Although the use of combined hyaluronic acid 80 mg and sorbitol 160 mg and; hylan GF-20 48 mg were both found to be safe, but non-inferiority of hyaluronic acid and sorbitol combination in comparison with hylan GF-20 was found at day 168 for concerning WOMAC pain score in OA patients, demonstated a study published in Advances in Therapy.

This randomized, double-blinded study comprised of 202 patients (mean age 65 years, BMI 27.4 kg/m², 66% female) divided in two groups as:

• Group HA1: Patients received Hyaluronic acid 80 mg and Sorbitol 160 mg injection
• Group HA2: Patients received Hylan GF-20 48 mg injection

Initially at day 0, the average VAS pain score was noted as 62.5. At Day 168, the Western Ontario and McMaster University (WOMAC) pain scores were regarded as the primary endpoint. Regular assessment of this index by the patient for a week after the injection and subsequently at Day 14 was the secondary endpoint. Additionally, WOMAC pain scores, stiffness, function and overall scores was investigated at different time periods (Day 28, Day 84 and Day 168). The efficacy and satisfaction were evaluated by evaluator and patient via a 7 points Likert scale. Number of strict responders in both the groups wre assessed.

A decrease in the WOMAC pain score i.e. - 29.2 ± 24.1 (SD) in the Group HA1 and - 31.6 ± 25.5 (SD) in the Group HA2 was observed, corroborating the non-inferiority of the hyaluronic acid and 160 mg sorbitol combination (P = 0.57). Other than stiffness at Day 28 (P favoring HA2 group therapy), no noteworthy difference was observed at time periods mentioned for all the concerning secondary end points. Both the therapies were well tolerated with comparable rate of responders. Four patients in the HA1 group and three in HA2 group reported critical adverse events.