moderate or severe intensity. Studies had to meet stringent quality criteria and there had to be at least 10 participants in each treatment arm, with application of treatment at least once daily.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. We used numbers of participants achieving each outcome to calculate risk ratio and numbers needed to treat (NNT) or harm (NNH) compared to carrier or other active treatment. We were particularly interested to compare different formulations (gel, cream, plaster) of individual NSAIDs. The primary outcome was 'clinical success', defined as at least a 50% reduction in pain, or an equivalent measure such as a 'very good' or 'excellent' global assessment of treatment, or 'none' or 'slight' pain on rest or movement, measured on a categorical scale.

MAIN RESULTS

We identified five new studies for this update, which now has information from 10,631 participants in 39 studies, a 38% increase in participants from the earlier review; 33 studies compared a topical NSAID with carrier. All studies examined topical NSAIDs for treatment of osteoarthritis, and for pooled analyses studies were generally of moderate or high methodological quality, although we considered some at risk of bias from short duration and small size.In studies lasting 6 to 12 weeks, topical diclofenac and topical ketoprofen were significantly more effective than carrier for reducing pain; about 60% of participants had much reduced pain. With topical diclofenac, the NNT for clinical success in six trials (2343 participants) was 9.8 (95% confidence interval (CI) 7.1 to 16) (moderate quality evidence). With topical ketoprofen, the NNT for clinical success in four trials (2573 participants) was 6.9 (5.4 to 9.3) (moderate quality evidence). There was too little information for analysis of other individual topical NSAIDs compared with carrier. Few trials compared a topical NSAID to an oral NSAID, but overall they showed similar efficacy (low quality evidence). These efficacy results were almost completely derived from people with knee osteoarthritis.There was an increase in local adverse events (mostly mild skin reactions) with topical diclofenac compared with carrier or oral NSAIDs, but no increase with topical ketoprofen (moderate quality evidence). Reporting of systemic adverse events (such as gastrointestinal upsets) was poor, but where reported there was no difference between topical NSAID and carrier (very low quality evidence). Serious adverse events were infrequent and not different between topical NSAID and carrier (very low quality evidence).Clinical success with carrier occurred commonly - in around half the participants in studies lasting 6 to 12 weeks. Both direct and indirect comparison of clinical success with oral placebo indicates that response rates with carrier (topical placebo) are about twice those seen with oral placebo.A substantial amount of data from completed, unpublished studies was unavailable (up to 6000 participants). To the best of our knowledge, much of this probably relates to formulations that have never been marketed.

AUTHORS' CONCLUSIONS

Topical diclofenac and topical ketoprofen can provide good levels of pain relief beyond carrier in osteoarthritis for a minority of people, but there is no evidence for other chronic painful conditions. There is emerging evidence that at least some of the substantial placebo effects seen in longer duration studies derive from effects imparted by the NSAID carrier itself, and that NSAIDs add to that.

Efficacy and safety of diclofenac sodium 2% topical solution for osteoarthritis of the knee: a randomized, double-blind, vehicle-controlled, 4 week study

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) are standard therapy for osteoarthritis (OA). Topically applied NSAIDs reduce systemic exposure compared with oral NSAIDS, and European guidelines recommend their use. The NSAID diclofenac is available in a range of topical formulations. Diclofenac 1% gel and 1.5% four times daily and 2% twice daily (BID) solutions are approved to reduce pain from OA of the knee(s). The objective of this study was to investigate the efficacy and safety of diclofenac sodium 2% topical solution BID versus vehicle control solution for treating pain associated with OA of the knee.

RESEARCH DESIGN AND METHODS

A phase II, 4 week, randomized, double-blind, parallel-group, two-arm, vehicle-controlled study compared pain relief with diclofenac sodium 2% topical solution versus control (vehicle only) in patients aged 40 to 85 years with radiographically confirmed primary OA of the knee.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT01119898.

