Safety and performance of Hydros and Hydros-TA for knee osteoarthritis: a prospective, multicenter, randomized, double-blind feasibility trial

Functionalized hydrogels as smart gene delivery systems to treat musculoskeletal disorders

Despite critical advances in regenerative medicine, the generation of definitive, reliable treatments for musculoskeletal diseases remains challenging. Gene therapy based on the delivery of therapeutic genetic sequences has strong value to offer effective, durable options to decisively manage such disorders. Furthermore, scaffold-mediated gene therapy provides powerful alternatives to overcome hurdles associated with classical gene therapy, allowing for the spatiotemporal delivery of candidate genes to sites of injury. Among the many scaffolds for musculoskeletal research, hydrogels raised increasing attention in addition to other potent systems (solid, hybrid scaffolds) due to their versatility and competence as drug and cell carriers in tissue engineering and wound dressing. Attractive functionalities of hydrogels for musculoskeletal therapy include their injectability, stimuli-responsiveness, self-healing, and nanocomposition that may further allow to upgrade of them as "intelligently" efficient and mechanically strong platforms, rather than as just inert vehicles. Such functionalized hydrogels may also be tuned to successfully transfer therapeutic genes in a minimally invasive manner in order to protect their cargos and allow for their long-term effects. In light of such features, this review focuses on functionalized hydrogels and demonstrates their competence for the treatment of musculoskeletal disorders using gene therapy procedures, from gene therapy principles to hydrogel functionalization methods and applications of hydrogel-mediated gene therapy for musculoskeletal disorders, while remaining challenges are being discussed in the perspective of translation in patients. STATEMENT OF SIGNIFICANCE: Despite advances in regenerative medicine, the generation of definitive, reliable treatments for musculoskeletal diseases remains challenging. Gene therapy has strong value in offering effective, durable options to decisively manage such disorders. Scaffold-mediated gene therapy provides powerful alternatives to overcome hurdles associated with classical gene therapy. Among many scaffolds for musculoskeletal research, hydrogels raised increasing attention. Functionalities including injectability, stimuli-responsiveness, and self-healing, tune them as "intelligently" efficient and mechanically strong platforms, rather than as just inert vehicles. This review introduces functionalized hydrogels for musculoskeletal disorder treatment using gene therapy procedures, from gene therapy principles to functionalized hydrogels and applications of hydrogel-mediated gene therapy for musculoskeletal disorders, while remaining challenges are discussed from the perspective of translation in patients.

Effects of Hyaluronic Acid With Intra-articular Corticosteroid Injections in the Management of Subtalar Post-traumatic Osteoarthritis - Randomized Comparative Trial

We investigated the potential of exogenous hyaluronic acid (HA) associated with corticosteroid injections to improve pain and function for the treatment of post-traumatic subtalar osteoarthritis, in comparison with isolated intra-articular corticosteroid. Twenty-five symptomatic participants (50 ± 8 years) with a minimum follow-up of 1 year after surgery for calcaneus fractures were enrolled. Participants were randomly assigned into a therapeutic group that underwent isolated corticosteroid intra-articular subtalar injection (Corticosteroid Group, n = 12) or a combination of HA plus corticosteroid (HA+C Group, n = 13). All participants underwent three repeated injections with intervals of 1 week. We assessed the visual analog scale of pain (VAS) and the AOFAS scores at 4 moments: before treatment (pre), 4-, 12-, and 24-weeks following the last injection. HA+C Group showed lower VAS at the 12th (p = .003) and 24th weeks (p = .003) and greater AOFAS at the 4th (p = 0.040), 12th (p = .014), and 24th weeks (p = .021), in comparison to Corticosteroid Group. We observed a reduction in VAS in the Corticosteroid Group only at the 4th week (p = .007), compared with pretreatment values. In the HA+C Group, VAS presented lower levels at the 4- (p < .001), 12- (p < .001), and 24 weeks (p < .001). In the Corticosteroid Group, participants presented higher AOFAS score only at the 4th week (p < .001), while in the HA+C Group, the AOFAS scores were greater at the 4th, 12th, and 24th weeks compared to baseline (p < .001). The combination of exogenous HA and corticosteroid showed greater and longer analgesic effects and function improvement in comparison with isolated intra-articular corticosteroids.

Cross-Linked Hyaluronate and Corticosteroid Combination Ameliorate the Rat Experimental Tendinopathy through Anti-Senescent and -Apoptotic Effects

The combination of cross-linked hyaluronate (cHA) and corticosteroid showed more rapid pain or functional improvement in knee osteoarthritis and adhesive capsulitis. However, rare evidence of this combination in treating tendinopathy has been reported. We hypothesized that the specific formulations of cHA and dexamethasone (DEX) conferred amelioration of tendinopathy via anti-apoptosis and anti-senescence. In this controlled laboratory study, primary tenocytes from the human tendinopathic long head of biceps were treated with three cHA formulations (cHA:linealized HA = 80:20, 50:50, and 20:80) + DEX with or without IL-1β stimulation. Cell viability, inflammatory cytokines, tendon-related proliferation markers, matrix metalloproteinases (MMPs), senescent markers, and apoptosis were examined. The in vivo therapeutic effects of the selected cHA + DEX combinations were evaluated in a collagenase-induced rat patellar tendinopathy model. The expression levels of inflammatory mediators, including IL-1β, IL-6, COX-2, MMP-1, and MMP-3 were significantly reduced in all cHA + DEX-treated tenocytes (p < 0.05, all). The cHA (50:50) + DEX and cHA (20:80) + DEX combinations protected tenocytes from cytotoxicity, senescence, and apoptosis induced by DEX in either IL-1β stimulation or none. Furthermore, the two combinations significantly improved the rat experimental tendinopathy by reducing ultrasound feature scores and histological scores as well as the levels of apoptosis, senescence, and senescence-associated secretory phenotypes (p < 0.05, all). We identified two specific cHA formulations (cHA (50:50) and cHA (20:80)) + DEX that could ameliorate tendinopathy through anti-senescence and -apoptosis without cytotoxicity. This study provides a possible approach to treating tendinopathy using the combination of two well-known agents.

Effects of Repeated Co-Injections of Corticosteroids and Hyaluronic Acid on Knee Osteoarthritis: A Prospective, Double-Blind Randomized Controlled Trial

BACKGROUND

We compared the effects of repeated co-injections of corticosteroids plus hyaluronic acid (HA) with the effects of HA injections alone in patients with knee osteoarthritis.

