RESUMEN
OBJECTIVE: To demonstrate clinical equivalence between two standardized Ayurveda (India) formulations (SGCG and SGC), glucosamine and celecoxib (NSAID). METHODS: Ayurvedic formulations (extracts of Tinospora cordifolia, Zingiber officinale, Emblica officinalis, Boswellia serrata), glucosamine sulphate (2 g daily) and celecoxib (200 mg daily) were evaluated in a randomized, double-blind, parallel-efficacy, four-arm, multicentre equivalence drug trial of 24 weeks duration. A total of 440 eligible patients suffering from symptomatic knee OA were enrolled and monitored as per protocol. Primary efficacy variables were active body weight-bearing pain (visual analogue scale) and modified WOMAC pain and functional difficulty Likert score (for knee and hip); the corresponding a priori equivalence ranges were ±1.5 cm, ±2.5 and ±8.5. RESULTS: Differences between the intervention arms for mean changes in primary efficacy variables were within the equivalence range by intent-to-treat and per protocol analysis. Twenty-six patients showed asymptomatic increased serum glutamic pyruvic transaminase (SGPT) with otherwise normal liver function; seven patients (Ayurvedic intervention) were withdrawn and SGPT normalized after stopping the drug. Other adverse events were mild and did not differ by intervention. Overall, 28% of patients withdrew from the study. CONCLUSION: In this 6-month controlled study of knee OA, Ayurvedic formulations (especially SGCG) significantly reduced knee pain and improved knee function and were equivalent to glucosamine and celecoxib. The unexpected SGPT rise requires further safety assessment. TRIAL REGISTRATION: Clinical Drug Trial Registry-India, www.ctri.nic.in, CTRI/2008/091/000063.