MAIN OUTCOME MEASURES

The primary efficacy outcome was change from baseline to the final visit in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale. Secondary outcomes included additional WOMAC subscales and patient global assessment of OA. Treatment-emergent adverse events (TEAEs), skin irritation, and vital signs were assessed and collected throughout the study.

RESULTS

Of 260 patients randomized, 259 received ≥1 dose of study drug. Significantly greater reductions in least-squares mean (standard error) WOMAC pain scores were observed for diclofenac-treated (-4.4 [0.4]) versus vehicle-treated patients (-3.4 [0.4]) at the final visit (p = 0.040). The most commonly reported TEAEs were administration site conditions. The vehicle-treated group experienced slightly more TEAEs than the active treatment group (38.8% vs. 31.5%). No serious adverse events were reported.

CONCLUSIONS

Administration of diclofenac sodium 2% topical solution BID resulted in significantly greater improvement in pain reduction in patients with OA of the knee versus vehicle control and was generally well tolerated.

Efficacy and safety of topical NSAIDs in the management of osteoarthritis: Evidence from real-life setting trials and surveys

Topical non-steroidal anti-inflammatory drugs (NSAIDs) are recommended in international and national guidelines as an early treatment option for the symptomatic management of knee and hand osteoarthritis (OA), and may be used ahead of oral NSAIDs due to their superior safety profile. The European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO) treatment algorithm recommends topical NSAIDs for knee OA in addition to the pharmacological background of symptomatic slow-acting drugs for osteoarthritis (SYSADOAs) and rescue analgesia with paracetamol and non-pharmacological treatment, if the patient is still symptomatic. Topical NSAIDs have a moderate effect on pain relief, with efficacy similar to that of oral NSAIDs, with the advantage of a better risk:benefit ratio. In real-life studies, topical and oral NSAIDs demonstrate an equivalent effect on knee pain over 1 year of treatment, with fewer adverse events due to lower systemic absorption of topical NSAIDs compared with oral NSAIDs. As a result, topical NSAIDs may be the preferred treatment option, especially in OA patients aged ≥75 years, and those with co-morbidities or at an increased risk of cardiovascular, gastrointestinal, or renal side effects. Furthermore, using topical NSAIDs in inflammatory rheumatic diseases leads to a 40% reduction in the need for concomitant oral NSAIDs. When selecting a topical NSAID, absorption and bioavailability are important because of heterogeneity among topical drug formulations. Molecules like etofenamate have a bioavailability of >20% and evidence for accumulation in synovial tissues, with efficacy demonstrated as improvement in pain and function in real-life studies of OA patients. Diclofenac also shows good efficacy alongside evidence that diclofenac accumulates in the synovium.

A Mechanism-Based Approach to the Management of Osteoarthritis Pain

Pain from osteoarthritis (OA) affects millions of people worldwide, yet treatments are limited to acetaminophen, NSAIDs, physical therapy, and ultimately, surgery when there is significant disability. In recent years, our understanding of pain pathways in OA has developed considerably. Though joint damage and inflammation play a significant role in pain generation, it is now understood that both central and peripheral nervous system mechanisms exacerbate symptoms. Evolving management strategies for OA address central factors (e.g., sleep difficulties, catastrophizing, and depression) with treatments such as cognitive behavioral therapy and exercise. In addition, emerging data suggest that antibodies against peripheral signaling neuropeptides, such as nerve growth factor-1 (NGF-1), may significantly alleviate pain. However, concerns regarding potential adverse effects, such as rapidly progressive OA, still remain. A nuanced understanding is essential if we are to make headway in developing more effective treatments for OA.

[Osteoarthritis: what internists should know]

Osteoarthritis is the most frequent joint disorder and substantially affects patient quality of life. As an age-related disease it leads to an increasing financial burden for the healthcare system due to the current demographic changes. Osteoarthritis affects every single tissue in the joint. The identification of the source of disease symptoms is the key to a successful management. Therapeutic approaches include non-pharmacological and pharmacological treatment. Surgery is the therapeutic end stage (e.g. total joint replacement, high tibial osteotomy and arthrodesis). This overview focuses on the pharmacological treatment whereas the clinical manifestations and non-pharmacological approaches are only briefly dealt with.

