OARSI Clinical Trials Recommendations: Design, conduct, and reporting of clinical trials for knee osteoarthritis

The goal of this document is to update the original OARSI recommendations specifically for the design, conduct, and reporting of clinical trials that target symptom or structure modification among individuals with knee osteoarthritis (OA). To develop recommendations for the design, conduct, and reporting of clinical trials for knee OA we initially drafted recommendations through an iterative process. Members of the working group included representatives from industry and academia. After the working group members reviewed a final draft, they scored the appropriateness for recommendations. After the members voted we calculated the median score among the nine members of the working group who completed the score. The document includes 25 recommendations regarding randomization, blocking and stratification, blinding, enhancing accuracy of patient-reported outcomes (PRO), selecting a study population and index knee, describing interventions, patient-reported and physical performance measures, structural outcome measures, biochemical biomarkers, and reporting recommendations. In summary, the working group identified 25 recommendations that represent the current best practices regarding clinical trials that target symptom or structure modification among individuals with knee OA. These updated recommendations incorporate novel technologies (e.g., magnetic resonance imaging (MRI)) and strategies to address the heterogeneity of knee OA.

Bone sialoprotein as a potential key factor implicated in the pathophysiology of osteoarthritis

OBJECTIVE

We previously identified an association between bone sialoprotein (BSP) and osteoarthritic (OA) chondrocyte hypertrophy but the precise role of BSP in ostearthritis (OA) has not been extensively studied. This study aimed to confirm the association between BSP and OA chondrocyte hypertrophy, to define its effect on molecules produced by chondrocytes and to analyse its association with cartilage degradation and vascular density at the osteochondral junction.

METHOD

Human OA chondrocytes were cultivated in order to increase hypertrophic differentiation. The effect of parathyroid hormone-related peptide (PTHrP), interleukin (IL)-1β or tumour necrosis factor (TNF)-α on BSP was analysed by real-time reverse transcription polymerase chain reaction (RT-PCR) and western blot. The effects of BSP on OA chondrocytes production of inflammatory response mediators (IL-6, nitric oxide), major matrix molecule (aggrecan), matrix metalloprotease-3 and angiogenic factors (vascular endothelial growth factor, basic fibroblast growth factor, IL-8, and thrombospondin-1) were investigated. BSP was detected by immunohistochemistry and was associated with cartilage lesions severity and vascular density.

RESULTS

PTHrP significantly decreased BSP, confirming its association with chondrocyte hypertrophy. In presence of IL-1β, BSP stimulated IL-8 synthesis, a pro-angiogenic cytokine but decreased the production of TSP-1, an angiogenesis inhibitor. The presence of BSP-immunoreactive chondrocytes in cartilage was associated with the severity of histological cartilage lesions and with vascular density at the osteochondral junction.

CONCLUSION

This study supports the implication of BSP in the pathology of OA and suggests that it could be a key mediator of the hypertrophic chondrocytes-induced angiogenesis. To control chondrocyte hypertrophic differentiation is promising in the treatment of OA.

OARSI guidelines for the non-surgical management of knee osteoarthritis

OBJECTIVE

To develop concise, up-to-date, patient-focused, evidence-based, expert consensus guidelines for the management of knee osteoarthritis (OA), intended to inform patients, physicians, and allied healthcare professionals worldwide.

METHOD

Thirteen experts from relevant medical disciplines (primary care, rheumatology, orthopedics, physical therapy, physical medicine and rehabilitation, and evidence-based medicine), three continents and ten countries (USA, UK, France, Netherlands, Belgium, Sweden, Denmark, Australia, Japan, and Canada) and a patient representative comprised the Osteoarthritis Guidelines Development Group (OAGDG). Based on previous OA guidelines and a systematic review of the OA literature, 29 treatment modalities were considered for recommendation. Evidence published subsequent to the 2010 OARSI guidelines was based on a systematic review conducted by the OA Research Society International (OARSI) evidence team at Tufts Medical Center, Boston, USA. Medline, EMBASE, Google Scholar, Web of Science, and the Cochrane Central Register of Controlled Trials were initially searched in first quarter 2012 and last searched in March 2013. Included evidence was assessed for quality using Assessment of Multiple Systematic Reviews (AMSTAR) criteria, and published criticism of included evidence was also considered. To provide recommendations for individuals with a range of health profiles and OA burden, treatment recommendations were stratified into four clinical sub-phenotypes. Consensus recommendations were produced using the RAND/UCLA Appropriateness Method and Delphi voting process. Treatments were recommended as Appropriate, Uncertain, or Not Appropriate, for each of four clinical sub-phenotypes and accompanied by 1-10 risk and benefit scores.

