Pfizer and Lilly Announce Latest Top-Line Endpoint Results of Phase III Tanezumab Trial in Osteoarthritis Patients

Pfizer Inc and Eli Lilly and Company are rejoicing the results of a new Phase-3 study, this week, which evaluated the efficacy and safety of their new tanezumab 2.5 mg and 5 gm for osteoarthritis. The study was designed to compare the drug’s long-term joint safety and 16-week efficacy against other traditional nonsteroidal anti-inflammatory drugs in those patients who have moderate-to-severe osteoarthritis of the knee or the hip.  

The 5mg treatment met two out of three co-primary efficacy endpoints, which means it showed a statistically significant improvement in pain and physical function (compared with NSAIDs).  The 2.5mg treatment, however, did not show any statistically significant improvement over NSAIDs.  Neither seemed to have a statistically different effect on osteoarthritis. 

In terms of the safety analysis, it appears that the both courses of tanezumab tested in the trial had a higher rate of joint safety events than traditional NSAID treatments in an 80 week period.  It should be noted that joint safety, in this regard, it is a composite measure of several adjudicated outcomes rapidly progressive osteoarthritis types 1 and 2, as well as subchondral insufficiency fracture, osteonecrosis, and pathological fracture.  

With that in mind, the companies are now looking at where to take this new drug.  While the study results suggests an improvement on previous trials, the endpoints are still out of view.  Pfizer Global Product Development tanezumab team leader Ken Verburg explains, “We are analyzing these findings in the context of the recent Phase 3 results as we assess potential next steps for tanezumab. We plan to review the totality of data from our clinical development program for tanezumab with regulatory authorities.”

It should be noted that there were 10 deaths associated with this latest study.  9 of these deaths were among the tanezumab treatment arms and the final death was in the NSAID treatment arm.  Fortunately, none of these deaths have been determined to be treatment-related.

Similarly, Lilly Bio-Medicines president Christi Shaw comments, “Lilly and Pfizer recognize the significant unmet needs for patients living with osteoarthritis. We are committed to understanding these results for people who suffer from chronic pain.”