Combined chondroitin sulfate and glucosamine for painful knee osteoarthritis: a multicentre, randomised, double-blind, non-inferiority trial versus celecoxib

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.

Efficacy and safety of low-dose SoluMatrix meloxicam in the treatment of osteoarthritis pain: a 12-week, phase 3 study

OBJECTIVE

Nonsteroidal anti-inflammatory drugs (NSAIDs) such as meloxicam are commonly used to treat osteoarthritis (OA) but are associated with potentially serious dose-related adverse events (AEs). SoluMatrix meloxicam has been developed with the goal of enabling effective treatment at low doses. This phase 3 study evaluated the efficacy and safety of low-dose SoluMatrix meloxicam capsules 5 mg and 10 mg administered once daily for 12 weeks in patients with OA-related pain.

RESEARCH DESIGN AND METHODS

This randomized, double-blind study enrolled patients ≥40 years of age with confirmed hip or knee OA (Kellgren-Lawrence grade II-III) who were chronic users of NSAIDs and/or acetaminophen for OA pain and had Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale mean scores ≥40 mm. Eligible patients experienced an OA pain flare (defined as a ≥15 mm increase in the WOMAC pain subscale score) following discontinuation of NSAIDs/acetaminophen. Patients were randomized to receive once-daily SoluMatrix meloxicam 5 mg or 10 mg, or placebo for 12 weeks. ClinicalTrials.gov identifier: NCT01787188.

MAIN OUTCOME MEASURES

The primary outcome measure was the mean change from baseline in WOMAC pain subscale score at week 12.

RESULTS

Low-dose SoluMatrix meloxicam 5 mg (-36.52 [2.49]; P = 0.0005) and 10 mg (-34.41 [2.68]; P = 0.0059) once-daily treatment significantly reduced the mean (standard error) WOMAC pain subscale score from baseline at week 12 compared with placebo (-25.68 [2.64]). Patients treated with SoluMatrix meloxicam 5 mg or 10 mg reported significantly greater improvements in total WOMAC score and in WOMAC stiffness and function subscale scores at 12 weeks compared with placebo. The most common AEs in the combined low-dose SoluMatrix meloxicam group were headache, diarrhea, nausea, osteoarthritis, and urinary tract infection.

CONCLUSIONS

Low-dose SoluMatrix meloxicam may have a potential role as a new therapeutic option for the management of OA-related pain.

Effectiveness and safety of Glucosamine, chondroitin, the two in combination, or celecoxib in the treatment of osteoarthritis of the knee

This study aimed to investigate the effectiveness and safety of glucosamine, chondroitin, the two in combination, or celecoxib in the treatment of knee osteoarthritis (OA). PubMed, Embase and Cochrane Library were searched through from inception to February 2015. A total of 54 studies covering 16427 patients were included. Glucosamine plus chondroitin, glucosamine alone, and celecoxib were all more effective than placebo in pain relief and function improvement. Specifically, celecoxib is most likely to be the best treatment option, followed by the combination group. All treatment options showed clinically significant improvement from baseline pain, but only glucosamine plus chondroitin showed clinically significant improvement from baseline function. In terms of the structure-modifying effect, both glucosamine alone and chondroitin alone achieved a statistically significant reduction in joint space narrowing. Although no significant difference was observed among the five options with respect to the three major adverse effects (withdrawal due to adverse events, serious adverse events and the number of patients with adverse events), the additional classical meta-analysis showed that celecoxib exhibited a higher rate of gastrointestinal adverse effect comparing with the placebo group. The present study provided evidence for the symptomatic efficacy of glucosamine plus chondroitin in the treatment of knee OA.

[An antinociceptive effect of chondroprotectors: a myth or a reality?]

Authors reviewed the literature on the efficacy of chondroprotectors in the treatment of chronic pain syndromes in comparison with placebo and other analgesics to discover the own antinociceptive effect of these drugs and mechanisms by which it occurs. Authors evaluated the results of various clinical studies on the effect of symptomatic slow-acting drugs for osteoarthritis (SYSADOA) on chronic pain syndrome in osteoarthritis and low back pain. We compared their effects with those of NSAIDs, celecoxib, or placebo. Assessment of pain and functional status was performed using WOMAC, VASandLeken's index as well as the Roland--Morrisquality of life questionnaire. The review of a number of clinical studies revealed a definite antinociceptive and anti-inflammatory effect of SYSADOA comparable with NSAIDs not only in the treatment of osteoarthritis, but also in chronic back pain, which is characterized by early onset and gradual development with a long-term retention of the result even after discontinuation of therapy. It has been shown that SYSADOA are able to reduce the level of inflammatory cytokines in the blood (IL-6, C-reactive protein) and to activate the production of anti-inflammatory cytokine IL-10 in the synovial membrane. It is shown that blocking of the effects of interleukin 1-beta and thereby inhibition of inflammatory enzymes like nitric oxide synthase and cyclooxygenase-2 is one of the points of glucosamine chondrocytes application. The data obtained in numerous studies that confirm the ability of SYSADOA to inhibit proinflammatory cytokines open the new perspectives for their use in the treatment of not only joint pain but also other chronic pain syndromes.