RESULTS

Appropriate treatment modalities for all individuals with knee OA included biomechanical interventions, intra-articular corticosteroids, exercise (land-based and water-based), self-management and education, strength training, and weight management. Treatments appropriate for specific clinical sub-phenotypes included acetaminophen (paracetamol), balneotherapy, capsaicin, cane (walking stick), duloxetine, oral non-steroidal anti-inflammatory drugs (NSAIDs; COX-2 selective and non-selective), and topical NSAIDs. Treatments of uncertain appropriateness for specific clinical sub-phenotypes included acupuncture, avocado soybean unsaponfiables, chondroitin, crutches, diacerein, glucosamine, intra-articular hyaluronic acid, opioids (oral and transdermal), rosehip, transcutaneous electrical nerve stimulation, and ultrasound. Treatments voted not appropriate included risedronate and electrotherapy (neuromuscular electrical stimulation).

CONCLUSION

These evidence-based consensus recommendations provide guidance to patients and practitioners on treatments applicable to all individuals with knee OA, as well as therapies that can be considered according to individualized patient needs and preferences.

Consequences of chondrocyte hypertrophy on osteoarthritic cartilage: potential effect on angiogenesis

OBJECTIVE

The aim of this study was to investigate the link between the hypertrophic phenotype of chondrocytes and angiogenesis in osteoarthritis (OA) and more particularly to demonstrate that OA hypertrophic chondrocytes potentially express a phenotype promoting angiogenesis through the expression of factors controlling endothelial cells migration, invasion and adhesion.

METHOD

Human OA chondrocytes were cultivated in alginate beads in medium supplemented with 10% fetal bovine serum (FBS) to induce chondrocyte hypertrophy. The hypertrophic phenotype was characterized throughout 28 days of culture by measuring the expression of specific genes and by a microscopic observation of cellular morphology. The effect of media conditioned by OA hypertrophic chondrocyte on endothelial cells migration, invasion and adhesion was evaluated in functional assays. Moreover, hypertrophic OA chondrocytes were tested for the expression of angiogenic factors by real-time RT-PCR.

RESULTS

Specific markers of hypertrophy and observation of cellular morphology attested of the hypertrophic phenotype of chondrocytes in our culture model. Functional angiogenesis assays showed that factors produced by hypertrophic chondrocytes stimulated migration, invasion and adhesion of endothelial cells. Among the evaluated angiogenic factors, bone sialoprotein (BSP) was the most highly upregulated in hypertrophic chondrocytes. The inhibition of endothelial cell adhesion by a GRGDS peptide confirmed the implication of RGD domain proteins, like BSP, in hypertrophic chondrocyte-induced adhesion of endothelial cells.

CONCLUSION

Hypertrophic differentiation of chondrocyte may promote angiogenesis. Our findings established the relation of BSP with OA chondrocyte hypertrophy and suggested that this factor could constitute a potential target to control cartilage neovascularisation in OA.

Protective effect of a new biomaterial against the development of experimental osteoarthritis lesions in rabbit: a pilot study evaluating the intra-articular injection of alginate-chitosan beads dispersed in an hydrogel

OBJECTIVE

This study aimed to evaluate the structural benefit of a new biomaterial composed of alginate-chitosan (AC) beads dispersed in a hydrogel (H) derived from chitosan on the development of osteoarthritis (OA) in rabbit.

DESIGN

OA was induced by the surgical transection of the anterior cruciate ligament in rabbits. Animals received a single intra-articular injection (900 μl) of AC beads in H hydrogel, H hydrogel alone or saline a week after surgery. OA development was followed by X-rays. Blood samples were collected throughout the study to measure biological markers (Prostaglandins E2 - PGE2 and C reactive protein - CRP). Macroscopic observation and histological evaluation of articular cartilage and synovial membrane were performed 6 weeks after surgery.

RESULTS

AC beads in H hydrogel prevented from the development of OA based on the reduction of the Kellgren & Lawrence (K&L) score. It also significantly reduced the histological score of cartilage lesion severity. This effect was homogenous on every joint compartment. It was due to a significant effect on cartilage structure and cellularity scores. The injection of AC beads in H hydrogel also tended to reduce the synovial membrane inflammation. No significant variation of biological markers was noted.

CONCLUSIONS

The present pilot study provides interesting and promising results for the use of AC beads in H hydrogel in animal. It indeed prevented the development of OA cartilage lesions without inflammatory signs. The potencies of this biomaterial to protect OA joint should be further documented. It could then represent a new alternative for viscosupplementation in human OA management.