METHODS

A double-blind randomized controlled trial was conducted between October 2016 and July 2017 at a medical center. Patients (n = 57) who fulfilled the clinical and radiographic criteria for knee osteoarthritis established by the American College of Rheumatology with a Kellgren-Lawrence score of 2 or 3 were included. They were assigned to either the HA group (n = 29) or corticosteroids plus HA group (n = 28), and injections were administered under ultrasound guidance once a week for 3 consecutive weeks. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were the primary outcomes. Physical functional performance (10-m fast walking and chair-rising time) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were secondary outcomes. The assessment was performed prior to injections, 1 week, and 1, 3, and 6 months after injections. Data were analyzed through repeated-measures analysis of covariance.

RESULTS

Both groups experienced decreased pain and improved physical function and physical functional performance over time. We found significant group × time interaction effects favoring the corticosteroids plus HA group in WOMAC-pain (P = .005) and physical function (P = .005), chair-rising time (P = .032), and KOOS-pain (P = .001).

CONCLUSIONS

Repeated co-injections of corticosteroids plus HA more effectively decreased pain and improved physical function and physical functional performance than injections of HA alone from 1 week through 6 months posttreatment.

Management of osteoarthritis: From drug molecules to nano/micromedicines

With the change in lifestyle and aging of the population, osteoarthritis (OA) is emerging as a major medical burden globally. OA is a chronic inflammatory and degenerative disease initially manifesting with joint pain and eventually leading to permanent disability. To date, there are no drugs available for the definitive treatment of osteoarthritis and most therapies have been palliative in nature by alleviating symptoms rather than curing the disease. This coupled with the vague understanding of the early symptoms and methods of diagnosis so that the disease continues as a global problem and calls for concerted research efforts. A cascade of events regulates the onset and progression of osteoarthritis starting with the production of proinflammatory cytokines, including interleukin (IL)‐1β, IL‐6, tumor necrosis factor (TNF)‐α; catabolic enzymes, such as matrix metalloproteinases (MMPs)‐1, ‐3, and ‐13, culminating into cartilage breakdown, loss of lubrication, pain, and inability to load the joint. Although intra‐articular injections of small and macromolecules are often prescribed to alleviate symptoms, low residence times within the synovial cavity severely impair their efficacy. This review will briefly describe the factors dictating the onset and progression of the disease, present the current clinically approved methods for its treatment and diagnosis, and finally elaborate on the main challenges and opportunities for the application of nano/micromedicines in the treatment of osteoarthritis. Thus, future treatment regimens will benefit from simultaneous consideration of the mechanobiological, the inflammatory, and tissue degradation aspects of the disease.

This article is categorized under:

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology

Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement

Role and Effectiveness of Intra-articular Injection of Hyaluronic Acid in the Treatment of Knee Osteoarthritis: A Systematic Review

Osteoarthritis (OA) is a degenerative joint disease that causes persistent joint pain and stiffness of mainly the large peripheral weight-bearing joints. It is a leading cause of functional disability and poor quality of life. Various modalities of therapy are recommended by different research organizations at different stages of OA including non-pharmacological, pharmacological, and surgical interventions. Intra-articular injections of hyaluronic acid (HA) is widely used for over three decades in the treatment of OA. However controversies exist regarding its safety and efficacy, the number of injections and courses, type of preparation, duration of its effects, and combining it with other drugs or molecules. This study aimed to review the most recent data available in the published literature to address these. Electronic databases like Medline, Embase, ProQuest, and Google Scholar were searched for articles using keywords, intraarticular injections, hyaluronic acid, and osteoarthritis knee. The review was carried out as per PRISMA guidelines. Thirty-eight randomized control trials (RCTs) investigating the efficacy and safety of intra-articular injection of HA were included in the systematic review. Out of the 38 studies, 22 (57.9%) were double-blind, eight (21%) single-blind, three (7.9%) non-blind, four (10%) with simple randomization, and one (2.7%) was open-labeled. Total 5,025 patients were included in these studies. The mean age of the patients was 60.28 years and the osteoarthritis grade of the knee joint was 1 to 3. HA was studied as a test preparation in 19 (50%) while in another 19 (50%) it was studied as a control. In 24 (63.2%) studies, HA was used as high molecular weight preparation in eight (21%) as low molecular weight preparation while in six studies the information was not available. HA was used as a standalone preparation in 31 studies, in two studies it was injected with platelet-rich plasma (PRP) and with either low-level laser therapy (LLLT), triamcinolone (TA), betamethasone (CS), poly deoxyribonucleotide (PDRN) or dexamethasone (DX) in one study each. In the majority of the studies, HA was given as a single injection (52.6% studies) or weekly three injections (28.9% studies). In 13.2 %, it was given as weekly 5 injections and in 5.3% as weekly two injections. IA-HA injections have a limited role in the treatment of knee osteoarthritis in those patients who do not have sufficient pain relief with topical or oral medication and physical therapy. It is safe and effective except for minor side effects such as local pain and swelling lasting for a few days. Severe allergic reactions are extremely rare. They provide adequate pain relief and functional improvement for up to six months irrespective of a number of injections and type of preparations used. The combination formulations with corticosteroids or PRP or MSCs show better results than HA alone. Combining HA with newer molecules such as peptides or diclofenac for sustained and disease-modifying effects requires more studies in the future.

A Multicenter, Randomized, Double-Blinded, Parallel-Group, Placebo-Controlled Phase I/IIa Study to Evaluate the Efficacy and Safety of a Single Intra-Articular Injection of YYD302 in Patients with Knee Osteoarthritis

This study was a phase I/IIa, multicenter, randomized, double-blinded, parallel, placebo-controlled clinical trial that aimed to assess the efficacy and safety of a single intra-articular injection of YYD302, a novel high-molecular-weight hyaluronic acid with divinyl sulfone cross-linking. Thirty adults with knee osteoarthritis were randomized to receive a single 2 mL intra-articular injection of YYD302 (test group 1), 3 mL of YYD302 (test group 2), or 3 mL of the placebo (placebo group). We compared the changes from the baseline in the weight-bearing pain of 100 mm using the Visual Analog Scale (VAS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), the Rheumatology-Osteoarthritis Research Society International (OMERACT-OASRSI) responder rates, and the use of rescue analgesics to assess the safety of this novel drug. A total of 26 subjects (10 in test group 1, 10 in test group 2, and 6 in the placebo group) were included in the full analysis set. At 12 weeks, only test groups 1 and 2 showed significant changes in the weight-bearing pain VAS scores (p = 0.0015 and p = 0.0085), symptoms, and average daily KOOS values compared to the baseline (p < 0.001, p = 0.0124, and p = 0.0018, p = 0.0426, respectively). While the rate and frequency of consuming the rescue drug continued to increase in the placebo group until 12 weeks, there was no change in the test groups. Our findings showed that YYD302, especially 2 mL of YYD302, reduced pain and improved knee joint function compared to the placebo.

