We intra-articularly administered high molecular weight sodium hyaluronate (NRD101) at a single dose of 15similar50 mg in the knee in 29 healthy male volunteers and evaluated its safety and pharmacokinetics.

1) Symptoms such as slight pain during motion and malaise developed but were not dose-dependent. Similar symptoms were also observed with the placebo. Increases in WBC, GOT and GPT were observed in some subjects, but these changes were transient and not dose-dependent. The blood HA concentration did not increase. No abnormalities associated with NRD101 were observed, and this drug was well tolerated.

2) The serum HA concentration changed in the range of about 30similar150 ng/ml after administration of NRD101 at each dose or the placebo. Thus, the serum HA concentration did not significantly exceed its physiological range after administration of exogenous HA into the knee.