Identification of differential pattern of protein expression in canine osteoarthritis serum after anterior cruciate ligament transection: a proteomic analysis

Osteoarthritis (OA) management remains a great challenge and there is considerable effort to understand its pathophysiology and to identify new therapeutic targets and biomarkers. Canine OA surgically induced by the transection of the anterior cruciate ligament (ACLT) is a widely used and relevant model. This study reports a proteome mapping of dog serum and an analysis of the differentially expressed proteins between before and after ACLT. In the first part of the study, 261 picked protein spots were identified from preparative 2D gels and 71 different proteins were identified among the 261 spots present on the reference map. Canine serum proteome mapping reveals the presence of proteins of interest, such as fetuin B, complement C3 and C1s and pregnancy zone protein. The comparison between serum from dogs before and after ACLT reveals the differential expression of several proteins that could play a key role in the pathogenesis of OA. A number of proteins, such as fetuin B and complement C3, were increased in dog OA serum whereas others, such as hyaluronan binding protein 2, inter-alpha-trypsin inhibitor H4 (ITIH4), complement C1s and C4 and haptoglobin were decreased. Some of these proteins could be candidate biomarkers for diagnosis, prognosis and treatment evaluation. The results of the study also reinforced the similarities between dog experimental OA and human cases of OA.

Early decrease of serum biomarkers of type II collagen degradation (Coll2-1) and joint inflammation (Coll2-1 NO₂ ) by hyaluronic acid intra-articular injections in patients with knee osteoarthritis: a research study part of the Biovisco study

To measure the evolution of the serum levels of specific Osteoarthritis (OA) biomarker, Coll2-1 and Coll2-1 NO₂ in knee osteoarthritic patients after viscosupplementation (VS). Fifty-one patients with unilateral symptomatic knee were recruited for this prospective open label study. They received three intra-articular injections of 2 ml of hyaluronic acid (Hylan GF-20) and were followed for 3 months. Walking pain was evaluated and serum samples were taken at each visit. Coll2-1 and Coll2-1 NO₂ were measured in the serum using specific immunoassays. Variations over time of each parameter and predictive factor of response were studied. Forty-five patients were analyzed. The serum concentrations of Coll2-1 and Coll2-1 NO₂ were significantly higher in KL III/IV patients compared to KL I/II patients at baseline and decreased systematically over time after VS. Its effect was ever more pronounced in patients with KL III/IV. The serum concentration of Coll2-1 was significantly lower at baseline in responders than in non-responders. This study suggests a rapid slowdown of type II collagen degradation and joint inflammation after VS with Hylan G-20 and gives additional information for the validation of accurate biomarkers for OA. The serum level of Coll2-1 appeared to be a predictive factor for response to treatment.

Symptom and structure modification in osteoarthritis with pharmaceutical-grade chondroitin sulfate: what's the evidence?

OBJECTIVES

Osteoarthritis is a chronic disease characterized by irreversible damage to joint structures, including loss of articular cartilage, osteophyte formation, alterations in the subchondral bone and synovial inflammation. It has been shown that chondroitin sulfate interferes with the progression of structural changes in joint tissues and is used in the management of patients with osteoarthritis.

METHODS

This review summarizes data from relevant reports describing the mechanisms of action of chondroitin sulfate that may explain the beneficial effects of the drug and examines the evidence for clinical efficacy of oral chondroitin sulfate in osteoarthritis. Data included in the review were derived from a literature search in PubMed. Literature searches were performed in PubMed using the search terms 'chondroitin sulfate', 'pharmaceutical-grade', 'osteoarthritis', 'randomized clinical trials', 'humans'. The MEDLINE database was searched from January 1996 through August 2012 for all randomized controlled trials, meta-analyses, systematic reviews, and review articles of chondroitin sulfate in osteoarthritis.

RESULTS

Chondroitin sulfate exerts in vitro a beneficial effect on the metabolism of different cell lines: chondrocytes, synoviocytes and cells from subchondral bone, all involved in osteoarthritis. It increases type II collagen and proteoglycan synthesis in human articular chondrocytes and is able to reduce the production of some pro-inflammatory factors and proteases, to reduce the cellular death process, and improve the anabolic/catabolic balance of the extracellular cartilage matrix (ECM). Clinical trials have reported a beneficial effect of chondroitin sulfate on pain and function. The structure-modifying effects of chondroitin sulfate have been reported and analyzed in recent meta-analyses. The results in knee osteoarthritis demonstrate a small but significant reduction in the rate of decline in joint space width. Because chondroitin sulfate quality of several nutraceuticals has been found to be poor, it is recommended that pharmaceutical-grade chondroitin sulfate is used rather than food supplements in the treatment of OA. Chondroitin sulfate is recommended by several guidelines from international societies in the management of knee and hip OA. Furthermore, its safety profile is favorable when compared with many other therapies used in OA.