Recent Developments in Hyaluronic Acid-Based Hydrogels for Cartilage Tissue Engineering Applications

Articular cartilage lesions resulting from injurious impact, recurring loading, joint malalignment, etc., are very common and encompass the risk of evolving to serious cartilage diseases such as osteoarthritis. To date, cartilage injuries are typically treated via operative procedures such as autologous chondrocyte implantation (ACI), matrix-associated autologous chondrocyte implantation (MACI) and microfracture, which are characterized by low patient compliance. Accordingly, cartilage tissue engineering (CTE) has received a lot of interest. Cell-laden hydrogels are favorable candidates for cartilage repair since they resemble the native tissue environment and promote the formation of extracellular matrix. Various types of hydrogels have been developed so far for CTE applications based on both natural and synthetic biomaterials. Among these materials, hyaluronic acid (HA), a principal component of the cartilage tissue which can be easily modified and biofunctionalized, has been favored for the development of hydrogels since it interacts with cell surface receptors, supports the growth of chondrocytes and promotes the differentiation of mesenchymal stem cells to chondrocytes. The present work reviews the various types of HA-based hydrogels (e.g., in situ forming hydrogels, cryogels, microgels and three-dimensional (3D)-bioprinted hydrogel constructs) that have been used for cartilage repair, specially focusing on the results of their preclinical and clinical assessment.

Severe Acute Localized Reactions Following Intra-Articular Hyaluronic Acid Injections in Knee Osteoarthritis

OBJECTIVE

Concerns have been raised about severe acute localized reactions (SALR) following intra-articular (IA) hyaluronic acid (HA) injections for knee osteoarthritis (OA). We compared surrogate SALR measures between hylan G-F 20 and non-hylan G-F 20 HA patients and evaluated corresponding SALR risk factors for hylan G-F 20 patients.

DESIGN

Knee OA patients were identified from the Optum Clinformatics dataset (January 2006 to June 2016), stratified into hylan G-F 20 and non-hylan G-F 20 HA users. Occurrences of surrogate SALR measures including inflammation/infection, intra-articular corticosteroid (CS) injections, arthrocentesis/aspiration, and office visits were evaluated within 3 days of HA use. Risk factors were evaluated using logistic regression.

RESULTS

The cohort involved 748,428 HA patients (23.2% in the hylan G-F 20 group). Inflammation/infection rate was 0.001% for hylan G-F 20 and 0.002% for non-hylan G-F 20 HA groups. Risk of CS injection (any diagnosis) was greater for hylan G-F 20 patients by 28% (P < 0.001). Combined rates of CS injection and arthrocentesis/aspiration (any diagnosis) were comparable for both groups (hylan G-F 20, 2.2%; non-hylan G-F 20 HA, 2.6%). The risk of any visit or studied responses was lower for the hylan G-F 20 cohort by 12% (P < 0.001). Clinical characteristics, such as CS injections within 1 week before HA and fluoroscopic imaging, were associated with the outcomes.

CONCLUSIONS

The diagnosis of inflammations or infections within 3 days of the HA injection was extremely rare. The overall risk of surrogate SALR measures was similar for hylan G-F 20 and non-hylan G-F 20 HA patients.

Comparative analysis of intra-articular injection of steroid and/or sodium hyaluronate in adhesive capsulitis: prospective, double-blind, randomized, placebo-controlled study

Background

Few studies have reported the effects of simultaneous injections of corticosteroid (CS) and hyaluronic acid (HA) on adhesive capsulitis (AC) of the shoulder. This study investigated the synergistic effects of simultaneous intra-articular injections of CS and compared them to those of CS or HA alone.

Method

Sixty patients with AC were enrolled in this randomized, placebo-controlled trial. The participants were divided into 4 groups: saline, CS, HA, and CS with HA groups. The primary outcome measure was changes in the Shoulder Pain and Disability Index (SPADI) scores at one month. The secondary outcome measures included changes in pain, range of motion, muscle strength, and additional shoulder functional scores at 1 day, 1 week, and 1, 3, and 6 months after injection.

Results

After 1 month, changes of the SPADI scores were significantly higher in the CS with HA group (−58.4%) than those in the saline (−7.7%) and HA (−14.4%) groups. The score changed more in the CS with HA group than that in the CS group (−43.7%), but there was no significant difference. In the changes in pain, the CS with HA group showed significantly better and faster effects than the saline and HA groups. In the changes of range of motion, functional scores, the CS with HA group showed better results than the saline and HA groups.

Conclusion

In the treatment of AC, the simultaneous injection of CS and HA was more effective in improving SPADI scores at one month after injection than a single injection of CS or HA.

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.

Efficacy and Safety of Hylan G-F 20 Versus Intra-Articular Corticosteroids in People with Knee Osteoarthritis: A Systematic Review and Network Meta-Analysis

Background:

Direct injection of corticosteroids into the joint is a standard treatment for knee osteoarthritis (OA). However, the treatment is somewhat controversial with regard to the benefit of both single and repeated injections; evidence that they are beneficial comes from small studies that show only modest improvements. The aim of this study was to estimate the short- and long-term clinical efficacy and safety of hylan G-F 20 versus intra-articular corticosteroids (IACS) for the treatment of pain in knee OA using Bayesian network meta-analysis.

Methods:

Based on a pre-specified protocol, MEDLINE, Embase, and CENTRAL were searched from inception to June 2018 to identify randomized controlled trials. The Cochrane Collaboration’s tool for assessing risk of bias in randomized trials was used to assess the included studies. Hylan G-F 20 and IACS were compared using Bayesian network meta-analysis. Efficacy was evaluated at 1, 3, and 6 months, and at the final follow-up for safety outcomes. A pain hierarchy was used to select 1 pain outcome per study.

