Pfizer and Eli Lilly’s Osteoarthritis Pain Drug Hits All 3 Endpoints in Phase III Trial

Pfizer and Eli Lilly released results from its 16-week Phase III clinical trial in patients with osteoarthritis (OA) pain receiving a subcutaneous dose of tanezumab. The drug hit all three co-primary endpoints.

Tanezumab is a humanized monoclonal antibody being evaluated for OA pain, chronic lower back pain (CLBP) and cancer pain due to bone metastases. It selectively targets, binds to and inhibits NGF. NGF levels rise in the body as the result of injury, inflammation or chronic pain states.

In the study, a total of 698 patients were randomized in a 1:1:1 ratio to receive two injections of the drug over a 16-week period, once every eight weeks. One group received two doses of placebo, another two doses of tanezumab 2.5 mg, and the third received one dose of tanezumab 2.5 mg followed by a single dose of tanezumab 5 mg eight weeks later. The effectiveness of the drug was measured by changes from baseline at 16 weeks in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAZ C) Pain subscale, the WOMAC Physical Function subscale, and the patient’s Global Assessment of OA.

The drug met all three co-primary endpoints in both treatment arms and appeared to be well-tolerated. Only about one percent of patients stopped treatment because of side effects. Less than 1.5 percent of patients in the treatment arms showed rapidly progressive osteoarthritis, which was not seen in the placebo arm. This is the type of data, however, that is going to receive plenty of scrutiny by regulators and researchers, because of overarching concerns over NGF inhibitor side effects.

“There is a substantial need for innovative new treatment options for osteoarthritis, as many patients are unable to find relief with currently available medicines and continue to suffer,” said Ken Verburg, tanezumab development team leader, Pfizer Global Product Development, in a statement. “We are encouraged by these results, which speak to the potential of tanezumab as a non-opioid treatment option for pain reduction and improvement in physical function in people living with osteoarthritis pain.”

Prior to 2015, the U.S. Food and Drug Administration (FDA) placed a hold on clinical trials of drugs that targeted NGF because of the possibility it made osteoarthritis worse in a small percentage of patients. That was lifted in 2015.

“Safety concerns have been an overhang on the tanezumab opportunity,” said Louis Chen, an analyst with Cantor Fitzgerald, in a note to clients. “The data today should alleviate some of those concerns, in our opinion.”

Osteoarthritis affects about 20 million people in the U.S., and is the most common form of arthritis. Typically, physicians and patients turn to opioids to treat OA pain, but the opioid crisis is raising concerns about treatment and pressuring physicians to seek alternative pain treatments.

“Worldwide, millions are living with osteoarthritis, a progressive disease that can significantly impact people’s everyday lives,” said Christi Shaw, senior vice president, Eli Lilly and Company and president, Lilly Bio-Medicines, in a statement. “We look forward to continuing to advance tanezumab in our ongoing global Phase III development program, which includes six studies in approximately 7,000 patients with osteoarthritis, chronic low back pain and cancer pain.”