CONCLUSION

Chondroitin sulfate is an effective and safe treatment option for patients with osteoarthritis.

Effectiveness of preventive back educational interventions for low back pain: a critical review of randomized controlled clinical trials

PURPOSE

A systematic search was conducted to study the efficiency of preventive educational interventions mainly focused on a biomechanical/biomedical model.

METHODS

The PubMed electronic database and the Cochrane Library were searched based on a combination of keywords related to low back pain (LBP) and posture education. Only randomized controlled trial (RCT) studying the efficiency on outcomes directly related to LBP of a preventive intervention programme mainly based on education of proper care of the back for subjects not seeking treatment were included. References of the articles meeting these inclusion criteria were also checked to identify other potential citations. Besides, a methodological study assessment of the included RCTs was performed.

RESULTS

Nine studies, all conducted at the workplace were included in this review. Their mean quality level was low (5.1/12) and among the four studies with a huge sample size (n > 400 subjects), only one had an acceptable methodological quality score (6/12). The education interventions differed widely from one study to another. No significant differences between the control and education groups were found at the follow-up in eight out of the nine studies on the incidence of back pain, disability and sick leave.

CONCLUSIONS

The results of the RCTs included in this review suggest that educational interventions mainly focused on a biomechanical/biomedical model are not effective in preventing LBP. However, taking into account the methodological quality level of the RCTs as well as the very short and heterogeneous interventions often proposed, additional high-quality studies with a longer education period are needed to conclude that such interventions are inefficient.

Subchondral bone and osteoarthritis: biological and cellular aspects

The subchondral bone is involved in the pathophysiology of osteoarthritis (OA), both by biochemical and mechanical pathways. Overloaded OA subchondral bone osteoblasts express a pro-angiogenic and pro-inflammatory phenotype which contributes to explain the structural changes (sclerosis and bone marrow lesion) visible in OA subchondral bone. Further, microfractures and conjonctivo-vascular structures constitute exchange routes between bone and the overlying cartilage for mediators produced by osteoblasts. This narrative review describes these physiopathological mechanisms and identifies possible therapeutic targets for pharmacological modalities.

Coll2-1, Coll2-1NO2 and myeloperoxidase serum levels in erosive and non-erosive osteoarthritis of the hands

OBJECTIVE

Erosive osteoarthritis of the hand (EHOA) is thought to be an aggressive variant of hand osteoarthritis (HOA) characterised by prominent local inflammation and radiographic aspects of bone erosions in interphalangeal (IP) joints. However, rare studies have until now investigated the value of biomarkers in these patients. Thus, we determined Coll2-1, a marker of type II collagen denaturation, its nitrated form (Coll2-1NO2) and myeloperoxidase (MPO) levels in serum of patients with EHOA vs non-EHOA and subsequently evaluated their relationships with disease indices of severity and activity.

METHODS

Coll2-1, Coll2-1NO2 and MPO were measured using specific immunoassays in 82 patients, 57 with EHOA, all females, median age 59 (41-74 yrs) and 20 with non-EHOA, all females, median age 55 (43-73 yrs), fulfilling the American College of Rheumatology (ACR) criteria for hand OA. EHOA was characterized by the presence of at least one central bone erosion on radiograph in the IP joints. Patients were also evaluated for disease duration, number of affected (swollen and painful or tender) joints, radiographic score (RS) by Kallman scale and high sensitivity C-reactive protein (hsCRP).

RESULTS

Serum levels of MPO were higher in EHOA (230.0 ± 152.1 ng/ml) than in non-EHOA (160.2 ± 111.5 ng/ml, P=0.037). Coll2-1NO2 levels trended towards an elevation in EHOA compared non-EHOA (0.40 ± 0.86 vs 0.22 ± 0.14 nmol/l, P=0.06), while Coll2-1 levels were not different. Correlations were found for disease duration and both MPO (R(2)=0.48, P=0.001) and Coll2-1NO2 (R(2)=0.73, P=0.01) after the splitting of the population in subgroups according to a cut off value above the 50th percentile. A correlation was found between hsCRP and MPO (R(2)=0.57, P=0.01).