Results:

Forty-two trials were included for analysis. The network meta-analysis of pain showed that hylan G-F 20 may be equivalent to IACS in the short-term, but by 6 months the benefit relative to IACS was statistically significant, standardized mean difference (95% credible interval): –0.13 (–0.26, –0.01). There were no statistical differences in adverse events.

Conclusions:

Hylan G-F 20 may perform better in relieving pain at 6 months post-injection compared to IACS. Both agents were relatively well tolerated, with no clear differences in safety.

Evolution of hydrogels for cartilage tissue engineering of the knee: A systematic review and meta-analysis of clinical studies

INTRODUCTION

In recent years, studies have boosted our knowledge about the biology and disorders of articular cartilage. In this regard, the design of hydrogel-based scaffolds has advanced to improve cartilage repair. However, the efficacy of knee cartilage repair using hydrogels remains unclear. The aim of systematic review and meta-analysis was to scrutinize the efficiency of hydrogel-based therapy in correcting cartilage defects of knee (femoral condyle, patella, tibia plateau and trochlea).

METHODS

The search was conducted in PubMed to gather articles published from 2004/1/1 to 2019/10/01, addressing the effects of implant of hydrogel on knee joint cartilage regeneration. The Cochrane Collaboration's tool for estimating the risk of bias was applied to check the quality of articles. The clinical data for meta-analysis was recorded using the visual analog scale (VAS), Lysholm score, WOMAC, and IKDC. The guidelines of Cochrane Handbook for Systematic Reviews of Interventions were utilized to conduct the review and meta-analysis in the RevMan 5.3 software.

RESULTS

The search resulted in 50 clinical trials that included 2846 patients, 986 of whom received cell-based hydrogel implants while 1860 patients used hydrogel without cell. There were significant differences comparing the pain scores based on the VAS (MD: -2.97; 95% CI: -3.15 to -2.79, P<0.00001) and WOMAC (MD: -25.22; 95% CI: -31.22 to -19.22, P<0.00001) between pre- and post-treatment with hydrogels. Furthermore, there were significant improvements in the functional scores based on the IKDC total score (MD: 30.67; P<0.00001) and the Lysholm knee scale (MD: 29.26; 95% CI: 26.74 to 31.78, P<0.00001). According to the Lysholm and IKDC score and after cumulative functional analysis, there was a significant improvement in this parameter (MD: 29.25; 95% CI: 27.26 to 31.25, P<0.00001).

CONCLUSIONS

This meta-analysis indicated clinically and statistically significant improvements in the pain score (VAS and WOMAC) and the functional score (IKDC and Lysholm) after the administration of hydrogel compared to pretreatment status. So, the current evidence shows the efficiency of hydrogel-based therapy in correcting and repairing knee cartilage defects.

Lack of standardization among clinical trials of injection therapies for knee osteoarthritis: a systematic review

Purpose: Osteoarthritis (OA) of the knee is a debilitating, expensive, and prevalent disease, and interest in the non-surgical management of knee OA has grown recently. Our objective was to systematically assess the level of heterogeneity among all clinical trials and published studies regarding injections for knee osteoarthritis, in terms of treatment of interest, outcomes evaluated, and time points of outcome assessment. Methods: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were utilized to review all published studies and publically available clinical trials from 1 January 2013 to 3 May 2019evaluating intra-articular injections to treat knee OA. Their treatment group and specifics of methodology were scrutinized and compared. Results: 84 published studies and 114 clinical trials were included. Within the 84 published studies, the most common injection treatment studied was hyaluronic acid [N = 22; 26.2%]. In total, 29 different injection treatment groups were utilized. The most common time point for patient evaluation post-injection was 6 months (N = 33 studies; 50.0%), and ranged from 1 week (N = 9 studies; 13.6%) to 7 years (N = 1 study; 1.5%). The most common patient-reported outcome (PRO) measure assessed in the included studies was Western Ontario and McMaster's University Osteoarthritis Index (WOMAC) [N = 44 studies; 66.7%]. For the 114 clinical trials identified, the most common injection treatment studied is platelet-rich plasma in isolation (N = 19; 16.7%). Forty-two different injection treatment types/groups are utilized. The most common PRO measure assessed was WOMAC (N = 77 trials; 67.5%). Overall there were 34 different patient-reported outcome measures used. Conclusions: Research efforts to find the most effective injection therapy for knee OA continue with a tremendous number of injection therapies still being evaluated. Substantial heterogeneity exists in these completed and ongoing trials in terms of patient demographics, OA grades, outcome scores and relatively short-term timing of assessments, with no clear standardization of testing protocol despite proposing to answer the same clinical question. We recommend that studies of this genre going forward be standardized in terms of outcome measures and longer-term follow-up time points, and should incorporate functional assessment evaluations and imaging studies.

Injections intra articulaires (IA) d'acide hyaluronique (AH) dans le traitement symptomatique de la gonarthrose : une méta-analyse des injections uniques (mono-injections)

Introduction

La viscosupplémentation du liquide synovial par injections intra articulaires (IA) d'acide hyaluronique (AH), est un traitement symptomatique bien connu dans la gonarthrose. La question se pose de savoir si les traitements par injection unique (mono-injection) peuvent présenter autant d'efficacité que les multi-injections (3 à 5).

Méthodes

Une méta-analyse des résultats publiés pour les essais de mono-injections IA de AH a été réalisée. Le critère d'efficacité retenu a été le sous-score douleur de l'indice Western Ontario and MacMaster universities (WOMAC A). Toutes les conceptions d'études ont été admises, depuis les essais randomisés contrôlés jusqu'aux études observationnelles ouvertes à simple bras. Une recherche extensive a été effectuée à partir de PubMed, Google, Google Scholar, et des listes de références trouvées dans les méta-analyses récentes, pour obtenir tous les articles publiés avant fin avril 2018. Les profils des populations furent analysés en termes d'âge, de sexe, d'indice de masse corporelle (IMC) et de stade radiologique selon Kellgren-Lawrence (KL). Les résultats d'injection IA unique de placebo, ont été pris en compte pour créer une base permettant des comparaisons post-hoc. Chaque bras AH IA étudié a été comparé à un bras placebo IA (seul ou mixé), de manière à présenter un profil KL similaire, contrôlé à l'aide du test Chi². Les tailles de l'effet (ES) avec intervalles de confiance (IC 95%) et p-valeurs furent calculées et synthétisées pour chacune des visites de contrôle à 1, 2, 3 et 6 mois. En parallèle, une approche globale a été utilisée afin de représenter les variations par rapport à la baseline, pour chacun des sous-groupes étudiés.

