Abstract: AIM: To investigate the efficacy and safety of liduofen in the treatment of patients with osteoarthritis of the knee joint.METHODS: A randomized, double-blind, parallel-controlled, multi-centre study was adapted to compare the efficacy and safety between liduofen and Olfen-75 in 136 patients.Patients were randomly assigned into two groups:liduofen group which was received 75 mg (diclofenac) Liduofen injection (n=69) once a day for seven days and Olfen group which was received 75 mg (diclofenac) Olfen-75 injection (n=67) once a day for seven days.RESULTS: After the treatment, similar improvements for rest pain, pain on exercise, swelling of joint, pressing pain of joint, knee joint bend extend function measured using a 10 cm visual analogue scale was performed in two groups.In Olfen-75 group, the rate of efficacy was 62.69% in the 3rd day, 95.76% in the 5th day and 97.88% in the 7th day. While in liduofen group, the rate of efficacy was 57.97% in the 3rd day, 93.87% in the 5th day and 96.94% in the 7th day.In liduofen and Olfen-75 groups, the progressive rates were 56.72% and 55.07%, respectively. The total improvement rates were 89.85% and 92.54% respectively (P>0.05), and the rates of side effects were 0% and 1.49%, respectively (P>0.05).CONCLUSION: Liduofen is an effective and safty drug inthe treatment of patients with osteoarthritis of the knee joint. There is no significant difference on efficacy and safety between the two groups using liduofen and Olfen-75.

Key words: liduofen, Olfen-75, injection, efficacy, sideeffects, osteoarthritis of the knee joint