Higher dose of Pfizer, Eli Lilly's tanezumab hits main goals in late-stage osteoarthritis pain study

Pfizer and Eli Lilly reported Tuesday that in a Phase III study, the higher dose of tanezumab in patients with moderate-to-severe osteoarthritis (OA) pain met all three co-primary endpoints at 24 weeks. However, the companies said that while the lower dose of the NGF inhibitor significantly improved pain and physical function versus placebo, top-line results showed that there was no difference in the patients' overall assessment of their OA. 

The study enrolled 849 patients with moderate-to-severe OA pain who had experienced inadequate pain relief from or intolerance to at least three different classes of analgesics, and on average had OA for more than six years. Participants were randomly assigned to receive three subcutaneous injections of tanezumab, at doses of either 2.5 mg or 5 mg, or placebo, once every eight weeks over the treatment period. Primary endpoints of the trial were changes from baseline at 24 weeks in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale, the WOMAC physical function subscale and the patients' global assessment of OA. 

Preliminary safety data illustrated that tanezumab was well tolerated during the treatment period, although rapidly progressive osteoarthritis was observed in 2.1 percent of patients given the drug, versus no cases in the placebo arm. Pfizer and Eli Lilly said there was one event of osteonecrosis and one event of subchondral insufficiency fracture observed in tanezumab-treated patients, and no events observed in the placebo arm, while the rate of total joint replacement was similar across the tanezumab groups and placebo. Detailed results from the trial will be submitted to a future medical conference.

"These findings build on the previously reported positive Phase III results in patients with osteoarthritis pain," remarked Ken Verburg, tanezumab development team leader at Pfizer Global Product Development. Last October, the drugmakers unveiled detailed late-stage study results demonstrating that tanezumab reduced OA pain by at least 50 percent in more than half of treated patients. The Phase III programme for tanezumab includes six studies in approximately 7000 patients with OA pain, chronic low back pain and cancer pain due to bone metastases. 

Pfizer and Eli Lilly entered into a partnership in 2013 to jointly develop and market tanezumab. The drug was subsequently granted a fast-track designation by the FDA for the treatment of chronic pain associated with OA and chronic low back pain. 

For related analysis, see The drugs that will shape 2019.

To read more Top Story articles, click here.