Résultats

En partant de 1 547 citations, 28 études ont été incluses dans la méta-analyse, décrivant 4 129 patients traités par mono-injection: 3 360 ont reçu de l'AH IA et 769 patients ont reçu du placebo IA. Le patient moyen (SD) traité par AH IA était âgé de 61,2 (9,6) ans dont 63% de femmes, avec un IMC de 28,0 (4,1) kg/m², et un stade radiologique à 47% KL III pour 3% KL IV. Un bon appariement du profil KL a été obtenu pour 26 des 31 bras AH IA. Sur l'ensemble de la population AH IA, ES = 0,30 (0,25; 0,35) à 3 mois et ES = 0,39 (0,33; 0,44) à 6 mois. Dans une analyse restreinte, après élimination des cas aberrants, des KL mal appariés et des bras actifs < 30 patients, les résultats sont restés inchangés, ES = 0,29 (0,23; 0,34) et ES = 0,40 (0,34; 0,45) à 3 et 6 mois respectivement, tandis que l'hétérogénéité était améliorée.

Discussion

Il existe certainement des limites à la méthode de comparaison post-hoc versus placebo, appliquée à des essais individuels. Mais pour chaque synthèse par sous-groupe ou groupe, les résultats ont été confirmés en utilisant plusieurs approches statistiques et différentes méthodes de pondération. Cette méta-analyse suggère que les résultats des mono-injections sont similaires à ceux des multi-injections d'acide hyaluronique intra articulaire en termes de soulagement de la douleur, dans le traitement de la gonarthrose.

Combined intra-articular injection of corticosteroid and hyaluronic acid reduces pain compared to hyaluronic acid alone in the treatment of knee osteoarthritis

PURPOSE

Intra-articular injections of corticosteroid (CS) and hyaluronic acid (HA) have individually demonstrated efficacy for knee osteoarthritis (OA); however, both treatments are limited by the trajectory of symptom relief. The combination of CS and HA in the management of knee OA may provide improved symptomatic relief for patients who are candidates for intra-articular therapies.

METHODS

Electronic databases Medline, EMBASE and Cochrane Library were used to identify relevant publications. Randomized controlled trials (RCT) that evaluated intra-articular injections of combined CS and HA in comparison to HA alone were included. Outcomes eligible for meta-analysis were WOMAC pain, WOMAC total, OMERACT-OARSI responder rate, and treatment-related adverse events. Standardized mean differences (SMD) were calculated for continuous outcomes using an inverse variance method and a random-effects model. Odds ratios (OR) were calculated for dichotomous outcomes using the Mantel-Haenszel method and a random-effects model. Heterogeneity was assessed using the I² statistic.

RESULTS

Eight trials (n = 751 patients) were included. Reduction in WOMAC pain scores at 2-4 weeks favoured the combined CS and HA group compared to HA alone [SMD 0.60, 95% CI (0.23, 0.97); p = 0.002, I² = 75%]. Longer term improvements at 24-26 and 52 weeks WOMAC pain scores also favoured the combined CS and HA group {[SMD 0.25, 95% CI (0.09, 0.41); p = 0.002, I² = 0%] and [SMD 0.39, 95% CI (0.01, 0.77); p = 0.05, I² = 0%]} compared to HA alone, respectively. There were no significant differences in WOMAC total scores, OMERACT-OARSI responder rate, or treatment-related adverse events.

CONCLUSION

Combined intra-articular injections of CS and HA led to reductions in pain at 2-4, 24-26 and 52 weeks compared to HA injections alone.

LEVEL OF EVIDENCE

Level II-meta-analysis.

Towards reaching consensus on hyaluronic acid efficacy in knee osteoarthritis

Intra-articular injection of hyaluronic acid (HA) is a controversial treatment for knee osteoarthritis (OA). While clinical efficacy of HA relative to saline injections has been demonstrated in many studies, these results are of limited value in real-world clinical practice since saline injection is not a knee OA treatment. Instead, rigorous postmarket comparative studies of HA versus approved knee OA treatments are encouraged. The conduct of such studies is particularly important given the paucity and heterogeneous nature of current evidence regarding nonsurgical knee OA treatment. KEY POINTS: • Societal guidelines recommend nonsteroidal anti-inflammatory drugs and corticosteroid injections, but not hyaluronic acid injections, for knee osteoarthritis (OA) despite inconsistent supportive data. • This article encourages rigorous comparative post-approval studies to clarify the role of nonsurgical treatments used in clinical practice for knee OA.

Intra-Articular Hyaluronic Acid in the Symptomatic Treatment of Knee Osteoarthritis: A Meta-Analysis of Single-Injection Products

Background

Viscosupplementation of the synovial fluid with intra-articular hyaluronic acid (IA HA) is a well-known symptomatic treatment of knee osteoarthritis. The question arises whether a monoinjection (ie, single injection) could be as efficient as multi-injection (ie, 3-5 injections) regimens.

Methods

A meta-analysis of published studies relating to IA HA monoinjection trials was performed. The efficacy criterion was the Western Ontario and MacMaster Universities pain subscore. Any study design was accepted, from randomized control trials to single-arm observational open-label studies. An extensive search was performed using PubMed, Google, Google Scholar, and references found in recent meta-analyses, for all articles published before end of April 2018. Population profiles were analyzed in terms of age, sex, body mass index (BMI), and Kellgren-Lawrence (KL) radiology grades. Results of intra-articular single injection of placebo were collected to create a database allowing post hoc comparisons. Each IA HA study arm was compared to an IA placebo arm (either pooled or not), to present a similar KL profile controlled with the χ² test. The effect size (ES) (95% CI) and P values were calculated and synthesized for each follow-up visit at 1, 2, 3, and 6 months. In parallel, a global approach was used to represent the variations from baseline for each group or subgroup studied.

