Eli Lilly reports positive data from osteoarthritis pain study

According to the company, duloxetine-treated patients showed greater reductions from baseline on the primary endpoint, the 24-hour average pain score on the Brief Pain Inventory (BPI), compared with placebo-treated patients. In the study, 65% of duloxetine-treated patients experienced a clinically significant (at least 30%) improvement in pain, compared with 44% of placebo-treated patients.

The duloxetine-treated patients also showed improved physical function, compared with placebo-treated patients, as measured by the Western Ontario and McMaster Osteoarthritis Index (WOMAC). In this study, patients on duloxetine did not show statistically significant improvements on the WOMAC pain and stiffness subscales compared with placebo, the company said.

In this 13-week double-blind trial, patients were at least 40 years of age without a current diagnosis of major depressive disorder; with no confounding painful conditions or diagnosis of inflammatory arthritis or autoimmune disorders; and with no invasive therapy of the knee in the past three months, knee arthroscopy within the past year or joint replacement of the index knee at anytime.

Patients were randomized to duloxetine (n=128) or placebo (n=128) and stratified by whether or not they used nonsteroidal anti-inflammatory drugs. At week seven, patients who showed suboptimal response to the 60mg (33 patients) dose had their dose increased to 120mg. The primary efficacy endpoint of the study was the BPI 24-hour average pain rating, which was analyzed using a mixed-model repeated measures approach.