Identification of formulation parameters that affect the analgesic efficacy of ProGel-Dex - A thermoresponsive polymeric dexamethasone prodrug for chronic arthritis pain relief.

The relief of joint pain is one of the main objectives in the clinical management of arthritis. Although significant strides have been made in improving management of rheumatoid and related forms of inflammatory arthritis, there are still major unmet needs for therapies that selectively provide potent, sustained and safe joint pain relief, especially among patients with osteoarthritis (OA), the most common form of arthritis. We have recently developed ProGel-Dex, an N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-based thermoresponsive dexamethasone (Dex) prodrug, which forms a hydrogel upon intra-articular administration and provides sustained improvement in pain-related behavior and inflammation in rodent models of arthritis.