Results

From 1547 citations, 28 studies were included in the meta-analysis, representing 4129 patients treated with monoinjection: 3360 received IA HA and 769 patients received IA placebo. The mean (SD) IA HA patient was 61.2 (9.6) years, 63% women, BMI 28.0 (4.1), 47% KL III, and 3% KL IV. A good placebo KL profile matching was obtained for 26 of the 31 IA HA arms. For the whole IA HA population, ES = 0.30 (95% CI, 0.25-0.35) at 3 months and ES = 0.39 (95% CI, 0.33-0.44) at 6 months. In a restricted analysis, after removal of outliers, poorly KL matched and active arms <30 patients, results remained unchanged, ES = 0.29 (95% CI, 0.23-0.34) and ES = 0.40 (95% CI, 0.34-0.45) at 3 and 6 months respectively, whilst heterogeneity was improved.

Conclusions

There are certainly limits to the post hoc placebo comparison method, for individual studies. But for each synthesis per subgroup or group, the results were properly confirmed using multiple statistical approaches and weighing methods. This meta-analysis suggests that monoinjections produce results similar to multi-injections of IA HA in terms of pain relief in the treatment of knee osteoarthritis. (Curr Ther Res Clin Exp. 2019; 80:XXX-XXX).

Active viscosupplements for osteoarthritis treatment

OBJECTIVE

Osteoarthritis is a chronic, painful and disabling disease which prevalence is increasing in developing countries. Patients with osteoarthritis present a reduced synovial fluid viscoelasticity due to a reduction in concentration and molecular weight of hyaluronic acid. Currently, the main treatment used to restore the compromised rheological properties of synovial fluid is the viscosupplementation by hyaluronic acid injections that can be combined with oral anti-inflammatory drugs for pain relief. Combination of viscosupplements with chemical agents or drugs is emerging as a new strategy to provide a double action of synovial fluid viscoelasticity recovery and the therapeutic effect of the bioactive principle.

METHODS

In this review, we present the latest research on the combination of viscosupplements with active molecules. We conducted a literature review of articles published in different web search engines and categorized according to the active molecule introduced into the viscosupplement.

RESULTS

Generally, the introduction of anti-inflammatory molecules have shown to improve pain relief although some cytotoxicity has been demonstrated especially for non-steroidal anti-inflammatory drugs. Other molecules such as antioxidant or disease modifying osteoarthritis drugs have been reported to improve viscosupplementation action. Drug delivery systems combined with hyaluronic acid could enhance the activity of the encapsulated molecules and provide better control over the drug release. Finally, biological approaches such as the use of stem cells or platelet-rich plasma seem to be the most promising strategies for cartilage recovery.

CONCLUSIONS

Combination therapy of viscosupplements with therapeutic agents, drug delivery systems or regenerative therapies can improve viscosupplementation outcome in terms of pain relief and joint functionality. However, further research is needed in order to reach more conclusive results.

Safety and Efficacy of Repeat Administration of Triamcinolone Acetonide Extended-release in Osteoarthritis of the Knee: A Phase 3b, Open-label Study

Introduction

The aim of this work is to assess the safety and efficacy of repeat administration of triamcinolone acetonide extended-release (TA–ER) in patients with symptomatic knee osteoarthritis (OA), including those with advanced radiographic severity.

Methods

In this phase 3b, single-arm, open-label study, patients aged ≥ 40 years received the first intra-articular TA-ER injection on day 1. Patients received the second injection timed to the response to the first injection (at either week 12, 16, 20, or 24). Patients who received two injections were evaluated every 4 weeks for 52 weeks. Safety was evaluated via treatment-emergent adverse events and any change at 52 weeks in index-knee radiographs (chondrolysis, osteonecrosis, insufficiency fractures, subchondral bone changes). Exploratory efficacy endpoints included Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)-A (pain), -B (stiffness), -C (function), and Knee Injury and Osteoarthritis Outcome Score-Quality of Life (KOOS-QoL) after each injection. Initiative in Methods, Measurements and Pain Assessment in Clinical Trials (IMMPACT) criteria were used to determine moderate and substantial treatment response.

Results

A total of 208 patients were enrolled and received the first injection of TA-ER; 179 (86.1%) received the second injection (median time to second injection: 16.6 weeks). Both injections were well tolerated, with no unexpected adverse events or significant radiographic changes at week 52. The magnitude and duration of clinical benefit after the first and second injections were similar, and most patients reported a substantial (≥ 50%) analgesic response after both doses.

Conclusions

Repeat administration of TA–ER using a flexible dosing schedule timed to patient response was well tolerated, with no radiographic evidence of cartilage impact. Both injections resulted in similar improvements in OA symptoms across a broad spectrum of disease severity reflective of that seen in clinical practice.

Trial Registration Information

ClinicalTrials.gov identifier: NCT03046446.

Funding

Flexion Therapeutics, Inc.

Plain Language Summary

Plain language summary available for this article.

Electronic supplementary material

The online version of this article (10.1007/s40744-019-0140-z) contains supplementary material, which is available to authorized users.

Corticosteroids injections versus corticosteroids with hyaluronic acid injections in rhizarthrosis: the randomised multicentre RHIZ'ART trial study protocol

INTRODUCTION

Osteoarthritis of the trapeziometacarpal joint affects approximately 10%-25% of women, especially those who are postmenopausal. It may result in thumb dysfunction. Among the treatments, intra-articular injections of corticosteroid (CS) and hyaluronic acid (HA) are both effective and recommended. However, clinical trials have shown that HA improves functional capacity, whereas CS only produces a decrease in pain. The synergy of these two drugs has not been evaluated. The primary goal of this study was to determine whether the association between HA and CS produce an additional decrease of more pain during thumb movement at three months postinjection, compared to the level of pain relief from CS alone.

METHODS AND ANALYSIS

RHIZ'ART is a prospective, multicentre, comparative, randomised, controlled, double-blind trial. Patients referred to the rheumatology department for thumb rhizarthrosis will receive an injection of betamethasone with HA or placebo (serum saline) based on central randomisation and stratification by centre. Injections will be given under ultrasound guidance. The primary outcome will compare the pain Visual Analogue Scale with motion at three months for both groups using a mixed model. The expected decrease in pain intensity in the CS group is 25% and 35% in the CS with HA group. In order to achieve a 80% power for detecting this difference with α set at 5%, 73 patients are needed in each group (146 total). The main secondary outcomes are the Cochin score (hand function) and grip strength. Follow-up visits are at 1, 3, 6 and 12 months.