Clinical trial data in support of changing guidelines in osteoarthritis treatment

Goals for the management of osteoarthritis (OA) emphasize pain relief, reduction of inflammation, and improvement in functioning. Among pharmacological pain management interventions, nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently recommended as the most effective treatment option for OA. However, the use of traditional oral NSAIDs is associated with risk of serious adverse events involving the gastrointestinal, cardiovascular, and renal systems. Topical NSAIDs are an alternative with well-established tolerability and efficacy in the treatment of OA of the knee or hand. While the management of OA pain is evolving toward the more widespread use of topical NSAIDs, some OA management guidelines have yet to incorporate these agents in their recommendations. This review examines the efficacy and tolerability of topical NSAIDs, their current placement in OA management guidelines, and their potential role in enabling pain specialists to provide individualized care for their patients with OA.

Evolving guidelines in the use of topical nonsteroidal anti-inflammatory drugs in the treatment of osteoarthritis

Background

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a standard treatment for osteoarthritis (OA), but the use of oral NSAIDs has been linked to an elevated risk for cardiovascular and gastrointestinal adverse events and renal toxicity. Topical NSAIDs are thought to afford efficacy that is comparable to oral formulations while reducing widespread systemic drug exposure, which may provide a benefit in terms of safety and tolerability. As a result, European treatment guidelines have, for many years, recommended the use of topical NSAIDs as a safe and effective treatment option for OA. Following the recent approval of several topical NSAID formulations by the US Food and Drug Administration, US treatment guidelines are increasingly recommending the use of topical NSAIDs as an alternative therapy and, in some cases, as a first-line option for OA. This commentary summarizes OA treatment guidelines that are currently available and discusses their potential evolution with regard to the increased inclusion of topical NSAIDs.

Knee osteoarthritis related pain: a narrative review of diagnosis and treatment

BACKGROUND

Osteoarthritis is a common progressive joint disease, involving not only the joint lining but also cartilage, ligaments, and bone. For the last ten years, majority of published review articles were not specific to osteoarthritis of the knee, and strength of evidence and clinical guidelines were not appropriately summarized.

OBJECTIVES

To appraise the literature by summarizing the findings of current evidence and clinical guidelines on the diagnosis and treatment of knee osteoarthritis pain.

METHODOLOGY

English journal articles that focused on knee osteoarthritis related pain were searched via PubMed (1 January 2002 - 26 August 2012) and Physiotherapy Evidence Database (PEDro) databases, using the terms 'knee', 'osteoarthritis' and 'pain'. In addition, reference lists from identified articles and related book chapters were included as comprehensive overviews.

RESULTS

For knee osteoarthritis, the highest diagnostic accuracy can be achieved by presence of pain and five or more clinical or laboratory criteria plus osteophytes. Some inconsistencies in the recommendations and findings were found between the clinical guidelines and systematic reviews. Generally, paracetamol, oral and topical non-steroidal anti-inflammatory drugs, opioids, corticosteroid injections and physical therapy techniques, such as therapeutic exercises, joint manual therapy and transcutaneous electrical nerve stimulation, can help reduce pain and improve function. Patient education programs and weight reduction for overweight patients are important to be considered.

CONCLUSIONS

Some inconsistencies in the recommendations and findings were found between the clinical guidelines and systematic reviews. However, it is likely that a combination of pharmacological and non-pharmacological treatments is most effective in treating patients with knee osteoarthritis.

[Pharmacological therapy of arthrosis]

The pharmacological management of osteoarthritis includes pure analgesia, anti-inflammatory drugs and substances supporting tissue maintenance in osteoarthritic joints. The decision for the treatment modality is made depending on the affected joint, the stage of the disease, the extent and frequency of inflammatory flares and the patient risk profile. This article gives an overview of the current treatment modalities including the advantages and disadvantages.