DESCRIPTION

FLEXOST is indicated for the treatment and prevention of osteoarthritis. Its composition is formulated from natural products Glucosamine sulfate 220mg, chondroitin 220mg.

CLINICAL STUDIES

The efficacy and safety of FLEXOST in the treatment and prevention of osteoarthritis has been evaluated in 22 clinical trials (see table 1) of up to 36-month duration, involving over 6500 patients. FLEXOST , when taken as needed up to three times per day, was shown to be effective in improving joint space narrowing which is the prime indicator of arthritic joint damage and inhibiting progression of degenerative cartilage lesions. Clinical studies also showed significantly superior to placebo and superior to ibuprofen.

The efficacy of glucosamine for arthritic complaints has been extensively studied and three recent meta-analyses (McAlindon et al., 2000; Richy et al., 2003; Towheed et al., 2004) that critically review randomized controlled trials (RCTs) are available. McAlindon et al. (2000) conclude that glucosamine was moderately efficacious for relief of arthritic complaints. Richy et al. (2003) conclude that glucosamine had highly significant efficacy on all aspects of knee osteoarthritis including joint space narrowing, pain, and mobility scores. Towheed et al. (2004) report that

‘‘In the 13 RCTs in which glucosamine was compared to placebo, glucosamine was found to be superior in all RCTs, except one. In the four RCTs in which glucosamine was compared to an NSAID, glucosamine was superior in two and equivalent in two.’’ In our current evaluation 23 clinical studies of patients with osteoarthritis were reviewed (Table 2); this does not include the three studies of temporo-mandibular joint (TMJ) symptoms.

Twelve studies reported significant differences and included P-values (from 0.05 to 0.001). Seven indicated that significant  improvement was seen but did not provide P-values; a P-value of 0.05 was assigned to these studies. Only three studies indicated that no significant difference was seen and two noted a slight improvement with glucosamine administration; a P-value of 0.1 was assigned to these studies since they reported favorable but not quite statistically significant results. The average of all reported and imputed P-values for the 22 studies was 0.040 and the median P-value was 0.05. While a detailed analysis of efficacy was not undertaken, this survey indicates that glucosamine administration, at a dose of  1500 mg/day, is moderately effective in decreasing arthritic complaints.

Objective measures of safety

In two metabolic ward studies, volunteers have received large doses of glucosamine intravenously over 300 min. Pouwels et al. (2001) intravenously infused _7.2 g of glucosamine as the sulfate salt over a 300 min period into 10 healthy volunteers. This was well tolerated and not associated with reported side effects. Monauni et al. (2000) intravenously infused 9.7 g of glucosamine over a 300 min period into 10 healthy volunteers. Again this was well tolerated with no reported side effects. When they subsequently intravenously infused 30.5 g of glucosamine—achieving plasma levels >20-fold higher than would be expected with usual doses of oral glucosamine—into five healthy volunteers, this dose was well tolerated by four subjects and only one had symptoms—he developed a headache. Thirteen studies reported specific safety measures including some of these assessments: chemistry panel including liver and kidney safety assessments, hematologic values (white blood count, red blood count, hemoglobin, and platelet count), urinalyses, occult blood measurements of stool, and cardiovascular parameters including blood pressure and pulse rate (Table 3). None of the studies reported adverse effects on these measurements from glucosamine administration. In general these safety reports included >800 subjects treated for a weighted average of _40 weeks. Specifically the number of studies assessing various parameters were as follows: chemistry panel, 12; hematologic parameters, 13; urinalyses, 10; occult blood in stool, 3; and cardiovascular parameters, 6. Blood pressure and pulse rate were monitored continuously for the 21 subjects who had large amounts of glucosamine infused intravenously with no reported adverse effects (Monauni et al., 2000; Pouwels et al., 2001). None of the studies reported significant changes in these parameters.