ETHICS AND DISSEMINATION

The study project has been approved by the appropriate ethics committee (CPP île de France III, 2017-002298-20). In agreement with current French regulations, a signed informed written consent will be obtained from each patient. Results of the main trial and of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03431584.

Origin and Efficacy of Hyaluronan Injections in Knee Osteoarthritis: Randomized, Double-Blind Trial

BACKGROUND Several hyaluronan preparations are available that have different dosage forms, origins, and concentrations. The objective of the study was to compare the efficacy of intra-articular chemically cross-linked hyaluronan (CCH) and avian-derived hyaluronan (ADH) injections in knee osteoarthritis (KOA) patients. MATERIAL AND METHODS In total, 258 patients were randomized into 2 groups of 129 each: patients who received CCH injection (CCH group) and patients who received ADH injection (ADH group). Radiographic Kellgren-Lawrence score, visual analog scale (VAS) pain score, Lequesne index score, the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index, single-limb stance (SLS) test, and timed "Up-and-Go" (TUG) test were performed. The Mann-Whitney U test or independent t-test following Bonferroni adjustment was performed for statistical analysis at 95% of confidence level. RESULTS The CCH group had improved VAS pain score (P<0.0001, q=54.803), total WOMAC score (P<0.0001, q=4.753), Lequesne index score (P<0.0001, q=3.208), and SLS time (P<0.0001, q=8.76) at the end of 6 months as compared to those in the ADH group. After 6 months of follow-up, the ADH group had improved TUG time (P=0.0148, q=3.385) as compared to baseline. Both groups of patients had the similar improvement in Kellgren-Lawrence score and mild to moderate adverse effects after 6 months. CONCLUSIONS CCH injection was superior to ADH injection.

[Pharmacological treatment of osteoarthritis-related pain]

Joint pain due to osteoarthritis (OA) is often severe and disabling and affects a large proportion of the aging population impairing daily living and quality of life. Numerous pharmacological treatment approaches are available. Including major OA guidelines this review presents the current evidence of pharmacological therapies in OA-related pain and covers topical, oral and intraarticular treatment approaches. In patients with mild OA topical nonsteroidal antiinflammatory drugs (NSAIDs) can be recommended. Topical capsaicin can be used when other treatments are ineffective or contraindicated. In patients with moderate to severe OA oral NSAIDs are suggested at the lowest effective dose for the shortest possible duration to control symptoms. Importantly, drug-related side effects and gastrointestinal, cardiovascular and renal comorbidities need to be taken into account. In patients with multiple-joint OA and high risk of NSAID-induced adverse events duloxetine can be considered. The evidence of metamizole, symptomatic slow-acting drugs in osteoarthritis and other nutritional supplements in the treatment of OA pain is uncertain and the use of opioids is not routinely recommended. In patients suffering from severe OA-related pain intraarticular injections with glucocorticoids can be suggested to achieve short-term pain relief. Evidence for interventional approaches using hyaluronic acid or platelet-rich plasma is uncertain. Yet, the efficacy of pharmacological therapies in OA-related pain is often inconsistent and severe adverse events might occur. Thus, critical use of the different treatment options considering patient-related comorbidities and nonpharmacological therapies is of major importance.

Do intra-articular hyaluronic acid injections delay total knee replacement in patients with osteoarthritis - A Cox model analysis

Due to the growing worldwide prevalence of knee osteoarthritis, the optimal management of this issue is critical for reducing its burden.

Effects of hyaluronic acid combined with anti-inflammatory drugs compared with hyaluronic acid alone, in clinical trials and experiments in osteoarthritis: a systematic review and meta-analysis

Background

The objectives are to compare the efficacy of intra-articular hyaluronic acid (IA-HA) alone and in combination with anti-inflammatory drugs (IA-HA + AI), corticosteroids (CS) or non-steroidal anti-inflammatory drugs (NSAIDs) in clinical trials and in vivo and in vitro studies of osteoarthritis (OA).

Methods

Data in the BIOSIS, CINAHL, Cochrane Library, EMBASE and Medline databases were collected and analyzed. Random effects models were used to compute the effect size (ES) of the mean difference in pain reduction scores from baseline and the relative risk (RR) of adverse events. The ES of histological scores in vivo and cartilage metabolism in vitro were also calculated. We conducted sensitivity analysis of blinding and intention-to-treat (ITT), compared IA-HA combined with CS vs. IA-HA alone in trials, and compared the effects of HA + AI vs. AI alone in vitro, including anabolic and catabolic gene expression.

Results

Thirteen out of 382 papers were included for data analysis. In clinical trials, the ES of pain reduction scores within the 1st month was −4.24 (−6.19, −2.29); 2nd–12th month, −1.39 (−1.95, −0.82); and within one year, −1.63 (−2.19, −1.08), favoring IA-HA + AI (P < 0.001). The ES of RR was 1.08 (0.59, 1.98), and histological scores was 1.38 (−0.55, 3.31). The ES of anabolic gene expression was 1.22 (0.18, 2.25), favoring HA alone (P < 0.05); catabolic gene expression was 0.74 (−0.44, 1.53), favoring HA alone; and glycosaminoglycans remaining was −2.45 (−5.94, 1.03).

Conclusions

IA-HA + AI had greater efficacy for pain relief than IA-HA alone within a one-year period. However, HA + AI down-regulated the ACAN gene when compared with HA alone in vitro.

The safety of intra-articular injections for the treatment of knee osteoarthritis: a critical narrative review

INTRODUCTION

International guidelines recommend that the management of knee osteoarthritis (OA) combine both nonpharmacological and pharmacological interventions. Intra-articular (IA) therapies are considered part of this multimodal approach and are well-established Food and Drug Administration (FDA) and European Medicines Agency (EMA)-approved treatments. Areas covered: Safety data for knee OA, including IA corticosteroids, hyaluronic acid, platelet-rich plasma and botulinum toxin are critically reviewed, and evidence- and pratice-based measures to improve safety of IA therapies are discussed. Expert opinion: The incidence of AEs attributable to IA therapies across clinical trials in knee OA is very low, and barely reaches significance when compared to the incidence of AEs in the comparator group. These events are exceptionally serious. Mild differences between products have been inconsistently reported mainly for IA HA. One can distinguish self-limited AEs such as post-injection pain and swelling that are the most frequently reported AEs, from AEs that are not self-limited but rare such as septic arthritis. The safety of IA therapies can be improved by applying simple measures designed to prevent AEs. However, even though no specific safety concerns have been raised to date about IA therapies, the quality of evidence is low, and there is a need to improve the monitoring and reporting of safety data from clinical trials and post-marketing surveillance.