CONCLUSIONS

This study clearly demonstrates an elevation of some serum biomarkers in EHOA, in comparison with non-EHOA. In particular, MPO, hsCRP and the ratio Coll2-1NO2/Coll2-1 discriminated the two subsets of hand osteoarthritis (HOA), and a trend was also observed for Coll2-1NO2. These data suggest that these biomarkers could be helpful for the diagnosis of EHOA.

Osteoarthritis year 2011 in review: biochemical markers of osteoarthritis: an overview of research and initiatives

The "year in review" session is a key moment of the Osteoarthritis Research Society International (OARSI) Congress. This is a unique opportunity for opinion leaders to summarize and comment the recent advances in one particular field of osteoarthritis research. This review is a summary of selected studies related to soluble biomarkers published between September 1st, 2010 and August 30th, 2011 and identified by a pubmed search using the terms "biomarkers" and "osteoarthritis". In addition, I have selected some works presented during the 2011 OARSI Congress. This year was dominated by the publication of a consensus paper on the qualification of osteoarthritis (OA) biomarkers by the OARSI/Food Drug Administration (FDA) Osteoarthritis Biomarkers Working Group, and of proteomes of chondrocyte vesicles, urine and serum.

Relationship between arthroscopic joint evaluation and the levels of Coll2-1, Coll2-1NO(2), and myeloperoxidase in the blood and synovial fluid of horses affected with osteochondrosis of the tarsocrural joint

OBJECTIVE

To evaluate the levels of plasmatic and synovial Coll2-1, Coll2-1NO(2) and myeloperoxidase (MPO) in horses with osteochondral lesions of the tarsocrural joint and to investigate how these levels relate to arthroscopic findings of inflammation and degeneration.

MATERIALS AND METHODS

Venous blood and synovial fluid samples were collected from 63 horses presented for arthroscopic removal of osteochondral fragments in the tarsocrural joint. Prior to removal of the osteochondral fragment, an exploration of the joint was performed and an inflammatory and degenerative score was determined. The blood and synovial levels of Coll2-1, Coll2-1NO(2) and MPO were also measured. The effects of the arthroscopic evaluation (inflammatory and degenerative classes) on the blood and synovial markers were evaluated using a linear model (GLM procedure), and correlations between biochemical markers in the blood and synovial fluid and the arthroscopic evaluation (inflammatory and degenerative classes) were established (Pearson's correlations).

RESULTS

Significantly higher levels of Coll2-1 were detected in synovial fluid of higher degenerative classes. There was a significant correlation between the degenerative score and the synovial levels of Coll2-1 (r=0.27). According to the logistic regression model, there was a significant effect of the degenerative class on synovial levels of Coll2-1.

CONCLUSIONS

Coll2-1 correlates well with the degenerative state of tarsocrural joints as evaluated by arthroscopy. This marker can therefore be classified as a burden-of-disease marker in the assessment of joint disease in horses.

Application of biomarkers in the development of drugs intended for the treatment of osteoarthritis

OBJECTIVE

Osteoarthritis (OA) is a chronic and slowly progressive disease for which biomarkers may be able to provide a more rapid indication of therapeutic responses to therapy than is currently available; this could accelerate and facilitate OA drug discovery and development programs. The goal of this document is to provide a summary and guide to the application of in vitro (biochemical and other soluble) biomarkers in the development of drugs for OA and to outline and stimulate a research agenda that will further this goal.

METHODS

The Biomarkers Working Group representing experts in the field of OA biomarker research from both academia and industry developed this consensus document between 2007 and 2009 at the behest of the Osteoarthritis Research Society International Federal Drug Administration initiative (OARSI FDA initiative).

RESULTS

This document summarizes definitions and classification systems for biomarkers, the current outcome measures used in OA clinical trials, applications and potential utility of biomarkers for development of OA therapeutics, the current state of qualification of OA-related biomarkers, pathways for biomarker qualification, critical needs to advance the use of biomarkers for drug development, recommendations regarding practices and clinical trials, and a research agenda to advance the science of OA-related biomarkers.

CONCLUSIONS

Although many OA-related biomarkers are currently available they exist in various states of qualification and validation. The biomarkers that are likely to have the earliest beneficial impact on clinical trials fall into two general categories, those that will allow targeting of subjects most likely to either respond and/or progress (prognostic value) within a reasonable and manageable time frame for a clinical study (for instance within 1-2 years for an OA trial), and those that provide early feedback for preclinical decision-making and for trial organizers that a drug is having the desired biochemical effect. As in vitro biomarkers are increasingly investigated in the context of specific drug treatments, advances in the field can be expected that will lead to rapid expansion of the list of available biomarkers with increasing understanding of the molecular processes that they represent.