Pragmatic evaluation of prescription glucosamine sulfate (pGS) in knee osteoarthritis: insights from a Filipino cohort.

INTRODUCTION

The real-world effectiveness and tolerability of prescription glucosamine sulfate (pGS) in reducing knee osteoarthritis (KOA) symptoms in a Filipino cohort was evaluated.

METHODS

This 8-week, pragmatic, open-label, multicenter study enrolled 281 Filipino adults with mild-to-moderate (Kellgren-Lawrence grade 2-3) KOA. Participants received pGS 1,500 mg once daily. Outcomes included changes from baseline assessed with the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Visual Analog Scale (VAS) for pain at Weeks 4, 6, and 8. Tolerability was evaluated through adverse event monitoring.

RESULTS

Among 281 treated patients, 277 (98.6%) completed the study, and 245 (~88.0%) received pGS alone for the full period. These patients demonstrated rapid, sustained symptom improvement, with knee pain decreasing by Week 4 and continuing through Week 8. After 4 weeks, 132 patients (~47.0%) had already achieved ≥50.0% pain reduction. By Week 8, WOMAC pain showed a least squares (LS) mean change of -11.96 (95% CI: -12.26 to -11.67), with marked improvements in stiffness, physical function, and total score. VAS pain decreased from 68.4 mm at baseline to 11.9 mm at Week 8, consistent with meaningful clinical benefit. Treatment satisfaction was high, with 98.78% satisfied at Week 8 and a mean psychometric VAS score of 9.0. Patients with more advanced KOA requiring add-on therapy (n = 34) also demonstrated pain improvement, with an LS mean change in WOMAC pain of -8.81 (95% CI: -9.62 to -7.99). Overall, adverse events occurred in 4.6% of patients, were mostly mild, and led to only one withdrawal, confirming good tolerability of pGS as monotherapy and in multimodal treatment.

CONCLUSION

Prescription glucosamine sulfate improved pain, stiffness, and function in Filipino patients with mild-to-moderate KOA as early as Week 4, sustained through Week 8. Treatment was well tolerated, with high satisfaction and one discontinuation. Most patients (~88%) were effectively managed with pGS monotherapy, while add-on celecoxib benefited those with insufficient response, supporting a multimodal approach for KOA symptom control in routine care.