OBJECTIVE: Evaluate efficacy and safety of tanezumab, a humanized monoclonal 
antibody against nerve growth factor, in neuropathic pain.
DESIGN: Two randomized controlled trials.
SUBJECTS: Patients with pain due to diabetic peripheral neuropathy (DPN) or 
postherpetic neuralgia (PHN).
METHODS: In the DPN study, patients received subcutaneous tanezumab 20 mg or 
placebo on Day 1 and Week 8. Evaluations included change from baseline in 
average DPN pain (primary endpoint), Patient's Global Assessment of DPN, and 
safety (including neuropathy assessments). Due to a partial clinical hold 
limiting enrollment and treatment duration, the prespecified landmark analysis 
was modified post hoc from Week 16 to Week 8. In the PHN study, patients 
received intravenous tanezumab 50 μg/kg, tanezumab 200 μg/kg, or placebo on Day 
1. Evaluations included change from baseline in average daily pain (primary 
endpoint), Brief Pain Inventory-short form, Patient's Global Assessment of pain 
from PHN, and safety.
RESULTS: Mean DPN pain reduction from baseline to Week 8 was greater with 
tanezumab vs placebo (P = 0.009); differences in Patient's Global Assessment of 
DPN were not significant (P > 0.05). Neither tanezumab dose resulted in 
significant differences vs placebo in efficacy in PHN (P > 0.05), although 
tanezumab 200 μg/kg provided some benefit. Neuropathy assessments showed no 
meaningful changes.
CONCLUSIONS: Tanezumab provided effective pain reduction in DPN. In PHN, only 
the highest tanezumab dose reduced pain; treatment differences were not 
significant. No new safety concerns were observed despite preexisting 
neuropathy.