Cost-Utility of a Single-Injection Combined Corticosteroid-Hyaluronic Acid Formulation vs a 2-Injection Regimen of Sequential Corticosteroid and Hyaluronic Acid Injections

Research has shown early and sustained relief with a combination therapy of a corticosteroid (CS) and hyaluronic acid (HA) in knee osteoarthritis (OA) patients. This can be administered via a single injection containing both products or as separate injections. The former may be more expensive when considering only product cost, but the latter incurs the additional costs and time of a second procedure. The purpose of this study was to compare the cost-utility of the single injection with the 2-injection regimen. The results of this analysis revealed that the single-injection formulation of a CS and HA may be cost-effective, assuming a willingness-to-pay of $50 000 per quality-adjusted life year gained, for symptomatic relief of OA symptoms. This treatment may also be more desirable to patients who find injections to be inconvenient or unpleasant.

Comparison of Single Intra-Articular Injection of Novel Hyaluronan (HYA-JOINT Plus) with Synvisc-One for Knee Osteoarthritis: A Randomized, Controlled, Double-Blind Trial of Efficacy and Safety

BACKGROUND

Viscosupplementation has been widely used for the treatment of knee osteoarthritis. Because we found no well-controlled trial comparing single-injection regimens of hyaluronan for knee osteoarthritis, we compared the efficacy and safety of a single intra-articular injection of a novel cross-linked hyaluronan (HYA-JOINT Plus) with a single injection of Synvisc-One in patients with knee osteoarthritis.

METHODS

In a prospective, randomized, controlled, double-blind trial with a 6-month follow-up, 132 patients with knee osteoarthritis (Kellgren-Lawrence grade 2 or 3) were randomized to receive 1 intra-articular injection of 3 mL of HYA-JOINT Plus (20 mg/mL) (n = 66) or 6 mL of Synvisc-One (8 mg/mL) (n = 66). The primary outcome was the change from baseline in the visual analog scale (VAS) (0 to 100 mm) pain score at 6 months. Secondary outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC, Likert scale), Lequesne index, timed "Up & Go" (TUG) test, single-limb stance (SLS) test, use of rescue analgesics, and patient satisfaction.

RESULTS

A total of 121 patients were available for the intention-to-treat analysis at 6 months. Both groups had a significant improvement in the VAS, WOMAC, and Lequesne index scores at each follow-up visit (p < 0.001). Patients who received HYA-JOINT Plus experienced a significantly greater improvement in the VAS pain score at 1, 3, and 6 months compared with those treated with Synvisc-One (adjusted mean difference: -12.0, -8.5, and -6.6; p = 0.001, 0.033, and 0.045, respectively). There were no significant between-group differences in any of the secondary outcomes except the WOMAC stiffness scores at 6 months, which favored HYA-JOINT Plus treatment (p = 0.043). The TUG time did not change significantly in either group during the study (p > 0.05), but the SLS time improved significantly in both the HYA-JOINT Plus and the Synvisc-One group (p = 0.004 and p = 0.022, respectively). No significant between-group differences were observed with respect to patient satisfaction or consumption of analgesics. No serious adverse events occurred following the injections.

CONCLUSIONS

A single injection of either HYA-JOINT Plus or Synvisc-One is safe and effective for 6 months in patients with knee osteoarthritis. HYA-JOINT Plus is superior to Synvisc-One in terms of reducing the VAS pain score at 1, 3, and 6 months and the WOMAC stiffness score at 6 months, with similar safety.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Cartilage-targeting drug delivery: can electrostatic interactions help?

Current intra-articular drug delivery methods do not guarantee sufficient drug penetration into cartilage tissue to reach cell and matrix targets at the concentrations necessary to elicit the desired biological response. Here, we provide our perspective on the utilization of charge-charge (electrostatic) interactions to enhance drug penetration and transport into cartilage, and to enable sustained binding of drugs within the tissue's highly negatively charged extracellular matrix. By coupling drugs to positively charged nanocarriers that have optimal size and charge, cartilage can be converted from a drug barrier into a drug reservoir for sustained intra-tissue delivery. Alternatively, a wide variety of drugs themselves can be made cartilage-penetrating by functionalizing them with specialized positively charged protein domains. Finally, we emphasize that appropriate animal models, with cartilage thickness similar to that of humans, must be used for the study of drug transport and retention in cartilage.

Intraarticular slow-release triamcinolone acetate reduces allodynia in an experimental mouse knee osteoarthritis model

Intraarticular steroid injection has been the mainstay of short-term treatment of knee osteoarthritis (OA) pain. However, the duration of therapeutic effect from a single injection is not as long as desired. In this study we use a viscous formulation of triamcinolone acetate (TCA) in hyaluronic acid to prolong the anti-allodynia effect of that steroid. OA was induced in mice by a partial medial meniscectomy. Over time the animals' developed a mechanical allodynia in the injected leg. Mice were then given a single intraarticular injection of TCA in a short-acting DMSO formulation, or a standard commercial suspension, or the drug formulated in 5% hyaluronic acid for slow-release. Control injections in OA mice were PBS or 5% hyaluronic acid vehicle. Mechanical allodynia was then monitored over the therapeutic period. Organotypic spinal cord slices and DRG culture were performed to assess whether TCA attenuates expressions of pain mediators induced by interleukin 1β. TCA 40μg in a fast-releasing DMSO formulation produced relief from mechanical allodynia for a few days compared to PBS control injections (P=0.007). Similarly, the commercial suspension of TCA 40μg also produced relief from mechanical allodynia for a few days compared to PBS control injections (P=0.001). However, TCA 100μg in 5% hyaluronic acid produced relief from mechanical allodynia for at least 28days compared to PBS control or 5% hyaluronic acid vehicle injections (P=0.0005). Furthermore, TCA significantly suppressed expression of pain mediators induced by interleukin 1β in spinal cord and DRG organotypic culture. Intraarticular TCA in a sustained release formulation of viscous 5% hyaluronic acid will produce a long-term attenuation of mechanical allodynia in the OA knees of mice.