A Pilot Clinical Study of the Efficacy and Safety of Phellinus Linteus (Sanghuang) Extract Treatment for Knee Osteoarthritis

Background: To evaluate the efficacy and safety of Phellinus linteus (PL) extract for the treatment of knee osteoarthritis (KOA) a pilot clinical study was performed. Methods: There were 24 patients with KOA who enrolled in this double-blind, randomized, controlled, clinical trial. There were 3 groups: PL 1,000 mg/day (PL 1,000), PL 1,500 mg/day (PL 1,500), and dextrin 3,000 mg/day (placebo). Patients took capsules twice a day, 3 capsules at a time, over 8 weeks. Patients were monitored prior to treatment (Visit 1: Week 0), and followed up every 4 weeks (Visit 2: Week 4 and Visit 3: Week 8) where outcome measurements were taken. The primary outcome measure was the score from the Korean version of the Western Ontario and McMasters Universities from baseline to Week 8. The secondary outcomes were measurements from the visual analog scale, quality of life scale, erythrocyte sedimentation, and c-reactive protein. Adverse events were recorded at every visit. Results: The Korean version of the Western Ontario and McMasters Universities score showed the greatest improvement in symptoms of KOA in the PL 1,500 group compared with the placebo group. The erythrocyte sedimentation tended to decrease in the PL 1,500 group compared with the placebo group (which was within the normal range). The visual analog scale score decreased in all groups, with no significant differences between groups. No adverse events related to PL were reported. There were no abnormal hematological or physical findings. Conclusion: This pilot clinical trial was the first step to assess the efficacy and safety of PL used in the treatment of patients with KOA.