Pfizer Inc. and Eli Lilly and Company announced positive top-line results from a Phase 3 study evaluating tanezumab in patients with moderate-to-severe chronic low back pain (CLBP). In the study, treatment with tanezumab 10 mg met the primary endpoint, demonstrating a statistically significant improvement in pain at 16 weeks compared to placebo. The tanezumab 5 mg arm demonstrated a numerical improvement in pain, but did not reach statistical significance compared to placebo at the week 16 analysis. Full results from this study will be submitted for future scientific publication and presentation. Tanezumab is a monoclonal antibody that is part of an investigational class of non-opioid pain medications known as nerve growth factor (NGF) inhibitors.
In this study, CLBP was defined as low back pain that had persisted for more than three consecutive months. Patients enrolled suffered from moderate-to-severe pain and had experienced inadequate pain relief from or intolerance to at least three different classes of analgesics. On average, they had CLBP for 10 years, and they reported a significant impact of their pain on their ability to function in everyday life. An estimated 33 million Americans have CLBP, and approximately eight million of these patients suffer from moderate-to-severe CLBP. The condition is a leading cause of disability, and currently available treatment options for CLBP do not meet the needs of all patients.
Tanezumab 5 mg or 10 mg was administered subcutaneously (SC) every eight weeks. Preliminary safety data showed that tanezumab was generally well tolerated during the 56-week treatment period. The trial also included a 24-week safety follow-up period, for a total of 80 weeks of observation. Overall, rapidly progressive osteoarthritis (RPOA) was observed among 1.4 percent of patients receiving tanezumab and 0.1 percent of patients in the other treatment groups. The ratio of RPOA type 1 (accelerated joint space narrowing) to RPOA type 2 (damage or deterioration of the joint) observed with tanezumab in the study was 6:1. Subchondral insufficiency fracture and total joint replacement were observed in 0.4 percent and 0.7 percent of tanezumab-treated patients, respectively, and were not observed in the other treatment groups. There were no events of osteonecrosis in the study.
“This study demonstrates the potential of tanezumab to treat individuals suffering from moderate-to-severe chronic low back pain who have been unable to achieve relief with currently available medicines,” said Ken Verburg, tanezumab development team leader, Pfizer Global Product Development. “This is one of the longest studies conducted to date in chronic low back pain. We look forward to further analyzing these results, and believe the data from this study will support our planned future global regulatory submissions in chronic low back pain.”
“Many patients living with chronic low back pain suffer from constant pain, which significantly impacts their ability to perform everyday tasks,” said Christi Shaw, president, Lilly Bio-Medicines. “Lilly and Pfizer recognize the unmet needs for those living with this life-altering and debilitating condition, and continue to advance tanezumab as an innovative non-opioid treatment for these patients.”
In addition to CLBP, the ongoing Phase 3 program for tanezumab includes studies in osteoarthritis (OA) pain and cancer pain (due to bone metastases). Positive results from two Phase 3 OA pain studies evaluating 16 and 24 weeks of treatment with tanezumab were previously reported. One additional Phase 3 study in OA pain and one additional Phase 3 study in CLBP will read out this year.