Tanezumab for the Treatment of Pain from Osteoarthritis of the Knee

Modeling studies show that increased expression of nerve growth factor is associated with increased pain. This study tested the safety and efficacy of the monoclonal antibody tanezumab — which targets nerve growth factor — for the treatment of knee pain in patients with osteoarthritis. Nerve growth factor is a neurotrophin that regulates the structure and function of responsive sensory neurons, including small-diameter nociceptive afferents. There has been increasing recognition of the potential role of nerve growth factor in pain modulation through nociceptor sensitization. 1 – 7 In animals and humans, exogenous nerve growth factor increases pain either locally or systemically, depending on the dose and the route of administration. 8 , 9 Increased expression of nerve growth factor is found in inflamed tissues from patients with conditions such as arthritis, pancreatitis, and prostatitis. 10 – 12 Levels of nerve growth factor are also elevated in animal models of inflammatory pain, . . .