Background:
A randomized, double-blind trial (56-week treatment; 24-week follow-up) was conducted in patients with Chronic Low Back Pain (CLBP) and history of inadequate response/intolerance to standard of care analgesics.

Methods:
Patients received placebo, subcutaneous tanezumab (5 or 10mg every 8 weeks), or oral tramadol prolonged release (100-300mg/day). At week 16, patients receiving placebo were switched (1:1) to tanezumab 5 or 10mg. Low Back Pain Intensity (LBPI) and Roland Morris Disability Questionnaire (RMDQ) were assessed through week 56. Safety, including joint safety, was assessed through week 80. 

Results:
Improvements in LBPI and RMDQ, relative to baseline and tramadol (N=605; mean dose=209mg/day), were maintained throughout the study with tanezumab 5mg (N=407) and 10mg (N=407) but were not significantly better than tramadol at week 56 (Figure). Adverse event (AE) rates through week 56 were 58.3%, 63.7%, and 65.4% in the tanezumab 5mg (N=506), tanezumab 10mg (N=502), and tramadol (N=602) groups, with treatment discontinuation rates of 6.7%, 7.4%, and 10.5%, respectively. Rapidly progressive osteoarthritis occurred in 1.4% (type-1 n=12; type-2 n=2) and 0.2% (type-1 n=1) of tanezumab- and tramadol-treated patients, respectively. Subchondral insufficiency fracture and total joint replacement occurred in 0.4% (n=4) and 0.7% (n=7) of tanezumab-treated patients; none with tramadol. No joint events occurred with placebo. 

Conclusion: 
Improvements in pain and function with tanezumab were maintained long-term, but were not significantly better than tramadol at week 56. AE-related treatment discontinuations were more frequent with tramadol; joint safety events were more frequent with tanezumab.

03 - SUBCUTANEOUS TANEZUMAB VERSUS TRAMADOL FOR CHRONIC LOW BACK PAIN: EFFICACY AND SAFETY RESULTS FROM A 56-WEEK PHASE 3 STUDY WITH A 24-WEEK FOLLOW UP PERIOD